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Objective: Although surgical simulation using computational fluid dynamics has advanced, little is known about the accuracy of cardiac surgical procedures after patient-specific design. We evaluated the effects of discrepancies in location for patient-specific simulation and actual implantation on hemodynamic performance of patient-specific tissue-engineered vascular grafts (TEVGs) in porcine models. Methods: Magnetic resonance angiography and 4-dimensional (4D) flow data were acquired in porcine models (n = 11) to create individualized TEVGs. Graft shapes were optimized and manufactured by electrospinning bioresorbable material onto a metal mandrel. TEVGs were implanted 1 or 3 months postimaging, and postoperative magnetic resonance angiography and 4D flow data were obtained and segmented. Displacement between intended and observed TEVG position was determined through center of mass analysis. Hemodynamic data were obtained from 4D flow analysis. Displacement and hemodynamic data were compared using linear regression. Results: Patient-specific TEVGs were displaced between 1 and 8 mm during implantation compared with their surgically simulated, intended locations. Greater offset between intended and observed position correlated with greater wall shear stress (WSS) in postoperative vasculature (P

The predominant goal of the research presented in this paper is the design of a manipulator for a conveyor of bulk materials based on the given requirements. This issue is an emerging topical one mainly for the reasons of increasing efficiency and speed, as well as the safety of maintenance of machines and equipment. Especially, another essential aspect is the reduction of the physical strain on operators during service operations on the conveyor of bulk materials. The introductory part of this paper attends to the materials used for the production of steel structures, their technological processing, as well as different types of joining of their components. The practical part was set out to ascertain the mass and position of the center of gravity of the load itself – the conveyor. From the perspective of acting, it loads the entire proposed structure, although in different operating modes.

In this paper, we represent the integral of vectors of a hyperbolic simplex by volumes of facets and unit vectors pseudo-perpendicular to them. By using it, we can define a new hyperbolic centroid of a hyperbolic simplex. [ABSTRACT FROM AUTHOR]

Copyright of Ingenius, Revista Ciencia y Tecnología is the property of Universidad Politecnica Salesiana 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.)

Background: Hyperopia is a common blurred vision phenomenon that affects postural control in gait; however, current research has focused on the alteration and correction of hyperopia's physiological characteristics, ignoring the effect of hyperopia on gait kinematic characteristics. The effect of hyperopia on the basic form of movement walking is a worthy concern. Objective: To investigate the gait kinematic characteristics of male college students with varying degrees of visual acuity (normal vision, hyperopia 150°, and hyperopia 450°), as well as to provide a theoretical foundation for the effect of visual acuity on gait and fall risk reduction. Methods: Twenty-two male college students with normal visual acuity were chosen. Their vision was tested using a standard visual acuity logarithm table at normal and with 150° and 450° concave lenses. Gait kinematic data were collected under normal vision and hyperopic conditions using the PN3 Pro advanced inertial motion capture system and Axis Studio application program. Results and conclusion: 1. The change of center of gravity in Pre-double support was smaller than normal vision; Late-single support and Late-swing was larger than normal vision; 2. The percentage of the double-leg support decreased; the percentage of the single-leg support and the Late-swing increased; 3. For the joints' range of motion, Trunk flexion and extension range of motion in Pre-single support, Late-double support and Pre-swing smaller than normal visual acuity, and Late-swing larger than normal; hip internal abduction and adduction and internal and external rotation are larger than normal vision in Late-single support; knee and ankle in abduction and adduction direction are larger than normal vision in the swing stage; hip flexion and extension, internal external rotation are larger than normal vision in the swing stage. Hyperopic interventions have an impact on the kinematic characteristics of gait in male college students, mainly in terms of altered balance, increased instability, increased difficulty in maintaining trunk stability, and increased risk of injury. [ABSTRACT FROM AUTHOR]

