The 1981 NASA/ASEE Summer Faculty Fellowship Program: Research reports

Research reports related to spacecraft industry technological advances, requirements, and applications were considered. Some of the topic areas addressed were: (1) Fabrication, evaluation, and use of high performance composites and ceramics, (2) antenna designs, (3) electronics and microcomputer applications and mathematical modeling and programming techniques, (4) design, fabrication, and failure detection methods for structural materials, components, and total systems, and (5) chemical studies of bindary organic mixtures and polymer synthesis. Space environment parameters were also discussed

Advances in Low-Cost Manufacturing and Folding of Solar Sail Membranes

Solar sail membranes must have a high area-to-mass ratio and high solid volume fraction when stowed. In order to meet mission requirements, current solar sail projects, such as NASAs Near Earth Asteroid Scout, require metallized sail membranes with thicknesses on the order of 2-3 m. These very thin membranes do not retain creases like thicker membranes, solar panels, or paper models. For Cubesat-class spacecraft, volume, rather than mass, is often the driving requirement for deployable structural elements. These two factors make it both difficult and highly desirable to characterize the practical differences between solar sail membrane packaging methods with laboratory demonstrations. This paper presents lessons gathered from lab work with solar sail membranes at a 10-meter scale

TRUNK AND UPPER EXTREMITY KINEMATICS OF THE OFFSIDE FOREHAND POLO SWING IN PROFESSIONAL POLO ATHLETES

The purpose of this study was to examine trunk (flexion, lateral flexion, rotation) and upper extremity (shoulder horizontal abduction, elevation, and elbow flexion) kinematics of the offside forehand polo swing between professional male and female polo athletes. Kinematic data were collected while participants performed the offside forehand polo swing on a stationary wooden horse. The polo swing was analyzed at three events: take away (TA), top of back swing (TOB) and ball contact (BC). Results revealed significant differences in trunk and upper extremity kinematics between the male and female professional polo athlete. Further investigation into these mechanical differences, along with the influence of live play and performance variables are necessitated to understand mechanics for the most powerful swin

The Effect of Single-Leg Stance on Dancer and Control Group Static Balance

International Journal of Exercise Science 9(2): 110-120, 2016. The purpose of this study was to compare kinetic differences of static balance between female dancers (D) with at least seven years of dance experience and female non-dancers (ND) who were typical college students. Participants were tested in single-leg stance. Both the dominant leg (DL) and non-dominant leg (NDL) were tested with the participants shod (S) and barefoot (BF). Kinetic variables (vertical, medio-lateral [ML], antero-posterior [AP] maximum ground reaction forces (GRF), and center of pressure (COP) ML and AP) were measured by a Bertec force platform at 1000 Hz with participants S and BF. Each subject’s stance was measured over 3 x 30-second intervals. No significant differences (p≥0.05) existed between groups for height, body mass, or age. Significant differences existed between groups for balance time, AP GRF in both BF and S conditions for both DL and NDL, and ML GRF in BF NDL and S DL and NDL conditions. D and ND in BF and S conditions with DL and NDL static stance demonstrate different AP and ML GRF when balancing over a 30-second time interval. Data may suggest that ND are more prone to lose their balance. Further investigation is warranted to understand whether individuals in the rehabilitative field and athletic populations can use dance therapy for injury prevention and rehabilitation

ESTUDO LONGITUDINAL DE FATORES QUE AFETAM O RISCO DE FRATURA POR ESTRESSE EM DUAS POPULAÇÕES DE COLEGIAIS DO SEXO FEMININO

