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Polyester is currently the main material used for the manufacture of safety belts used in car transport for the protection of passengers and the driver. The seat belt is the main passive safety element used in vehicle engineering. In this work, the behavior of two safety belts, one with three-point fastening and the other with four-point fastening, which equip the seat of a racing car used in Formula Student for use in a frontal impact with a vertical wall. A model with finite elements is used to describe the entire car–driver shock-absorber assembly. The von Mises stresses calculated for both cases under consideration are below the tensile strength. The tensions arising in the belt and the accelerations required at various points of the driver's body are determined by both the properties of the utilized polyester and the chosen construction variant. The obtained results justify the use of the three-point and four-point belt in the cases of both common and race cars. [ABSTRACT FROM AUTHOR]

Predicting what drivers will do as vehicle control is handed over to them from automation is a relatively new challenge for the motor vehicle industry. Operator Event Sequence Diagrams (OESDs) offer a way of modeling the interactions between the driver and vehicle automation in the handover of control. In this paper, two studies are presented in which a range of handover strategies are tested. The anticipated driver strategies were modeled using OESDs to serve as predictions of driver behavior. Drivers were then observed in two separate studies: (1) using a Lower‐Fidelity (vehicle seat and controls) simulator and (2) using a Higher‐Fidelity (whole vehicle) simulator. Driver behavior during a takeover task was categorized according to the signal detection paradigm into hits, misses, false alarms, and correct rejections. The results showed that for all strategies in both sets of studies, the median criterion for validity was exceeded (φ > 0.8), suggesting that OESDs made good predictions of driver behavior during the handover of the vehicle from automation to manual control. [ABSTRACT FROM AUTHOR]

A lot of daily activities are conducted in a sedentary posture. This includes a thermal interaction between the human and the seat that has implications on thermal perception and comfort. These interactions are investigated by simulating heat and mass transfer, thus, reducing a need for costly and time demanding subject studies. However, it is not clear, from the available literature, what portion of the body surface area is actually affected by the seat with respect to human anthropometry. The aim of this study was to develop a predicting function of the seat contact area based on anthropometric parameters. The results showed strong linear correlation between the contact area obtained by printing a body silhouette on paper placed at the seat and body weight, height, body surface area, and body mass index. The body surface area and the body weight were identified as the best predictors for the contact area. [ABSTRACT FROM AUTHOR]

The tyre-suspension-seat dynamic system, driveline and engine vibrations are generally considered in the vibrational field as the main factors that influence the particular feeling of comfort perceived by passengers on a vehicle. Hence, the development of several criteria and models for the optimal estimation of the design parameters of such systems. Among these parameters, the most detrimental impacting on the passenger comfort are undoubtedly acceleration and its variation. The two types of suspension systems (conventional passive suspension system and active suspension system) differ as the first foresees the spring-damper characteristics to be adjusted so that only one of several conflicting objectives (such as passenger comfort, road holding, and suspension deflection) is followed. In active suspension systems, instead, these objectives are balanced by the designer in a more efficient manner thanks to the feedback-controller actuator assembly. However, this approach presents some limitations linked to the extremely wide spectrum of magnitude and frequency of external forces that the tyre-suspension-seat system has to efficiently control and mitigate. It remains that in the existing optimisation models and systems time exposure limits established by unification agencies and road authorities are not generally considered. This paper illustrates the development of an active tyre-suspension-seat system control for passenger cars, using both a non-linear multibody model and Genetic Algorithm (GA) controls. A benefit of the proposed active tyre-suspension-seat system control is also to consider various time exposure limits and an active damping element. The main innovative element introduced by this work consists in having coupled an active control to passive mechanical parameters in order to minimize the seat acceleration. The 3 DoF multibody model, applied to a quarter body for symmetry reasons, treated road roughness as an input variable in the GA control so as to determine the vertical component of acceleration. The numerical and experimental applications of the proposed model to a specific case study allowed to validate the effectiveness of the active system towards the vibrations transmitted to the passenger. [ABSTRACT FROM AUTHOR]

