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Purpose: This preregistered trial investigated how 6 weeks of unilateral flywheel leg-curl and hip-extension training impact isokinetic, isometric, and flywheel strength and power outcomes. Methods: The study involved 11 male university athletes (age 22 [2] y; body mass 77.2 [11.3] kg; height 1.74 [0.09] m) with one leg randomly allocated to flywheel training and one leg to control. Unilateral eccentric and isometric knee-flexion torque and flywheel unilateral leg-curl and hip-extension peak power were tested. Training intensity and volume (3–4 sets of 6 + 2 repetitions) were progressively increased. Results: The intervention enhanced hip-extension concentric (P <.01, d = 1.76, large) and eccentric (P <.01, d = 1.33, large) peak power more than the control (significant interaction effect). Similarly, eccentric (P =.023, d = 1.05, moderate) peak power was enhanced for the leg curl. No statistically significant differences between conditions were found for isokinetic eccentric (P =.086, d = 0.77, moderate) and isometric (P =.431, d = 0.36, small) knee-flexor strength or leg-curl concentric peak power (P =.339, d = 0.52, small). Statistical parametric mapping analysis of torque–angle curves also revealed no significant (P >.05) time–limb interaction effect at any joint angle. Conclusion: Unilateral flywheel hamstring training improved knee-flexor eccentric peak power during unilateral flywheel exercise but not flywheel concentric, isokinetic eccentric, or isometric (long-lever) knee-flexor strength. [ABSTRACT FROM AUTHOR]

Purpose: To compare the effects between resisted sled sprint training (RSS) and unresisted sprint training (URS) on sprint and acceleration performance, vertical jump, and maximal strength during an 8-week period of preseason training. Methods: Twenty-six recreational active rugby players were randomly divided into either RSS or URS training groups and then performed 8 weeks of training, 2 sessions/wk of sprint-specific training program. The RSS group performed sprints by towing a sled overloaded with 12.6% of body mass for 2 of the 3 sets of 3 × 20-m sprints, plus one set was carried out with unresisted modality. The URS groups performed 3 sets of 3 × 20-m unresisted sprints. The measures of 10- and 30-m sprint times, vertical jump, and 3-repetition-maximum (3-RM) squat tests were performed at baseline and after 8 weeks. Results: Ten- and 30-m sprint times (P <.05 and η p 2 >.44) improved significantly more in RSS than in URS. Both groups improved significantly in vertical jump and 3-RM squat tests; however, no significant differences (P >.1 and η p 2 <.11) between groups were found. Conclusions: Our findings indicate that an 8-week program of RSS is more effective than URS for enhancing sprint time performance in male recreational active rugby players. In addition, these data suggest that a sled overload corresponding to 12.6% of body mass can induce positive effects on both acceleration and speed performance in recreational active rugby players. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to examine how the interplay of stressor (e.g. fear of missing out, FoMO) and strains (e.g. perceived social overload, communication overload, information overload and system feature overload) in social networking sites (SNS) use can contribute to users' SNS fatigue from a configurational view. Design/methodology/approach: Data were collected among 363 SNS users in China via an online survey, and fuzzy-set qualitative comparative analysis (fsQCA) was applied in this study to scrutinize the different combinations of FoMO and overload that contribute to the same outcome of SNS fatigue. Findings: Six combinations of casual conditions were identified to underlie SNS fatigue. The results showed that FoMO, perceived information overload and system feature overload are the core conditions that contribute to SNS fatigue when combined with other types of overloads. Originality/value: The current work supplements the research findings on SNS fatigue by identifying the configurations contributing to SNS fatigue from the joint effects of stressor (FoMO) and strain (perceived social overload, communication overload, information overload and system feature overload) and by providing explanations for SNS fatigue from the configurational perspective. [ABSTRACT FROM AUTHOR]

Background: Resting heart rate (HR) and HR variability (HRV) are widely used parameters to assess cardiac autonomic nervous system function noninvasively. While resting assessments can be performed during sleep or after awakening, it would be relevant to know how interchangeable the results of these measurements are. This study aimed at examining the alignment between nocturnal and morning assessments during regular endurance training and in response to intensive training. A total of 24 recreational runners performed a 3-week baseline period (BL) and a 2-week overload (OL) period (Lucia's training impulse + 80%). Their running performance was assessed with a 3000-m running test after the BL and OL. The participants recorded daily their nocturnal HR and HRV (the natural logarithm of the root mean square of successive differences; LnRMSSD) with a photoplethysmography-based wrist device and performed an orthostatic test (2-min supine, 2-min standing) every morning with a chest-strap HR sensor. The HR and LnRMSSD segments that were analyzed from the nocturnal recordings included start value (SleepStart), end value (SleepEnd), first 4-h segment 30 min after detected sleep onset (Sleep4h), and full sleep time (SleepFull). The morning segments consisted of the last-minute average in both body positions. All segments were compared at BL and in response to the 3000-m test and OL. Results: All nocturnal HR and LnRMSSD segments correlated with supine and standing segments at BL (r = 0.42 to 0.91, p < 0.05). After the 3000-m test, the HR increased and LnRMSSD decreased only in the SleepStart, Sleep4h, and SleepFull segments (p < 0.05). In response to the OL, the standing HR decreased (p < 0.01), while the LnRMSSD increased (p < 0.05) in all segments except for SleepStart. The Pearson correlations between relative changes in nocturnal and morning segments were − 0.11 to 0.72 (3000-m) and − 0.25 to 0.79 (OL). The OL response in Sleep4h HR and LnRMSSD correlated with the relative change in 3000-m time (r = 0.63, p = 0.001 and r=-0.50, p = 0.013, respectively). Conclusions: Nocturnal and morning HR and LnRMSSD correlated moderately or highly in the majority of cases during the BL, but their responses to intensive training were not similarly aligned, especially in LnRMSSD. The nocturnal segments seemed to be sensitive to physical loading, and their responses were associated with the performance-related training responses. Key Points: • Moderate-to-high correlations were found between nocturnal and morning assessments of HR and HRV during regular endurance training in recreational runners. • In their responses to maximum exercise, nocturnal and morning HR and HRV were not necessarily aligned, as nocturnal segments seemed more responsive to such a stimulus. • While lower HR and higher HRV were associated with better endurance performance in all recording segments, changes in these parameters after the overload period correlated only in nocturnal segments. [ABSTRACT FROM AUTHOR]

