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A finite-element (FE) investigation into the response of integral abutment bridges (IABs) to seismic loading in the longitudinal direction was conducted. An example multi-span reinforced concrete solid-slab bridge was designed and analysed using an elasto-plastic two-dimensional FE model. The bridge abutment was taken as supported on steel H-piles. The proposed FE model was found to have the capability of simulating both the bridge construction and the backfilling process using a multi-step numerical process. The bridge was examined considering various lengths and different backfill materials, and was subjected to earthquake loading. The analyses showed that the seismic response of IABs is notably affected by the bridge length. Longer bridges may be subject to higher pressures on the abutments and internal forces in the bridge structure. The stiffness and strength parameters of the backfill material may also markedly influence dynamic pressures on the abutments and internal forces in the structure. Backfill materials with greater stiffness and strength parameters may cause significant reductions in the seismic flexural stresses in both the abutments and the deck. Coupling seismic and thermal loads could be suggested for the design of IABs.

According to recent data, many bridges tend to fail due to seismic inadequacy in design. Circular piers are more effective in reducing scour depth and increasing the durability of bridges than an elliptical bridge pier. The question is “whether circular pier performs better under seismic action than elliptical pier or not”. So a comparative study was conducted to analyze the behavior of circular and elliptical piers under earthquake forces, and complete nonlinear static pushover analysis was carried out for two different bridge models separately. Pushover curve data from Indian Standard Code was used to formulate the problem and performance outcomes of the bridges were analyzed. It was found that single circular pier showed no failure and better performance in both directions of the bridge, with more displacement capacity than double elliptical piers when subjected to incremental lateral loads. The design capacity (D/C) ratio in the longitudinal direction was 1.8 times more for single circular pier bridge and in the transverse direction, the ratio was 1.4 times more for double elliptical pier bridge for the considered earthquake situation. Results also showed 47% less drift value for single circular pier bridge compared to double elliptical pier bridge.

BACKGROUND: Hamstring flexibility plays a significant role in physiotherapy. Various stretching studies have been conducted to increase hamstring flexibility, but the effects of the Fascial Distortion Model (FDM) on hamstring flexibility have not yet been investigated. Moreover, no studies have compared the effects of FDM and static stretching. OBJECTIVES: To investigate the effects of the FDM on hamstring flexibility compared with static stretching. METHODS: Thirthy healthy adults were divided into two groups: static stretching and FDM groups. Static stretching was performed to hamstring in the supine position. The FDM was performed using trigger band techniques that followed the hamstring in a longitudinal direction. Hamstring flexibility was measured using the active knee extension angle (KEA), passive straight leg raising (SLR), sit-and-reach (SR), and finger-floor distance (FFD) tests. A paired t-test and an independent t-test were performed to compare the hamstring flexibility measurements. RESULTS: Both groups showed significant differences (p< 0.05) in KEA, SLR, SR, and FFD before and after. However, no significant difference (p> 0.05) was found between the two groups. CONCLUSIONS: There was no difference in the effects of FDM and static stretching on hamstring flexibility.

In order to repair an osteochondral defect, it is critical to advance a bi-lineage constructive scaffold with gradient transition. In this study, we developed a simple and straightforward approach for fabricating a multidomain gel scaffold through the assembly/disassembly of low-molecular-weight gels (LMWGs) inside a stable PEGDA network by photopolymerization. The versatility of this technology enabled to vary biological, topological, and mechanical properties through material selection and to generate a chondrogenic-osteogenic gradient transition. The multidomain gel exhibited an increasing stiffness gradient along the longitudinal direction from the cartilage layer at approximately 20 kPa to the bone layer at approximately 300 kPa as well as spatial variation at the gradient interface. Moreover, the transitional layer with a condensed structure and intermediate stiffness prevented delamination of the contrasting layers and maintained microenvironmental differences in the upper and lower layers. The in vitro results indicated that each domain had an individual capacity to spatially control the differentiation of MSCs toward osteoblastic lineage and chondrocytic lineage. This was mainly because the mechanical and topographical cues from the respective domains played an important role in modulating the Rho-ROCK signaling pathway, whereas the blockage of ROCK signals significantly impaired domain-modulated osteogenesis and enhanced chondrogenesis. Additionally, the quantity and quality of osteochondral repair were evaluated at 4 and 8 weeks through histological analysis and micro-computed tomography (micro-CT). The results indicated that the multidomain gels distinctly improved the regeneration of subchondral bone and cartilage tissues. Overall, the outcomes of this study can motivate future bioinspired gradient and heterogeneity strategies for osteochondral tissue regeneration. Statement of significance The regeneration of osteochondral defects remains a major challenge due to the complexity of osteochondral structure and the limited self-repair capacity of cartilage. The gradient designs to mimic the transition between the calcified cartilage and subchondral bone plate as well as the zones of cartilage are an effective strategy. In this study, the controlled multi-domain gels were fabricated though the assembly/disassembly of low molecular weight gels inside the stable PEGDA network by photopolymerization. The prepared multi-domain gels presented a chondrogenic-osteogenic gradient transition, which decreased the possibility of delamination and stimulated the osteochondral tissue regeneration in vivo. Overall, our study can inspire new strategies of bioinspired gradients and heterogeneities for more challenging applications.

Ultrasound was considered as a means for determining mechanical properties of clear wood in six different Acacia mangium provenances from a trial forest planted in Vietnam. A total of 30 trees (5 trees from each provenance) with no major defects were selected, and a 50-cm-long log was obtained at 1.3 m above the ground from each tree for the assessment of mechanical properties. The measured average ultrasound velocities for provenances tested in the longitudinal direction ranged from 4094 m/s to 4271 m/s. The predicted average dynamic modulus of elasticity (Ed) values varied from 7.42 GPa to 8.70 GPa among provenances. The Ed indicated significant positive correlation coefficients with modulus of elasticity (0.64 to 0.96), modulus of rupture (0.44 to 0.87), and compression strength (0.54 to 0.92) for provenances examined in this study. The results indicated that the use of ultrasound was feasible to determine the mechanical properties of A. mangium provenances planted in Vietnam.

