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Psychophysical Load During The Multistage Marathon Des Sables: A Case Study, Leonidas G. Ioannou, Lydia Tsoutsoubi, Georgios I. Tsianos, Andreas D. Flouris

Journal of Human Performance in Extreme Environments

Introduction: This study investigated the impact of the multistage ultra-marathon event ‘‘Marathon des Sables’’ (MdS) performed in the Sahara Desert on the psychophysical capacity of an athlete. Methods: We collected and analyzed environmental, physiological, and behavioral data from a 39-year-old athlete who participated in the MdS. Specifically, we collected environmental temperature (T_env), upper inguinal skin temperature (T_sk), heart rate, and running speed data. Also, we recorded blood glucose and lactate, thermal comfort, total body water, perceived exertion, and cognitive function at the start, middle, and the end of each race stage. Results: We found significant detrimental …

Using An Approach-Avoidance Framework To Understand The Relationship Between Non-Lethal Weapons And Performance, Andrew J. Mojica, Christopher P. Bartak, Joseph N. Mitchell, Alan Ashworth

Journal of Human Performance in Extreme Environments

It is proposed that performance degradation from exposure to non-lethal technology is mediated by impulsive and reflective approachavoidance motivation. An approach-avoidance motivational framework was used to specify a four-stage information processing model that predicts performance degradation. The first stage is Evaluation: it processes physiological, sensory, perceptual, and cognitive information. The second stage is Comparison: it processes the content of the Evaluation into avoidance and approach motivational indices. The third stage is Probability: it processes information from previous stages into a probability of choosing to continue or abandon goal-directed behavior. Finally, the fourth stage is Performance: it processes performance accuracy on …

A Methodology For Observing The Deformation Of Rubber Studs When Stepping On A Stone, Robin Compeyron, Jürgen Mitternacht, Veit Senner, Bahador Keshvari, Valentin Wohlgut

International Sports Engineering Association – Engineering of Sport

No abstract provided.

The Effect Of Bending And Torsional Stiffness On The Edge Grip Of An Alpine Ski, Jonas Truong, Philippe Gosselin, Alexis Lussier-Desbiens

International Sports Engineering Association – Engineering of Sport

No abstract provided.

Early Life Benefits Of Hybrid Sports Turf, Paul Fleming, Lewis Darwin, Steph Forrester

International Sports Engineering Association – Engineering of Sport

No abstract provided.

The Permeability And Performance Of Competition Swimsuits, Hannah Deboer

International Sports Engineering Association – Engineering of Sport

No abstract provided.

Partisan Genealogies: Radical Visual (And Political) Practices. An Introduction, Paula Barreiro López

Artl@s Bulletin

This special issue has been conceived in the framework of the project Ré.Part. - Résistance(s) Partisane(s): Culture visuelle, imaginaires collectifs et mémoire révolutionnaire (Université Grenoble Alpes, ANR-15-IDEX-02) and the research project MoDe(s) – Decentralized Modernities: Art, Politics and Counterculture in the Transatlantic Axis during the Cold War (Universidad de Barcelona, HAR2017-82755-P).
We are very thankful for the support of the Jean Monnet Excellence Centre IMAGO (École normale supérieure - Université Paris Sciences Lettres, co-funded by the Erasmus + Program of the European Union) and of the Laboratoire de Recherches Historiques Rhône Alpes.
Many thanks to the editorial team of Artl@s …

Influence Of The Refrigerant Maldistribution In The Performance Of Brazed Plate Heat Exchangers Working With Propane, Emilio Navarro-Peris, Lucas Alvarez, Paloma Albaladejo, Lena Schnabel, Jose M Corberan

International Refrigeration and Air Conditioning Conference

Brazed plate heat exchangers (BPHE) are used widely in heating and cooling systems, mainly for liquid-to-liquid heat transfer but also for two-phase-applications like evaporation and condensation. Using them as evaporator or condenser in a heat pump the proper performance of them strongly influences the energy efficiency of the cycle and the required amount of refrigerant. One of the most common factors affecting the performance of BPHE is the not uniform distribution of the refrigerant. This problem is especially important in the evaporator as the refrigerant enters in it in two phase flow and usually the distribution of liquid and vapor …