Sustainable development is a hot issue in global research today. As a large developing country, China has increasingly prominent conflicts between water use, the population, and the economy, so it is necessary to solve the sustainable development issues represented by water use, the population, and the economy. To explore the evolutionary process for water use, the population, and the economy in China, we calculated the evolutionary path of the center of gravity for water use, the population, and the economy in China from 1965 to 2019 by using the center of gravity model, and we calculated the decomposed contributions of the evolutionary path of the center of gravity for water use, the population, and the economy in China from 1965 to 2019, which the six major areas in China contributed to, by using the center of gravity decomposed contributions model. The results show the following: (1) As a whole, the center of gravity cumulative yearly moving distance for water use was 835.77 km, and the center of gravity moving direction as well as angle were north by east, 18.95°. The center of gravity cumulative yearly moving distance for the population was 113.40 km, and the center of gravity moving direction as well as angle were south by west, 31.50°. The center of gravity cumulative yearly moving distance for the economy was 449.83 km, and the center of gravity moving direction as well as angle were south by east, 8.63°. (2) From the decomposed value contribution rate of the evolutionary path of the center of gravity in the latitude direction for water use, the population, and the economy in China from 1965 to 2019, which the six major areas in China contributed to, Northeast China contributed the most (42.26%, 34.09%, and 39.37%, respectively). The increasing proportion of total water use consumption in Northeast China most positively affected the evolutionary path of the center of gravity for water use in China, moving northwards from 1965 to 2019, and the decreasing proportion of the total population as well as gross regional product in Northeast China most negatively affected the evolutionary path of the center of gravity for the population and economy in China, moving southwards from 1965 to 2019. [ABSTRACT FROM AUTHOR]

Purpose/Background: Various methods are available for assessment of static and dynamic postural stability. The primary purpose of this study was to investigate the relationship between dynamic postural stability as measured by the Star Excursion Balance Test (SEBT) and static postural sway assessment as measured by the TechnoBody™ Pro-Kin in female soccer players. A secondary purpose was to determine side-to-side symmetry in this cohort. Methods: A total of 18 female soccer players completed testing on the SEBT and Technobody™ Pro-Kin balance device. Outcome measures were anterior, posterior medial, and posterior lateral reaches from the SEBT and center of pressure in the x- and y-axes as well as SD of movement in the forward/backward and medial/lateral directions from the force plate on left and right legs. Bivariate correlations were determined between the 8 measures. In addition, paired Wilcoxon signed-rank tests were performed to determine similarity between limb scores. Results: All measures on both the SEBT and postural sway assessment were significantly correlated when comparing dominant with nondominant lower-extremities with the exception of SD of movement in both x- and y-axes. When correlating results of the SEBT with postural sway assessment, a significant correlation was found between the SEBT right lower-extremity posterior lateral reach (r =.567, P <.05) and summed SEBT (r =.486, P <.05) and the center of pressure in the y-axis. A significant correlation was also found on the left lower-extremity, with SD of forward/backward movement and SEBT posterior medial reach (r = −.511, P <.05). Conclusions: Dynamic postural tests and static postural tests provide different information to the overall assessment of balance in female soccer players. Relationship between variables differed based on the subject's lower-extremity dominance. [ABSTRACT FROM AUTHOR]

Probability distributions for the center of gravity are fundamental tools for track fitting. The center of gravity is a widespread algorithm for position reconstruction in tracker detectors for particle physics. Its standard use is always accompanied by an easy guess (Gaussian) for the probability distribution of the positioning errors. This incorrect assumption degrades the results of the fit. The explicit error forms evident Cauchy–Agnesi tails that render the use of variance minimizations problematic. Therefore, it is important to report probability distributions for some combinations of random variables essential for track fitting: x=ξ/(ξ+μ), y=(ξ−μ)/[2(ξ+μ)], w=ξ/μ, x=θ(x3−x1)(−x3)/(x3+x2)+θ(x1−x3)x1/(x1+x2) and x=(x1−x3)/(x1+x2+x3). The first two are partial forms of the two strip center of gravity. The fourth is the complete two strip center of gravity, and the fifth is a partial form of the three strip center of gravity. For the complexity of the forth equation, only approximate expressions of the probability are allowed. Analytical expressions are calculated assuming ξ, μ, x1, x2 and x3 independent Gaussian random variables. The analytical form of the probability for the two strip center of gravity allows one to construct an approximate proof for the lucky model of our previous paper. This proof also suggests how to complete the lucky model by its absence of a scaling constant, relevant to combine different detector types. This advanced lucky model (the super-lucky model) can be directly used in trackers composed of non-identical detectors. The construction of the super-lucky model is very simple. Simulations with this upgraded tool also show resolution improvements for a combination of two types of very different detectors, near to the resolutions of the schematic model.