In the project of Hong Kong-Zhuhai-Macau Bridge, the back-silting of natural foundation section is serious, and the tunnel structure is prone to uneven settlement along the longitudinal direction, ...

During long-term observations, the Borok and College Geophysical Observatories have registered ultralow-frequency (ULF) electromagnetic signals from remote earthquakes. We have analysed the characteristics of such signals that occur several minutes before a seismic event. Our analysis shows that the dynamic spectra of the signals from earthquakes that occurred in different regions are similar, although the earthquakes differ in magnitude and focal depth. We investigate and discuss daily and seasonal probabilities for the occurrence of ULF electromagnetic pulses. Attention is given to the uneven distribution of their sources (i.e. earthquakes) on the earth’s surface. Our study shows that the ULF electromagnetic signals are clustered in separate zones and cells. When mapped, these clusters mark seismic electromagnetically active regions. In the northern hemisphere, a maximum cluster is found at latitudes 30–45°. In the longitudinal direction, two maximum clusters are located in the western sector. They are considered as the major and additional peaks (latitudes 120–150° and 0–30°, respectively). Examples are given to illustrate earthquake precursors in various regions. Based on the analysis results, we conclude that the occurrence of ULF electromagnetic pulses before earthquakes is universal. These pulses need to be investigated in a more detail to clarify if an upcoming earthquake is detectable from such signals a few minutes before its occurrence, and whether it is possible, in principle, to use this information for safety alerts before seismic shaking arrives.

Highlights • 1 min time reduction for prostate patient setup using SGRT. • Accurate initial positioning for deep-seated target with surface imaging. • Improved workflow using intuitive color map for setup guidance., Introduction The aim of this study was to evaluate if surface guided radiotherapy (SGRT) can decrease patient positioning time for localized prostate cancer patients compared to the conventional 3-point localization setup method. The patient setup accuracy was also compared between the two setup methods. Materials and methods A total of 40 localized prostate cancer patients were enrolled in this study, where 20 patients were positioned with surface imaging (SI) and 20 patients were positioned with 3-point localization. The setup time was obtained from the system log files of the linear accelerator and compared between the two methods. The patient setup was verified with daily orthogonal kV images which were matched based on the implanted gold fiducial markers. Resulting setup deviations between planned and online positions were compared between SI and 3-point localization. Results Median setup time was 2:50 min and 3:28 min for SI and 3-point localization, respectively (p

Osteoporosis (OP), a skeletal disease making bone mechanically deteriorate and easily fracture, is a global public health issue due to its high prevalence. It has been well recognized that besides bone loss, microarchitecture degradation plays a crucial role in the mechanical deterioration of OP bones, but the specific role of microarchitecture in OP has not been well clarified and quantified from mechanics perspective. Here, we successfully decoupled and identified the specific roles of microarchitecture, bone mass and tissue property in the failure properties of cancellous bones, through μCT-based digital modeling and finite element method simulations on bone samples from healthy and ovariectomy-induced osteoporotic mice. The results show that the microarchitecture of healthy bones exhibits longitudinal superiority in mechanical properties such as the effective stiffness, strength and toughness, which fits them well to bearing loads along their longitudinal direction. OP does not only reduce bone mass but also impair the microarchitecture topology. The former is mainly responsible for the mechanical degradation of bones in magnitude, wherever the latter accounts for the breakdown of their function-favorable anisotropy, the longitudinal superiority. Hence, we identified the microarchitecture-deterioration-induced directional mismatch between material and loading as a hazardous feature of OP and defined a longitudinal superiority index as measurement of the health status of bone microarchitecture. These findings provide useful insights and guidelines for OP diagnosis and treat assessment.

Background. In last decades, the number of babies born preterm has increased significantly. Premature newborns are more susceptible to cardiovascular disease in the long-term. To identify subclinical myocardial impairment in premature infants, an assessment of of the left ventricle (LV) deformation could be used.Objective. The aim of the study was to study the left ventricle (LV) Longitudinal Strain of the endocardial, middle and epicBardial layers in children born with very low and extremely low body weight, at the age from one to five years.Design and methods. The study included 88 children aged from one to 5 years old, born very premature with very low and extremely low body weight. The comparison group consisted of 43 healthy children of the same age, born full-term. The LV Longitudinal Strain of the endocardial, middle and epicardial layers was studied using the Speckle Tracking Imaging-2D Strain.Results. In children aged 1 to 5 years, born with very low and extremely low body weight, changes in the gradient of transmural wall Strain and a decrease in LV segments longitudinal strain were detected in 15.90 % and 14.77 % of cases, respectively. Mothers of children born prematurely and who subsequently registered disturbance of the transmural gradient of left ventricular strain in 10 cases (71.43 %) had a history of threatened termination of pregnancy. The threat of termination of pregnancy was noted in all women whose children had a decrease in LV segmental strain. In children who have normal of LV segmental strain, the threat of termination of pregnancy in mothers was registered in 16 cases (26.23 %). LV remodeling is observed in children with a change in the gradient of transmural wall strain or and with a decrease in LV longitudinal segment strain. Conclusion. Changes in the transmural gradient of wall deformation or reduction of segmental LV deformation in the longitudinal direction in premature infants require correction of the conventional algorithm of dispensary observation in an outpatient setting.

Automatic vehicle following is an important feature of a fully or partially automated highway system (AHS). The on-board vehicle control system should be able to accept and process inputs from the driver, the infrastructure, and other vehicles, perform diagnostics, and provide the appropriate commands to actuators so that the resulting motion of the vehicle is safe and compatible with the AHS objectives. The purpose of this article is to design and test a vehicle control system in order to achieve full vehicle automation in the longitudinal direction for several modes of operation, where the infrastructure manages the vehicle following. These modes include autonomous vehicles, cooperative vehicle following, and platooning. The vehicle control system consists of a supervisory controller that processes the inputs from the driver, the infrastructure, other vehicles, and the onboard sensors and sends the appropriate commands to the brake and throttle controllers. In addition, the controller makes decisions about normal, emergency, and transition operations. Simulation results of some of the basic vehicle following maneuvers are used to verify the claimed performance of the designed controllers. Experiments on Interstate-15 that demonstrate the performance of the throttle controller with and without vehicle-to-vehicle communications in an actual highway environment are also included.