Purpose – The term luxury and sustainability, within the fashion and textile industries are seldom seen as natural bedfellows. Recently however, the perception of luxury has begun to include a definition left behind in the twentieth century; beautifully hand crafted artefacts valued for the time, skill and design invested in them. It is possible though, for the concept of luxury textiles to embrace this definition and that of the sustainable credentials of a “Cradle to Cradle” (McDonough and Braungart, 2002) mindset (that of a life beyond original creation) and be fashionable. The paper aims to discuss these issues. Design/methodology/approach – Utilising a variety of methodologies including case studies, reflective practice and a practice-based approach; this paper examines the use of pre-consumer waste in the creation of new luxury textiles. Several projects are cited, offering examples of collaboration between textile mills and designers in the creation of new fabrics made from luxury by-products. This luxury waste is routinely shredded for automobile seat filling or landfill, however current sustainable thinking encourages a more creative solution to this circumstance. Designers have a crucial role to play in converting an unwanted by-product to one that is highly desirable. Findings – Traditional values of what constitutes a luxury item include the concept of time invested in making a unique handmade artefact. More recently, this premise has been overlooked in favour of branded goods. The slow fashion movement advocates the inherent value of craftsmanship coupled with the ethical use of sustainable and or local materials and processes. The traditional techniques of felting, weave and stitch are utilised to create beautiful, original textiles from discarded waste. By collaborating with local mills, designers provide solutions to something that could be perceived as a problem. Originality/value – The embedded narrative within these layered textiles provides an original quality and added value, building on their Scottish heritage. The resulting textiles reflect their provenance; the landscape they come from and the people who created them. As a result of purchase, the story continues with the new custodian, adding to the ongoing history of the textile. The design work and collaboration that this paper outlines embodies a transferable model for sustainable upcycled luxury textiles. [ABSTRACT FROM AUTHOR]

This paper explores the impact of the decision by the National Union of Public Employees (NUPE) in 1975 to revise its constitution to include elected reserved seats for women on its executive and other bodies. The analysis is situated within the context of women's employment and trade-union representation in the UK at the time. Reserved seats for women were part of a wider restructuring of NUPE intended to extend democracy, incorporate the emergent system of shop stewards formally into its structure and government, provide for more effective representation and mobilization of different sections of members, and increase the accountability of full-time officials to lay members and their representatives. The initiative was successful; and although women's participation in NUPE did increase, this was uneven. This was not entirely unexpected given the limited change initiated in just one haltingly democratizing trade union and the wider social and economic forces that constrain women. [ABSTRACT FROM AUTHOR]

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This paper presents the replication of accelerations in a vehicle excited from single obstacle crossings. The accelerations should be replicated at multiple comfort-relevant excitation points in a comfort-simulator. For the vertical accelerations at the seat rails and the foot rests, research on the positions and the number of shakers is conducted. The implementation of an electrodynamic shaker for each controlled measurement point turns out to be mandatory. By positioning them at the left and right seat rails, errors can be minimized due to similarities in the transmission behavior. The longitudinal excitations of the seat back by means of shakers are performed very precisely. The direct coupling by a construction on the headrest allows fast exchange of the vehicle seats. The combination of all acceleration replications simultaneously can be performed satisfactorily comparing them with in-vehicle field measurements. The noise-based excitation signal for system identification turns out to be a significant parameter. [ABSTRACT FROM AUTHOR]

Purpose – In the event of a crash involving a car, its seats, together with their backrests and head supports, ensure the safety of the passengers. The filling material used for such a car seat is normally made of polyurethane foam. To simulate the behaviour of the seat assembly during a crash, the material characteristics of the seat-filling foam should be appropriately modelled. The purpose of this paper is to present a method, with which the proper parameter values of the selected material model for the seat-filling foam can be easily determined. Design/methodology/approach – In the study, an experiment with the specimen from seat-filling foam was carried out. The results from this experiment were the basis for the determination of the parameter values of the low-density-foam material model, which is often used in crash-test simulations. Two different numerical optimisation algorithms – a genetic algorithm and a gradient-descent algorithm – were coupled with LS-DYNA explicit simulations to identify the material parameters. Findings – The paper provides comparison of two optimisation algorithms and discusses the engineering applicability of the results. Originality/value – This paper presents an approach for the identification of the missing parameter values of the highly non-linear material model, if these cannot be easily determined directly from experimental data. [ABSTRACT FROM AUTHOR]

This article examines the implications of the land and agrarian reforms on 'aliens' and its multiplying effects on citizenship and their rights in Zimbabwe. It also interrogates the contested nature of citizenship in relation to land, agriculture and the rights of aliens. This is premised on a background where a frosty relationship has existed between aliens and the government, making them victims of the country's land reform programme. Settler colonialism is shown as having partly contributed to contemporary challenges and despite its demise, it continues to influence land and agrarian disputes between the government, indigenous Zimbabweans and aliens. It is against this background that this article interrogates and tells a unique story of inclusion and exclusion in rural Zimbabwe. The country's land reform programme is shown as having had deep seated socio-cultural, political and economic implications some which are now only becoming evident now. The paper uses strong field based empirical evidence, adopts an interpretive life history research approach and uses the conceptual lenses of T.H. Marshall's distinction of social citizenship (civil political and economic) to show how land reform has reconfigured rural social and economic relations. The article shows that in post land reform Zimbabwe, citizenship remains a contested issue and socially, economically and politically aliens are at a disadvantage and are failing to enjoy the rights and privileges which are due to them as enshrined in the country's laws. The article concludes that despite the politics of inclusion and exclusion in rural Zimbabwe, aliens continue to positively contribute to socio-economic and political processes in the resettlement areas. [ABSTRACT FROM AUTHOR]

