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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Measuring the causal effect of air temperature on violent crime

Söderdahl, Fabian, Hammarström, Karl January 2015 (has links)
This thesis aimed to apply the causal framework with potential outcomes to examine the causal effect of air temperature on reported violent crimes in Swedish municipalities. The Generalized Estimating Equations method was used on yearly, monthly and also July only data for the time period 2002-2014. One significant causal effect was established but the majority of the results pointed to there being no causal effect between air temperature and reported violent crimes.
12

Utah commercial motor vehicle weigh-in-motion data analysis and calibration methodology /

Seegmiller, Luke W., January 2006 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Civil and Environmental Engineering, 2006. / Includes bibliographical references (p. 125-129).
13

Development of a regression equation for estimating the weight of male black South African adults with paraplegia using anthropometric measurements

Snyman, Hildegard 12 1900 (has links)
Thesis (MNutr (Human Nutrition))--University of Stellenbosch, 2005. / Introduction: The objective of this study was to develop a regression equation to estimate weight of black male paraplegic South African subjects. Very few institutions in South Africa have wheel chair scales and very few paraplegic persons know what their weight is. People with spinal cord injury (SCI) are reported to have an increased risk to develop obesity and diseases of lifestyle. It is therefore important to monitor the nutritional status of these patients to prevent and treat the above diseases effectively. The aim was to develop an equation that incorporates variables or measurements that do not require a high level of skill and experience to be determined. The equipment needed for the determination of the measurements should also be easily accessible, for example a tape measure rather than a skin-fold caliper.
14

Effects of Hydration Changes on Bioelectrical Impedance in Endurance Trained Individuals

Saunders, Michael J., Blevins, Jennifer E., Broeder, Craig E. 18 June 1998 (has links)
Purpose: The purpose of this study was to determine how differences in hydration states and ion content of hydrating fluids affected bioelectrical impedance (BI) and hydrostatic weighing (HW) measurements. Methods: Fifteen athletic subjects aged 19-56 yr were recruited. Relative body fat (%), fat- weight (FW), and fat-free weight (FW) were assessed using BI and HW under normal conditions (N), hypohydration (HPO), rehydration (RHY), and superhydration (SHY) states. During the RHY and SHY trial periods, subjects were hydrated with either distilled water or an electrolyte solution (ELS). HPO and SHY levels were set at 3% of each person's normally hydrated body weight. Results: Comparison between the distilled water and the ELS trials indicated that hydration solution had no effect on BI or HW. Thus, the results presented are the trial means of both hydration solutions combined. Both BI and HW were shown to be highly test-retest reliable (r-values: 0.96 and 0.99, respectively). The effects of exercise induced HPO followed by RHY on body composition values indicated that HW was very stable across measurement periods while BI was not. From N to the HPO state, BI %BF declined from 14.4 ± 5.3% to 12.3 ± 5.3%, respectively. After RHY, BIA %BF increased to 15.5 ± 5.8%. Similar findings occurred when subjects were superhydrated (N-BI = 13.2 ± 5.3%; SHY-BI = 15.4 ± 5.6%). With a comparison of the intercepts and slopes of HW and BIA for the N and SHY states, it was clear hydration status significantly affected the intercepts (HW: 0.37 vs. BI: 1.85) and not the slopes (HW: 1.00 vs BI: 0.99). As a result, a majority of all fluid changes were interpreted as FW by BI. During HPO, 82% of the weight loss was considered FW while during RHY or SHY, 128% and 85% of the water weight regain/gain was considered FW. Conclusion: These results indicate that BI is not a valid technique in athletes, especially when wanting to determine body composition effects of training/detraining. This study indicates that even small fluid changes such as those that occur with endurance training may be interpreted incorrectly as changes in an athlete's body fat content.
15