The tensile strength along the longitudinal direction of unidirectional carbon fiber reinforced plastics (CFRPs) constitutes important data for the reliable design of CFRP structures. Our earlier reports proposed the formulations for the statistical static, creep, and fatigue strengths of CFRP based on Christensen’s model of the viscoelastic crack kinetics. This study is concerned with the statistical assessment of the tensile static, creep, and fatigue strengths of unidirectional CFRPs by using the proposed formulations and the characterization of the long-term strengths of unidirectional CFRPs. First, the proposed formulations for the time-dependent and temperature-dependent statistical static, creep, and fatigue strengths of CFRP are introduced. Second, the tensile static, creep and fatigue strengths of unidirectional CFRP are measured statistically at various temperatures using resin-impregnated CFRP strands as tensile test specimens by measuring the viscoelasticity of the matrix resin. Finally, the master curves showing the long-term life of these strengths are constructed by substituting these measured data into the formulations. The results clarify that the formulations are applicable with high reliability over wide ranges of time and temperature for the statistical tensile static, creep and fatigue strengths of unidirectional CFRP except above the glass transition temperature of the matrix resin. Therefore, the fatigue strength degradation phenomena of unidirectional CFRPs can be expressed by the time- and temperature-dependent part due to the viscoelastic behavior of the matrix resin and the number of load cycle-dependent parts. The long-term life prediction of unidirectional CFRPs under static, creep and fatigue tension loadings can be determined by ascertaining the mechanical properties of the CFRP and matrix resin in the proposed formulations.

The soil temperature distribution characteristics were experimentally studied, during heat storage and release processes in the fine-grained sand with different moisture content. Results showed that, the soil temperature distributions in the process of soil heat storage and release are almost symmetric under the same excess temperature. The excess temperature is the main factor affecting the soil temperature change, and the influence of the moisture content variation is almost negligible. At each set of excess temperature, the soil temperature change in heat storage and release processes have a good logarithmic relationship with the heat transfer time, radial distance and longitudinal distance. The soil temperature change shows a linear increase trend with the excess temperature, and the soil temperature disturbance in radial direction is far greater than that in longitudinal direction. Based on the hypothetical multivariate nonlinear power function regression model, the experience formula for predicting the soil temperature was proposed. The prediction deviation was within 10 %.

Locally adapted properties within a machine component offer opportunities to increase the performance of a component by using high strenght materials where they are needed. The economic production of such hybrid components on the other hand represents a major challenge. The new tailored forming process chain, which is developed within the collaborative research center (CRC 1153) represents a possible solution to produce hybrid components. This is made possible by the use of pre-joined hybrid semi-finished products made from two different steel alloys, which are subsequently formed. The semi-finished products can be manufactured for example by means of deposition welding. Due to a thermal mechanical treatment, an overall higher component strength of the joining zone can be achieved. The deposition welding processes can be used to generate a cladding on a base material. During the welding, one of the most difficult tasks is to reduce the amount and size of pores in the joining zone. These pores can reduce the strength in the joining zone of the welded parts. However, additional pores can occur in the intermediate zone between the substrate and the cladding. In the presented study, the influence of the forming process on the closing of pores in the cladding and in the intermediate zone was investigated. Therefore, cylindrical specimen were extracted in longitudinal direction of the welding track by wire-cut eroding. These welding tracks are manufactured by plasma-transferred arc welding of AISI 52100 on a base plate made of AISI 1015. Further, specimens were prepared transversely, so that the base material, the intermediate layer, and the welded material are axially arranged in the specimen. The prepared specimen were checked for pores by means of scanning acoustic microscopy. Subsequently, an uniaxial compression test was carried out with various degrees of deformation and the two specimen designs were examined again for pores. A microstructure analysis was carried out after each step. The investigations show that there is a need for a minimum degree of deformation to reduce pores in the welded material. However, this required plastic strain cannot be achieved in the welded material of the hybrid specimen, which is a result of the homogeneous temperature distribution in the specimen. The homogeneous temperature distribution leads to different flow properties in the specimen, which means that the main plastic deformation is taking place in the base material.

Estimation of muscle passive force from elasticity using shear wave elastography (SWE) has been reported. However, the relationship between the elasticity and passive force of human muscles has not been elucidated. This study investigated the elastic modulus–passive force relationship in human skeletal muscles at multiple sites. Four rectus femoris (RF) muscles were dissected from a human Thiel-embalmed cadaver. Calibration weights (0–600 g in 60-g increments) were applied to the distal tendon via a pulley system, and the shear elastic modulus as an index of elasticity was measured using SWE. The shear elastic modulus of the RF was measured at the proximal, central, and distal portions. The results demonstrated that the relationships between the elasticity in the longitudinal direction of the muscle and the passive force were nearly linear for all tested sites, with coefficients of determination ranging from 0.813 to 0.993. Shear wave elastography may be used as an indirect method to measure the changing passive force at any site within human muscles.

The fatigue limit of the transverse direction was obtained remarkably (125 MPa) lower than that of the longitudinal direction. The fatigue anisotropy was related to different characteristics of inc...

In the composite structure of a concrete-filled steel tube (CFST), because the concrete is concealed inside the steel tube, subsurface cavities can occur and are difficult to identify. In this study, a thermal-driven method based on Brillouin fiber-optic sensors (BFOSs) was proposed to quantitatively identify subsurface cavities in CFSTs. By performing a thermodynamic analysis of subsurface cavities in CFSTs, a thermal model related to the relationship between the subsurface cavity size and the temperature rise at the top surface of the CFST was established for the first time. Then, a sensing scheme based on the BFOS was proposed, and its feasibility was evaluated through an experimental program. The experimental program involved the use of an active heating layer for inputting heat flow into the CFST structure and BFOSs for the distributed measurement of temperature to identify subsurface cavities in CFSTs. The experimental results indicated that the BFOSs can achieve real-time distributed measurements of the surface temperature of the CFSTs. According to the temperature anomalies in the temperature rise curves of the CFSTs, the subsurface cavities can be accurately located in the longitudinal direction of the CFST, and its length can be quantified. There is an obvious linear relationship between the temperature rise and the square root of the heating time, from which the equivalent heat absorption coefficient (EHAC) can be determined. Furthermore, according to the relationship between the subsurface cavity height and the EHAC in the thermodynamic theoretical analysis, the subsurface cavity height can be obtained quantitatively.