Neck injuries caused by low-speed rear-end collisions are a worldwide problem. The reasonable design of car seat can effectively prevent or reduce the passenger neck injuries. In this paper, the finite element analysis (FEA) and whiplash test are combined to optimize the seat structure parameters to enhance the safety. The whiplash test results of the existing car seats according to C-NCAP (2015) were matched with FEA, and the optimization scheme was developed by computer simulation. For the improvement of seat safety, the optimizations are applied to determine backrest stiffness, backrest rotational stiffness, headrest rotational stiffness and headrest stiffness. The retest results of optimized seat show that its safety performance is greatly improved. Furthermore, it shows that the combination of finite element analysis and whiplash test can optimize seat structure to improve safety performance. [ABSTRACT FROM AUTHOR]

To achieve the secondary production in multistage fracturing wells of tight oil, milling tools are usually used to remove the multistage fracturing ball seats to achieve production with a large diameter in later. In this paper, first of all, the working mechanism of milling tools for multistage fracturing ball seats was studied and a mechanical analysis model of single abrasive grain was established. Then, an experimental system for milling tools was developed, and the experimental tests of the flat, the blade, and the slope milling tool were conducted in order. Besides, the morphology of chips and the surface morphology of the workpiece after the experiment were analyzed. Also, the working performance of milling tools was evaluated from the perspectives of working safety, working efficiency, and wear resistance of the milling tool. The results show that the torque of the milling tool increases nonlinearly with the increase in the cutting depth of the abrasive grain and increases linearly with the increase in the cutting width. Also, the chips are irregular particles and the size is mainly from 10 to 50 μm. So, the chips should be pumped up with a small pump pressure and a large displacement. Besides this, the cutting depths of the abrasive grains are from 216.20 to 635.47 μm and the bottom surface of the milling tool should be eccentric to avoid the zero point of cutting speed. Furthermore, the torque of the slope milling tool is 23.8% larger than that of the flat milling tool, which is also 30.4% smaller than that of the blade milling tool. Compared with the flat milling tool, the working efficiency of the blade milling tool improves by 79.9% and the slope milling tool improves by 111.1%. Also, the wear resistance of the blade milling tool decreases by 102.7%, while the slope milling tool declines by 32.6% when compared with the flat milling tool. Therefore, the slope milling tool has the characteristics of moderate torque, stable working conditions, the highest working efficiency, and fine wear resistance, which is preferably used to mill multistage fracturing ball seats. This study provides a theoretical basis and guidance for milling multistage fracturing ball seats on-site and realizing production with a large diameter in later stages of multistage fracturing wells. [ABSTRACT FROM AUTHOR]

The paper deals with the parameter sensitivity analysis of a passenger/seat model that can be used for ride comfort assessments. The final aim is to produce a comprehensive framework for enabling vehicle seat designers to develop comfortable (and healthy) seats, especially for those people who spend their lives while working on vehicles. In this paper a seated passenger proprietary model has been proposed and validated either by comparing it with a mathematical model derived by means of commercial software, either by experimental activities. On the basis of the validated model a sensitivity analysis has been performed, aiming to identify the key parameters affecting the ride comfort. A total of 47 parameters were accounted for. Many parameters seem relevant to describe the ride comfort of a seated road vehicle passenger. The most important conclusion of the research is that the parameters referring to posture have proved to influence ride comfort to a great extent. Other relevant but less important parameters are: the stiffness and damping of the seat, the geometry of the seat, the size and inertia properties of the body segments, and the stiffness and damping of the different parts of the human body. Different running conditions have been considered, i.e. vehicle passing over cleats or running on a randomly profiled road. Different running conditions influence differently the ride comfort, so care has to be used when performing either experimental or numerical simulations. [ABSTRACT FROM AUTHOR]