Background: Carers of people with Alzheimer's disease often have a high degree of commitment and dedication which may also compromise physical and emotional, leisure, and occupational self-care. This study aimed to explore health-related quality of life (HRQoL) and psychoemotional variables in caregivers with and without caregiver overload and its relationship. Methods: A single-measure cross-sectional correlational study was carried out involving 59 informal caregivers of people with Alzheimer's disease with a mean age of 59.30 (±10.58). The participants completed the adult HRQoL questionnaires (EQ-5D-3L), Zarit Burden Inventory test, General Happiness Questionnaire, Satisfaction with Life Scale, Rosenberg self-esteem scale, Occupational Balance Questionnaire (OBQ-E), International Fitness Scale (IFIS), Family Apgar scale, and Duke-UNC-11 Functional Social Support Questionnaire. Results: A significantly higher level of HRQoL (p = 0.029) in subjective happiness (p = 0.018), perceived social support (p = 0.046), avoidance (p = 0.034), occupational balance (p = 0.002), life satisfaction (p = 0.037), and self-perceived physical fitness (p = 0.021) was found in caregivers without perceived overload. Also, HRQoL was directly associated with self-perceived physical fitness (β = 0.534; p < 0.001) and occupational balance (β = 0.375; p < 0.001) and self-esteem (β = 0.249; p < 0.016). Conclusions: Caregivers who do not perceive overload have better levels of HRQoL and psychoemotional variables, establishing a relationship between HRQoL with self-perceived physical fitness, occupational balance, and self-esteem. [ABSTRACT FROM AUTHOR]

The new‐generation manned spacecraft employs a new recovery system of parachutes and airbags. In order to realize the effective cushion of the return capsule airbag, the conversion of the single‐point hanging to the double points for the spacecraft is necessary. In the conversion process, the long hanging rope and the height of the return capsule will cause a large impact and disturbance to the cabin, but the traditional dynamic modeling method is not suitable for those with complex boundary conditions. In order to solve these problems, a finite element model is proposed to analyze the suspension conversion process and simplify the parachute model based on the aerodynamic load dynamic matching control method to analyze the dynamic response characteristics, such as overload, speed, and force of the cabin, quantifying the conditions of the rope in the process. Results are generally consistent with experimental data. This study provides guidance for future optimization work and will greatly support the safe‐return technology of the new‐generation manned spacecraft. [ABSTRACT FROM AUTHOR]

Anchored slope with weak structural planes is a complex combination of rock mass and retaining structure, whose stability analysis is a necessary condition for road safety protection. To better understand the failure mechanism of anchored slope with weak structural planes under local overload, a series of physical model tests as well as corresponding numerical simulations have been conducted. Based on the test and numerical modeling results, the following conclusions are drawn: There is a serious stress concentration in the middle of the slope, which results in the failure of the slope surface in the shape of a bulge. Under the action of vertical stress, the anchored slope forms a wedge sliding zone along the weak structural plane. The overloading failure mode of the anchored slope with weak structural planes is collapse-upper extrusion-middle traction-lower, and the whole along the weak structural plane to the lower part of the wedge sliding failure. Overload changes the load bearing and deformation characteristics of anchored slope with weak structural planes. Additionally, the greatest stress occurs in the weak structural plane shear failure location, while the weak structural plane isolates the deformation and stress transfer. The axial force is distributed in the shape of “Z”, and the strength of the anchor cable in the middle and upper row should be appropriately strengthened. [ABSTRACT FROM AUTHOR]

Copyright of Journal of National University of Defense Technology / Guofang Keji Daxue Xuebao is the property of NUDT Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Background Resting heart rate (HR) and HR variability (HRV) are widely used parameters to assess cardiac autonomic nervous system function noninvasively. While resting assessments can be performed during sleep or after awakening, it would be relevant to know how interchangeable the results of these measurements are. This study aimed at examining the alignment between nocturnal and morning assessments during regular endurance training and in response to intensive training. A total of 24 recreational runners performed a 3-week baseline period (BL) and a 2-week overload (OL) period (Lucia’s training impulse + 80%). Their running performance was assessed with a 3000-m running test after the BL and OL. The participants recorded daily their nocturnal HR and HRV (the natural logarithm of the root mean square of successive differences; LnRMSSD) with a photoplethysmography-based wrist device and performed an orthostatic test (2-min supine, 2-min standing) every morning with a chest-strap HR sensor. The HR and LnRMSSD segments that were analyzed from the nocturnal recordings included start value (SleepStart), end value (SleepEnd), first 4-h segment 30 min after detected sleep onset (Sleep4h), and full sleep time (SleepFull). The morning segments consisted of the last-minute average in both body positions. All segments were compared at BL and in response to the 3000-m test and OL. Results All nocturnal HR and LnRMSSD segments correlated with supine and standing segments at BL (r = 0.42 to 0.91, p

Background: It remains unknown if flywheel-assisted squats can be reliably utilized to increase power outputs and if such outputs are related. Objectives: To compare assisted and unassisted flywheel squat peak power outputs, determine their reliability, and analyze the relationship of the delta difference between peak power outputs during the squats. Methods: Twenty male athletes attended the laboratory 6 times—performing 3 sets of 8 repetitions of assisted and unassisted squats during 2 familiarization sessions and then 3 sets of 8 repetitions during experimental sessions 3 to 6 (2 sessions for unassisted and assisted squat in randomized order, respectively). Results: Concentric and eccentric peak power were significantly greater during assisted squats (both P <.001, d = 1.59, d = 1.57, respectively). Rating of perceived exertion (P =.23) and eccentric:concentric ratio (P =.094) did not differ between squat conditions. Peak power measures obtained excellent reliability, while rating of perceived exertion and eccentric:concentric ratio estimates were rated as acceptable to good, with greater uncertainty. A large to very large correlation (r =.77) was found between concentric and eccentric peak power delta difference of assisted and unassisted squats. Conclusions: Greater concentric outputs during assisted squats induce greater eccentric outputs and obtain greater mechanical load. Peak power is a reliable metric for monitoring flywheel training, whereas the eccentric:concentric ratio should be used with caution. Eccentric and concentric peak power are strongly related during flywheel squats, evidencing the need to maximize the concentric output to enhance the eccentric output. [ABSTRACT FROM AUTHOR]