Presented are the results of mechanical tensile tests of longitudinal (segmental) samples cut from the midsection of claddings spent as VVER-1000 FA during one- and six-year campaigns and subject to thermal tests in helium at 480 °С during 468 full days. An average burnup of these fuel rods achieved ~ 20 and ~ 70 (MW·day)/kg U, respectively. The tests followed the examinations for cladding mechanical properties performed using the tests results for ring samples cut from the specified fuel rods. These fuel rods were tested in the experiments to determine impact of long-term thermal tests that model dry storage conditions on mechanical properties of Zr E110 claddings. Based on mechanical tests results at room temperature and at 380 °С there was determined as follows: ultimate strength sв, yield strength s0,2 and total relative elongation d0 of claddings length-wise on the fuel rod segments at the fuel column midsection. The obtained characteristics were compared to corresponding values for initial (unirradiated) cladding tubes and mechanical test results of the ring samples in the transverse direction. Long-term thermal tests have led to partial return to initial (before operation) values sв, s0,2 and d0 of radiation-hardened claddings; this return was more prominent in the longitudinal direction than in the transverse one. A radiation hardening decrease was accompanied with an increase in total relative elongation values in both cladding directions. Anisotropy of yield strength has changed as well. These changes can be explained by partial annealing of radiation defects, which are obstacles to dislocation movements during cladding strain. The morphology of above radiation defects is different in various sliding planes in texturized grains of cladding material.

Highlights This article focuses on the tensile properties of sugarcane leaves. The moisture content and sheath diameter were selected as test factors, and the test index was the stalk-leaf connecting force. The load-displacement curves of stalks and leaves were plotted. Two-way ANOVA was also discussed. Abstract . The tensile properties of sugarcane leaves are critical factors affecting the harvesting quality of sugarcane harvesters. Thus, it is important to investigate the tensile properties of sugarcane stalks and leaves. The selected test factors were leaf moisture content and sheath diameter, and the stalk-leaf connecting force was selected as test index. The tests were conducted with two moisture content levels of 15% and 20%, and three sheath diameters of 22, 26, and 30 mm. The stress-strain curves of stalks and leaves were plotted to show how the tensile force varied during the tensile test. The results showed that there was a strong linear correlation between the stalk-leaf connecting force and diameter of leaf sheath, and the connecting force also increased with the increasing moisture content. In addition, leaf tensile forces in longitudinal direction were much larger than in transverse direction. Two-way ANOVA revealed that both of the moisture contents (A) and sheath diameters (B) had significant effects on the stalk-leaf connecting force (p < 0.01), however, the interaction between A and B was not significant (p > 0.1). This study provides a theoretical reference for the design and improvement of crop dividers of sugarcane harvester. Keywords: Moisture content, Sheath diameter, Stalk-leaf connecting force, Sugarcane leaves, Universal testing machine, Tensile properties.

Polymers have effectual applications in many industrial branches. Especially in the automotive and food industry polymers are frequently applied. Thermoplastics can be used also including the transport of specific liquids. This study deals with an investigation of the mechanical properties of polyethylene film made of low-density polyethylene (LD-PE), which has a low density and high degree of chain branching. LD-PE film was exposed to chemical influences of selected liquid media (Savo disinfection, Savo Saponate, and Coca-Cola) for three months. Those media have a different value of potencia hydrogeni (pH). Degradation of mechanical properties of LD-PE film by selected media was monitored. Using tensile test important parameters: σB, eB and E for polymers were evaluated. After exposure, those values of parameters increased in comparison with values of original LD-PE film in the longitudinal direction. The increase of tensile stress at break (σB) in comparison with original LD-PE film was as following: for Savo disinfection - increase of 83.43 %, Savo Saponate - increase of 68.60 %, and Coca-Cola - increase of 67.63 %. In the transversal direction, the exposure in media has a different impact on investigated parameters. The increase of tensile stress at break (σB) in comparison with the original LD-PE film was as following: for Savo disinfection - increase of 14.06 %, and Savo Saponate - increase of 33.02 %. For Coca-Cola was recorded a reduction of 36.90 % in comparison with original LD-PE film. Savo disinfection and Savo Saponate have the most suitable influences on the mechanical properties of LD-PE film for the transport of those liquids after three months.

The article consists information about feasibility of foamed polyethylene based materials for a seamless thermal insulation sheath. Foamed polyethylene with and without metallized coating were used for examination. The formation of a seamless sheath is carried out by connecting individual sheets into a lock with subsequent welding of the lock joints with hot air. The strength of the weld is the defining durability characteristic of an insulating seamless sheath. The tensile strength in the longitudinal direction for products with a metallized coating is 80–92 kPa, without a metallized coating – 80–87 kPa, and for a weld joint – 29–32 kPa. The performance characteristics of insulation sheath based on foamed polyethylene meet the requirements for materials and systems operating at negative and alternating temperatures while having low vapor permeability. The features of the implementation of insulation systems in the construction of frame and frameless buildings in agriculture are also described.

This paper explores the analysis of sound speeds in the longitudinal direction and their reduction to the reference moisture content w = 12 %. The sound speed cw was determined with Sylvatest Duo device. Moisture content of beech sawmill assortments (round timber: N = 16, logs: N = 2 × 16, structural boards: N = 54) in the range of 12 – 72 % was measured. For the analysis purposes, the sound speed was converted to reference conditions (c12, uref = 12%). A second-degree polynomial (parabola) with a regression equation of the form: c// = 5649 - 27,371 × w + 0.0735 × w2 was used to convert cw to c12, and correction of measured and calculated values was used as well. The sound speeds c12 in sawmill assortments (c12,round, c12,log, c12,board) were evaluated by linear dependences. Dependence was not confirmed for c12,round and c12,board1 (r = 0.168), in contrast for c12,round and c12,log2 the dependence is statistically very significant (r = 0.634). The results of testing showed that the most suitable procedure for predicting quality of structural timber is the first step round timber – log2, the second step: log2 - board2. More exact results of the construction boards were obtained from log2 than from log1. The sound speed is used in the calculation of dynamic modulus of elasticity (Edyn). EN 408 mentions the possibility of using dynamic modulus of elasticity as an alternative method in predicting the quality of structural timber.