Patients with hypermobile Ehlers-Danlos syndrome (hEDS) frequently suffer from poor balance and proprioception and are at an increased risk for falls. Here we present a means of assessing a variety of balance and postural conditions in a fast and non-invasive manner. The equipment required is commercially available and requires limited personnel. Patients can be repeatedly tested to determine balance and postural differences as a result of disease progression and aging, or a reversal following balance/exercise interventions.

Copyright of Command Control & Simulation / Zhihui Kongzhi yu Fangzhen is the property of Command Control & Simulation Editorial Office 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.)

Porpoising is defined as unstable coupled heave and pitch motions. In this study, seven test conditions with various longitudinal locations of the center of gravity and the moment of inertia were designed to study the porpoising phenomenon of a tunnel-type planing trimaran. After comparing the lower speed limit for porpoising, this study revealed that moving the center of gravity forward could increase the lower speed limit of porpoising, but it could also increase the amplitude of heave and pitch. Furthermore, the reduction of the moment of inertia of the planing hulls could effectively reduce the oscillation amplitude of planing trimaran porpoising and improve the longitudinal stability of planing trimarans. In this test, condition A5 had a 15% reduction in the inertia moment compared to A3, but the amplitude of the pitch oscillation in porpoising decreased by 60%. Unlike conventional trimaran towing tests, this experiment studied the effect of speed on porpoising after exceeding the lower speed limit for porpoising and found that with an increase in speed, the amplitude of porpoising first increased, then decreased, and then increased again. This study defines the speed at which the amplitude of porpoising increases for the second time as the second critical speed of porpoising. The porpoising generated by a planing trimaran after reaching the second critical speed is defined as the second porpoising. Finally, the limitations of the conventional longitudinal stability limit curve method to predict the porpoising of a planing trimaran are discussed. [ABSTRACT FROM AUTHOR]

The purpose of this research is to analyze the fundamentals of kinematic structures in the starting element of motocross (Dirt Bike). To analyze the dynamic structures of movements, such as starting acceleration, linear velocity, criteria for the optimality of starting acceleration as the main factor for successful ranking in the competition. To determine the influence of the Center of Gravity of the pilot, on the successful control of the kinematic structures of the element of starting, to achieve a rational launching technique. We used the cinematic method (cyclogram analysis) to make a biomechanical analysis of the kinematic parameters of the "start" element in motocross. We shot photographic material, which is necessary for the analytical determination of the General Center of Gravity of the racer and the sports device (motorcycle). We determined the trajectory of the CG movement and the phases of the "start" element in the accelerating linear motion. The subject of research is the change in the kinematic parameters of the movements when performing a "start" in motocross. Participants in the research are six motocross racers, height 178.7±7.47 cm, weight 79.17±9.36 kg, age 32.17±8.84 y. (M±SD), BMI of 24.7 kg/m² . We used a Go Pro HERO11 Black Cinematic 5.3K60 + 2.7K240 camera to capture the stills. Graphic processing was done with PAINT 3D program, Windows 10. For the statistical analysis of the data, we used GraphPad Prism version 3.0 software. In motocross, the simplified technical inventory leads to greater mobility and precise control of the machine in the specifics of the race track. That is why we hope to clarify some kinesiological regularities transferred to the „pilot-motorcycle“ system. Accurate and precise description of the movement and definition of its main task. The competitor's position is seated, semi-seated or semi-standing depending on the acceleration phases at the start. The palms are in a grip on the handlebars. The feet are placed on the foot pegs. The torso is bent forward. The movement is translational and follows the relief of the race track. We have identified five main phases of starting in motocross: 1) body positioning phase; 2) phase of the acceleration; 3) phase of the maximum acceleration; 4) phase of the maximum speed; 5) phase of occupying position for a corridor. For the successful performance of the competitor, an important point in the start is to avoid rolling, the loss traction and begin to slide, rear drive wheel in the starting position. The optimal range of linear acceleration at which the rear wheel will not lose traction was determined, namely from a = 2.77 m/s² to 12.96 m/s² . We also determined the rear wheel load of 166.62 kg when accelerating from a standstill. This shows that the overload is about 76 kg more than the pressure that the rear wheel takes at rest. The load data of front wheel load show values of 38.78 kg on launch acceleration, which is a reduction in ground reaction force of around 50 kg. After evaluating the kinematics of the motocross riding posture, we found that the rider's upright posture gave the deceptive impression of lowering the overall center of gravity, when in fact it was the exact opposite. In fact, the rider's semi-upright position increases the height of the Center of Gravity and gives more precise control over the handling of the dynamic rider-motorcycle system. [ABSTRACT FROM AUTHOR]

