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The characteristic subcutaneous hemorrhage along the seat belt in motor vehicle accidents is called the seat belt sign (SBS). The risk of organ injuries is especially high when abdominal SBS is located above the anterior superior iliac spine (ASIS). The purpose of this study analyzed the physical and radiographic factors of healthy volunteers sit on car seat that affect initial position of abdominal seat belt, namely "lap belt", related to the seat belt injury. This study was examined prospectively relation between physical characteristics of one hundred healthy volunteers and lap belt position sitting the car seat. Physical findings were clarified age, sex, height, body mass index (BMI), and waist circumference. Radiographical findings were measured lumber lordosis (LL), sacral slope (SS), and initial lap belt position by marking with lead tape for the center and ASIS of the lap belt installed on the driver's car seat. In the lateral X-ray image, we measured the horizontal distance (X-value) and vertical distance (Z-value) from the ASIS to the central marker. The lap belt angle was determined to measure the angle between the horizontal line and the straight line connecting the upper edges of the markers. Statistical analysis of the relationships between physical characteristics and radiological findings was performed. X-value and Z-value were positively correlated with body weight, BMI, and waist circumference, while the lap belt angle was negatively correlated with body weight, BMI, and waist circumference. The relationship between physical characteristics and the initial position of seat belt was analyzed. Since the lap belt is positioned higher than the ASIS in occupants with a high BMI, it is likely to cause seat belt injury. This analysis can help to develop safer seat belts and to enlighten car occupants. [ABSTRACT FROM AUTHOR]

With the continuous increase in the number of cars, traffic safety problems are also becoming more and more serious, whether the driver wears a seat belt to protect the driver's personal safety so that the problem can be solved in the event of a traffic accident. The author puts forward the research status of deep learning and convolutional neural network, as well as its theory and technology, and conducts in-depth analysis and research, a small target detection algorithm Deconv-SSD based on transposed convolution is proposed, driver area localization algorithm Squeeze-YOLO is based on lightweight model, and driver seat belt detection algorithm is based on semantic segmentation. Deconv-SSD achieves fast vehicle detection through depthwise separable convolution and fusion of multiresolution feature maps and then utilizes the salient features of the front windshield; through the method of lightweight feature extraction and the Squeeze-YOLO algorithm, the rapid positioning of the driver area is realized. Fast segmentation of seat belts is based on semantic segmentation algorithm and pruning technology in the positioning area, and by judging the maximum connected domain area after segmentation, the driver's seat belt detection is realized. Experiments and data analysis are carried out on the proposed algorithm. When the image resolution is consistent with the feature extraction model, the average accuracy of Deconv-SSD is compared with the original SSD algorithm in the PASCALVOC public dataset, from 77.2% to 79.6%. In the self-made seat belt detection dataset, Squeeze-YOLO can reach 73 FPS when the average accuracy is 99.96%, the semantic segmentation algorithm accelerated by pruning achieves an accuracy of 94.87% at a speed of 305 FPS, and the validity of the experiment is verified. [ABSTRACT FROM AUTHOR]

Autonomy is a ubiquitous team design feature, which is purported to relate positively to team effectiveness. However, the theoretical link between team autonomy and team effectiveness is not well understood, and previous studies have found inconsistent relations between them. We aim to resolve this incomplete understanding by examining "why" autonomy relates to team effectiveness, "what" aspects of team effectiveness are affected by team autonomy, and "when" the relations vary. To do so, we investigated task‐ and relationship‐focused team functioning as mediators, expanded the construct of team effectiveness beyond just team performance to include attitudes, and tested the moderating effects of task routineness and interdependence. Our meta‐analyses based on 415 effect sizes from 69 studies conducted on approximately 6,035 teams revealed that team autonomy positively relates to both task‐ and relationship‐focused team functioning. The results showed significant indirect effects of autonomy on both team performance and attitudes via both types of team functioning. Task routineness weakened the effect of team autonomy on task‐focused functioning and, ultimately, on team performance and attitudes, while it did not change the effect on relationship‐focused functioning. The influence of team autonomy did not vary by the level of task interdependence. Theoretical and practical implications are discussed. [ABSTRACT FROM AUTHOR]

