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In this paper we considered the problem of an s-shaped acceleration/deceleration curve constructing in real time with linear-spline interpolation, taking into account given constraints on the contour acceleration, jerk, and feed rate. The input data for the s-curve were defined in the lookahead algorithm and the geometric smoothing module. The choice of a particular acceleration/deceleration strategy depends on the segment length, the allowable feed rates at the segment junction, and the given kinematic constraints. Each trajectory segment can have a maximum of seven time intervals and their rounding will produce inaccuracies when forming the velocity profile. Therefore, to compensate for rounding errors, the method of half division was applied, which made it possible to remove gaps in the velocity contour. The experimental data obtained indicate the correctness of the chosen approach for its implementation as part of the CNC for high-speed machining of surfaces with complex shapes. Key words Feed-rate planning algorithm, s-shaped acceleration/deceleration, trajectory smoothing, numerical control system, real-time, frame preview algorithm. Acknowledgements The research was carried out with financial support of Ministry of Science and Higher Education of Russian Federation in the frame of state assignment (project no.FSFS-2020-0031).

In general, NC programs for machining free-form surfaces using a computer numerical control (CNC) machine tool are generated using a computer-aided manufacturing (CAM) system. The tool paths (CL data) generated by a CAM system are approximated straight-line segments based on tolerance (allowable error). As a result, the tolerance affects the machining accuracy and time. If the tolerance is set to a small value, the lengths of the segments are shortened, and the machining accuracy is improved. The process in which a CNC machine tool reads and analyzes an NC program and controls the motors requires a minimum processing time of an NC program block (block-processing time). Therefore, if the lengths of the approximated straight-line segments are too small, it will be impossible to reach the indicated feed speed, and the machining time will be longer. In this study, by identifying the block-processing time of a CNC controller and deriving the appropriate length of the approximated straight-line segment based on the block-processing time, a CL data creation method that is capable of high-speed and high-accuracy free-form surface machining is proposed. In addition, experimental verification tests of the method are conducted.

The paper presents results of unsolicited exploratory design studies done by the authors into the feasibility of developing for a super-heavy launch vehicle a single-stage oxygen-hydrocarbon acceleration/deceleration unit (ADU) with two liquid-propellant rocket engines 11D58M developed by RSC Energia, intended for insertion of manned spacecraft into lunar orbit, as well as for insertion of super-heavy spacecraft into geostationary orbit (including the orbital module high-apogee transfer profile using lunar gravity assist maneuver). It demonstrates that the single-stage ADU will have a number of important advantages over both a single-stage oxygen-hydrogen ADU and a functionally similar two-stage acceleration/deceleration system of an orbital module in the form of a tandem stack of an oxygen-hydrogen acceleration stage and correction and braking stage. To assure the start-ups of the main liquid propulsion system of the ADU, it proposes a new method for inertial propellant component phase separation in the tanks in zero-gravity environment using a pre-startup pre-programmed ullage separation turn maneuver of the orbital unit about its transverse axis of inertia.

Optimization studies of feed drive system parameters of machine tools are gaining attention. Majority of the studies use the weighted sum of several evaluation indices regarding machine behavior as the objective function. However, there is no clear guideline for designing those weights, which are currently configured empirically. To address this problem, this study has optimized acceleration/deceleration parameters of a milling table with various weight configurations by using a machine tool simulator. Optimized parameters showed clear relationships between the weights related to the magnitude of acceleration and the positional accuracy. That enables weight configuration design to meet various users’ needs.

The objective of this paper is to empirically investigate drivers’ decision zones at the onset of flashing green and yellow indication at rural high-speed intersections in China. 1122 high-resolution trajectories of the first-to-stop and the last-to-go vehicles during the phase transition time period were collected at four intersection approaches in Shanghai. Speed-Distance (S-D) diagram and Acceleration-Deceleration (A-D) diagram were then used to analyze the distribution of drivers’ decision zones in response to the onset of flashing green and yellow respectively. The former is a conventional approach based on a fundamental assumption that no drivers would accelerate to cross or make an abrupt stop. The latter is a more flexible method based on the required acceleration rate to cross and the required deceleration rate to stop which can be extracted from vehicle trajectory data. Results support that the installation of flashing green helps to reduce the dilemma zone according to the A-D diagram. There are limits when using S-D diagram to analyse the driving situations based on G.H.M model.