Assessing Body Composition Before and After Resistance or Endurance Training

Broeder, Craig E., Burrhus, Keith A., Svanevik, Lars S., Volpe, Joseph, Wilmore, Jack H. 01 January 1997 (has links)
This study's purpose was to determine the validity of near-infrared interactance (NIR) and bioelectric impedance (BIA) in tracking changes in body composition over 12 wk of either a high intensity endurance (ET) or resistance (RT) training program in nondieting weight-stable untrained males. Prior to and following the control or training period, each subject completed a series of body composition analyses including hydrostatic weighing (HW) with a measurement of residual volume; anthropometric measurements including height, weight, skinfold, and girth; BIA measurement; and NIR measurements. Based on the HW results, there were no significant body composition changes in the control group. For the ET group, a significant decline in relative body fat resulted from a reduction in fat weight (FW) with no change in fat-free weight (FFW). In the RT group, both a significant decline in FW and an increase in FFW contributed to this group's decline in relative body fat. Tracking changes in relative body fat, FW, and FFW, skinfolds agreed reasonably well with HW in all groups while BIA and NIR did not always track body composition changes well. For example, SF and BIA were significantly correlated with the changes in FFW (HW = + 4.1%, SF = + 4.5%, BIA = + 3.1% NIR = - 0.7%) observed in the RT group compared to HW (SF: r-value = 0.45, SEE = 2.5; BIA; r = 0.33, SEE = 3.4) while the NIR measurements were nonsignificant (r = 0.09, SEE = 5.0). Interestingly, NIR underestimated the gain in FFW in the resistance trained group while BIA underestimated the changes in relative body fat, FW, and FFW in the endurance trained group. Based on these results, BIA aim NIR appear not to be appropriate measurement tools for tracking body composition changes in endurance and resistance training individuals respectively.
16

The Effect of Creatine Supplementation on Muscle Fuel Stores, Body Composition, and Exercise Performance During Energy Restriction

Rockwell, John A. 11 April 1998 (has links)
The purpose of this investigation was to determine the effects of a four day creatine load and simultaneous energy restriction on muscle creatine content, exercise performance, and body composition in 24 male recreational resistance trainers, age 18-26. Sixteen subjects were randomly divided into placebo (Pl, n=8) and creatine supplement (CrS, n=8) groups. Control (C, n=8) subjects of the same age were recruited separately g à d-1 to complete the performance and body composition tests while consuming their normal diet. The CrS group was administered 20 g à d-1 of creatine monohydrate (Cr) mixed with 5 g à d-1 of sucrose, while the Pl group was administered 25 of sucrose. Both CrS and Pl consumed a formula diet of 75.3 kJ (18 kcal) à kg-1 à d-1 for 4 d. Testing before and after energy restriction consisted of a repeated sprint cycle performance test (10 sprints of 6s, with 30s rest), hydrostatic weighing, and resting needle muscle biopsy. Testing revealed that subjects in CrS and Pl demonstrated significant decreases in body weight and % body fat (%BF) with no difference between groups. However, Pl demonstrated a significantly greater % loss in FFM (2.4 ± 0.25%) compared to CrS (1.4 ± 0.4%) (p<0.05). The muscle fuel stores of CrS and Pl responded significantly to the diet. Significant increases in muscle total Cr (p<0.01), free Cr (p<0.01), and CrP (p<0.05) of 16.5%, 16.8%, and 16% respectively were demonstrated by CrS over the energy restriction period, while Pl demonstrated significant decreases of 7.2% and 8.2% respectively in muscle total Cr (p<0.01) and free Cr (p<0.05). There were no significant differences between groups for performance during the cycle test, however, there were trends toward group by time interactions for performance enhancement in CrS relative to Pl, as total work (p=0.078) and work capacity (p=0.058) increased 3.8 ± 2.2% in CrS and decreased 0.5 ± 0.4% in Pl. It was concluded that short-term energy restriction resulted in decreased muscle Cr storage, and that Cr supplementation during energy restriction increased muscle Cr and CrP stores. Consumption of Cr allowed CrS to lose a significantly lower % FFM compared to Pl. Cr supplementation resulted in trends toward improved performance in CrS relative to Pl after energy restriction, but did not influence losses in body weight or %BF. / Master of Science
17