Abstract Since the early 1900s, repeated heat exposure has been used as a method to induce physiological adaptations that enhance our ability to tolerate heat stress during athletic and occupational pursuits. Much of this work has been dedicated to quantifying the time course of adaptation and identifying the minimum duration of acclimation required to optimise performance or enhance safety. To achieve this, investigators have typically applied classical (constant load) heat acclimation, whereby 60–90 min exercise is performed at the same absolute or relative intensity in a hot environment for 3–24 days, with adaptations evaluated using an identical forcing function test before and after. This approach has provided a foundation from which to develop our understanding of changes in thermoregulatory function, but it has several, frequently overlooked shortcomings, which have resulted in misconceptions concerning the time course of adaptation. It is frequently suggested that most of the thermoregulatory adaptations during heat acclimation occur within a week, but this is an oversimplification and a predictable artefact of the experimental designs used. Consequently, the time course of complete human adaptation to heat remains poorly understood and appears to vary considerably due to numerous individual factors. The purpose of this communication is to highlight the key methodological considerations required when interpreting the existing literature documenting adaptation over time. We also propose potential means by which to improve the way we induce and quantify the magnitude of adaptation to expedite discovery.

The single-peak overload test based on DIC technology was carried out in this study, and U71MnG steel was used to explore the influence of dislocation motion on crack propagation during overload. The changes in the shape and size of the plastic zone during the overload fatigue cycle are tracked and recorded, and the trends in the stress intensity factors of the Christopher–James–Patterson (CJP) and dislocation correction models are compared. The degree of influence of the dislocation motion on the variation in the stress intensity factors is evaluated, and the variation pattern of the plastic flow factor is derived (the amount of crack tip blunting, ρ). The results showed that the dislocation correction model increased the accuracy of the solution of the coefficient set, and the predicted size of the plastic zone of the correction model was more consistent with the experimental data. A better match with the crack tip was observed in the experimental plastic zone, the dislocation correction model error with the theoretical plastic zone fluctuates within 10%, whereas the CJP model can reach a maximum of 36.75%, demonstrating the insensitivity of the dislocation correction model. The plastic flow factor ρ follows the same pattern as that of the plastic zone area and stress intensity factor amplitude, ρ increases slowly with the increase of crack length before overload, ρ increases significantly after overload and then decreases sharply, and it recovers to be stable with the disappearance of the overload hysteresis effect of crack propagation. [ABSTRACT FROM AUTHOR]

Bone tissue is subjected to increased mechanical stress during high-intensity work. Inadequate bone remodeling reparability can result in the continuous accumulation of microdamage, leading to stress fractures. The aim of this work was to investigate the characteristics and repair mechanisms of tibial microdamage under several degrees of overload. Also, we aimed at better understanding the effects of overload on the multi-scale structure and mechanical properties of bone. Sixty 5-month female rats were divided into three groups with different time points. Micro-CT was used to evaluate the three-dimensional microstructure, and three-point bending, quasi-static fracture toughness and creep mechanical test were carried out to evaluate the mechanical properties. SEM was used to observe the morphological characteristics of fracture surfaces. Section staining was used to count the microdamage parameters and numbers of osteoblasts and osteoclasts. The microarchitectures of cancellous and cortical bones in the three overload groups showed different degrees of damage. Overload led to a messy crystal structure of cortical bone, with slender microcracks mixed in, and a large number of broken fibers of cancellous bone. The properties associated with the elastic plasticity, fracture toughness, and viscoelasticity of cortical bone reduced in three groups, with that corresponding to day 30 presenting the highest damage. The accumulation of microdamage mainly occurred in the first 14 days, that is, the crack density peaked on day 14. Peak-targeted bone remodeling of cortical and cancellous bones occurred mainly between days 14 and 30. The influence of overload mechanical environment on bone quality at different time points was deeply investigated, which is of great significance for the etiology and treatment of stress fractures. [ABSTRACT FROM AUTHOR]

Since the early 1900s, repeated heat exposure has been used as a method to induce physiological adaptations that enhance our ability to tolerate heat stress during athletic and occupational pursuits. Much of this work has been dedicated to quantifying the time course of adaptation and identifying the minimum duration of acclimation required to optimise performance or enhance safety. To achieve this, investigators have typically applied classical (constant load) heat acclimation, whereby 60–90 min exercise is performed at the same absolute or relative intensity in a hot environment for 3–24 days, with adaptations evaluated using an identical forcing function test before and after. This approach has provided a foundation from which to develop our understanding of changes in thermoregulatory function, but it has several, frequently overlooked shortcomings, which have resulted in misconceptions concerning the time course of adaptation. It is frequently suggested that most of the thermoregulatory adaptations during heat acclimation occur within a week, but this is an oversimplification and a predictable artefact of the experimental designs used. Consequently, the time course of complete human adaptation to heat remains poorly understood and appears to vary considerably due to numerous individual factors. The purpose of this communication is to highlight the key methodological considerations required when interpreting the existing literature documenting adaptation over time. We also propose potential means by which to improve the way we induce and quantify the magnitude of adaptation to expedite discovery. [ABSTRACT FROM AUTHOR]

In short track speed skating, there is asymmetric fatigue of the gluteus maximus (GM) muscle resulting from the technique of skating. Scientific reports confirm the relationship between muscle fatigue and its change in the slope frequency of bioelectrical activity. To investigate whether athletic experience in elite short track speed skating can distinguish the asymmetry change in slope frequency of the raw electromyographic signal (EMG) of the GM muscle, influenced by the disparity in experience between junior and senior athletes. In the research, an elite group of short track speed skating national team athletes Junior and Senior, participated. Isometric tension GM muscle was tested using the Biering-Sorensen test. The study confirmed differences in the asymmetry of slope frequences EMG signal in GM muscle between juniors and seniors in short track speed skating (p⩽ 0.001). Senior athletes showed greater slope frequences in the right GM muscle (p⩽ 0.002), while juniors showed greater in the left GM muscle (p⩽ 0.008). Intergroup analysis revealed significantly meaningful differences (p⩽ 0.001) in the level of slope frequences of the right GM muscle (juniors vs. seniors), highlighting the asymmetry resulting from experience. Statistically significant differences in the level of slope frequences of the right gluteus maximus muscle juniors vs. seniors were demonstrated, suggesting asymmetry due to experience and skating technique. [ABSTRACT FROM AUTHOR]