Various vibration isolators using negative stiffness elements have been proposed in order to improve ride comfort of passengers in vehicles. In this paper, five different ones are compared. Four of them have been already propped, while the fifth one is novel, based on the KDamping concept, which has proven efficient in other applications. After optimising each one with respect to static and dynamic factors of ride comfort, three types of analysis are performed. In the first type, the models are simulated for the optimum solutions, for two more excitations which correspond to the response of the vehicle's body while driving over road profiles of Class B and C. In the second type, the models are simulated for different seated passengers. While in the third type, based on the Pareto theory, three solutions are finally selected for each model, and their transmissibility from seat to head (STHT) is compared. The main conclusion is that the isolator using the KDamping concept has proven its adaptability and universality for different excitations corresponding to different road classes and for different seated passengers, minimising the resonance frequency around 0.56 Hz and providing the most compact and comfortable optimum design solutions among all the other models. [ABSTRACT FROM AUTHOR]

Opera has gone from a cherished vehicle for royal and aristocratic socializing to a forum for cultural experiences open to everybody. At least for those of us who can afford a ticket. This paper presents findings regarding the transition of audience revenues from the renting out of boxes and seats for all performances during one season to the aristocracy to a much larger share of tickets sold for single performances to a more general audience. Although it was a long, drawn-out process, it seems that the French Revolution was a tipping point not only for the French opera houses, but for those in other European countries as well. Possible pull factors for the much increased bourgeoisie demand are discussed. They include the general economic growth, stable ticket prices, technological evolution, changes in repertoire, the social identification factor, conspicuous consumption, and the new ‘celebrity industry’. This story is told based on primary data collected in the archives belonging to the Opéra National de Paris, Kungliga Operan in Stockholm, Théâtre de la Monnaie in Brussels, Teatro Regio in Turin and Königliche Preussische Hofoper in Berlin. Secondary sources are used to describe what occurred in opera venues in London. The paper also includes information on how seats were sold, who rented boxes annually, box office revenues and on the share of these revenues in the opera revenues. The study ranges from 1750 to 1824. [ABSTRACT FROM AUTHOR]

In this paper, an 8-DOF model including driver seat dynamics, subjected to random road disturbances is used in order to investigate the advantage of active over conventional passive suspension system. Force actuators are mounted parallel to the body suspensions and the driver seat suspension. An optimal control approach is taken in the active suspension used in the vehicle. The performance index for the optimal control design is a quantification of both ride comfort and road handling. To simulate the real road profile condition, stochastic inputs are applied. Due to practical limitations, not all the states of the system required for the state-feedback controller are measurable, and hence must be estimated with an observer. In this paper, to have the best estimation, an optimal Kalman observer is used. The simulation results indicate that an optimal observer-based controller causes both excellent ride comfort and road handling characteristics. [ABSTRACT FROM AUTHOR]

This paper mainly discusses the application of Newmark's theories of communicative and semantic translation in automobile advertisement translation. After analyzing the translation examples of automobile advertisement text, title and trademark, the following conclusions are naturally drawn. The combination of communicative and semantic translation can guide translation practice more effectively. Semantic translation theory is preferred for automobile manual translation, while communicative translation theory is more suitable for automobile brand and slogan translation. Therefore, in order to achieve the intended effect of automobile advertisement, it is better to combine semantic translation with communicative translation in automobile advertisement translation. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to: 1) Explore the mobility experiences of seniors with slow walking speeds (SSWS) in urban neighborhoods; and 2) Investigate their environmental barriers and supports. Methods: Go-along interviews were conducted with 36 SSWS residing in urban neighborhoods of Chongqing City, China. The mobility patterns and built environment factors influencing their mobility were revealed through cartographic analysis and thematic analysis. Results: SSWS primarily focused their activities within a 400-meter radius of their homes. Built environment themes included topography, neighborhood services, sidewalks, seating, traffic safety, weather, greenery, and lighting. Significant mobility barriers included long stairs, steep slopes, fast-moving objects on sidewalks, road crossings, and fast traffic. Available handrails, nearby food-service places, ample seating, and greenery were identified as supportive factors for their mobility. Conclusion: This study stands out as the first to specifically examine the mobility of SSWS within the built environment. We suggest that SSWS should be taken into account when establishing a benchmark for general design frameworks. These improvements not only contribute to the mobility of slow walkers but also have positive impacts on the broader population. [ABSTRACT FROM AUTHOR]

This document is a personal account of Jerry Ericksen's family perspectives, as told by his daughter Lynn Cadmus and son Randy Ericksen. Lynn recalls fond memories of her father teaching her about nature, swimming, and making meal times fun. Randy reflects on their father's diverse range of interests, including mathematics, mechanics, smoking a pipe, watching television, and collecting various items. Both Lynn and Randy express admiration for their father's accomplishments and the impact he had on others in his field. [Extracted from the article]