In a front-end crash of a school bus, the existing child restraint system does not provide effective protection to the neck, although it can well protect other regions of the body, including the head and chest. In this study, we developed multi-body seat models with compartmentalization (no belt), lap belt and lap/shoulder belt. We verified the models against sled tests considering dummy motion trajectory and neck injury metrics. Next, we proposed two strategies to improve school bus seats, namely, equipping an energy-absorbing block to the seatback and adding a revolute joint between the seatback and the seat frame. We evaluated the performance of each improved strategy in terms of neck protection based on the validated models. The results showed that both improvements effectively reduced neck injury. This study can provide useful guidance for the design of new school bus restraint systems. [ABSTRACT FROM AUTHOR]

The vehicular market is undergoing a profound transformation that includes a trend toward fully automated driving. When travelling in automated systems, the main task is no longer driving. Therefore, the interior design of automated vehicles requires a renovation to adapt to new use cases. With this motivation, the use case of sleeping while travelling was chosen for this user study, in which different seat configuration conditions were evaluated. The three preselected seat positions for this research included the upright, reclined and flat seat positions. To the best of our knowledge, this study is the first to examine the comfort of different seat angles in meeting the need to sleep in a moving vehicle. Since the physical experience of the occupants with a high-fidelity seat prototype is essential to evaluate the new interior concept of the vehicle of the future, in this study, the experimental participants were asked about their perception of comfort and overall user experience while travelling by car under close-to-real test conditions. Therefore, the primary objective of this evaluation was to explore different seat configurations and find the most suitable seat position for the use case of sleeping in a car while moving. Our findings suggest that users prefer reclining and flat seats in short-/medium- and long-term use cases, respectively. [ABSTRACT FROM AUTHOR]

The CCP's political direction and politics in China will also further impact, in direct and indirect ways, research on Africa and China relations, as China seeks to develop its role as a funder of research on Africa and by Africans. Beyond inter-state and political party relations, the results of Afrobarometer's national surveys in 34 African countries in 2019/2021 found that China is second to the USA as "the preferred development model for Africans" and that 'Positive views of China's influence do not appear to affect Africans' attitudes toward democracy'. One way FOCAC presents a misleading impression of a continental-like country and a continent meeting in inter-state terms, notwithstanding the different parts of the Chinese state actively involved, is by formally downplaying an otherwise very much present reality, namely the centrality of the CCP in China's African ties. It saw the Chinese government, 53 African countries and the African Union (AU) Commission meet under the theme 'Deepen China-Africa Partnership and Promote Sustainable Development to Build a China-Africa Community with a Shared Future in the New Era'. [Extracted from the article]

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Abstract: Driver fatigue is an important contributor to road accidents. This paper reports a study that evaluated driver fatigue using multimodal fatigue measures, i.e., surface electromyography (sEMG), electroencephalography (EEG), seat interface pressure, blood pressure, heart rate and oxygen saturation level. Twenty male participants volunteered in this study by performing 60 min of driving on a static simulator. Results from sEMG showed significant physical fatigue (ρ < 0.05) in back and shoulder muscle groups. EEG showed significant (ρ < 0.05) increase of alpha and theta activities and a significant decrease of beta activity during monotonous driving. Results also showed significant change in bilateral pressure distribution on thigh and buttocks region during the study. These findings demonstrate the use of multimodal measures to assess early onset of fatigue. This will help us understand the influence of physical and mental fatigue on driver during monotonous driving. [Copyright &y& Elsevier]