To improve soccer performance, coaches should be able to replicate the match's physical efforts during the training sessions. For this goal, small-sided games (SSGs) are widely used. The main purpose of the current study was to develop similarity and overload scores to quantify the degree of similarity and the extent to which the SSG was able to replicate match intensity. GPSs were employed to collect external load and were grouped in three vectors (kinematic, metabolic, and mechanical). Euclidean distance was used to calculate the distance between training and match vectors, which was subsequently converted into a similarity score. The average of the pairwise difference between vectors was used to develop the overload scores. Three similarity (Simkin, Simmet, Simmec) and three overload scores (OVERkin, OVERmet, OVERmec) were defined for kinematic, metabolic, and mechanical vectors. Simmet and OVERmet were excluded from further analysis, showing a very large correlation (r > 0.7, p < 0.01) with Simkin and OVERkin. The scores were subsequently analysed considering teams' level (First team vs. U19 team) and SSGs' characteristics in the various playing roles. The independentsample t-test showed (p < 0.01) that the First team presented greater Simkin (d = 0.91), OVERkin (d = 0.47), and OVERmec d = 0.35) scores. Moreover, a generalized linear mixed model (GLMM) was employed to evaluate differences according to SSG characteristics. The results suggest that a specific SSG format could lead to different similarity and overload scores according to the playing position. This process could simplify data interpretation and categorize SSGs based on their scores. [ABSTRACT FROM AUTHOR]

During some trail running races, athletes have to carry hydration support, food, and technical and safety equipment, which generates an additional load that must be mobilized during the race. The aim of the present study was to determine the physiological responses to overload running and the effect they may have on metabolic zones. Seventeen well-trained male trail runners (n = 17) completed three maximal treadmill tests with weighted vests at 0%, 5%, and 10% of their body mass (L0, L5, and L10). Their gas exchange was monitored to assess their ventilatory thresholds 1 (VT1) and 2 (VT2), maximal fat oxidation zone (FatMax), and peak oxygen consumption (VO2peak). Their heart rate (HR), power, and velocity (V) were tracked to compare their behavior. One-way ANOVA showed significant differences in the V (p < 0.001; ηp2 = 0.4620) as a limitation for reaching the peak velocity (Vpeak), with a significant decrease in the Vpeak with the L10 compared to the L0 (p = 0.002) and L5 (p = 0.004). In addition, one-way ANOVA showed significant differences in the peak absolute power (p < 0.001; ηp2 = 0.468) among the groups, detecting higher power production between the L10 and L0 (p < 0.001) and between the L10 and L5 (p = 0.015). Loads higher than L5 could generated important physiological and mechanical modifications, while a load of L5 managed to maintain the working conditions without overloading. These insights shed light on nuanced strategies for optimizing performance and endurance, offering valuable considerations for athletes seeking to enhance their training regimens during overload conditions. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the internal training loads of a professional Spanish female futsal team throughout 26 weeks of training including preseason and in-season weeks and verify the impact of training period and/or training load magnitudes on heart-rate variability responses. Furthermore, we aimed to assess, intraindividually, the relationship between training load and the coefficient of variation (CV) of weekly natural log of the root mean square difference of successive normal interbeat (RR) intervals (lnRMSSDCV), obtained from ∼5 measures per week, and recorded in the seated position. Methods: A within-subject design involved 12 high-level outfield female futsal players (mean [SD] age: 23.9 [3.4] y). Results: lnRMSSD was significantly lower and lnRMSSDCV was significantly higher during the preseason (weeks 1–6) compared to in-season (weeks 7–26) (P <.001). Individually, players presented moderate to large negative correlations between lnRMSSDCV and lnRMSSD during the 26 weeks of observation. Correlations ranged between rplayer4 = −.41 (95% CI, −.69 to −.02) and rplayer12 = −.55 (−.78 to −.18). Players also presented moderate to verylarge positive correlations between lnRMSSDCV and session rating of perceived exertion. Correlations ranged between rplayer7 =.41 (.04 to.71) and rplayer1 =.71 (.45 to.86). Conclusion: Professional female futsal players in this study presented increased lnRMSSD and reduced lnRMSSDCV during 20 weeks into the competitive season compared to 6 weeks of preseason. Furthermore, lnRMSSDCV was negatively associated with lnRMSSD on an intraindividual basis. Finally, higher internal training loads were positively correlated with lnRMSSDCV, indicating that heart-rate variability is responsive to weekly training loads. [ABSTRACT FROM AUTHOR]

Considering the anisotropy of microstructure of additive manufactured metal materials, quantitative assessment of the anisotropy of fatigue crack growth (FCG) behavior is necessary for structural damage tolerance design and evaluation. This study conducted an experimental and mechanistic investigation of the FCG behavior of the laser metal deposited (LMD) Ti–6Al–4V alloy, focusing on the anisotropy of FCG and the effect of overload on FCG. Both the FCG experiments with constant amplitude loading (CAL) and with a single overload (OL) were performed in different directions. Under CAL, the FCG rate exhibits a bilinear correlation with the stress intensity factor. Before the transition point (ΔKT = 16.9 MPa√m), since the grain boundaries are sparser along the columnar crystal growth direction, the FCG rate in the XY specimen is higher than that in the other directions. When the FCG rate further increases, the hindrance effect of grain boundaries on FCG weakens, and the anisotropy of FCG rates disappears. An interesting new finding is that when an overload is applied after ΔKT, the FCG rates in the XZ and ZX directions become different, and the overload-induced anisotropy increases with the overload ratio (OLR). The difference in FCG rates between the two directions exceeds 23.2% when OLR is 2.5. Based on microscopic and theoretical analysis, it was demonstrated that the overload induces residual strain in front of the crack-tip and enhances FCG resistance. The FCG resistance is positively related to the size of the plastic zone and negatively related to the yield strength in the loading direction.