In this paper, an application of speaker identification in automobile industry is proposed. The work is divided into two main categories. The first part deals with the task of speaker identification where a system is trained and tested for multiple users using a database of isolated Hindi digits and Hindi sentences. A hybrid new algorithm is used for speaker identification which captures the benefits of both LPC and MFCC feature extraction technique. The new proposed technique shows an improvement of 2.05% over conventional MFCC features for isolated Hindi digits and 12.41% for Hindi sentences. It also shows an improvement of 53.26 over LPC for Hindi sentence and 32.51% for isolated Hindi digit over LPC. The proposed features were also tested for real time noisy environment by adding speech and F16 noise to test voice samples with varying degree of distortion starting from 0 to 20 dB. The second part describes the interfacing techniques and design of the hardware configuration for seat adjustment. The proposed model is designed using MATLAB. Speech samples from users are recorded through a microphone. Different features of this wav file are evaluated and fed into the model generated during testing phase. Depending on outcome from the classifier, a user is identified. Once the user is successfully identified, signals are sent to the servo motor through arduino microcontroller interfaced through MATLAB to automatically adjust the driver's seat. [ABSTRACT FROM AUTHOR]

In this paper, a full life cycle resource consumption model for automotive seats has been proposed based on the vehicle material-energy-pollution assessment model, and an assessment on energy consumption and abiotic depletion potential (ADP) impact is conducted to evaluate the power seat environmental performances of a representative passenger car from the standpoint of life cycle. The results show that the energy consumption of the selected automotive seats mainly occurs in the use phase. Among all types of energy consumption, the non-renewable energy consumption is much larger than the renewable energy consumption. According to the ADP impact assessment, the consumption of copper and crude oil makes the largest contribution to resource depletion, and the ADP index may increase significantly due to the additional electrical part of car seats. Therefore, the enhancement of environmental performances of car seats can be achieved through measures including design with lightweight metal, fuel-electric conversion efficiency improvement, reduction in energy consumption caused by seat motor running and a more sustainable material with low ADP coefficient. [ABSTRACT FROM AUTHOR]

This paper presents a novel, simple and reliable control strategy for an active seat suspension, intended for use in a vehicle, which attenuates the harmful low-frequency vertical vibration at the driver’s seat. An advantage of this strategy is that it uses measurable preview information from the vehicle suspension. The control force is calculated from this preview information and controller gains obtained by optimising an objective function using a genetic algorithm (GA) approach. The objective function optimises ride comfort in terms of the Seat Effective Amplitude Transmissibility factor, taking into account constraints on both the allowable seat suspension stroke and actuator force capacity. This new controller is evaluated using both simulation and experimental tests in both the frequency and time domains. The simulation model is based upon a linear quarter vehicle model and a single degree of freedom seat suspension. Experimental tests are performed using a multi-axis simulation table and an active seat suspension. Finally, the performance of the active seat suspension is analysed and compared to a passive system, demonstrating significant acceleration attenuation of more than 10 dB across a broad frequency range. Consequently, this has the potential to improve ride comfort and hence reduce the driver’s fatigue using a reliable and cost-effective control method. [ABSTRACT FROM AUTHOR]

Wheel-rail force is a critical parameter for vehicle-track-bridge (VTB) structure system, playing a pivotal role in ensuring the safe operation of trains and service performance of track and bridge structures. This paper proposes a methodological framework for efficient and accurate prediction of wheel-rail force, that bidirectional gated recurrent unit (Bi-GRU) neural network is developed and the hyperparameters of networks are optimized through grey wolf optimization (GWO). Based on the developed VTB system model, numerical experiments are carried out to produce datasets which are verified through field test. In order to make the data more universal and comprehensive, Latin hypercube sampling (LHS) is introduced to randomize the parameters of VTB model. The datasets generated from VTB system, with rail seat force as input and wheel-rail force as output, serve as the training data for framework. Additionally, the inversion effects under various working conditions are examined and discussed. The results indicate that the model can precisely inverse continuous wheel-rail forces from the moment the wheels enter the first test rail seat until leave the last test point of rail seat. When the neural network learns from the features of at least three or more rail seats on each track slab (with intervals not exceeding 2 rail seats), it can accurately inverse the time history curve of wheel-rail forces. The framework presents a viable alternative for the wheel-rail force analysis, and promising potential for the realization of online monitoring of wheel-rail force. • A vehicle-track-bridge coupling model based on random parameters of Latin hypercube sampling is established. • The FBG sensor is embedded into ballastless track sleeper for monitoring rail seat force and model verification. • The GWO-Bi-GRU framework is proposed to invert the wheel-rail force. • The inversion effect of the framework under different working conditions is discussed. • A novel method for monitoring wheel-rail vertical force was proposed. [ABSTRACT FROM AUTHOR]