Study On The Performance Of Co2 Two-Stage Rotary Compressor In Freezing And Cold Storage Conditions, Yusheng Hu, Huijun Wei, Jia Xu, Liping Ren, Peng Zou

International Compressor Engineering Conference

This paper describes a new type CO2 two-stage rotary compressor for cold storage and freezing of food. A two-stage compression form with an upper cylinder (first-stage) and a lower cylinder (second-stage), unique oil road structures and technical parameters have been used in the rotary compressor to increase the performance. The results indicating that the optimized CO2 two-stage rotary compressor has a significant performance advantage, which the coefficient of performance (COP) increases by 4.4% ~ 6.7%.

Selection Of Twin Screw Compressor Economizer Port Location To Optimize Unit Efficiency, Tasha Williams, Matthew Cambio

International Compressor Engineering Conference

Twin screw compressors are widely used in many applications. The performance limits of screw compressors are continuously being pushed to meet increased demand for energy efficiency. Several design adjustments can be made to the compressor to create a more efficient unit, such as the proper design of an economizer. The economizer is a port where refrigerant vapor is (re-)injected. General compressor effects of using an economizer are increase in compressor power, increase in discharge mass flow, and reduction of isentropic efficiency. However, the unit experiences an increase in refrigeration capacity and efficiency. The use of economizers for screw compressors is …

The Making Of A Caribbean Avant-Garde: Postmodernism As Post-Nationalism, Therese Kaspersen Hadchity

Comparative Cultural Studies

Focusing on the Anglophone Caribbean, The Making of a Caribbean Avant-Garde describes the rise and gradual consolidation of the visual arts avant-garde, which came to local and international attention in the 1990s. The book is centered on the critical and aesthetic strategies employed by this avant-garde to repudiate the previous generation’s commitment to modernism and anti-colonialism. In three sections, it highlights the many converging factors, which have pushed this avant-garde to the forefront of the region’s contemporary scene, and places it all in the context of growing dissatisfaction with the post-colonial state and its cultural policies.

This generational transition has …

Higher Muscle Tissue Oxygenation When Exposed To Hypobaric Hypoxia Than Normobaric Hypoxia, Christina N. Angeli, Robert J. Shute, Dustin R. Slivka

Journal of Human Performance in Extreme Environments

There has been recent debate on the potential difference in physiological response between exposure to simulated altitude (normobaric hypoxia) and terrestrial altitude (hypobaric hypoxia). Purpose: To determine the difference in the physiological response to normobaric and hypobaric hypoxia during exercise. Methods: Eight recreationally active subjects (27 ± 5 y old, 73.1 ± 7.4 kg body weight, 170.6 ± 6.7 cm height, and 19.3 ± 9.2 % body fat) completed incremental cycling exercise to volitional fatigue in three separate environments: normobaric normoxia (NN; 350 m), normobaric hypoxia (NH; simulated 3094 m), and hypobaric hypoxia (HH; 3094 m). Heart rate, blood oxygen …

Mimicry: A Short Play, Diana M. Pho

Journal of Southeast Asian American Education and Advancement

This short play is inspired by the author’s lived experience as a queer Vietnamese-American woman in academia and in US society. This theatrical piece, centered around two young women meeting for the first time after several years, reflects upon the mutable divergence of shared memory, while also exploring intersectional feminist theory and the Vietnamese-American community. This is also a critique of US-based stereotypes about young Asian-American women, and how social prejudices and microaggressions can result in internalized anti-Asian misogyny. Like the range of identities and life experiences that characters Laurel and Mattie have, the Asian diasporic experience in the United …

Safety–Performance Management In Extreme Sports? A Situated Analysis In Spearfishing Activity, Aude Villemain, Willy Buchmann