BACKGROUND: Golf courses are designed with uneven terrain. These factors are especially important when facing (slope), players need to straighten the posture of each part of the body in order to complete the swing on an inclined surface such as flat ground. Amateur players may be more likely to change the movement patterns of their shots due to uneven terrain. Therefore, it may be necessary to clarify the shot characteristics of amateur players and provide reference materials for technical improvement. OBJECTIVE: The purpose of this study was to examine the effect of slope on amateur golfers' swing kinematics by analyzing the variation of time variables, body center of gravity (COG), and shot parameters of amateur golfers' swing at different ground slopes. METHODS: Six male amateur golfers participated in the experiment. The 7-iron was used for 5 swings each at three slopes: flat ground (FG, 0 ∘), ball below foot (BBF, + 10 ∘), and foot below ball (FBB, - 10 ∘). The OptiTrack-Motion capture system was used to collect kinematic data, and the three-dimensional motion data will be transmitted to Visual3D software for subsequent data analysis such as golf swing division and body COG changes. Shot parameters (carry, swing speed, ball speed, and smash factor) were recorded for each swing using the Caddie SC300 radar monitoring device. RESULTS: The results showed that there was no difference in the overall swing time and the time required for each interval at different slopes (p > 0.05) there is no significant difference in the change of the COG of the body in the forward and backward directions (p > 0.05). The three slopes of swing speed, ball speed, carry and smash factor were not significantly different (p > 0.05). CONCLUSION: The rhythm of the amateur golfer's swing was not affected by the slope, but the slope restricts the movement of the body's COG, which may affect the weight movement, and ultimately cause the performance parameters to not reach the level of the FG. [ABSTRACT FROM AUTHOR]

Copyright of Revista Internacional de Salud Bienestar y Sociedad is the property of Common Ground Research Networks 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 Systems Engineering & Electronics is the property of Journal of Systems Engineering & Electronics 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.)

The rollover tendency of upland farm machinery needs to be carefully considered because upland crop fields are typically irregular, and accidents frequently result in injuries and even death to the operators. In this study, the rollover characteristics of an underdeveloped 12 kW automatic onion transplanter were determined theoretically and evaluated through simulation and validation tests considering the mounting position of the transplanting unit and load conditions. The center of gravity (CG) coordinates for different mass distributions, and static and dynamic rollover angles were calculated theoretically. Simulation and validation tests were conducted to assess the static rollover angle under different mounting positions of the transplanting unit and load conditions of the onion transplanter. The dynamic rollover tendency was evaluated by operating the onion transplanter on different surfaces and at different speeds. According to the physical properties and mass of the onion transplanter, the theoretical rollover angle was 34.5°, and the coordinates of the CG gradually moved back to the rear wheel axle after attaching the transplanting part and under upward riding conditions. The average simulated rollover angle was 43.9°. A turning difference of 4.5° was observed between the right and left sides, where a 3° angle difference occurred due to the load variation. During the dynamic stability test, angle variations of 2~4° and 3~6° were recorded for both high and low driving speeds in the vehicle platform and transplanting unit, respectively. The overturning angles also satisfied the ISO standard. This study provides helpful information for ensuring the safety of upland crop machinery operating under rough and sloped field conditions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Chinese Society of Animal Science is the property of Chinese Society of Animal Science 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.)