Objective: This study aimed to determine the effect of music that was listened to by pregnant women during the non-stress test (NST) on the test result and maternal anxiety. Materials and methods: The study utilized a non-randomized controlled trial design. Sequential sample selection method was used. The pregnant women in the experimental group listened to music during the NST (20 min). Results: There were significant differences between the two groups in terms of mean numbers of acceleration deceleration and reactive NST results (p = 0.001). There were statistically significant differences between the intergroup mean scores of pre- and post-music in favor of the control group (p = 0.001). Conclusion: This study concluded that music is an effective method of reducing pregnant women's deceleration numbers and increasing their acceleration numbers and reactive NST rates. The use of music during NSTs can be recommended. © 2019 Elsevier Ltd, Ministry of Health Firat University Scientific Research Projects Management Unit: 2018–16, The purpose of the study was explained to each pregnant woman, and their consent was obtained. The research ethics committee approval numbered 2015-KAEK-86/12–107 was obtained from the Dumlupınar University Ethics Committee in Clinical Research. The research permit numbered 5571989/604.02 was issued by the General Secretary of the Turkish Public Hospitals Agency of Kutahya Province under the Ministry of Health. Permission to use the STAI was obtained from Necla Oner, who translated the scale into Turkish. 3, This study was funded by the Dumlupınar University Scientific Research Projects Commission (Award Number 2018–16 ).

Background The fetal heart rate (FHR) serves as a guide to fetal well-being during the first stage of delivery. The visual morphological analysis of the FHR during labor is subject to inter- and intra-observer variability – particularly when the FHR is abnormal. It has been suggested that automatic analysis of the FHR can reduce this variability. Objectives To compare 11 morphological FHR analyses (baseline computation, and detection of FHR decelerations and accelerations) produced by automatic analysis methods (AAMs) with an expert consensus. Materials and methods Eleven AAMs were reprogrammed (using the description published in the literature) and applied to 90 FHR recordings collected during the early phase of labor. Furthermore, the recordings were divided into three tertiles, according to the difficulty of analysis. The results of the morphological FHR analyses produced by the AAMs were compared with a consensus morphological analysis performed by four experts. In addition to standard discriminant criteria, a new morphological analysis discriminant index (MADI) was introduced; it provides an overall evaluation that collates all the individual criteria. Results The AAM developed by Lu and Wei's gave better results than the other AAMs for baseline computation. Regarding this method's detection of FHR decelerations and accelerations, the F-measure [95% confidence interval] was respectively 0.73 [0.67; 0.76] and 0.70 [0.64; 0.76]. The MADI indicated that Lu and Wei's AAM agreed best with the expert consensus (discordance: 7.3% [6.10; 8.60]). Conclusion Our study demonstrated the superiority of Lu and Wei's method for baseline computation and deceleration/acceleration detection, although there was still a significant degree of discordance versus expert consensus. The MADI appears to be a good overall index for evaluating AAMs with regard to the quality of baseline computation and acceleration/deceleration detection. The application of precise criteria and the methodology and software tools developed here should facilitate the evaluation of new AAMs and their comparison with other methods.

This study described the decrement in accelerations, decelerations and dynamic stress load (DSL) between quarters in elite hurling. GPS (10-Hz) were used to record data from 42 players over 22 games (2018&ndash, 2020 season). The number of accelerations and decelerations and DSL between quarters were assessed. Accelerations and decelerations were greater in Q1 than Q2 (ES = 0.28 and ES = 0.44, respectively), and Q4 (ES = 0.57 and ES = 0.60, respectively), and in Q3 compared to Q4 (ES = 0.50 and ES = 0.44, respectively). The DSL was 56 &plusmn, 21 AU in Q1, 56 &plusmn, 20 AU in Q2, 52 &plusmn, 20 AU in Q3 and 56 &plusmn, 24 AU in Q4. There was a decrease in DSL in Q3 compared to Q1 (ES = &minus, 0.20) and Q2 (ES = &minus, 0.20). Each position experienced a temporal decrease in at least one quarter (ES = 0.43&ndash, 1.46) in all metrics except full-backs&rsquo, half-backs&rsquo, and full forwards&rsquo, accelerations, midfielders&rsquo, decelerations and midfielders&rsquo, and half forwards&rsquo, DSL. Current data show temporal decrements in running performance in Q2 and Q4 and DSL in Q3. Players should be conditioned to minimize the drop-off in running performances following the third quarter.