This paper presents a new hybrid controller which is a combination of three control schemes: fuzzy neural control, PI control and sliding mode control. The interval type 2 fuzzy model featuring updated rules via online is used in this study and in order to support the fuzzy model, a granular clustering method is applied to find groups of data related to the initial fuzzy rule. Then the output for fuzzy model is used for the PI-sliding mode controller. The combination of PI and sliding mode controls is carried out by H-infinity technique method which is rely on the modified Riccati-like equation. After developing the mathematical model, the proposed controller is applied to vibration control of a vehicle seat suspension featuring magneto-rheological (MR) damper. In order to demonstrate the effectiveness of the proposed controller, two different excitations of bump and random signals are adopted and corresponding vibration control performances are evaluated. It is demonstrated through both simulation and experiment that the proposed controller can provide much better than vibration control performance compared with the conventional controllers showing more robust stability. [ABSTRACT FROM AUTHOR]

The aim of the study is to compare the head displacement of the KPSIT C50 dummy during a frontal collision at a speed of 20 km/h, along with the change in the angle of the car seat backrest. Passenger car manufacturers recommend setting the backrest angle of the car seat between 100 and 125 degrees. It should be noted that the driver's position is of great importance in the event of a collision injury. In the event of a rear-end collision, the position of the headrest of the car seat is an element that affects the degree of the driver's injuries. In extreme cases, incorrect positioning of the headrest, even at low speed, can lead to serious injuries to the cervical spine and even death. The article is part of a large-scale study on low-speed crash testing. The research problem concerned the influence of the seat backrest angle on the head displacement during a low-speed collision. The article compares the displacement of the head of the KPSIT C50 dummy during a series of crash tests, where the angle of the car seat backrest was changed. On the basis of the research, it was found that the optimal angle of the car seat backrest is 110 degrees. In addition, a preliminary analysis of the displacements of the dummy's head showed a high risk of whiplash injury in people sitting in a fully reclined seat. [ABSTRACT FROM AUTHOR]

This study investigates inter-island accessibility in the Azores Islands (Portugal), a region marked by unique territorial fragmentation and significant distances between islands. Recognizing the pivotal role of sea and air transport in fostering the socioeconomic development of the archipelago by enhancing resident mobility and attracting tourism, we address the challenges posed by the region's low demographic and economic influence and the pronounced imbalances among islands. The methodological approach involves the examination of various accessibility parameters, with a specific focus on hourly operations identified as presenting the most unfavorable ratios of time availability in the destinations. We analyze inter-island sea and air schedules during the winter season, emphasizing their relevance for residents engaged in travel for business, health, administration, and related purposes. We have mainly analyzed the air schedules since it was possible to make the round trip on the same day on only two maritime routes, although these have also been considered. Regarding the study outcomes, they reveal that despite positive efforts to implement air public service obligations (PSO), which mandate specific frequencies, seat allocations, and rate caps, among other examples, the limited attention given to adapting operating hours based on demand undermines the effectiveness of these measures. Contextually, this lack of adjustment results in substantial inconvenience for travelers, particularly those engaged in round-trip operations on the same day, a common scenario in inter-island mobility. In more than 70% of the operational routes, suitable travel times at the destination are significantly compromised. [ABSTRACT FROM AUTHOR]

This article seeks to understand the circumstances under which minoritized women are descriptively represented. Drawing from a unique dataset of 7,978 legislators in 37 countries, we conduct the first cross-national examination of minoritized women's representation at the level of individual legislators. We find that gender quotas, ethnic parties, and ethnic seats are effective at enhancing minoritized women's political representation across different electoral systems, especially when clustered together. And, although ethnic parties and ethnic seats promote the representation of both minoritized women and men, ethnic seats provide a more level playing field between minoritized women and men than ethnic parties. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of robust H∞ reliable load-dependent control design for a class of semi-active seat suspension systems. A four degree-of-freedom human body model is considered in order to investigate the control strategy more precisely. It is assumed that the human body mass resides in an interval and can be measured online. The load-dependent approach is based on a parameter-dependent Lyapunov function. Thus the proposed method is capable of reducing the conservatism and improving the closed-loop performance. Actuator faults are also considered in the controller design process and the resulting control systems are reliable because they provide guaranteed asymptotic stability and H∞ performance in spite of the possible actuator failures. The usefulness and advantages of the controller design methodology are demonstrated through a design example. [ABSTRACT FROM PUBLISHER]