To achieve an automatic technology for over-the-shoulder (OTS) launching of air-to-air missiles, this study numerically simulated the overturning process of a slender body by using the dynamic mesh method in the ANSYS Fluent 2021 software. Motion trends and force conditions during the self-turning process were obtained for different center of gravity positions. This investigation showed that a proper center of gravity position was essential for achieving the self-turning of a slender body at high and extra-wide angles of attack. The pressure center of the slender body jumped (discontinuously changed) during the overturning process. The change in the relative position between the pressure center and the center of gravity caused the angular velocity of the slender body to first increase, then decrease and gradually stabilize. These results can be used as a reference for designing the structures of self-turning slender bodies and to realize a new technology for the OTS launching of air-to-air missiles.

Suppose your father gives you a hollow cylindrical knife as a birthday gift, and your mother buys you a bag of potatoes. When the knife is pressed into a potato and the outer excess is removed, the interior of the knife yields a cylindrical core. By pressing the knife into a potato from several strategically chosen directions, you can construct some solids of intersection such that all faces are identical or one of two distinct shapes. [ABSTRACT FROM AUTHOR]

The vehicle center of gravity estimation is the key technology to the vehicle active safety system in intelligent connected vehicles. In this study, an integrated estimation approach for center of gravity (CG) combining Huber Extended Kalman Filter and Extended Kalman Filter (HEKF-EKF) is proposed. First, HEKF algorithm is used to estimate the distance between the CG and the front axle at the current time. Then, the CG height obtained by HEKF and EKF algorithms is weighted to obtain the optimal estimate value. Finally, the results show that the algorithm's estimation convergence time is 2 s, its longitudinal position estimation error is less than 2%, and its center of gravity height estimation error is less than 3%. The longitudinal and vertical positions of the vehicle CG can be accurately estimated using this method. This method can help advance the development of active safety technology. [ABSTRACT FROM AUTHOR]

• We explore how upstream incumbents navigate sustainability transitions. • We introduce an industry value chain perspective and conduct a case study. • The case is related to value chains of lead-acid and lithium-ion batteries. • We provide insights about the upstream dilemma of how to navigate transitions. An increasing body of literature on sustainability transitions addresses the business strategies of incumbents but overlooks upstream companies. By addressing this gap, we aim to explore how upstream incumbents navigate sustainability transitions. Theoretically, we introduce an industry value chain perspective, integrating the concepts of center of gravity, patterns of strategic change and organizational adaptation. Empirically, we conduct an in-depth case study of how an upstream incumbent firm navigates the established value chain for lead-acid batteries and the emerging value chain for lithium-ion batteries used in electric vehicles. The company faces a dilemma as to whether and how to maintain a vertically integrated position in the established value chain, and how and when to expand into the emerging value chain. We argue and demonstrate that for upstream companies, navigating sustainability transitions is highly dependent on the anticipation of and adaptation to the complex changes in industry value chains. [ABSTRACT FROM AUTHOR]

Copyright of Journal de Ciencia e Ingeniería is the property of Corporacion Universitaria Autonoma del Cauca 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.)

When borax gets wet, it clumps. In this case, 76,000 pounds of previously wetted borax clumped on the inside of a rail car. The unbalanced load caused the rail car to fall on a yard worker, killing him. Tracking meteorological conditions in transit from Turkey to a port in Deleware, truck transit to a warehouse, handling at the warehouse, and rail transit to an interim transfer station was key to developing the origin and cause for the rail car derailing. There was evidence that clumping had rendered the product unusable by the end-user. However, this event occurred at the interim transfer station where the rail car product was transferred to trucks. This paper describes the process of determining how and where the borax absorbed moisture and shows physics that determined derailing was the result of an unbalanced load. This demonstrates the cause and effect of this event. [ABSTRACT FROM AUTHOR]

There is a high risk of musculoskeletal discomfort and injury due to the lack of professional guidance and training in caregiving postures. This study aimed to develop a risk assessment and visualization method by analyzing caregiving postures. Participants with (n = 8) and without (n = 10) caregiving experience were recruited to simulate patient transfer from bed to wheelchair. The Rapid Entire Body Assessment (REBA) method lacked sensitivity in distinguishing the experienced and inexperienced groups. We found that the visualization of the center of gravity (COG) trajectory could represent distinct posture differences between the two groups. Based on this finding, we considered a modified REBA method combining the COG trajectory, load-bearing time, and asymmetric load parameters, named the Caregiving-REBA (C-REBA) method. Our results demonstrated that C-REBA could effectively distinguish experienced and inexperienced caregivers, especially in caregiving task Stages 2–4. In conclusion, the present work explored adjusting to the parameters of the REBA method. The proposed C-REBA method could be easily imbedded into the Internet of Things (IoT) device to assess the caregiving posture for providing visual guidance and warning of the risk of discomfort or injury.