This paper proposes a mathematical model to regulate the acceleration (deceleration) applied by self-driving vehicles in car-following situations. A virtual environment is designed to test the model in different circumstances: (1) the followers decelerate in time if the leader decelerates, considering a time delay of up to 5 s to refresh data (vehicles position coordinates) required by the model, (2) with the intention of optimizing space, the vehicles are grouped in platoons, where 3 s of time delay (to update data) is supported if the vehicles have a centre-to-centre spacing of 20 m and a time delay of 1 s is supported at a spacing of 6 m (considering a maximum speed of 20 m/s in both cases), and (3) an algorithm is presented to manage the vehicles’ priority at a traffic intersection, where the model regulates the vehicles’ acceleration (deceleration) and a balance in the number of vehicles passing from each side is achieved.

The design of an optimal rack for 3D multi-deep AS/RS under full turnover-based storage policy is explored in this paper. The acceleration and deceleration characteristics of storage and retrieval (S/R) machine are considered based on non-approximate speed model of S/R machine. We divided three typical scenarios to investigate. With regards to each scenario, we derive the expected retrieval time for single-command cycles adopting exact speed model and develop the model for optimally designing 3D multi-deep AS/RS rack. From the model, we can derive the optimal rack dimensions for various scenarios more precisely. Our findings are demonstrated by a practical example.

The acceleration/deceleration feedrate scheduling is one of the most important techniques in computer numerical control systems. Along with this technique, the bi-directional scanning technique is always employed. The bi-directional scanning technique consists of a backward scanning process followed by a forward scanning process. The two scanning processes in the conventional methods are executed in a serial manner by scanning through all the scheduling blocks one by one. Consequently, the feedrate scheduling will suffer from a heavy computational burden when there are massive blocks to be scanned, which deteriorates its real-time performance for computer numerical control machining. To alleviate the computational burden, a parallel acceleration/deceleration feedrate scheduling approach is proposed in this article. With this method, the scheduling blocks are splitted into several scheduling units and the feedrate for each of them is scheduled simultaneously. The feasibility of the proposed approach is validated through the feedrate scheduling for two widely used butterfly and helix paths. For a constructed example of feedrate scheduling, a significant acceleration ratio about 3.7 on a personal computer with a quad-core central processing unit is achieved.

The J-turn, also known as the restricted crossing U-turn and Superstreet, is an innovative geometric design that can improve intersection safety. Although this design has been in use in several states for many years, there is very little research-based guidance for several design parameters. A driving simulator study was conducted to analyze the parameters of lane configuration, U-turn spacing, and signage. Two lane configurations were examined: ( a) an acceleration–deceleration configuration, in which acceleration and deceleration lanes are provided, and ( b) a deceleration-only configuration, in which only deceleration lanes are provided. Lane configuration was found to be the most important parameter affecting J-turn safety according to speed differentials. The only significant interaction effect among parameters was between lane configuration and U-turn spacing. The acceleration–deceleration configuration performed better than the deceleration-only configuration, having 66.3% fewer safety critical events. Vehicle trajectories and average lane change locations showed that U-turn spacing significantly affected the acceleration–deceleration configuration (e.g., average merge locations changed by 96% to .0101%) but not the deceleration-only configuration. No strong preference was demonstrated for either the directional or the diagrammatic signage style. This paper presents one of the first human-factors studies of the J-turn to focus on developing design guidance. This human-factors approach complements traditional approaches such as crash analysis and microsimulation.

This chapter examines two patterns of change seen in individual offending behaviors at certain times and ages: acceleration or deceleration and escalation or de-escalation. In order to answer the questions regarding the age–crime curve and its applicability to the criminal careers of specific individuals, the prevalence of offending in the population and the frequency of offending within individual criminal careers must be examined through these patterns. Hence, the chapter begins with a brief review of the origin of the criminal career paradigm and a description of its various parameters. It then discusses both static and dynamic developmental and life-course theories of crime before providing a more in-depth discussion of acceleration/deceleration and escalation/de-escalation as it relates to a criminal career, respectively. Finally, this chapter concludes by offering directions for future research on these topics.