Objetivos: As fraturas por estresse causam significante morbidade em mulheres. Diferenças no nível de atividades, valores hormonais e densidade mineral óssea (BMD) afetam diferentemente as taxas de fraturas por estresse. Os autores hipotetizaram que mulheres de um Colégio militar terão maior nível de atividade do que mulheres em colégios com um ambiente mais flexível, que correlacionará com mudanças nos valores hormonais, menor (BMD) e mais fraturas por estresse. Método: Nesse estudo prospectivo comparativo, 63 mulheres de duas Instituições (The Citadel: The Military College Of South Carolina And The College Of Cherleston) relataram detalhadamente suas atividades, dieta e lesões através de um questionário e tiveram sua BMB e os valores hormonais séricos medidos num intervalo de 06 meses, por um período de 2 anos; 38 sujeitos completaram o estudo. A análise estatística examinou diferenças e mudanças ao longo do tempo entre as duas amostras.Resultados: Uma fratura por estresse ocorreu em cada Instituição. As mulheres do Citadel tiveram maiores níveis de atividade, que as mulheres do College of Charleston no longo do estudo. As mulheres do Citadel tiveram menor nível de hormônio folículo estimulante, maior 17 Beta-Estradiol aos 24 meses e maior BMD na extremidade proximal femoral aos 18 meses da investigação (p< 0,05). Conclusões: Os valores séricos hormonais podem ser um indicador mais sensível de resposta ao nível da atividade física que o BMD dentro da amostra e duração deste estudo. Outros estudos são necessários para definir esta complexa interrelação. LONGITUDINAL STUDY OF FACTORS AFFECTING STRESS FRACTURE RISK IN TWO DISTINCT COLLEGE FEMALE POPULATIONS Abstract Objectives: Stress fractures cause significant morbidity in females. Differences in activity levels, hormone values, and bone mineral density (BMD) affect different rates of stress fracture. The authors hypothesized that females at a military college will have greater activity levels than females in a flexible college environment, which will correlate with greater changes in hormone values, lower BMD, and more stress fractures. Methods: In this prospective comparative study 63 females from two institutions (The Citadel: The Military College of South Carolina and the College of Charleston) self-reported on a detailed activity, diet, and injury questionnaire and had BMD and serum hormone values measured at 6- month intervals for a two year period; 38 completed the study. Statistical analysis was designed to examine differences and changes over time between the two samples. Results: One stress fracture occurred in each institution. Citadel females had higher activity levels than females at the College of Charleston throughout the study. Citadel females had lower follicle stimulating hormone levels at 24 months, greater 17 beta-estradiol at 24 months, and greater proximal femoral BMD at eighteen months (

Providing a Safe Harbor for Those Who Play by the Rules: The Case for a Strong Regulatory Compliance Defense