The differences between temperatures in the animal occupied zone (AOZ) and temperatures measured by control system sensors are rarely explored. This experimental study quantifies the dry-bulb air temperature [hereinafter temperature] distribution inside a finisher pig building that combines natural ventilation through automatically controlled openings with a mechanical ventilation system. Year-long temperature data from 28 sensors located at 3 different heights in the building was analysed to help understand the temperature distributions and indicate the temperatures below or above an assumed optimal temperature range, defined as between 14 °C and 24 °C. Relatively large variations in the spatial temperature distribution were found, and they were higher in the vertical direction than in the longitudinal direction. The temperatures measured in the AOZ at 0.25 m height, were on average, 7 °C warmer than that at 1.5 m height. The AOZ temperature correlated better with temperatures measured at 0.7 m or 1.5 m height in the same pen than with temperatures measured in the AOZ at other pens. The analyses show that a proportional–integral based control system effectively counteracts the effects of outdoor wind conditions, and the control system is capable of maintaining the defined optimal temperature at the measurement height. However, the optimum temperatures at the measurement heights above AOZ do not correspond to the measured temperatures in the AOZ.

الملخص أثر خواص أقمشة بطانة حقيبة اليد النسائية على کفاءة أداء الحياکة يهدف البحث الحالى إلى التعرف علي أهم المشکلات التى تواجه حياکة أقمشة بطانة حقيبة اليد النسائية، مع تحديد تأثير الخواص الطبيعية والميکانيکية لأقمشة البطانة المستخدمة في إنتاج حقائب اليد النسائية على کفاءة أداء حياکتها والتوصل إلي المعايير الصحيحة للوصول إلي منتج ذو جودة عالية. وتکونت عينة البحث من ثلاثة أنواع من خامات البطانة (شمواه - ساليا – داکرون)‏ المستخدمة في تبطين حقائب اليد النسائية وأثر أختلاف (نوع الحياکة- نمرة الإبرة – نمرة الخيط) على کفاءة أداء حياکتها في الاتجاه الطولي والاتجاة العرضي، وإشتملت أدوات البحث على الأجهزة الخاصة بالاختبارات المعملية للخواص الطبيعية والميکانيکية لخامات البطانة، إستبيان موجه لمصنعي حقائب اليد لمعرفة مشکلات حياکتها. وتوصلت الدراسة بالنسبة لخامة البطانة الشمواة أن متوسط قوة شد وصلة الحياکة العادية والحياکة المتراکبة في الاتجاه الطولي والاتجاه العرضي بإستخدام إبرة ‏‏(110) أعطت أفضل النتائج لقوة شد الحياکة، کما تبين تفوق خيط 40/3 لقوة شد وصلة الحياکة العادية والحياکة المتراکبة لوصلات حياکة البطانة الشمواه في الاتجاه الطولي والاتجاه العرضي. أما بالنسبة لخامة البطانة الساليا أن متوسط قوة شد وصلة الحياکة العادية والحياکة المتراکبة في الاتجاه الطولي والاتجاه العرضي بإستخدام إبرة ‏‏(100) أعطت أفضل النتائج لقوة شد الحياکة، کما تبين تفوق خيط 60/3 لقوة شد وصلة الحياکة العادية والحياکة المتراکبة لوصلات حياکة البطانة الساليا في الاتجاه الطولي والاتجاه العرضي. أما بالنسبة لخامة البطانة الداکرون أن استخدام إبرة (110) أعطت أعلى قوة شد لوصلات الحياکة العادية والمتراکبة فى الاتجاه الطولى والحياکة المتراکبة فى الاتجاه العرضى، وأما فى الاتجاه العرضى للحياکة العادية نجد أن استخدام إبرة (100) أعطت أفضل النتائج لقماش بطانة الداکرون، مع تفوق أن خيط ‏‏40/3 لنوع الوصلة الحياکة العادية والمتراکبة فى الاتجاه الطولى والحياکة العادية فى الاتجاه العرضى، وأما فى الاتجاه العرضى للحياکة المتراکبة نجد أن استخدام خيط 60/3 أعطى أفضل النتائج لقماش بطانة الداکرون بالنسبة لقوة شد حياکة خامة الداکرون. Abstract ‎ “The impact of the properties of women's handbag lining fabrics on the efficiency of sewing performance” This research aims at identifying the most important problems facing the sewing fabrics of women's handbag lining, as well as identifying the impact of the natural and mechanical properties of the lining fabrics used in the production of women's handbags on the efficiency of their sewing performance and thus reaching the sound standards with the aim to obtain a high-quality product. The sample of the research consisted of three types of lining materials (Chamois - Saliya - Dacron) which are used in lining women's handbags and the impact of different (sewing type - needle number - thread number) on the efficiency of their sewing performance in the longitudinal direction and the transverse direction was explored. The instruments of the research included the laboratory devices tests of the natural and mechanical properties of lining materials, and a questionnaire directed to handbag manufacturers to find out their sewing problems. Regarding the chamomile lining material, the study concluded that the average tensile strength of ordinary sewing and the overlapping sewing in the longitudinal direction and the cross direction using a needle no. (110) gave the best results for the tensile strength of sewing. It was also concluded that the thread of 40/3 showed the superiority of the tensile strength of ordinary sewing and the overlapping sewing of Chamois lining sewing connections is in the longitudinal and the transverse direction. As for the Saliya lining material, the average tensile strength of the ordinary sewing connection and the sewing thread in the longitudinal direction and the cross direction using a needle no. (100) gave the best results for the tensile strength of sewing. It was also concluded that the thread of 60/3 showed the superiority of the tensile strength of the ordinary sewing connection and the overlapping sewing for Saliya lining sewing in the longitudinal and transverse directions. As for the material of Dacron lining, the use of needle no. (110) gave the highest tensile strength for ordinary and overlapping sewing connections in the longitudinal direction and the overlapping sewing in the transverse direction, while, in the transverse direction of ordinary sewing, we find that the use of needle no.(100) gave the best results for the Dacron lining fabric, with superiority of the thread 40/3 for the type of ordinary sewing and overlapping sewing in the longitudinal direction ,and the ordinary sewing in the transverse direction, while , in the transverse direction of overlapping sewing, we find that using a thread of 60/3 gave the best results for the Dacron lining fabric regarding the tensile strength of the Dacron fabric.