Occupants of automobiles experience discomfort after long drives, irrespective of how well designed a seat might be. Previous studies of discomfort during driving have focused either on the seat shape and materials ("static" properties), long-term discomfort ("fatigue" properties), or dynamics ("vibration" properties). These factors have previously not been considered together. This paper reports three studies with objectives to define and test a model for describing long- term discomfort from vibration. Study 1 was an independent measures laboratory trial using an automobile seat, which lasted 80 minutes; Study 2 was a repeated measures laboratory trial using a rail passenger seat, which lasted 60 minutes; Study 3 was a repeated measures field trial in a people carrier automobile, which involved 70 minutes of travelling. The findings showed that discomfort accrues with time but that more discomfort is experienced when subjects are also exposed to whole-body vibration. Exposure to whole-body vibration accelerates development of discomfort. The relationship between the reported discomfort, the vibration magnitude, and the exposure time can be described using a multifactorial linear model. It is concluded that ignoring parts of the multi-factorial model (i.e., static, dynamic, or temporal factors) will compromise understanding of discomfort in context. [ABSTRACT FROM AUTHOR]

In order to improve operating noise performance of a seat adjuster mechanism, benchmarking measurements were conducted in different cars for six and eight types of seat adjustment operation. The six types of operation include: seat moving up, seat moving down, seat front end up, seat front end down, seat rear end up and seat rear end down. The eight types of operation include: seat moving forward, seat moving backward, seat moving up, seat moving down, seat front end up, seat front end down, seat rear end up and seat rear end down. The noise and vibration levels, sound quality and root causes of the noise problem have been analysed and discussed in this paper. The noise characteristics have been identified, and the psychoacoustic parameters have been used to quantify sound quality of the seat adjuster. The objective assessment results have been found to match well with subjective evaluation results. [ABSTRACT FROM AUTHOR]

• ANC for multiple broadband noises is developed and verified using airplane seat. • The components of the ANC system are small enough to mount into the cushion. • Without wearing anything, ANC automatically locates quiet zones to cover passenger's ears. • The passenger is free to swing or move his head, 8–12 dBA noise reduction is around user's ears. This work describes a multi-functional active noise control (ANC) system installation in an airplane seat. Most researchers in the field have focused on systems that cancel narrowband noise on headrests owing to the causality constraint of ANC system. Therefore, ANC systems in seats have limited performance. In this paper, an ANC system is designed for an airplane seat and the electronic delay of the ANC system is reduced to meet the causality requirement of a feedforward ANC system. An infrared sensor is used to detect the head of the occupant of the seat, so the ANC system can automatically cause the quiet zone to surround the ears of users with various sitting postures. Multiple noise sources and the automatic activation function of the ANC system are discussed. Experimental results show that the proposed ANC system for an airplane seat effectively reduces recorded airplane noise without the need for earplugs or an ANC headset. [ABSTRACT FROM AUTHOR]

Taxicab security cameras are widely used to deter crimes against taxicab drivers in two-row-seating taxicabs. Some of these cameras have difficulty for use in three-row-seating taxicabs due to increased distance between the camera and the third-row seats. This project tested five sample taxicab security cameras with different image-sensor pixel counts to determine their utility for three-row-seating taxicabs. The cameras videotaped a normalized camera resolution test chart mounted in the third-row seat of a simulated three-row-seating taxicab in both daylight and dark (with infrared radiation) conditions. The resolution of each camera was measured and compared with the resolution threshold for customer facial identification. A dome-mounted camera with a standard-definition image-sensor is suggested as an effective camera in sustaining high camera resolution with small data file size for facial identification in the third-row seats. The image-sensors with at least 1280 × 720 pixels are suggested for windshield-mounted cameras in three-row-seating taxicabs for facial identification. [ABSTRACT FROM AUTHOR]