Poor posture (thoracic hyperkyphosis) in children is reportedly caused by changes in their living environment. A previous study (conducted 30 years ago) reported that the position of the center of pressure (COP) in a child with an upright posture was approximately 40% from the heel. The present study aimed to determine the position and characteristics of the COP while standing in children aged 6–12 years. This study enrolled 83 elementary school students. A Win-Pod (Medicapteurs) platform was used to measure the COP. The COP position was expressed as a percentage from the heel as a relative ratio with a foot length of 100%. Spinal Mouse® was used to measure thoracic kyphosis, lumbar lordosis, sacral anteversion, and trunk inclination angles in the standing position. The COP position was 30.3±8.9% from the heel. We found positive correlations between the COP position, height, and weight. Further, the COP position was significantly more anterior in 28 upper elementary grade children (35.1 ± 9.2%) than in 25 middle (29.5 ± 8.6%) and 30 lower grade children (26.5 ± 6.7%). Regarding sex differences, the COP position was significantly more anterior in 46 boys (32.3 ± 9.8%) than in 37 girls (27.9 ± 6.9%). There was a weak positive correlation between the COP position and trunk inclination angle (r=0.251, p<0.05). Thus, we found that the COP position in modern children aged 6–12 years while standing was 30.3 ± 8.9% from the heel, indicating a shift toward the heel (backward) compared to that reported in previous studies. [ABSTRACT FROM AUTHOR]

This paper addresses the modeling and the control of an autonomous bicycle robot where the reference point is the center of gravity. The controls are based on the wheel heading's angular velocity and the steering's angular velocity. They have been developed to drive the autonomous bicycle robot from a given initial state to a final state, so that the total running cost is minimized. To solve the problem, the following approach was used: after having computed the control system Hamiltonian, Pontryagin's Minimum Principle was applied to derive the feasible controls and the costate system of ordinary differential equations. The feasible controls, derived as functions of the state and costate variables, were substituted into the combined nonlinear state–costate system of ordinary differential equations and yielded a control-free, state–costate system of ordinary differential equations. Such a system was judiciously vectorized to easily enable the application of any computer program written in Matlab, Octave or Scilab. A Matlab computer program, set as the main program, was developed to call a Runge–Kutta function coded into Matlab to solve the combined control-free, state–costate system of ordinary differential equations coded into a Matlab function. After running the program, the following results were obtained: seven feasible state functions from which the feasible trajectory of the robot is derived, seven feasible costate functions, and two feasible control functions. Computational simulations were developed and provided in order to persuade the readers of the effectiveness and the reliability of the approach. [ABSTRACT FROM AUTHOR]

In order to reduce the large damage caused by train derailment, protective facilities of various shapes and conditions can be installed on railroad tracks. These protective facilities are referred to as derailment containment provisions (DCPs) and three different types are used worldwide. However, there are no clear standards for DCP design such as installation location, size, and design load, and the performance verification of DCPs installed in the actual railway field is not sufficiently performed. In this paper, the functionality of DCP type I was analyzed experimentally. A method for estimating the collision (impact) load acting on the DCP was proposed. In addition, the containment effect of DCP type I according to the change in the vehicle's center of gravity was identified through a comparative analysis of the dynamic motion such as roll, pitch, and yaw. [ABSTRACT FROM AUTHOR]