On September 25, 2003, a fire broke out at the National Health Care (NHC) nursing home facility in Nashville, Tennessee, causing sixteen deaths and a number of injuries from smoke inhalation. Thirty-two victims subsequently filed suit against the nursing home, alleging that NHC was negligent for failing to install sprinklers in its facility. This claim was made notwithstanding the fact that applicable federal, state, and local safety regulations did not require the installation of sprinklers in this particular type of building, and notwithstanding that the NHC facility had been inspected by state fire inspectors just months before the fire and was found to be in compliance with all requirements of the fire code. NHC eventually settled these lawsuits in order to avoid the uncertainty and expense of further litigation. The NHC case illustrates how good-faith compliance with applicable safety regulations provides businesses with almost no protection against potentially devastating tort liability. The problem is with the legal rule that governs compliance with government regulations. In effect, most courts treat a defendant\u27s compliance with governmental regulations as evidence of due care, but allow the jury to find that a defendant was negligent, notwithstanding his or her compliance with legislative or administrative regulations. We shall refer to this as the traditional approach to regulatory compliance. The traditional approach originated in Grand Trunk Railway Co. of Canada v. Ives, decided by the United States Supreme Court in the late nineteenth century. Later, § 288C of the Second Restatement of Torts endorsed this version of the rule, declaring that compliance with safety regulations was not conclusive evidence that a defendant exercised due care. The American Law Institute is currently in the process of drafting the Third Restatement of Torts, and the revised version of the regulatory compliance defense is substantially similar to that of the Second Restatement. In our view, there are many problems with the traditional approach. First, legislatures and administrative agencies have more expertise than lay juries when it comes to determining efficient levels of safety, but the traditional approach allows lay juries to second guess them. Second, under our constitutional system, legislative bodies and administrative agencies, not courts, are responsible for making resource allocation and other policy decisions. Therefore, courts should accept the trade-offs that are often embodied in safety regulations instead of allowing plaintiffs to use the litigation process to substitute their own policy choices for those of legislative bodies and administrative agencies. Third, the traditional approach wrongly assumes that government safety regulations merely set minimum standards, while, in reality, modem regulations typically reflect state-of-the-art standards. Thus, by adding jury-created safety standards on top of existing regulatory requirements, the traditional approach to regulatory compliance adds to the cost of doing business without achieving significant safety gains. Fourth, the traditional approach to regulatory compliance undermines the principle of uniform application of regulatory standards. Because jury verdicts are seldom consistent, business entities are often subjected to nonuniform safety standards. Finally, the traditional approach deters useful economic activity by imposing potentially crushing tort liability upon those who have complied in good faith with regulatory standards. Part II of this Article examines the traditional approach to the regulatory compliance defense, beginning with the Supreme Court\u27s opinion in Grand Trunk Railway Co. of Canada v. Ives, and proceeding to the Restatement (Second) § 288C and the Restatement (Third) of Torts: Liability for Physical Harm § 16. In Part III, we discuss a number of cases that explicitly recognize a strong regulatory compliance defense, as well as cases that achieve a similar objective by expressly or impliedly applying the Second Restatement\u27s § 16, comment (a) exception. Part IV reviews some of the arguments that support a stronger regulatory compliance defense. These include: (1) the institutional competence argument, (2) the separation of powers argument, (3) the regulatory efficiency argument, (4) the nonuniform standards argument, and (5) the overdeterrence argument. In Part V, we focus on nursing home regulation to -see what impact a stronger regulatory compliance defense would have on this socially useful industry. Finally, in Part VI, we set forth a proposed alternative to the current version of Restatement (Third) of Torts: Liability for Physical Harm § 16

Water Quality Impacts of Natural Riparian Grasses Part 1: Empirical Studies

Studies were conducted on the effectiveness of natural riparian grass buffer strips in removing sediment and ag chemicals from surface runoff. No till and conventional tillage erosion plots served as the sediment and chemical source area. Runoff from the plots was directed onto 15, 30, and 45 foot filter strips where the inflow and outflow concentrations and sediment size distributions. Trapping percentages for sediment and ag chemicals typically ranged near or above 90%. An evaluation was made of the distribution of trapped chemicals among infiltrated mass and mass stored in the surface layer and on plant surfaces. The analysis showed that most of the chemicals were trapped by infiltration onto the soil matrix

Volatile Decision Dynamics: Experiments, Stochastic Description, Intermittency Control, and Traffic Optimization

The coordinated and efficient distribution of limited resources by individual decisions is a fundamental, unsolved problem. When individuals compete for road capacities, time, space, money, goods, etc., they normally make decisions based on aggregate rather than complete information, such as TV news or stock market indices. In related experiments, we have observed a volatile decision dynamics and far-from-optimal payoff distributions. We have also identified ways of information presentation that can considerably improve the overall performance of the system. In order to determine optimal strategies of decision guidance by means of user-specific recommendations, a stochastic behavioural description is developed. These strategies manage to increase the adaptibility to changing conditions and to reduce the deviation from the time-dependent user equilibrium, thereby enhancing the average and individual payoffs. Hence, our guidance strategies can increase the performance of all users by reducing overreaction and stabilizing the decision dynamics. These results are highly significant for predicting decision behaviour, for reaching optimal behavioural distributions by decision support systems, and for information service providers. One of the promising fields of application is traffic optimization.Comment: For related work see http://www.helbing.or