Since welding technology is currently used to assemble the frame of driver's seats, it is important to develop laser welding technology for steel and aluminium. For this reason, the purpose of the present work was to examine the structure and selected properties of aluminium-steel joints using the example of an EN AW-6060 aluminium alloy and DC04 low-alloy steel welded in laser technology. Overlapping joints were made, weld type -following the hole laser welding method -laser beam (LB) using a high power disk laser (TRUMPF TruDisk3302), in which the active medium is a yttrium-aluminium crystal (YAG). Metallographic microstructure investigations were carried out using a light microscope from Carl Zeiss - Observer Z1m, and the weld microstructures were investigated using an SEM Supra 35 microscope, also from Carl Zeiss. The chemical composition analysis in micro-areas was carried out using an X-ray energy dispersion spectrometer from EDAX, which was a part of the SEM Supra 35. The hardness of the substrate material and the welded area was measured following the Vickers method using an FM-ARS 9000 micro hardness tester from Tokyo, Japan. It was found that there is a potential for commercial use of laser welding to make a low-carbon steel-aluminium alloy joint. During the formation of the weld in its microstructure, intermetallic compounds of the FexAly type were created, which significantly reduced the mechanical and plastic properties of the joint. The hardness of the weld created wasabout seven times higher than that of DC04 carbon steel. The choice of laser welding parameters (primarily, laser power and beam speed) significantly impacted the weld structure and properties. [ABSTRACT FROM AUTHOR]

Abstract: This paper designs and fabricates a vibration isolation model for improving vibration isolation effectiveness of the vehicle seat under low excitation frequencies. The feature of the proposed system is to use two symmetric negative stiffness structures (NSS) in parallel to a positive stiffness structure. Here, theoretical analysis of the proposed system is clearly presented. Then, the design procedure is derived so that the resonance peak of frequency–response curve drifts to the left, the load support capacity of the system is maintained, the total size of the system is reduced for easy practical application and especially, the bending of the frequency–response curve is minimized. Next the dynamic equation of the proposed system is set up. Then, the harmonic balance (HB) method is employed to seek the characteristic of the motion transmissibility of the proposed system at the steady state for each of the excitation frequency. From this characteristic, the curves of the motion transmission are predicted according to the various values of the configurative parameters of the system. Then, the time responses to the sinusoidal, multi frequency and random excitations are also investigated by simulation and experiment. In addition, the isolation performance comparison between the system with NSS and system without NSS is realized. The simulation results reveal that the proposed system has larger frequency region of isolation than that of the system without NSS. The experimental results confirm also that with a random excitation mainly spreading from 0.1 to 10Hz, the isolation performance of the system with NSS is greatly improved, where the RMS values of the mass displacement may be reduced to 67.2%, whereas the isolation performance of the system without NSS is bad. Besides, the stability of the steady-state response is also studied. Finally, some conclusions are given. [Copyright &y& Elsevier]

Abstract: In this paper, we propose a new schedule-based equilibrium transit assignment model that differentiates the discomfort level experienced by sitting and standing passengers. The notion of seat allocation has not been considered explicitly and analytically in previous schedule-based frameworks. The model assumes that passengers use strategies when traveling from their origin to their destination. When loading a vehicle, standing on-board passengers continuing to the next station have priority to get available seats and waiting passengers are loaded on a First-Come-First-Serve (FCFS) principle. The stimulus of a standing passenger to sit increases with his/her remaining journey length and time already spent on-board. When a vehicle is full, passengers unable to board must wait for the next vehicle to arrive. The equilibrium conditions can be stated as a variational inequality involving a vector-valued function of expected strategy costs. To find a solution, we adopt the method of successive averages (MSA) that generates strategies during each iteration by solving a dynamic program. Numerical results are also reported to show the effects of our model on the travel strategies and departure time choices of passengers. [Copyright &y& Elsevier]

Abstract: This paper proposes a frequency-based assignment model that considers travellers probability of finding a seat in their perception of route cost and hence also their route choice. The model introduces a “fail-to-sit” probability at boarding points with travel costs based on the likelihood of travelling seated or standing. Priority rules are considered; in particular it is assumed that standing on-board passengers will occupy any available seats of alighting passengers before newly boarding passengers can fill any remaining seats. At the boarding point passengers are assumed to mingle, meaning that FIFO is not observed, as is the case for many crowded bus and metro stops, particularly in European countries. The route choice considers the common lines problem and an user equilibrium solution is sought through a Markov type network loading process and the method of successive averages. The model is first illustrated with a small example network before being applied to the inner zone of London’s underground network. The effect of different values passengers might attach to finding a seat are illustrated. Applications of the model for transit planning as well as for information provision at the journey planner stage are discussed. [ABSTRACT FROM AUTHOR]