This paper deals with the issues of the impact of vertical vibrations on a child seated in a child seat during a journey. Its purpose was to assess the impact of fastening the child seats and road conditions on the level of vibrations recorded on child seats. The paper describes the tested child seats, the methodology of the tests and the test apparatus included in the measuring track. The tests were carried out in real road conditions where the child seats were located on the rear seat of a passenger vehicle. One was attached with standard seat belts, and the other with the ISOFIX base. When driving on roads with three types of surface, the following vertical accelerations were measured: seat of the child seats, the rear seat of the vehicle and the ISOfix base. The recorded accelerations were first analyzed in the time domain and then in the frequency domain. Three indexes (r.m.s, rmq and VDV) were used to assess the vibration comfort. Research has shown that the classic method of fastening a child seat with standard seat belts is more advantageous in terms of vibration comfort. Calculated indicators confirmed the negative impact of separating the child seat from the rear seat of the vehicle using the IQ ISOFIX base. [ABSTRACT FROM AUTHOR]

Ford Motor Company has developed a corporate engineering test procedure focused on the vibration transmissibility of the occupied automotive seat. The procedure allows Ford to assess, in a consistent manner, the performance of (1) prototype-level seats specific to new/future programs and (2) production-level competitive seats. As part of the procedure, a complete seat system is mounted to a human-rated platform using a dedicated fixture, engaged by persons matching specific anthropometric characteristics, and excited vertically, laterally, and fore-aft with external actuators under laboratory conditions. Johnson Controls is one of the few seat suppliers that have the equipment and expertise required to execute this procedure. Using Ford's procedure, the objective of this paper is to compare and contrast the test results, expressed both statistically and graphically as transfer functions, produced by these two independent facilities. Because of the proximity of the two laboratories, it was possible to use the same production level seat and the same occupants at both facilities. The results showed good agreement in all excitation directions. Based on the strength of these results, discussions concerning specific noise, vibration and harshness (NVH) and ride quality requirements, which Ford cascades to Johnson Controls on a program-by-program level, can begin from a common basis. The common understanding, while yielding a more efficient seat development process, should lead to more comfortable vehicles. [ABSTRACT FROM AUTHOR]

Suspension seats are widely used in heavy vehicles to reduce vibration transmitted to human body and promote ride comfort. Previous studies have shown that the dynamics of the suspension seat exhibits nonlinear behaviour with changed vibration magnitudes. Despite various linear seat models developed in the past, a nonlinear model of the suspension seat capturing the nonlinear dynamic behaviour of the seat suspension and cushion has not been developed for the prediction of the seat transmissibility. This paper proposes a nonlinear lumped parameter model of the suspension seat to predict the nonlinear dynamic response of the seat. The suspension seat model comprises of a nonlinear suspension submodel integrated with a nonlinear cushion submodel. The parameters of the submodels are determined by minimizing the error between the simulated and the measured transmissibility of the suspension mechanism and the force-deflection curve of the seat cushion, respectively. The model of the complete seat is then validated using the seat transmissibility measured with inert mass under vertical vibration excitation. The results show that the proposed suspension seat model can be used to predict the seat transmissibility with various excitation magnitudes. [ABSTRACT FROM AUTHOR]

The comfort of a car seat depends on many parameters of the seat and the characteristics of the people sitting on it. The paper deals with the innovation of a measuring device for testing car seats in laboratory conditions. The device now makes possibility to realize the vertical movement of the car seat and both the horizontal movement in two directions front-rear and left-right. The vertical movement can realized separately or simultaneously with the horizontal movements. Dependent or independent excitation in all three axes perform laboratory testing automobile seats same as when driving a real car. The advantage of laboratory testing is very good repeatability of tests. Long-term durability tests also should be performed in laboratory conditions in a 24-hour testing mode. [ABSTRACT FROM AUTHOR]