Currently, no theory is available to describe the conformation of DNA confined in a channel when the nanochannel diameter is around the persistence length. Back- folded hairpins in the undulating wormlike chain conformation result in the formation of loops, which reduces the stretch of the molecule in the longitudinal direction of the channel. A cooperativity model is used to quantify the frequency and size of the loop domains. The predictions agree with results from the Monte Carlo simulation.

Canadian Nuclear Laboratories has an on-going Research & Development program to support the development of a scaled–down 300 MWe version of the Canadian Super-Critical Water Reactor concept. The 300 MWe and 170–channel reactor core concept uses low enriched uranium fuel and features a maximum cladding temperature of 500 °C. Our goal is to test surface-modified zirconium alloys for use as fuel cladding. Zirconium alloys are attractive as they offer low neutron cross section thereby allowing the use of low enriched fuel. In this paper, we report on the results of general corrosion experiments used to evaluate chromium-coated zirconium-based alloys in the two chemistries (630 μg/kg O2 in both de-aerated and lithiated supercritical water). These experiments were conducted in a refreshed autoclave at 500 °C and 23.5 MPa. After exposure, the weight gain and the hydrogen absorption were examined. At adequate coating thickness, longitudinal and transverse coupons show similar corrosion behavior with improved corrosion resistance compared to uncoated coupons. The measured concentrations of hydrogen absorption are higher for the transverse coupons. Alkaline treatment resulted in higher weight gains than was found in pure oxygenated supercritical water.

Important investments have been made worldwide in the modernization and construction of railway lines. Plans for new constructions, have also been laid out. Recently, precast concrete has been widely employed in the construction of railway bridges and viaducts. Several precast solutions have been applied, namely: I-shaped or U-shaped precast girders and uni-cellular or bi-cellular precast box girders. Regarding the structural scheme in the longitudinal direction, either simple span or continuous decks have been used. In this context, this work aims to contribute to the knowledge about the real performance of these structures through the development of a laboratory tests setup, for the study of this type of structure, focusing on the connection between the precast beams. The setup will be implemented at the Laboratory of Earthquake and Structural Engineering (LESE), several experimental campaigns on the cyclic behaviour of reinforced concrete elements have been carried out. 6612-034D-AE05 | PEDRO DA SILVA DELGADO N/A

Evolution of tensile properties in 8-mm-thick AA2219-T8X plates with the pre-artificial aging (here onward termed pre-age) cold work applied independently by cold rolling and stretching was monitored by tensile tests. It is shown that the desired minimum 0.2% proof stress (0.2% PS) of 352 MPa, ultimate tensile strength of 441 MPa and percentage elongation of 7 in T87 temper could be achieved in the longitudinal direction of the alloy following 6% of pre-age cold work by stretching. However, these minimum tensile properties could be achieved in both longitudinal and long transverse directions following 7% of pre-age cold work independent of the methods by which the cold work is employed. The tensile strength properties subsequently decreased when the percentage of pre-age cold work equaled or exceeded 8%. The coarsening of θ′ (metastable Al2Cu-θ) precipitates caused the decrease in strength. It is further observed that suitable percentages of pre-age cold work involving both cold rolling and stretching not only provide the minimum desired T87 tensile properties but considerably reduce the differences in 0.2% PS values between longitudinal and long transverse directions of the plates. This is discussed in terms of the tendency of the pre-age cold work by stretching to introduce directional properties in the plates.

Connected and automated vehicles (CAVs) show great potential to improve both traffic efficiency and safety by sharing information. This paper addresses the problem of coordinating two strings of vehicles at highway on-ramps efficiently and safely in the longitudinal direction. A rule-based adjusting algorithm is proposed to achieve a near-optimal merging sequence for vehicles coming from the mainline and entering through the ramp. Optimality analysis indicates that the proposed method performs very well compared with the global optimal solutions. Furthermore, to investigate the effectiveness and robustness of the proposed method, simulation-based case studies are carried out under both balanced and unbalanced scenarios. The results are compared with two other control strategies (i.e., rule-based methods and optimization-based methods) in terms of throughput, delay, computational cost, and fuel consumption.

El uso de grupos (o paquetes) de barras presenta ventajas tales como la descongestión de barras. Sin embargo, el empalme de este tipo de barras requiere de mayor detalle tanto en el despiece como en la ejecución. El empalme más habitual en este tipo de barras es el empalme por solape (o traslapo), escalonando las barras individuales en la dirección longitudinal. El Eurocódigo 2 y la ACI-318-14 difieren en las formas de empalme por solape y en la longitud de solape necesaria. En esta nota técnica los autores analizamos la tolerancia mínima existente en función de los tipos de solape en paquetes de barras.