Operation and Calibration Procedures for a Small Four-component Strain Gage Balance

Rasponi, Gary Allen 01 January 1974 (has links) (PDF)
The Florida Technological University four-component strain-gage balance is an internally mounted, half-inch diameter balance capable of measuring four components of load: front and rear normal force, axial force, and rolling moment. Measurement of these components is accomplished by means of sixteen strain gages that are mounted on the balance and wired into four full bridge circuits. When the balance is subjected to a load, the strain gages, through a small resistance change, indicated the strain a balance element is undergoing. This report presents a description of the balance and its support equipment, and outlines specific calibration procedures necessary to their successful implementation. These calibration procedures take two forms: that of calibrating the readout equipment, and that of calibrating the balance itself. Also contained in this report is a method of reducing calibration data into a set of parameters applicable to the balance. To aid in the calibration of the balance, a calibration assembly was designed and built. Two calibration models were designed to facilitate the incremental loading of the balance and the interpretation of the readout data.
18

Modelagem e simulação de sistema de embalagem e pesagem de material particulado em pó. / Modeling and simulation of a packaging and weighing system of granulated powders.

Oliveira, Rafael Couto Rodrigues de 08 August 2014 (has links)
Esse trabalho é dedicado ao desenvolvimento de um simulador para sistema de pesagem e embalagem de produto em pó granulado. Tal simulador reproduz a variabilidade de peso dos cartuchos observados em um sistema de embalagem real. Para esse desenvolvimento foram aplicadas técnicas de Identificação de Sistemas para obter o modelo determinístico do processo e conceitos de Processos Estocásticos para reproduzir as perturbações. O simulador tem como objetivo a avaliação de propostas de melhorias nesse sistema de pesagem, visando reduzir o sobrepeso médio e a quantidade de cartuchos rejeitados por subpeso, denominados de scraps, diminuindo consequentemente as perdas monetárias do processo industrial de embalagem de produtos granulados, com grande potencial de reaplicação para outros tipos de produtos industrializados e sistemas de pesagem. O desempenho do simulador é muito bom, uma vez que as oscilações observadas nos pesos dos cartuchos, devido à variação de densidade, são bem reproduzidas. Portanto as principais contribuições desse trabalho são: 1) o uso de uma abordagem estatística e inovadora para modelar as perturbações, evitando o estudo profundo de suas causas, alcançando um modelo preciso, que simula resultados de sobrepeso e número de cartuchos rejeitados bem próximo da realidade; 2) identificação e quantificação de melhorias no sistema de pesagem e embalagem, sem a necessidade de altos investimentos, dando a opção de decisão de quais melhorias realmente serão implementadas; 3) sobrepeso e scrap normalmente estão entre as três principais perdas monetárias das indústrias que produzem produtos embalados por peso e esse simulador representa uma forma de redução significativa dessas perdas, trazendo uma grande vantagem competitiva em um mercado cada vez mais acirrado. / This work describes the development of a simulator for a packing and weighing system of granulated powder. This simulator reproduces the weight variability of observed cartons in a real packing system. In this development, System Identification techniques were used to obtain the deterministic part of the model and Stochastic Processes to reproduce disturbances. Its objective is to evaluate proposed improvements in the packing and weighing system, aiming at reducing the overweight average and the quantity of rejected cartons by underweight, denominated scraps, cutting down consequently the monetary losses of the granulated product packing process in the industry, with great reapplication potential to other kind of industry products and weighing systems. The simulator performance is very satisfactory, once the oscillations observed in the carton weights, due to powder density variability, are well reproduced. Hence, the main contributions of this work are: 1) use of a statistical and innovative approach to model the disturbances, avoiding a deep study of their causes, achieving a model that provided precise simulated overpacking and scrap results when compared to reality; 2) identification and quantification improvements of the weighing and packing system, with no large investment, giving the option of decision of which improvement will be actually implemented; 3) overweight and scrap are among the three main monetary losses in the industries that make products packed in weight and so this simulator of a packing and weighing system of granulated powder represents a way of reducing significantly these losses, bringing a big competitive advantage in a demanding market.
19