Journal of Human Performance in Extreme Environments

The aim of this research is to understand safety–performance articulation in spearfishing through the study of the global, specific, and temporal organization of an elite free diver’s activity. Three kinds of data were collected: diary reports, ten elicitation interviews on spearfishing, and two self-confrontation interviews on successful and failed apneas. The results indicated (1) the spearfisher’s global organization during the spearfishing set, (2) the alternation of intentions during apnea and periods of stabilization, (3) harmony with the environment, and (4) the strategy of keeping pace with the fish. The article will discuss the specific competence development needed to manage the …

Link Slab Details And Materials, Ghadir Haikal, Julio A. Ramirez, Mohammad R. Jahanshahi, Sandra Villamizar, Osama Abdelaleim

JTRP Technical Reports

This report contains the findings of a synthesis study on the use of link slabs to eliminate intermediate joints in bridges of Indiana. The study was conducted under the sponsorship of the Joint Transportation Research Program. The motivation for the study was to investigate this promising technique to mitigate the damage associated with expansion joints that has long been recognized as a persistent and costly issue negatively impacting the bridge service life.

The report summarizes the background information and motivation for the study. It also provides a description of the report organization. The results of an extensive literature review of …

Social Brokerage, Psychology, And Innovation In Intra-Organizational Networks, Hongzhi Chen

Open Access Dissertations

As an important organizational phenomenon, brokerage is common in any group of three or more. A recent meta-analysis shows that brokerage is one of the most influential network properties to individual innovativeness (Baer, Evans, Oldham, & Boasso, 2015). This dissertation investigates the impacts of social brokerage on the micro-foundation of corporate innovation, i.e., generating new projects and getting new things done. In addressing the social psychological foundations of brokerage (Tasselli, Kilduff, & Menges, 2015), this dissertation investigates the influential contexts around the broker and revisits the “human agency” issue in brokerage phenomena in the setting of corporate innovation.

Chapter One …

Habitual Heat Exposure And Acclimatization Associated With Athletic Performance In The Multistage Marathon Des Sables, Leonidas G. Ioannou, Lydia Tsoutsoubi, Lars Nybo, Georgios I. Tsianos, Andreas D. Flouris

Journal of Human Performance in Extreme Environments

Introduction

The aim of this study was to investigate the impact of heat acclimatization on athletic performance during the 7-day Marathon des Sables (MdS) which takes place in the Sahara Desert.

Methods

Anonymous data for nationality and average running speed (km/h) of all runners who ran the MdS during the period 2000–2015 were collected from the official website of the race and other related websites. Average maximum temperature for each runner’s country during the month preceding the MdS was collected from www.weatherbase.com. Athletes were divided into two Torigin groups as follows: 25 to 15°C (i.e., cold countries) and 15 to …

Simulation Of 1d Flow Coupled With 3d Multi-Body Dynamics Model Of A Double-Acting Swashplate Compressor, Gautham Ramchandran, Kanwal Bhatia, Rodrigo Aihara

International Compressor Engineering Conference

This paper describes an integrated 1D/3D modeling approach for a multi-cylinder double-acting automotive A/C compressor using a multi-physics CAE system simulation software, GT-SUITE. This tool is used to build a 1D flow model of a compressor using the original CAD, along with a 3D multi-body dynamics model to study overall compressor performance. Various flow and mechanical-related built-in libraries, supported with pertinent physics, are utilized to study fluid flow and related forces on the pistons, shaft and the swashplate. There exists an easy approach in the software to schedule the suction and compression cycles in the cylinders. A full 3D modeling …

Non-Intrusive Performance Assessment Method For Heat Pumps: Experimental Validation And Robustness Evaluation Facing Faults, Derek Noël, Cédric Teuillieres, Philippe Riviere, Odile Cauret, Dominique Marchio

International Refrigeration and Air Conditioning Conference

Thanks to their high theoretical efficiency, residential heat pumps (HP) are a promising technology when attempting to reduce the energy consumption of heating in dwellings. Evaluation of their real performances on-field is thus crucial to promote their development and deployment. However, measuring accurately real heating capacity of air-to-air HP is not easy, since measuring air enthalpy and mass flow rate is challenging. A previously developed non-intrusive internal method based on the compressor energy balance has been improved. It can calculate the coefficient of performance (COP) of different HP types, including air-to-air, on field, thanks to real-time measurements, without interfering with …