Case report A 59-year-old male with acceleration/deceleration cranial trauma (ADT), caused by a car accident. After one month, he presented with loss of visual acuity in the right eye. A fluorescein angiography test was performed and it detected centrifugal hyperfluorescent lines from the optic nerve head, a characteristic compatible with the diagnosis of angioid streaks. The loss of visual acuity was demonstrated by the discovery of a juxtafoveal choroidal neovascular membrane (CNV). Conclusion ADT can cause hyper-extension of the eyeball in its equator line, producing the rupture of fragile structures such as the Bruch membrane (MB) in patients with angioid streaks and the subsequent formation of CNV.

To improve the sorting accuracy and efficiency of sorting system with large inertia robot, this article proposes a novel trajectory planning method based on S-shaped acceleration/deceleration algorithm. Firstly, a novel displacement segmentation method based on assumed maximum velocity is proposed to reduce the computational load of velocity planning. The sorting area can be divided into four parts by no more than three steps. Secondly, since the positions of workpieces are dynamically changing, a dynamic prediction method of workpiece picking position has been presented to consider all the possible positions of the robot and the workpiece, so as to realize the picking position prediction of the workpiece at any positions. Each situation in this method can constitute an equation with only one solution, and the existence of the solution can be verified by the proposed graphical method. The simulations of the motion time of the sorting process show that the proposed method can significantly shorten the sorting time and improve the sorting efficiency compared with the previous method. Finally, this method was applied to the Selective Compliance Assembly Robot Arm (SCARA) robot for experiments. In the physical picking experiment, the missing-pick rate was less than 1%, which demonstrates the efficiency and effectiveness of this method.

An increasing number of smartphone apps with driving safety diagnosis functions have been developed in the market; however, empirical evidence on whether these apps are actually effective i...

Based upon ethnographic data gathered in Shanghai, this paper explores residents’ experiences of, and responses to, living within an environment, which displays features of what Rosa terms ‘social acceleration’. After exploring anxieties induced in residents who feel sedentary – relative to others – and their attempts to cope with this, this paper focuses upon how residents’ attitudes towards social acceleration become refracted in imaginative forms, especially texts currently circulating within Shanghai, which insinuate ostensibly supernatural characters into certain prominent locations in the city. As these texts critique ‘progress’ and register residents’ anxieties regarding social acceleration so they smooth over disquiet and unease thereby encouraging not only discourses of development but also the patterns, pace and tempo of social acceleration. The final part of this paper explores the costs of ‘slowdown’, arguing these are sufficient to compel residents not only to re-engage with, and therefore perpetuate, socially accelerating forms but perhaps even to intensify them, hence the deployment of the term ‘re-acceleration’ in the title of this paper.

The Acceleration/Deceleration (AD) feedrate scheduling is widely used to plan the feedrate for CNC machining. Since the toolpath in CNC machining consists of enormous blocks (e.g., G01 or G02 block), the AD scheduling will result in lots of successive feedrate profiles. The feedrate at the junction of the adjacent profiles can be discontinuous, which will saturate the actuator and deteriorate the machining performance. The Bi-Directional Scanning Method (BDSM) is used to make the profiles overall continuous. To alleviate the computational burden, the BDSM is usually applied within a look-ahead buffer. When the buffer is filled with feedrate profiles, the BDSM updates the feedrates in the buffer. Conventional works believe that the BDSM with look-ahead (BDSMLA) will only increase the feedrate in each updating and is always feasible. We find that the BDSM can, however, decrease the feedrates in the buffer. The feedrate decrease will result in overall feedrate discontinuity and make the BDSM infeasible. We also propose a tweak method which can guarantee the feasibility of the BDSMLA. Simulation reveals the feedrate decrease in the BDSMLA and verifies the effectiveness of the tweak method.

This paper explores the optimal storage rack design for a multi-deep compact Automated Storage and Retrieval System (AS/RS) considering the acceleration and deceleration of storage and retrieval (S/R) machine. The expected travel time under the single-command cycle and dual-command cycle for a random storage strategy is derived. Based on the travel time, the general models we propose calculate the optimal ratio between three dimensions that minimises the travel time under different speed profile scenarios. From the result, it is proven that the optimal storage rack design model in the constant speed situation can be treated as a special case of the model considering the acceleration and deceleration of S/R machine. Finally, this study investigates the effect of speed profile of S/R machine and fixing dimensions by various numerical experiments.