Posouzení metody stanovení průtoku jímáním kapaliny do odměrné nebo vážicí nádoby / Method analysis for flow measurement by collecting fluid into the volumetric or weighing vessel

Valdová, Klára January 2016 (has links)
This diploma thesis is concerned with assessment of two methods of gauging the flow rate used in the sphere of official measurements on profiles with an unrestricted water level. This is the method of collecting liquid into a volumetric vessel and the method of collecting liquid into a weighing vessel (pouch). The main purpose of this work was to specify uncertainties determined using method A and B for these two methods of gauging flow rate within the terms of addressing the Metrology Development Plan of the Czech Office for Standards, Metrology and Testing, because these uncertainties were previously determined using older methodology and using less accurate flow rate benchmarks. The entire work is based on extensive experimental measurement of the flow rate, using the assessed methods, executed at the Laboratory of Water Management Research in Brno. The method of collecting liquids into a volumetric vessel was assessed using four various vessel volumes - 9 l, 15 l, 30 l and 50 l. Relative uncertainties determined using method A and B in relation to flow rate are determined for each vessel in the experimental section of this work. Within the scope of this thesis, these uncertainties were also determined for the method of collection of liquid into weighing vessel (pouch), which was assessed for flow rates of from 0,5 l/s to 10,0 l/s.
20

Sunkiosios technikos masės nustatymo metodų analizė / Analysis of the Determining Methods of Heavy Vehicles

Pikšilingytė, Elita 13 June 2014 (has links)
Baigiamajame magistro darbe nagrinėjama dinaminio svėrimo įranga A1 Vilnius– Kaunas–Klaipėda kelyje. Išnagrinėtas statinis ir dinaminis svėrimo metodas, naudojama įranga, jos tikslumas ir efektyvumas. Analizuojama dinaminio svėrimo sistema, jos konstrukcija, veikimo principas. Tiriamas įrangos tikslumas. Atliekamas 2012 ir 2013 m. tyrimas pagal Klaipėdos transporto inspekcijos duomenis. Nustatoma, kurios klasės transporto priemonės padarė daugiausia pažeidimų. Nustatoma, kiek transporto priemonių viršijo leistiną apkrovą bei leistinus matmenis. Išnagrinėjus teorinius ir praktinius aspektus, pateikiamos baigiamojo darbo išvados ir pasiūlymai. Darbą sudaro 6 dalys: įvadas, literatūros apžvalga, tiriamoji dalis, eksperimentinis tyrimas, išvados ir siūlymai, literatūros sąrašas. Darbo apimtis – 63 p. teksto be priedų, 50 iliustr., 7 lent., 13 bibliografinių šaltinių. Atskirai pridedami darbo priedai. / The main objective of this master thesis is to analize dynamic weighing system in A1 Vilnius–Kaunas–Klaipėda road. There were analized static and dynamic weighing methods, used equipment, it‘s accuracy and efficiency. Dynamic weighing system ,it‘s construction, accuracy, working principle has been studied. According Klaipėda‘s transport inspection data, 2012 and 2013 years research has been made. Research shows which type of vehicles makes most violations. Determined how many vehicles exceeded permissible load and permissible dimensions. After theoretical and experimental analysis aspects, final conclusions and recommendations were suggested. Structure consists of 6 parts: introduction, literature overview, test part, experimental part, conclusions and suggestions, references. Thesis consist of: 63 p. text without appendixes, 50 pictures, 7 tables, 13 bibliographical entries. Appendixes included.

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