Novel Vapor Compression Cycles With High Energy Efficiency Using Natural Refrigerants For Three Kinds Of Appliances, Jianhua Wu, Jiachen Li

International Refrigeration and Air Conditioning Conference

Natural refrigerants are eco-friendly substitutes for HCFCs and HFCs in vapor compression cycles, such as refrigeration or heat pump cycles. In this paper, three appliance systems are analyzed based on refrigerants characteristics for performance improvement, and novel and practical cycles are proposed and briefly analyzed. Dual-evaporator (DE) cycle for refrigerator can reduce the irreversible thermodynamic loss in one-stage cycle. Rotary compressors which have advantages in efficiency and dynamic balance capability are highly suitable to DE cycles. The improvement of theoretical refrigeration coefficient for DE cycle is up to 24.4% comparing with conventional one-stage cycle under refrigerator condition. Vapor injection heat …

A Novel Structure Of Rolling Piston Type Rotary Compressor, Myeong Su Shin, Sang-Kyung Na, G.M. Choi

International Compressor Engineering Conference

This paper presents a new design of rolling piston type rotary compressor and the analysis of the performance of the novel compressor is conducted. The concept of the novel compressor is to utilize the interior space of the roller as inner working volume. The vane is connected and fixed to the outer cylinder and the inner cylinder, and the split bush is located between the roller and the vane to help revolution of the roller. Therefore, the novel compressor has two working volumes. One is outer volume trapped within the outer cylinder, the vane, and the roller and the other …

Eldoret, Kenya: Creating A Music Experience For Street Youth, Michael J. Peters, Ethan C. Wahl

Purdue Journal of Service-Learning and International Engagement

The authors of this essay completed an advance pharmacy practice experience in adult medicine at Moi Teaching and Referral Hospital in Eldoret, Kenya. In this article, they describe their efforts to establish a music experience program with the Tumaini Innovation Center for street children while on rotation in Eldoret, Kenya. Through the foundation of the program, they hope to provide an outlet for the children to express themselves while filling a gap in fine arts training provided by the center.

Coping With The Subterranean Environment: A Thematic Content Analysis Of The Narratives Of Cave Explorers, Raymond R. Macneil, Jelena Brcic

Journal of Human Performance in Extreme Environments

In addition to various physical obstacles, the cave environment presents numerous psychological stressors that challenge human explorers. Sources of psychological stress include logistic issues (e.g., limitations to access, communication, and the availability of equipment), a lack of normal sensory stimuli, isolation and confinement, high performance demands, and social conflict associated with team coordination and requirements for cooperation. Thus, the success and safety of caving expeditions depend on the ability of explorers to effectively cope with highly stressful conditions and task demands. This was the first study to investigate coping within the context of caving and cave exploration. Utilizing scoring criteria …

Energy Balance During A Self-Sufficient, Multistage Ultramarathon, Paul A. Hough, James Earle

Journal of Human Performance in Extreme Environments

Endurance athletes are recommended to maintain energy balance and ensure adequate energy availability (EA) so that endurance performance is not compromised. Purpose: Describe and evaluate the energy balance of an athlete competing in a self-sufficient, multistage ultramarathon (MSU). Methods: A male endurance athlete (age 35 years; height 183.0 cm; body mass 78.4 kg; VO_2max 66 ml/kg/min) volunteered to take part in this observational case study prior to competing in the Marathon des Sables (MdS) 2016. The subject self-reported energy intake (EI) by reviewing his dietary plan following each stage. Basal metabolic rate (BMR) was estimated prior to the MdS …

Kisses Sweeter Than Wine. Öyvind Fahlström And Billy Klüver: The Swedish Neo-Avant-Garde In New York, Per Bäckström