Existing studies have proved that interfaces between the prefabricated layer and the cast‐in‐place layer significantly affect the static performance of prefabricated concrete structures using the wet connection method, but little has been known about the fatigue performance, especially at high load levels. This study investigated the fatigue behavior of prefabricated composite concrete beams under negative bending moment induced by the high‐stress level cyclic load. Fifteen composite T‐beams with three different designed sections were tested. The failure mode, cracking and deflection behavior, steel strain development, and the new‐old concrete interfacial deformation were recorded and analyzed. It was found that the stress redistribution occurred with the debonding cracks generated at the new‐old concrete interface, causing the degradation of the static and fatigue performance. Setting interfacial shear keys could prevent such debonding failure at static and low cyclic loading levels. Meanwhile, the corresponding mechanisms were verified through cross‐sectional analysis. [ABSTRACT FROM AUTHOR]

AISI 440C is a high carbon martensitic stainless steel with superior wear and abrasion resistance among all grades of stainless steel. Hydraulic amplifier valve (HAV) spools, made of AISI 440C stainless steel, are used in flow control devices of launch vehicle actuator systems. In the present case, a failure occurred near the undercut region of the HAV spool during the vibration test. The failure was observed specifically at M5 threaded region of the spool. A detailed investigation has been carried out to understand the root cause of the failure. 612 µm deep pit was observed with corrosion products on the fracture surface near to the undercut region of M5 thread. Elemental chemical composition analysis via energy-dispersive X-ray spectroscopy (EDS) confirmed the presence of oxygen and chlorine in the pit location. Primary carbides exposed to the rough machined surface at the undercut region lead to the pit initiation and propagation because of the galvanic potential difference between matrix and primary carbides. Failure of the HAV spool is attributed to corrosion-assisted overload. [ABSTRACT FROM AUTHOR]

The mining industry is a sector that plays an important role in the Indonesian economy. One of the crucial heavy equipment in mining operations is a hauler or transport truck, such as the HD 785-7 unit. Overload on the HD 785-7 hauler occurs when the load being transported exceeds the maximum capacity permitted by the manufacturer's specifications. This condition not only reduces fuel efficiency, but also poses a significant risk to the structural and mechanical integrity of the hauler. This research aims to reduce the frequency of overloads on the HD 785-7 hauler unit at PT Putra Perkasa Abadi Site MIP Lahat through implementing the Early Alarm Indicator system. Overloading a hauler can cause damage to components such as suspension and reduce operational performance. With this early alarm system, operators are expected to be more responsive to overload conditions, thereby increasing operational efficiency and reducing repair costs. The research results showed a decrease in overload frequency by 21% and an increase in the average load observed to 102.10 tons after system implementation. It is recommended to implement the Early Alarm Indicator system on all HD 785-7 hauler units at PT Putra Perkasa Abadi. [ABSTRACT FROM AUTHOR]

To investigate whether tibiofemoral alignment influences early knee osteoarthritis (OA). We hypothesized that varus overload exacerbates early degenerative osteochondral changes, and that valgus underload diminishes early OA. Normal, over- and underload were induced by altering alignment via high tibial osteotomy in adult sheep (n = 8 each). Simultaneously, OA was induced by partial medial anterior meniscectomy. At 6 weeks postoperatively, OA was examined in five individual subregions of the medial tibial plateau using Kellgren-Lawrence grading, quantification of macroscopic OA, semiquantitative histopathological OA and immunohistochemical type-II collagen, ADAMTS-5, and MMP-13 scoring, biochemical determination of DNA and proteoglycan contents, and micro-computed tomographic evaluation of the subchondral bone. Multivariate analyses revealed that OA cartilaginous changes had a temporal priority over subchondral bone changes. Underload inhibited early cartilage degeneration in a characteristic topographic pattern (P ≥ 0.0983 vs. normal), in particular below the meniscal damage, avoided alterations of the subarticular spongiosa (P ≥ 0.162 vs. normal), and prevented the disturbance of otherwise normal osteochondral correlations. Overload induced early alterations of the subchondral bone plate microstructure towards osteopenia, including significantly decreased percent bone volume and increased bone surface–to–volume ratio (all P ≤ 0.0359 vs. normal). The data provide high-resolution evidence that tibiofemoral alignment modulates early OA induced by a medial meniscus injury in adult sheep. Since underload inhibits early OA, these data also support the clinical value of strategies to reduce the load in an affected knee compartment to possibly decelerate structural OA progression. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As usually presented, octagons of opposition are rather complex objects and can be difficult to assimilate at a glance. We show how, under suitable conditions that are satisfied by most historical examples, different display conventions can simplify the diagrams, making them easier for readers to grasp without the loss of information. Moreover, those conditions help reveal the conceptual structure behind the visual display. [ABSTRACT FROM AUTHOR]

Based on numerical simulation within the framework of a two-dimensional axisymmetric problem of continuum mechanics, an analysis has been made of penetration into a semi-infinite barrier by dummy strikers with diameters of 14 and 18 mm and an initial velocity of 1200 m/s with and without account for the effects of the detachable sabot used for accelerating the dummies in the barrel of a ballistic installation. In simulating the penetration by dummy strikers in a sabot, a reduction was registered in the depth of penetration by a little over 10% with increase in the maximum overload compared to the case of penetration in the absence of a sabot. A cause has been identified for the sabot′s negative effects on dummy strikers′ penetration, lying in an increase of tangential stresses acting on the surface of the dummies′ contact with the adjacent layer of loosened concrete due to precompression of this layer by the sabot until the sabot′s complete detachment from the dummy striker. [ABSTRACT FROM AUTHOR]