To overcome some shortcomings of the linear Acc/Dec approach and the traditional S-curve Acc/Dec method, a novel velocity planning approach is proposed for CNC machine tools in this paper. The velocity planning model based on moving average technology is structured. The presented approach is used to make velocity planning for the CNC system. Comparing with the linear Acc/Dec algorithm, the presented method greatly improves motional smoothness of the linear Acc/Dec approach and reduces the complexity of the traditional S-curve Acc/Dec algorithm, which is more suitable for high-speed and high-precision CNC machine tools. The proposed approach is tested by simulation and experimentation. Simulation and experimental results have shown that the proposed method can significantly improve the motional smoothness and consumes less resource and shortens processing time for the CNC system.

The acceleration can be controlled using S-curve acceleration/deceleration algorithm in motion process and the impact of system is decreased in the stage of start or stop. So the S-curve is widely used in CNC or robot system. At present, most acceleration/deceleration algorithms are achieved in PC using strong operation ability of CPU, which increase the delay time of PC. So a simple and efficient S-curve acceleration/deceleration algorithm in FPGA is proposed. This algorithm can share the operation press of PC effectively and achieve flexible control of motion control system.

Background: Shoulder pain in general and acromioclavicular joint (ACJ) pain specifically is common after acceleration-deceleration injury following road traffic accident (RTA). The outcome of surgical treatment in this condition is not described in the literature. The aim of the present study was to report the outcome of arthroscopic resection of the ACJ in these cases. Materials and Methods: Nine patients with localized ACJ pain, resistant to nonoperative treatment were referred on an average 18 months after the injury. There were 3 male and 6 females. The right shoulder was involved in seven patients and the left in two. The average age was 38.9 years (range 29-46 years). All presented with normal X-rays but with torn acromioclavicular joint disc and effusion on magnetic resonance imaging (MRI). Arthroscopic ACJ excision arthroplasty was performed in all patients. Results: At a mean followup of 18 month, all patients had marked improvement. The Constant score improved from 36 to 81, the pain score from 3/15 to 10/15 and the patient satisfaction improved from 3.5/10 to 9.3/10. Conclusion: Arthroscopic ACJ excision arthroplasty, gives good outcomes in patients not responding to conservative management in ACJ acceleration-deceleration injury.

The final process of workpiece is composed of a series of connected trajectories, and the expectation speed of the different trajectories may be different, so it requires the changes of acceleration and deceleration speed. This paper introduces the improved acceleration-deceleration algorithm of trigonometric function, and presents an optimization algorithm according to the changing trend of velocity to the method of forward-looking processing speed.

In order to improve inertia identification accuracy of the servo system, this paper proposes an improved acceleration deceleration method which adopts a simplified mathematical model of servo system in rotating coordinate system of servo motor, determines the detection signals which applies for load inertia identification. The experimental results demonstrate that compared with traditional acceleration deceleration method, the improved acceleration deceleration method has significant improvements in the accuracy of inertia identification and thus the study results have a major impact on the improvement of servo system's control performance.

To satisfy the need of high precision numerical control machining, the 5 stage S-type acceleration/deceleration control model is proposed, and the model is established under two conditions of without considering transient acceleration and transient speed and considering the startup acceleration and the transient speed respectively. In order to obtain an optimal speed curve, the control model is solved by the improved genetic algorithm which is a new control algorithm for real-time processing and optimization. The acceleration/deceleration control model is applied to the engineering example, and the results show that the speed curve is in good agreement with the actual project practice. The experimental result proves that the control model is effective.

This paper deals with the passenger ride comfort of electric vehicle. A generation method of speed pattern is proposed for improving the ride comfort against the longitudinal acceleration/deceleration. The speed pattern generated using proposed technique is based on the general optimal control theory with evaluating the acceleration and the jerk which is time derivative of the acceleration. The effectiveness of the present method is demonstrated through numerical experiments.