Artl@s Bulletin

The Swedish artist Öyvind Fahlström moved to New York in 1961, where he meet the Swedish engineer Billy Klüver, and became part of the international neo-avant-garde movement. Fahlström’s performance, New York 1966, part of Klüver’s performance series 9 Evenings, is my point of departure for an analysis of the role of migration for the neo-avant-gardes in the 1960s. As intermediaries, Fahlström and Klüver brought new ideas both to New York and Stockholm, thus challenging the established view that American art was exported to the periphery. In reality, the New York art scene grew out of ideas and experiences arriving …

Curating Automatic Vehicle Location Data To Compare The Performance Of Outlier Filtering Methods, Jijo K. Mathew, Christopher M. Day, Howell Li, Darcy M. Bullock

JTRP Affiliated Reports

Agencies use a variety of technologies and data providers to obtain travel time information. The best quality data can be obtained from second-by-second tracking of vehicles, but that data presents many challenges in terms of privacy, storage requirements and analysis. More frequently agencies collect or purchase segment travel time based upon some type of matching of vehicles between two spatially distributed points. Typical methods for that data collection involve license plate re-identification, Bluetooth, Wi-Fi, or some type of rolling DSRC identifier. One of the challenges in each of these sampling techniques is to employ filtering techniques to remove outliers associated …

Experimental Investigation On The Influence Of Refrigerant Charge On The Performance Of Trans-Critical Co2 Water-Water Heat Pump, Ze Zhang, Rong Xue, Shuangtao Chen, Shijie Song, Yu Hou

International Refrigeration and Air Conditioning Conference

Natural refrigerant CO2 is widely used in refrigeration and heat pump systems. It is of great significance for reductions of ozone depletion and global warming. The efficiency of heat pump system is affected by many factors. The amount of refrigerant charge in the heat pump is a primary parameter that influences the energy efficiency. Undercharge or overcharge of refrigerant degrade its performance and deteriorate system reliability. Therefore, heat pump should be charged with an optimum amount of refrigerant to achieve high performance. However, it is difficult to calculate the optimum charge accurately because of the various components and operating parameters. …

Linear Compressor Suction Valve Optimization, Rinaldo Puff, Dietmar E. B. Lilie, Marcelo Knies, Marcos G. D. Bortoli

International Compressor Engineering Conference

Design of hermetic compressors for household refrigeration follows a common sequence that considers an initial concept, normally based on existing families. Those are then upgraded with new features, aiming improvements in efficiency, sound quality or even cost reduction. Common compressors have a cylinder head that carries discharge and suction valve. In a new and compact designs for linear compressor suction valve is placed on the top of the piston, requiring new shapes in order to make it possible to satisfy, gas flow, fatigue and dynamics requirements. This article aims to present the use of optimization procedure used to develop the …

Cfd Analysis And Experiment Study Of The Rotary Two-Stage Inverter Compressor With Vapor Injection, Liying Deng, Shebing Liang, Jia Xu, Yusheng Hu

International Compressor Engineering Conference

The offset angle of the upper and lower part of the crankshaft will affect the resistance of inspiration of high stage cylinder in the rotary two-stage inverter compressor with vapor injection, and then affect the performance. this paper presents the performance of the rotary two-stage inverter compressor with vapor injection in the bias angle of the crankshaft is calculated and compared with the experimental. The simulation results are in agreement with the experimental results. Under the operation of close vapor injection and open vapor injection, the performance of compressor can be improved 1% and 3% separately by optimize the bial …

A Comprehensive Evaluation Of Regression Uncertainty And The Effect Of Sample Size On The Ahri-540 Method Of Compressor Performance Representation, Vikrant Aute, Cara Martin

International Compressor Engineering Conference

AHRI-540 is the current standard defining the methods for representing compressor performance data. While this standard is widely used across the industry, multiple factors contribute to inaccuracies in data representation including measurement uncertainty, regression uncertainty, compressor to compressor variation, and operation outside of the normal operating envelope (extrapolation). In addition, the number and location of points in the operating envelop also affects the accuracy of the resulting 10-coefficient polynomial. The measurement uncertainty is well known and can be factored into the data reduction. However, the measurement uncertainty is generally not propagated into the regression uncertainty and hence the overall uncertainty …