Citrus supply chains (CSC) are increasingly important in research due to high loss and waste, increasing demand, wide application for other industries, and differences in CSCs from country to country. This study proposes a new structure for CSC by introducing collection points to collect citrus from the farms in Jordan Valley and transport it to a citrus hub responsible for receiving, packaging, and transporting the citrus to distribution centers. The objective of this structure is to minimize the loss and waste and provide a new supply chain (SC) with stable infrastructure to track citrus from the initial stages and implement technologies such as the Cold SC. Therefore, it is crucial to find the optimum number of collection points, citrus hubs, and locations based on carbon footprint and transportation costs. The model introduced was solved using Open Solver Adds-ins after collecting data such as distances and coordinates using Google Maps and the altitude of those coordinates from SolarGIS. After running the model, it was found that the optimum number of collection points is 52 and the optimum number of citrus hubs is two. The results showed that the transportation costs of one hub are lower by 30%, whereas for two hubs are lower by 60% compared to the current location of the central market of fruits and vegetables (CM). The "kg CO2 e/kg citrus" values are 0.48 and 0.24 for one hub and two hubs, respectively, which showed a significant reduction compared to CM, which was 0.69 kg CO2 e/kg citrus. Therefore, installing two citrus hubs will improve the overall sustainable performance of CSC. Future research might be directed to integrate the circular economy into CSC and find possible applications for citrus loss and waste. [ABSTRACT FROM AUTHOR]

The center of gravity concept is one of contemporary military science's fundamental yet highly controversial pillars. Although, over the past decades, the center of gravity has become the modus operandi of the planning and conduct of (major) military operations in a number of armed forces, the concept remains insufficiently understood and is often poorly applied in practice. In this light, we have sought to improve its theoretical comprehension by identifying the conceptual dimensions that the most influential authors commonly highlight. Using the structural method for the concept analysis, we have identified seven entities frequently understood as the potential centers of gravity. These are: (1) fielded military, (2) leadership, (3) industry, (4) infrastructure, (5) population, (6) public opinion, and (7) ideology. [ABSTRACT FROM AUTHOR]

Purpose: We sought to compare the radiographic parameters concerning the sagittal alignment of the standing whole-body skeletons between the knee extension group and control group using the low-dose biplanar X-ray system in a young adult population without knee pain, and to investigate the associated variables for the sagittal knee angle (sagKA) among the radiographic parameters of global sagittal alignment. Materials and Methods: We reviewed whole-body standing sagittal radiographs of 124 young adults taken from December 2018 to May 2020 in a single institution. We compared the radiographic parameters concerning the lower extremity sagittal alignment and global sagittal alignment between the knee extension group and control group. The factors correlated with sagKA were evaluated using multiple linear regression analysis. Results: The sagittal vertical axis (SVA), the horizontal offset between the gravity line (GL) and the posterior edge of S1 endplate (GL-S), and the horizontal offset between the GL and the hip center (GL-H) were -11.6±21.3 mm, 5.1±23.8 mm, and -25.1±27.1 mm in the knee extension group, respectively, which were significantly smaller than those in the control group. The C7 plumb line (C7PL) and GL were deviated posterior to the sacrum and the hip center in the knee extension group, with the mean sagKA of -5.6° in young adults. Conclusion: The GL-H using GL, not the SVA using C7PL, was a significant radiographic factor associated with the sagKA. [ABSTRACT FROM AUTHOR]

To assess the changes in speed, stroke frequency, acceleration, and shoulder range of motion (ROM) associated with different wheelchair axle positions in people with chronic C7 tetraplegia. This repeated-measures study was conducted at the Chronic Spinal Cord Injury Unit, FLENI Escobar, Argentina. The speed, stroke frequency, acceleration, and shoulder ROM during wheelchair propulsion were measured in nine participants with C7 spinal cord injury (SCI) in four different axle positions (forward and up, forward and down, backward and down, backward and up). Two strokes performed at maximum speed were analyzed on a smooth level vinyl floor in a motion analysis laboratory. Data were analyzed for significant statistical differences using the Friedman test and the Wilcoxon signed rank test. Our study showed significant differences in the speed with axle position 1 (1.57 m/s) versus 2 (1.55 m/s) and position 2 (1.55 m/s) versus 4 (1.52 m/s). The shoulder ROM showed a significant difference in the sagittal plane in position 2 (59.34 degrees) versus 3 (61.64 degrees), whereas the stroke frequency and the acceleration parameters showed no statistically significant differences with the different rear axle positions. Our study showed that modifying the rear axle position can improve the propulsion speed and produce changes in the shoulder ROM in the wheelchair propulsion of individuals with C7 SCI. [ABSTRACT FROM AUTHOR]