Customers' expectations for a consistent long-term high-level product performance have been increasing year after year, and the automotive industry is leading the trend. As an automotive seating component, polyurethane foam has a direct impact to the perceived value of an occupant, thus providing high durability foam became essential to customer satisfaction. Many tests were developed to evaluate the foam durability in various environments because of the importance of durability. The data used to correlate the results from these tests to that of foam collected from the used vehicles is limited because of the complex nature of aging and usage. In this study, newly manufactured foams were aged at a high temperature, and their fatigue properties were compared with the properties of foam samples collected from the vehicles of different mileage, age and geographical location. The results of this study showed that the heat aging at 100°C can be used to estimate the aging condition in a dry, hot climate with approximate mileage of 139,000 miles. However, varying the heated time of the foam for accelerated aging did not vary the fatigue property significantly enough to correlate to different mileage. Instead, an application of weight during the heating process is found to represent the fatigue property of foam at higher mileage than heat aging alone. Although the level of wear of the foam was found to be different depending on the environmental conditions, 25% compression load deflection (CLD) value before and after repeated compression of all samples of the same size were found to follow a logarithmic relationship. Further study of foam with different levels of wear are necessary for more detailed observations. [ABSTRACT FROM AUTHOR]

In general, cold-cured flexible foams have a high content of closed cells during a foaming process because of a high reactivity of foaming components and curing at a low temperature. Cold-cured flexible foams require a mechanical method such as roll crushing or vacuum crushing to open a high content of closed cells for preventing shrinkage and cracking of foam after demolding. But this mechanical crushing process can yield foams with poor properties and reduce productivity on account of increasing costs for utilities, electricity, manpower and repair. A noncrushing foam system developed by Kumho Mitsui Chemicals Inc. (hereafter referred to as "KMCI") is a new cell opening technology that makes complete cell opening during the foaming process. Thus, this technology results in no shrinkage and cracking after demolding. In addition the noncrushing foam system makes possible manufacturing automotive seat cushions having an open cell structure and excellent cell stability compared to conventional foam by minimizing the degree of cross-linking density and increasing urea linkage. Our new technology has been used to make seat cushion at Hyundai Motor Company in Korea since 1999. We expect that the noncrushing foam system will be applied in various flexible foam applications and will contribute to improvement of productivity and seat cushion quality. [ABSTRACT FROM AUTHOR]

• The effects of design parameters and their interactions on the transmissibility. • The regression relationship between the transmissibility and input design parameters. • The response surface method (RSM) model validated by analysis of variance. • The RSM modelling and Genetic Algorithm applied to optimize the design. • Identify the parameters of seat suspension system from field vibration measurement. Low-frequency vibration is a significant hazard to commercial vehicle drivers. Research on how to reduce seat vibration and improve human comfort in a seating system through seat design optimization is important. The novelty of this paper is to study the sensitivity analysis of seat design parameters and their interaction effects and optimize seat design for the minimum vibration transmission to human drivers. The uniqueness of this paper is the identification of the system parameters from the measured vibration acceleration data rather than from the material test. The purpose of this paper is to develop a prediction model of vibration transmissibility from input design parameters using the response surface method modeling. The statistical significance of the RSM model will be validated by analysis of variance. The design parameters will be optimized through the RSM modeling and Genetic Algorithm. The method can enhance the vibration isolation performance of the existing vehicle seat suspension system with reduced cost and without additional parts and energy consumption and make the design change and optimization of the seat suspension system simple and easy to be implemented. According to the research results, the vibration transmissibility ratio of the optimized seat system is reduced by about 10%. [ABSTRACT FROM AUTHOR]

The introduction of automated L5 driving technologies will revolutionise the design of vehicle interiors and seating configurations, improving occupant comfort and experience. It is foreseen that pre-crash emergency braking and swerving manoeuvres will affect occupant posture, which could lead to an interaction with a deploying airbag. This research addresses the urgent safety need of defining the occupant's kinematics envelope during that pre-crash phase, considering rotated seat arrangements and different seatbelt configurations. The research used two different sets of volunteer tests experiencing L5 vehicle manoeuvres, based in the first instance on 22 50th percentile fit males wearing a lap-belt (OM4IS), while the other dataset is based on 87 volunteers with a BMI range of 19 to 67 kg/m2 wearing a 3-point belt (UMTRI). Unique biomechanics kinematics corridors were then defined, as a function of belt configuration and vehicle manoeuvre, to calibrate an Active Human Model (AHM) using a multi-objective optimisation coupled with a Correlation and Analysis (CORA) rating. The research improved the AHM omnidirectional kinematics response over current state of the art in a generic lap-belted environment. The AHM was then tested in a rotated seating arrangement under extreme braking, highlighting that maximum lateral and frontal motions are comparable, independent of the belt system, while the asymmetry of the 3-point belt increased the occupant's motion towards the seatbelt buckle. It was observed that the frontal occupant kinematics decrease by 200 mm compared to a lap-belted configuration. This improved omnidirectional AHM is the first step towards designing safer future L5 vehicle interiors. [ABSTRACT FROM AUTHOR]