Fast walking and jogging are two common exercises for people to maintain health in daily life. But the differences in loading patterns of fast walking and jogging are still unclear. The purpose of this study was to compare loading patterns in fast walking and jogging at the same speed, and to identify how differences in foot mechanics influence plantar pressure distribution between the two modes of gait. Totally, 49 healthy males participated in this study. Data of pressure parameters, including maximum force (MF), peak pressure (PP), contact area (CA), force-time integral (FTI), were recorded by Pedar-X insole plantar pressure measurement system in participants’ fast walking and jogging process at 7 km/h. A Load transfer analysis method was used to quantify the plantar load transference from fast walking to jogging. The results showed that MF, PP and CA increased in metatarsal regions and midfoot regions while decreased in toes regions and heel during jogging when compared with fast walking. FTI decreased in all foot regions during jogging compared to fast walking. Under the effects of spring mechanics and the varus of rearfoot during jogging, fast walking and jogging reveal different loading patterns. Compared jogging to fast walking, load transferred as follow: 1) in transverse direction, load transferred from lateral foot to medial foot in metatarsal regions and midfoot regions, 2) in longitudinal direction, load transferred from toes to the metatarsal, and from heel to the metatarsal and midfoot. These results also provide suggestions for footwear designs. Graphical abstract: [Figure not available: see fulltext.]. © 2020, The Author(s)., National Natural Science Foundation of China, NSFC: 11502154

NO2 sorption ability of cedar (Cryptomeria japonica) timbers was evaluated using a new measuring system that was developed in our previous study. Four drying conditions were applied, namely natural drying and three kinds of kiln-drying at 45, 60, and 105 °C. Aeration experiments were conducted using discoid specimens which had a thickness in the longitudinal direction of 1.5 mm, and a diameter of 10 mm. The moisture content was conditioned to 0 or 9 ± 1.0% in each drying condition. As a result, the NO2 sorption ability declined as the drying temperature increased. Based on the analysis of extractives, it was shown that the extractives content had a high correlation with the contribution ratio of extractives in the NO2 sorption volume of the specimens that were dried below 60 °C. Therefore, it was elucidated that the specimen dried naturally has the greatest NO2 sorption ability. Furthermore, the result of the gas chromatography–mass spectrometry (GC/MS) indicated that abietadiene influenced the NO2 sorption ability. Also, the NO2 sorption volume was high especially at the initial stage, which is higher under the condition with moisture.

Rolling-cut shearing is commonly used for side trimming of heavy steel plates. The standard shape for the upper blade is circular. However, this standard shape may cause variations of the lateral process force and thus an unintended lateral displacement of the upper blade. The results are quality defects of the sheared edges. These defects are unevenness in longitudinal direction with peak-to-peak values of more than 2 mm, extended fracture zones, and excessive burr near the beginning and end of the periodic cut (cut-transition point). So far, there is a lack of investigations and countermeasures for these quality defects. Therefore, the current paper aims at avoiding or significantly reducing these common edge defects just by optimizing the shape of the upper blade of rolling-cut shears. The optimized shape should ensure straight and even edges. The feasibility of this idea was analyzed on an industrial rolling-cut trimming shear of AG der Dillinger Huttenwerke, Dillingen, Germany, by comparing cuts from its nominal blade with cuts from the optimized blade. In these experiments, the peak-to-peak values of the unevenness was reduced by more than 80%. The proposed optimization of the blade geometry is easily transferable to other rolling-cut trimming shears.

The causes of deformation in the zone of welded joints are considered. Authors experimentally studied changes in hardness on the rolling surface of the rail in the longitudinal and transverse profiles within the thermally affected zone of the welded joint. It is established that the hardness of the rolling surface of the rail in the longitudinal direction in the thermally affected zone of the joint is uneven and is determined by the structures arising from the effects of the thermal cycles of welding and the quality of the local heat treatment. In this case, two "low spots" are clearly traced with a decrease in hardness to 290...300 HB and with a higher hardness up to 350 HB right in the welded joint. Experimentally investigated the change in the depth of the welded joint from the implemented tonnage. At the same time with strain gauge method, using the force method developed by N. N. Kudryavtsev, continuous changes in vertical forces when the wheels move along the welded joint zone were recorded. Average values of vertical forces from loaded cars were established. Experimental distributions of vertical forces were approximated by theoretical laws according to the Kolmogorov — Smirnov matching criterion. Recommendations are given on minimizing the harmful impact of rolling stock on the track in areas of lowering welded joints.The following conclusions were made.1. Geometry of the joint irregularity is in the form of a W-shaped deformation with an influx of metal on the receiving rail and lowering on the directing rail. The width of the upper part of the deformation varies between 160...200 mm along the axis of the rail.2. Deformation zone of the welded joint is a source of increased dynamic impact from the wheels of the rolling stock on the elements of the upper track structure. According to the results of experimental studies it was found that the greatest increase in dynamic effects was observed from locomotive wheels up to 45.. . 70 kN, maximum values reached 180...210 kN, from the wheels of loaded freight cars the values of vertical forces increased by 35.. .45 kN, maximum values reached 145...170 kN, from the wheels of empty cars increase dynamic impacts amounted to 14...16 kN, maximum values reached 32...36 kN.

The multicoloured tracer fibre technique has been used to study the helix twist in concentric cylindrical zones and along the length of fibre of ring spun yarn at different level of yarn extension....

The purpose of this study is to investigate the interrelationship of how the ship's wave resistance performance changes with the change of the longitudinal position of the section line in the ship's lines, and to find a way to use it in the hull-form design. To this end, we developed a hull-form automatic change algorithm that can maintain the proper hull-form while moving the section lines in the longitudinal direction, and the computer program for a numerical analysis was developed to apply the developed algorithm. By applying the developed hull-form automatic change algorithm and the wave resistance performance prediction program, the numerical analysis package was constructed. The numerical analysis was carried out for the passenger ship. Numerical analyzes were carried out by moving the section lines of the passenger ship in the longitudinal direction, and the results were compared with each other. Based on the numerical results, we attempted to investigate the correlation between the section line movement and the wave resistance performance.

The Advancements in Construction in terms of aesthetics and appeal has led to a need of creating spaces with more compact and convenient designs. There is a hierarchy of load transfer for a building. The changes in weight of any preceding member will change the dimensions of succeeding members in the hierarchy. The reduction in the self-weight of beam due to introduction of a hollow section changes the flexural behaviour and the shear behaviour of the beam and also makes it economical section. There is also the advantage of reduction in the depth of beam giving more floor space to user. This paper focuses on Comparative study of Conventional beam and RC beam strengthened with Mild Steel Pipe Section/Mild Steel Box Section. The Composite Section is obtained by embedding Reinforced Concrete beam with MS Pipe/Box Section in Longitudinal Direction. Load – deflection behaviour of conventional beam and RC beam with MS hollow sections are modelled in ABAQUS Software and their performance studies are conducted with stiffness as parameter. The Hollow RC beam strengthened with MS pipe Section showed more stiffness than the MS box section and conventional beam for 1P, 2P and UD loadings making it the most economical section.