We aimed to analyze whether women with higher family-role overload regret sacrificing their professional work to fulfill family responsibilities better after analyzing the costs of making the work sacrifice. In Study 1, participants (n = 218 women and men) self-reported their family-role overload, rated the costs of sacrificing their work for their family, and rated the extent to which they experienced regret about this sacrifice. In Study 2, participants (n = 285 women) reported their gender role ideology and responded to the same measures as in Study 1. In Study 3, participants (n = 180 women) reported their ideology and their partner's perceived gender role ideology and completed the same procedure as in Study 1. The main findings showed that women (but not men) with higher family-role overload perceived more costs of sacrificing their work for the family, which were associated with greater regret about making the sacrifice. Additionally, women who perceived a traditional ideology in their partner reported more family-role overload, which was associated with greater costs of making the work sacrifice, which in turn was related to greater experienced regret. These findings indicate that although women make these sacrifices based on societal expectations in accordance with their gender role, they could not have obtained the results they could have expected and consequently could regret risking their professional progress for the family. In addition, they suggest that partner involvement is also necessary to overcome this invisible gender inequality. [ABSTRACT FROM AUTHOR]

Copyright of Salud Uninorte is the property of Fundacion Universidad del Norte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Parents of children with neuromuscular diseases experience multiple difficulties in their daily lives that affect their physical and psychological health. The risk factors for these health issues have not been sufficiently investigated. Therefore, the aim of this study was to analyze the potential predictors of overload in these parents, including QoL, somatic symptomatology, life satisfaction, psychological adjustment and certain sociodemographic variables. Methods: A cross-sectional research study was conducted among parents who are caregivers for children with NMD in Spain. A convenience sample of 110 parents who were contacted by associations and hospitals was used. Variables were evaluated using the sociodemographic questionnaire, CarerQol-7D, PHQ-15, Barthel Index, Psychological Adaptation Scale, Zarit Overload Scale and Satisfaction with Life Scale. Results: One of the most relevant findings of the present study is the identification of 3 overload groups (mild to moderate, moderate to severe, and severe overload) based on life satisfaction and somatic symptom scores within the predictive model of the discriminate analysis. Wilk's lambda of the discriminant function was 0.568, χ² (2, n = 55) = 8.815, p < 0.001. Discussion: This study presents a model that reveals the influence of unemployment, having a child with a severe level of dependency, the presence of somatic symptomatology and life satisfaction on caregiver overload. Likewise, the caregiver's self-esteem could be a protective factor against overload. [ABSTRACT FROM AUTHOR]

Copyright of Aydin Dental Journal is the property of Aydin Dental Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To examine the stress distribution in the maxillary All-on-4 treatment concept supported by implants of different diameters under two different loading forces using finite element analysis. Materials and Methods: Two distinct All-on-4 designs were prepared in a fully edentulous maxilla, supported by 3.3- and 4.1-mm-diameter implants. Posterior implants were tilted distally, approximately 30 degrees to the occlusal plane, and anterior implants were placed axially. Bone, implant, and prosthetic components were modeled separately and were tightly connected to each other. Under two distinct loading conditions representing the occlusal forces of healthy and bruxist individuals, the stresses on peri-implant bone, implant, and prosthetic components were evaluated using finite element analysis. Results: There were higher stresses on cortical bone than on trabecular bone. The stresses on bone and implant components were concentrated around the posterior implants, whereas stresses on the prosthesis were concentrated anteriorly. With increasing implant diameter, the stresses on trabecular bone, abutments, and crowns increased, whereas the stresses on cortical bone, implants, and frameworks decreased. Compressive stresses in the cortical bone and von Mises stresses in the frameworks exceeded the overload limit in both models under bruxist loading. Conclusion: The stresses on the cortical bone, implants, and frameworks were slightly higher in the model with 3.3-mm-diameter implants, whereas the stresses on the trabecular bone, abutments, and crowns were slightly higher in the model with 4.1-mm-diameter implants. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to examine some of the benefits and drawbacks of communication visibility. Specifically, building on communication visibility theory, the authors study how and why message transparency and network translucence may increase knowledge reuse and perceived overload through behavioral responses of vicarious learning and technology-assisted supplemental work. Design/methodology/approach: Drawing on survey data obtained from 1,127 employees of a global company operating in the industrial machinery sector, the authors used structural equation modeling to test the hypothesized model. Findings: The results demonstrate that the two aspects of communication visibility yield somewhat differential benefits and drawbacks in terms of knowledge reuse and communication overload, through vicarious learning and supplemental work practices. Research limitations/implications: The results demonstrate the relationship between different aspects of communication visibility and knowledge reuse, specifically through vicarious learning. Furthermore, the findings highlight a potential drawback of visibility – communication overload – specifically through technology-assisted supplemental work. Overall, network translucence seems more beneficial compared to message transparency in terms of knowledge reuse and communication overload. Originality/value: The study connects with recent work on communication visibility by distinguishing differential direct and indirect effects of message transparency and network translucence. It also extends this work by testing relationships between communication visibility and a potential drawback of visibility – communication overload – specifically through technology-assisted supplemental work.

Purpose. The article is devoted to the creation of traction motor protection by modern methods and means based on a programmable logic controller (PLC). Methodology. To simulate motor fault monitoring in laboratory conditions, magnetic field and temperature sensors were installed on a small powerful induction motor, and then the data obtained from the sensors in normal and overloaded motor modes were analyzed. Based on the research, protection methods were developed. Findings. Previously used simple motor protection systems based on components such as timers, contactors, electromagnetic switches, voltage and current transformers were slow and inaccurate, and had low sensitivity. However, the production of PLCs and their application in this industry has eliminated these problems. The intensive operation of motors as the main executive equipment requires the creation of modern automated protection systems to ensure their reliable and stable operation. Originality. The paper improves the method of protection of traction motors based on the use of programmable logic controllers. In addition to the voltage and current parameters, the proposed method involves monitoring the magnetic field. It also provides for the possibility of adjusting the protection response time. As a result, in the event of overload, short circuit, and other non-standard situations, the improved method provides the system with the ability to make more accurate and reliable decisions. Practical value. The TIA Portal software package has modeled a traction motor protection system by temperature and current and considered its practical application. To make such systems more effective, in the future, comprehensive protection systems based on the diagnostic state of the traction motor can be developed. In addition, an effective system can be created by providing SCADA control of the engines of several vehicles simultaneously.