Objective: This study aims to investigate the effects of seating posture and seat cushion properties on submarining risk for rear seated children. Methods: An instrumented 6-year-old Hybrid III dummy restrained by an inertial-reel 3-point seat belt was subjected to simulated frontal impacts (Δv = 28.8 km/h, peak acceleration = 16 g). Dummy motion was captured using high-speed digital video. Head acceleration, neck loads, chest deflection, pelvic rotation, and femur displacement were used to assess submarining. Factors investigated included pre-impact seating posture, seat cushion length, stiffness of the seat cushion foam, and the inclination of the seat cushion. Results: The most severe submarining was observed when the dummy was seated in a slouched posture where pelvic rotation was over 3 times greater than in the upright seating posture. Though the standard seat cushion with the dummy seated in the upright posture recorded the lowest values of pelvic rotation and femur displacement, it is unlikely that a child will sit in such a posture. The shortened seat cushion increased femur displacement by 19 percent compared to the standard test seat, but it offers good pre-impact belt position. Submarining occurred in cases where the front edge of the seat collapsed during interactions with the dummy's buttocks. Conclusions: These data suggest that shortening the rear seat cushion alone will not necessarily prevent submarining, but this does allow improved seated posture of the occupant, thus reducing submarining risk. This study has also shown that the collapse of the front edge of the seat cushion is a critical factor in submarining risk. [ABSTRACT FROM AUTHOR]

Abstract: This paper applies price differentiation of time segment, service class, and advance purchase to modeling cabin choice behavior. The proposed model was constructed with combining revealed-preference and stated-preference and validated by the case of reserved and unreserved-seat cabins in Taiwan high-speed rail. Furthermore, this study also investigates the effect of seat uncertainty in order to estimate its monetary value. The empirical results reveal that time discount and seat available definitely act as important roles on cabin choice behavior as well as fare level. Scenario analysis suggests cabin allocation should vary with time segment and trip characteristics. [ABSTRACT FROM AUTHOR]

Abstract: Consumer expectations for automobile seat comfort continue to rise. With this said, it is evident that the current automobile seat comfort development process, which is only sporadically successful, needs to change. In this context, there has been growing recognition of the need for establishing theoretical and methodological automobile seat comfort. On the other hand, seat producer need to know the costumer’s required comfort to produce based on their interests. The current research methodologies apply qualitative approaches due to anthropometric specifications. The most significant weakness of these approaches is the inexact extracted inferences. Despite the qualitative nature of the consumer’s preferences there are some methods to transform the qualitative parameters into numerical value which could help seat producer to improve or enhance their products. Nonetheless this approach would help the automobile manufacturer to provide their seats from the best producer regarding to the consumers idea. In this paper, a heuristic multi criteria decision making technique is applied to make consumers preferences in the numeric value. This Technique is combination of Analytical Hierarchy Procedure (AHP), Entropy method, and Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS). A case study is conducted to illustrate the applicability and the effectiveness of the proposed heuristic approach. [ABSTRACT FROM AUTHOR]

Abstract: Berth scheduling aims to optimally schedule vessels to berthing areas along a quay and is a complex optimization problem. In this paper we propose a lamda-optimal based heuristic as a resolution approach for the discrete space berth scheduling problem. The proposed heuristic can also be applied to validate optimality, in the case where other (meta)heuristics are applied as resolution approaches. A second internal Genetic Algorithms based heuristic is also proposed to reduce the computational time required for medium to large scale instances. Numerical experiments performed show that the proposed heuristic is adequate to produce near-optimal results within acceptable computational times. [Copyright &y& Elsevier]