Background Localization and resection of nonvisible, nonpalpable pulmonary nodules during video-assisted thoracoscopic surgery is challenging. In this study we developed a surgical navigation puncture robot system in order to locate small pulmonary nodules before thoracoscopic surgery. Methods Four pigs were divided into group A and group B and underwent positioning puncture with the aid of the robotic system. The pigs in group A breathed freely during the experiment, whilst mechanical ventilation was used on the pigs in group B. Results Using the robotic system to locate nodules achieved good results. For group A, a total of nine simulated nodules were created and successfully localized. The mean positioning accuracy was 9.6 ± 4.9 mm (range, 3.2-17.4 mm), and the time required for system positioning was 7.1 ± 1.0 minutes (range, 5.6-8.2 minutes). For group B, a total of 23 simulated nodules were created and successfully localized. The mean positioning accuracy was 2.9 ± 1.5 mm (range, 0.7-5.9 mm), and the time required for system positioning was 7.8 ± 1.1 minutes (range, 6.3-9.7 minutes). Conclusions The new method using a surgical navigation puncture robot system to locate small pulmonary nodules is feasible and safe, and its positioning accuracy is sufficient to meet clinical requirements. In addition, results indicated that breathing had a great influence on the positioning accuracy, mainly in the longitudinal direction. Our surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting. Key points Significant findings of the study: A new method using a surgical navigation puncture robot system was developed to locate small pulmonary nodules before thoracoscopic surgery. The results indicated that this method can provide accurate localization and permit smaller and more precise resections. What this study adds A surgical navigation puncture robot system has wide future applications for accurately locating small pulmonary nodules in a clinical setting.

Landslide profile has been widely used in the dynamics analysis, characteristics illustration and parameter measurement along the longitudinal direction of landslide. However, landslide profile and landslide characteristic parameters that can be derived from landslide profile have not been formally included in landslide inventories. This paper firstly presented a newly developed algorithm for automatic generation of landslide profile, and then suggested 14 parameters that can be directly derived from landslide profile to characterize landslides. The proposed approach has been coded in a freely available R script called ALPA. A case study showed that the profiles of landslides with various scales and morphologies can be successfully generated by ALPA. A correlation analysis suggested that the 14 parameters can provide independent and informative complements to landslide characterization, which are different from the landslide area and volume. The results also implied that landslide area, which quantifies the total area affected by a landslide, is highly correlated with the product of volume and maximum drop height and the product of volume and maximum residual height, which are related to destructive power. Although limited by some complications, ALPA provides a practical tool for producing landslide profiles and landslide characteristic parameters, which are valuable complements to landslide inventory.

Recapitulating aligned cellular architectures of native tissues in vitro is important to engineer artificial tissue analogs with desired biological functions. Here a novel strategy is presented to direct three-dimensional (3D) cellular alignment by embedding cell/collagen hydrogel into the predefined electrohydrodynamically-printed microlattices. The cell/collagen hydrogel, originally filled within the printed microlattices uniformly, was found to gradually develop into densely-populated and highly-aligned bands along the longitudinal direction of the printed microlattices. The cellular alignment was highly dependent on the height, spacing and orientation of the microlattices. The presented method was applicable to multiple cell types including primary cardiomyocytes and the gaps formed between the aligned bands and the lateral walls of the microlattice facilitated the subsequent seeding and rapid alignment of other cell types which enables to engineer anisotropic multicellular tissue constructs. The engineered cardiac patches expressed mature cardiomyocyte-specific phenotypes and exhibited synchronous contractive activities. Multilayer cellular alignment with varied orientation in 3D collagen hydrogel was successfully achieved by using electrohydrodynamically-printed microlattices with layer-specific orientations. This exploration offers a promising way to engineer complex 3D tissue constructs with predefined cellular alignments. Statement of significance Fabrication of biomimetic highly-aligned complex cellular architectures has a great significance to recapitulate the unique mechanical and physiological functions of the engineered tissues (e.g., heart tissue, neuron, muscle). Here, we introduced a novel strategy to direct 3D cellular alignment by embedding cell/collagen hydrogel into the predefined electrohydrodynamically-printed microlattices without any external stimuli. The microscopical study of the dynamic alignment process of cells and collagen fibers contributed to exploring the mechanism of autonomous formation of highly-aligned cellular bands. Multilayer cellular alignment with varied orientation in 3D collagen hydrogel was successfully achieved by using the microlattices with layer-specific orientations, which showed a promising way to engineer complex 3D tissue constructs with predefined cellular alignments.

Pleated fabrics represent one of the most important 3D-fabrics. They contain the wrinkles effect in the longitudinal or cross-direction or in the diagonal direction, and are formed as folds. These folds or pleats are laid at 90° up to the ground fabric. This type of woven structures is called also folded fabrics or Plisse. Their production methods are enclosed in three methods till nowadays, which are weaving, synthetic resin equipment and sewing. In the weaving method, only wrinkles effect in the longitudinal direction could be woven. On the other hand, this effect and the others could be achieved by the different production methods which are mentioned before. The main goal of this paper is development of some mechanical devices on the weaving machine. Through which, the performances of the woven pleated fabrics could be enhanced. The development´s procedures have to secure the high quality of the woven pleated fabrics. Dimension stability, balanced structure and manufacturing economics are the desiredcharacteristics of the research. These performances are difficult to be carried out by actual traditional weaving machines. From a practical point of view, it was found that these performances couldn’t be achieved by the other production methods in spite of their additional operations after weaving. The development of the weaving machine enclosed in control of the warp tension in the distance between let-off device and the healds and also control of the movement of the take-up device. These developed operations have to be controlled by control-system program which has to be built in according to constants of the weaving machine.