Stable operation of wastewater plants under overload has been a hot spot of concern for researchers，and efficient nitrogen and phosphorus removal is a difficult point in the process of stable operation. A wastewater treatment plant in Zhengzhou uses a pre-anoxic modified A2/O process，treating 1.2-1.8 times the design value，with influent BOD5/COD，BOD5/TN and BOD5/TP ranges of 0.19-0.88，1.38-7.21 and 13.12-89.17 respectively，and uses multi-point distribution of influent，increased internal reflux ratio，precise aeration and other operation methods. The variation of nitrogen and phosphorus in the whole wastewater process was analyzed. The results showed that the removal rates of COD，TN and TP reached 90.4%，83% and 98.55%，which were better than the Class Ⅰ A discharge standard of the Pollutant Discharge Standard for Urban Wastewater Treatment Plants（GB 18918—2002）， when the influent water was evenly distributed in the pre-anoxic，anaerobic and anoxic sections，the internal return ratio was 400% and the DO concentration in the aerobic tank was below 0.5 mg/L.Some indicators reached Surface Water Quality Standard（GB 3838—2002） Class Ⅲ standard.

This document is an editorial that emphasizes the importance of reporting negative results in exercise research. It discusses how these results can provide valuable insights into molecular targets for adaptation. The document also highlights five articles within the research topic that cover different aspects of exercise, including the effects of chemotherapy on exercise responses, the impact of treadmill training on muscle cellular content and transcriptional changes, the effects of Apolipoprotein E on muscle regeneration, the role of lactate in muscle growth, and the indicator of DNA damage after exercise. These articles contribute to the development of exercise prescription guidelines and provide important information for understanding muscle plasticity. The document is a collection of articles that explore various molecules and signaling mechanisms involved in the adaptive response to exercise, covering topics such as muscle inflammation, muscle recovery and growth, and mitochondrial function. The authors hope that the information presented in these articles will aid other researchers in furthering their understanding of the complex processes involved in the body's response to exercise. [Extracted from the article]

Evidence shows that older users have lower performance levels for IT-enabled tasks than younger users. This is alarming at a time when the workforce is rapidly aging and organizational technologies are proliferating. Since the explanation for these lower performance levels remains unclear, managers are not sure how to help older users realize their full potential as contributors to organizational success. The research model presented here identifies the declining information-processing speed of older workers as the cause of their reduced capacity to perform IT-enabled tasks. According to the model, IT experience and IT self-efficacy reduce the negative impacts of this decline, whereas IT overload and the effort cost of IT use aggravate them. To test the model, data were collected using three complementary studies. The results supported the model and indicated five ways that organizations can help older users improve their capacity to perform IT-enabled tasks. Additional data collected in interviews with human resources directors confirmed the relevance of these solutions. [ABSTRACT FROM AUTHOR]

Context: Running is a popular sport globally. Previous studies have used a gait retraining program to successfully lower impact loading, which has been associated with lower injury rates in recreational runners. However, there is an absence of studies on the effect of this training program on the plantar pressure distribution pattern during running. Objective: To investigate the short-term effect of a gait retraining strategy that uses visual biofeedback on the plantar pressure distribution pattern and foot posture in recreational runners. Design: Randomized controlled trial. Setting: Biomechanics laboratory. Participants: Twenty-four recreational runners were evaluated (n= 12 gait retraining group and n= 12 control group). Intervention: Those in the gait retraining group underwent a 2-week program (4 sessions/wk, 30 min/session, and 8 sessions). The participants in the control group were also invited to the laboratory (8 times in 2 wk), but no feedback on their running biomechanics was provided. Main Outcome Measures: The primary outcome measures were plantar pressure distribution and plantar arch index using a pressure platform. The secondary outcome measure was the foot posture index. Results: The gait retraining program with visual biofeedback was effective in reducing medial and lateral rearfoot plantar pressure after intervention and when compared with the control group. In the static condition, the pressure peak and maximum force on the forefoot and midfoot were reduced, and arch index was increased after intervention. After static training intervention, the foot posture index showed a decrease in the foot pronation. Conclusions: A 2-week gait retraining program with visual biofeedback was effective in lowering rearfoot plantar pressure, favoring better support of the arch index in recreational runners. In addition, static training was effective in reducing foot pronation. Most importantly, these observations will help healthcare professionals understand the importance of a gait retraining program with visual biofeedback to improve plantar loading and pronation during rehabilitation. [ABSTRACT FROM AUTHOR]

Adequate nursing care can be decisive for the outcome of a patient admitted to an internal medicine ward. Individual prediction of nursing activity at the time of a patient's admission could improve the work process. This study aimed to assess the objectively assessed nursing requirements of patients admitted to a medical setting and to identify clinical factors that correlate with high demands. This is a prospective and pragmatic observational study that enrolled patients admitted to the Internal Medicine ward at the Altovicentino Civil Hospital (Italy) between September 1 and December 31, 2022. Nursing activities were recorded for the first 3 days of hospitalization and standardized as performance/5 min/patient. Patients requiring more than the 75th percentile of performance/5 min/patient were considered nursing over-activities. Multivariable models were used to assess patient-related risk factors associated with nursing over-activity. This study enrolled 333 patients (mean age: 74.2; 55.6% male). Their mean Charlson Comorbidity Index (CCI), Clinical Frailty Scale (CFS), Chronic Barthel Index, and Sistema Informtativo della Performance Infermieristica (SIPI) scores were 5.3, 4.2, 62.4, and 53.7, respectively. Mean National Early Warning System (NEWS) on admission was 3.9 (standard deviation: 2.8). A median of 73 (interquartile range [IQR]: 54–109) nursing care activities/5 min/patient were performed. NEWS score (odds ratio [OR]: 1.372, 95% confidence interval [95%CI]: 1.216–1.547, p < 0.001) and Acute Barthel Index (OR: 0.983, 95%CI: 0.967–0.999, p = 0.041) were independent risk factors for nursing over-activities. NEWS and the Acute Barthel Index could help reorganize nursing resources within internal medicine wards, allowing for an equal distribution between patients who require more resources and those who require less. [ABSTRACT FROM AUTHOR]