Lower neck shear force remains a viable candidate for a low-velocity automotive rear-impact injury criterion. Data were previously reported to demonstrate high correlations between the magnitude of lower neck shear force and lower cervical spine facet joint motions. The present study determined the ability of lower neck shear force to predict soft-tissue injury risk in simulated automotive rear impacts. Rear-impact tests were conducted at two velocities and with two seatback orientations using a Hybrid III anthropomorphic test device (ATD) and stock automobile seats from 2007 model year vehicles. Higher velocities and more vertical seatback orientations were associated with higher injury risk based on computational modeling simulations performed in this study. Six cervical spine injury criteria including NIC, Nij, Nkm, LNL, and lower neck shear force and bending moment, increased with impact velocity. NIC, Nij, and shear force were most sensitive to changes in impact velocity. Four metrics, including Nkm, LNL, and lower neck shear force and bending moment, increased for tests with more vertical seatback orientations. Shear force was most sensitive to changes in seatback orientation. Peak values for shear force, NIC, and Nij occurred approximately at the time of head restraint contact for all four test conditions. Therefore, of the six investigated metrics, lower neck shear force was the only metric to demonstrate consistency with regard to injury risk and timing of peak magnitudes. These results demonstrate the ability of lower neck shear force to predict injury risk during low velocity automotive rear impacts and warrant continued investigation into the sensitivity and applicability of this metric for other rear-impact conditions. [ABSTRACT FROM AUTHOR]

This paper presents a study of the results obtained by a numerical simulation of a vehicle model while driving over a road bump. In contrast to the classic, so-called full-vehicle model consisting of 7 degrees of freedom (DOF), an additional degree of freedom, connected with the driver's seat, is taken into account. By means of a numerical solution of the 8-degreeof- freedom model the natural frequencies as well as the vibration responses of the vehicle wheels, chassis (pitch, roll, and heave), and driver's seat are calculated in the time and frequency domain. The excitation effects of the road bump are taken into account in two different ways, i.e. in the form of short-duration excitation, resulting in the excitation of natural frequencies of the masses in the vibration system, and in the form of periodic excitation, resulting from passing over the road bump with the front wheels and after a time delay with the rear wheels. In addition, the influence of vibration parameters, such as riding speed, driver's mass including the seat, and stiffness and damping of the driver's seat, on the vibrations of the driver's seat are analyzed. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the behavior of human body under the influence of vibration is of great importance for the optimal motor vehicle system design. Therefore, great efforts are being done in order to discover as many information about the influence of vibration on human body as possible. So far the references show that the major scientific attention has been paid to vertical vibration, although intensive research has been performed lately on the other sorts of excitation. In this paper, the results of the investigation of behavior of human body, in seated position, under the influence of random fore and aft vibration are shown. The investigation is performed by the use of an electro-hydraulic simulator, on a group of 30 healthy male occupants. Experiments are performed in order to give results to improve human body modeling in driving conditions. Excitation amplitudes (1.75 and 2.25m/s2 rms) and seat backrest conditions (with and without inclination) were varied. Data results are analyzed by partial coherence and transfer functions. Analyses have been performed and results are given in detail. The results obtained have shown that the human body under the influence of random excitations behaves as a non-linear system and its response depends on spatial position. Obtained results give necessary data to define structure and parameters of human biodynamic model with respect to different excitation and seat backrest position. [Copyright &y& Elsevier]

This paper presents the validation of a 50th-percentile male multi-body human model specifically developed for rear-impact simulation. The aim is to develop a biofidelic model with the simplest architecture that can simulate the interaction of the human body with the seat during rear impact. The model was validated using the head-and-neck and torso responses of seven volunteers from the Japanese Automobile Research Institute sled tests, which were performed at an impact speed of 8 km/h with a rigid seat and without head restraint and seat belt. The results indicate that the human-body model can effectively mimic the rear-impact response of a 50th-percentile male with a good level of accuracy and has the potential to predict whiplash injury. [ABSTRACT FROM AUTHOR]