The development of S-curve acceleration and deceleration (ACC/DEC) algorithms has become important for computer numerical control (CNC) machining in recent decades because it provides smoother feed motions for cutting tools and can thus shorten the machining time, maintain the machining quality, and enhance the tool life. In this study, a quintic feedrate function is developed and applied to realize an S-curve ACC/DEC algorithm with limited values of feedrate, feed acceleration, and feed jerk. This study analyzes the kinematic characteristics of the quintic feedrate function in detail and then develops a systematic scheme to determine the ACC/DEC time by referring to the given feedrate difference, feed acceleration, and feed jerk constrains. Furthermore, several simulations and experiments carried out on a three-axis CNC milling machine demonstrate the feasibility of the approaches developed in this study.

In this paper we investigate a model where travel time is not necessarily proportional to the distance. Every trip starts at speed zero, then the vehicle accelerates to a cruising speed, stays at the cruising speed for a portion of the trip and then decelerates back to a speed of zero. We define a time equivalent distance which is equal to the travel time multiplied by the cruising speed. This time equivalent distance is referred to as the acceleration–deceleration (A–D) distance. We prove that every demand point is a local minimum for the Weber problem defined by travel time rather than distance. We propose a heuristic approach employing the generalized Weiszfeld algorithm and an optimal approach applying the Big Triangle Small Triangle global optimization method. These two approaches are very efficient and problems of 10,000 demand points are solved in about 0.015 seconds by the generalized Weiszfeld algorithm and in about 1 minute by the BTST technique. When the generalized Weiszfeld algorithm was repeated 1000 times, the optimal solution was found at least once for all test problems.

Accurate position control and its related dynamics have been under research for industrial robotics and CNC machinery applications. Several works have developed techniques to fulfil the trajectory planning and profile generation from the CADCAM point of view, however, there is a lack in the mathematical foundations on computationally efficient profile generation for implementation in digital systems. This paper shows a novel approach for acceleration–deceleration profile generation based on polynomials at the discrete-time domain which is computationally efficient and easy to implement in most digital system available technologies. Results in the form of simulations and a servomotor driving the axis position on a CNC milling machine are presented to show the procedure efficiency and jerk reduction. It is shown that the proposed parameterisation of polynomial based profile generation requires half the operations to be computed, compared with the currently available methodologies for direct polynomial evaluation. Furthermore, the proposed procedure is multiplier free which means that almost every low-cost processor or embedded digital system can easily perform the generation task.

This paper introduces an offline deterministic method for identification of inertia moment, mechanical losses, and electrical parameters for large induction machines, based on direct-on-line starting and natural slowdown tests, performed under no-load conditions. The static characteristic of absorbed power is used for the validation of results. Complete experimental results for a 6-kV four-pole 7500-kW machine are presented. The method brings significant cost savings for testing large induction machines.

Even slight differences in the movement of an electric-powered wheelchair may greatly affect riding comfort for wheelchair users. We focused on upper body tilt during acceleration and deceleration, a factor determining riding comfort and propose controlling tilt to control a user-friendly electric-powered wheelchair. We modeled the wheelchair and designed state variable feedback control with the upper body tilt angle and angular velocity of the upper body used as a state variable and an observer and an optimal regulator using Kalman filter for the presumption of the state variable. We assumed the state variable by the observer and state variable feedback control validated by the optimal regulator through computer simulation. We applied this control to the electric-powered wheelchair designed on a trial basis and indicated that upper body tilt could be suppressed by state variable feedback control.

Sports-related concussion (SRC) is one of the biggest health concerns today for youth athletes. Just a few short years ago an athlete would have returned to a game after sustaining a concussion even if symptomatic and applauded for their courage. The times have changed and SRC are finally recognized for being a legitimate brain injury requiring proper diagnosis and treatment. The chapter is designed for parents of children you play contact sports and want to be better informed about sports-related concussions so that they understand what it is, how it can be treated and how it interacts with return to school. This chapter will first define what a sports concussion, describe the mechanism involved in getting one and discuss the frequency at which it occurs with attention to different sports and gender. The chapter will then discuss signs and symptoms, immediate care, recovery, and treatment, long-term effects, and returns to play from concussions. Lastly issues of helmets, state laws, and prevention and education are discussed.

The travel time models of Automated Storage and Retrieval systems (AS/RS) machines under randomized storage proposed by Chang et al. (IIE Transactions, 27(1), 108–111, 1995), which consider the speed profiles in real-world applications, are extended in this paper. In the present study, travel time models are proposed that consider various travel speeds with known acceleration and deceleration rates. Compact forms of expected travel times under the class-based storage assignment and full-turnover-based storage assignment have been determined. The results show that both the proposed exponential travel time model and the adjusted exponential model perform satisfactorily and could be useful tools for designing an AS/RS in real-world applications.