Dangerous or illegal driving may disrupt the traffic safety management of public security organs, damage road infrastructure, lead to traffic accidents, or result in economic losses. This paper proposes a framework based on China's highway toll data to identify dangerous or illegal driving risks, such as unfamiliarity with road conditions, overload, driving over the speed limit, fatigued driving, fake license plates, and other risks. The unfamiliarity with road conditions is identified with the frequency of driving routes. When the total weight of a vehicle and its cargo is greater than the upper limit of the total weight of the vehicle and its cargo, the vehicle can be judged as overloaded. When the actual travel time is less than the minimum travel time, it can be inferred that the vehicle has a risk of fatigued driving, driving over the speed limit, a fake license plate, or other risks. Two accidents are used to demonstrate the process of the proposed framework for identifying driving risks based on China's highway toll data. Additional analysis proves that the proposed framework can be used to identify dangerous or illegal driving risks, and it provides a scientific basis for the traffic safety management of public security organs, reducing infrastructure damage, and avoiding the loss of national taxes and fees. [ABSTRACT FROM AUTHOR]

Inflatable aerodynamic decelerators (IADs) are designed to slow down the speed of a spacecraft or payload during its descent through an atmosphere. As part of evaluating the structural integrity of an inflatable aerodynamic decelerator assembly in the stowed condition, a spin test was conducted revealing a significant failure within the aluminum alloy AA2014 stem component. Before this failure, an initial test was successfully conducted, rotating at 3 revolutions per second (rps) for 60 s, with no observable issues at the weak tie location of the IAD. Subsequently, a second test was planned, involving a higher spin rate of 6 rps for a duration of 200 s. During the second test, as the spin rate gradually increased from a static condition to 5.8 rps, a significant failure noticed at the top stem, precisely at the flange-to-shaft interface. A detailed metallurgical analysis was carried out on the failed components to delve into the nature and underlying causes of this failure. Microstructure and microhardness analysis indicate that material is in proper heat treatment condition. Examination of the fracture surface revealed the presence of equiaxed dimple features, along with shallow elongated shear dimples, indicating a failure mechanism driven by a combination of shear and tensile overload. The failure is attributed to the higher load experienced at the shaft–flange interface due to the spinning and wobbling of the IAD assembly at elevated rps. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Induction motors are widely used in industries as well as some home appliances. It is therefore necessary to provide protection from likely sources of faults such as overcurrent, overvoltage, under voltage and high temperature. The continuous and intensive use of squirrel cage induction motors in modern industry has in some cases caused a serious deterioration of the electrical insulation in the windings of the machine, generating internal short-circuit failures. Early detection of the fault is essential due to technical and economic issues. The classical method of protecting induction motors from faults involves the use of timers, contactors, and voltage and current relays. Simulation of fault detection is observed using DVPSS2 series PLC with the ISP Soft and DOP Soft software. The results are validated using the hardware experimental setup including voltage, current relays with contactors and auxiliary relays. The method is highly reliable in protection of motor for various conditions. [ABSTRACT FROM AUTHOR]

The power communication network carries various power services to ensure the safe operation of the power network, among which, the relay protection service is the most important service. Reasonable planning of the service route can improve the effectiveness and reliability of data transmission in the power communication network, thereby ensuring the reliable operation of the power grid. This paper constructs a route planning architecture for the power communication network based on a software-defined network. On this basis, parameters such as the power service and network-carrying service status are defined. With the goal of minimizing network risk variance and considering link bandwidth utilization and overload constraints of relay protection services, a service route allocation problem has been raised. To solve this problem, a power service route planning scheme based on a reinforcement learning algorithm is proposed. This algorithm uses the state–action–reward–state–action (SARSA) algorithm to complete service route planning. The simulation results show that using the route planning scheme proposed in this paper can avoid the overload of relay protection services, reduce network risk variance, and effectively balance network risk. [ABSTRACT FROM AUTHOR]

Healthcare must provide an appropriate response to individual and family needs, engaging the community, promoting shared responsibility, and aligning existing resources with citizen requirements. Individuals in situations of dependency often rely on family caregivers, necessitating family adjustments and specific training to fulfil the caregiver role. The present study aimed to analyse the relationship between satisfaction with social support and the burden on informal caregivers. This observational study employed a cross-sectional, quantitative, and descriptive-correlational approach. Data collection was conducted through a questionnaire. A total of 51 informal caregivers participated in the study. Of these caregivers, 78.4% were women, 29.4% had a medium/low level of education, and 52.9% assumed the role of informal caregiver for five or more years. We observed some level of burden in 80.4% of informal caregivers, with a more significant impact on those who had assumed the caregiver role for approximately 1-2 years. The most sought-after support involved social support for economic assistance (76.5%) and caring for the family member (49%). The study highlights the importance of nurses implementing interventions to enhance caregivers' knowledge, promote health literacy regarding social support, and facilitate group dynamics, allowing informal caregivers to share experiences and navigate situational transitions. [ABSTRACT FROM AUTHOR]

The road use load should essentially conform to the plan load as stated in the design guidelines. But in reality, the load received by the road is more than standard, so it has the potential to accelerate road damage. This study aims to predict the increase in the value of the International Roughness Index (IRI) and model the increase in value (IRI) due to overload. The approach method used in the analysis is the prediction of an increase in the IRI value due to excess load. The data collection method is carried out on road sections which include IRI values, vehicle load testing, CBR values and environmental conditions. The location of data collection is carried out on BTS Provincial Road. Surabaya City – Legundi. The analysis method for the prediction of the IRI value is the HDM-4 method, while to model the prediction of the increase in the IRI value is used exponential method with various parameters related to the results. The prediction results show that overload affects the increase in the IRI value. From the initial IRI value of 2.37, if the road is traversed by vehicles with standard loads for 20 years, the IRI value increases to 10.42. While the road traveled by overloaded vehicles within 20 years from an IRI value of 2.37 will increase to 16.88. With overload, the IRI value increases very sharply with the exponential model y = 2.3583e0.0982x . While the standard load by generating an exponential model y = 2.3825e0.0739x . From the results of the exponential model, load overload resulted in a significant increase in the IRI value with a growth rate of 0.0982. When compared to normal expenses which only experienced a growth rate of 0.0739. The modeling results show that overload will increase the growth of very high IRI values with the exponential model increase graph. [ABSTRACT FROM AUTHOR]