The paper presents the rescue systems of submarines used worldwide. The idea of rescue seats was explained and described. The seat's load caused by the pressure of hydrostatic pressure, the thrust of the rescue vehicle, and the sea current was defined in accordance with the requirements of STANAG 1297. According to the standard, an analysis of the stress state of a Kobben-class submarine rescue seat loaded with the pressure of an emergency vehicle was carried out. The sea current and hydrostatic pressure at a depth of 700 m were taken into account. Non-linearities related to the description of the material and large deformations were used. Johnson-Cook characteristics for HY-80 steel are described. The stress state results in a Kobben-class submarine rescue seat obtained based on FEM simulations for a submersion depth of 700 m are presented. The results are shown in two variants. Variant I - following the standard, Variant II – author's proposal. Then differences were demonstrated, and additional recommendations were proposed. • To increase the safety of submarines sailing, the strength of their rescue seats should be analyzed. • The current analysis contained in the standards may be inappropriate and generate higher stress results. • It is necessary to develop sea rescue in the field of rescuing submarine crews. [ABSTRACT FROM AUTHOR]

A novel polypropylene glycol (designated PPG) which contains an extremely smaller amount of by-products (monols) was developed to improve the riding comfort of an automotive seating foams, The current trend in the automotive seating industry is moving to low resilience molded foam due to the structure change from "full foam" to "foam and high tension spring combination," new automotive seating foams were desired to have low resilience with keeping the low transmissibility at 6 Hz. Riding comfort mainly consists of three factors such as static property, dynamic property and durability. Each issue was solved by means of increasing the polymer molecular weight and the crosslinking density in the polymer matrix. Furthermore, it was also cleared that the transmissibility at resonance frequency of the foam can lower by means of the adjustment of closed cell ratio in the foam. In this paper, we describe the foam properties (static property, dynamic property, durability) of TDI/MDI based molded foams and make clear the mechanism of the Riding comfort of automotive seating foams. [ABSTRACT FROM AUTHOR]

Abstract: Consumer expectations for automobile seat comfort continue to rise. With this said, it is evident that the current automobile seat comfort development process, which is only sporadically successful, needs to change. In this context, there has been growing recognition of the need for automobile seat comfort researchers to establish a theoretical and methodological foundation. Only in this way can automobile seat comfort achieve recognition as a true scientific discipline and enable its further development. The present contribution hopes to stimulate and lead researchers to focus on a framework through which this recognition and development can take place. This paper describes the current automobile seat comfort development process and details the associated limitations. The limitations were the catalysts for the creation of a systematized framework intended to direct the investigative process associated with seat comfort research. The framework is expected to produce theories and methods that can explain, guide, and further legitimize the discipline of automobile seat comfort. [Copyright &y& Elsevier]

In this paper, we develop a quality improvement model based on the structure of classical economic production quantity (EPQ) model. The asymmetrical truncated loss function is used to evaluate the cost of poor quality in a production system. A practical quality improvement case which follows the 6-sigma DMAIC method in a car seat assembly line is discussed to verify the proposed model. Our model provides a fundamental structure for studying the cost of quality improvement in a production system. Based on this model, the management can evaluate the affect of quality investment to generate significant financial return in their production line. [ABSTRACT FROM AUTHOR]

This paper presents robust control performances of a semi-active electro-rheological (ER) seat suspension incorporating vibration model of human-body. A cylindrical type of ER seat damper is manufactured for a commercial vehicle seat suspension system and its field-dependent damping force is experimentally evaluated. A human-body model is then derived and integrated with the governing equations of the ER seat suspension system. The integrated seat-driver model featured by a high order degree-of-freedom (DOF) is reduced through a balanced model reduction to design robust controller. By imposing semi-active actuating conditions, a sliding mode controller which is very robust to external disturbances and parameter uncertainties is synthesized and experimentally realized with the state observer. In the experimental configuration, a driver directly sits on the controlled seat. Control results for ride quality considering response of each human body segment are evaluated in both time and frequency domains. In addition, a comparison of the proposed semi-active ER seat suspension to a conventional passive seat suspension system is undertaken. [ABSTRACT FROM AUTHOR]