Objectives: To ascertain the levels of trauma from an acceleration-deceleration event which would expose a person to brain trauma, and to suggest clinical guidelines to the evaluation of injury outcomes which would indicate significant brain trauma was a potential sequelae.Methods: The brain-injury literature that related to clinical, psychological, biomechanical, and imaging studies was reviewed and compared for correlation to injury outcomes.Results: The severity of cranio-cervical tissue damage is clearly correlated to the degree of acceleration-deceleration trauma exposure. The size of a brain lesion is in a direct correlation to the duration and depth of unconsciousness, and the duration of post-traumatic amnesia. The acceleration-deceleration mechanism of injury would expose the prefrontal, frontal, or temporal cortex to diffuse axonal injury. These brain regions are crucial for complex attentional functioning. Indicators of trauma severity [loss of consciousness] are correlated to both clinical [co...

Blunt force trauma to the stationary head is generally associated with cortical-subcortical injuries located at the site of impact (i.e., coup contusions). We present 2 cases of cerebral contusion injury secondary to falling tree limbs hitting the head, illustrating an exception to this observation. In each case, the most prominent lesions were white matter hemorrhagic contusions similar to those associated with acceleration-deceleration types of injuries characterizing falls or motor vehicle accidents (i.e., contrecoup contusions). The proposed pathogenesis for these observed lesions is a forceful impact resulting in the acceleration of the head and brain of a magnitude comparable with that in a motor vehicle accident or a fall. Language: en

Slip-ratio-based controllers are incompetent for precise longitudinal tire force tracking due to non-parametric model uncertainties. The tracking performance further deteriorates whenever the tire is simultaneously accelerating/decelerating and turning. In this paper, we propose an observer-based direct longitudinal tire force control scheme which guarantees achievement of the desired longitudinal tire force robustly with respect to tire model uncertainties, variations in road conditions, and simultaneous lateral tire motions. Convergence of the force estimation/tracking errors is analyzed rigorously by the Lyapunov method. Simulations demonstrate the satisfactory performance on both tire force estimation and tracking.

This paper presents a new methodology for controlling a vehicular powertrain system such as an automatic transmission. The driver's acceleration/deceleration intentions are critical factors in controlling systems such as the automatic transmission or the engine. Fuzzy inductive knowledge and vehicle mechanical models are proposed here as tools for inferring the driver's intentions. By using this knowledge, the driver's intentions can be inferred from driving characteristics. The road grade resistance is needed to determine both the driver's intentions and a suitable vehicle control strategy. Grade resistance is estimated using a mechanical model. A comparison is made with a conventional control system to show the performance improvements obtained with the proposed control methodology. The results verify the effectiveness of factoring the driver's intentions into powertrain control systems.

Although most of the literature on locomotion energetics and biomechanics is about constant-speed experiments, humans and animals tend to move at variable speeds in their daily life. This study addresses the following questions: 1) how much extra metabolic energy is associated with traveling a unit distance by adopting acceleration/deceleration cycles in walking and running, with respect to constant speed, and 2) how can biomechanics explain those metabolic findings. Ten males and ten females walked and ran at fluctuating speeds (5 ± 0, ± 1, ± 1.5, ± 2, ± 2.5 km/h for treadmill walking, 11 ± 0, ± 1, ± 2, ± 3, ± 4 km/h for treadmill and field running) in cycles lasting 6 s. Field experiments, consisting of subjects following a laser spot projected from a computer-controlled astronomic telescope, were necessary to check the noninertial bias of the oscillating-speed treadmill. Metabolic cost of transport was found to be almost constant at all speed oscillations for running and up to ±2 km/h for walking, with no remarkable differences between laboratory and field results. The substantial constancy of the metabolic cost is not explained by the predicted cost of pure acceleration/deceleration. As for walking, results from speed-oscillation running suggest that the inherent within-stride, elastic energy-free accelerations/decelerations when moving at constant speed work as a mechanical buffer for among-stride speed fluctuations, with no extra metabolic cost. Also, a recent theory about the analogy between sprint (level) running and constant-speed running on gradients, together with the mechanical determinants of gradient locomotion, helps to interpret the present findings.