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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

Konstrukcinių mazgų analizė ir pritaikymas kuprinės gamyboje / Structural sub-assemblies analysis and customizing a backpack production

Juškaitė, Sandra 29 June 2012 (has links)
Bakalauro darbo tikslas – išanalizuoti kuprinės konstrukcinius mazgus ir pritaikyti juos jos gamyboje. Darbo pradžioje aprašoma baigiamojo darbo techninė užduotis. Pateikiama konstrukcinių mazgų analizė, kurioje aprašomi pagrindiniai kuprinės konstrukciniai mazgai, tokie kaip: užtrauktuko įsiuvimas, uždėtinių kišenių prisiuvimas, petnešų susiuvimas. Antrame skyriuje atliekama mados krypties analizė, kurioje aprašomi kuprinių tipai, madingi jų akcentai, medžiagos, spalvos. Aprašomas projektuojamas kuprinės modelis, pateikiamas iš priekio ir nugaros spalvinis eskizas. Parenkama tinkama medžiaga ir furnitūra, nubraižoma bazinė konstrukcija. Panaudojant bazinės konstrukcijos brėžinį, sudaromi gaminio lekalai. Programa COMTENSE sudaromos lekalų išklotinės, nustatomos medžiagų sąnaudos. Apibendrinama kokybės kontrolė gaminio projektavimo etapuose. Trečiame skyriuje pateikiamos universaliųjų, specialiųjų įrengimų, pusautomačių charakteristikos, naudojamų mažosios mechanizacijos priemonių charakteristikos, bei gaminio apdorojimo siūlių charakteristikos. Sudaroma gaminio apdorojimo technologija ir darbo padala, apskaičiuojami jos pagrindiniai rodikliai. Atliekamas siuvimo srauto planavimas. Darbo pabaigoje parašomos išvados, pateikiamas literatūros sąrašas. Prieduose pateikiami du kuprinės analogai su aprašymais, bazinė konstrukcija, gaminio lekalai, technologiniai pjūviai, gaminio surinkimo technologinė schema, siuvimo srauto planas. / The aim of the Bachelor's research work is to analyse the structural sub-assemblies of the backpack and to customize them in its production. The technical task is described in the beginning of the research work. It is provided an analysis of the structural sub-assemblies which describes the basic backpack structural sub-assemblies such as: the zipper sewing, flashed sewing pockets, seaming of the straps. In the second chapter, there is done the analysis of the fashion trend, which describes the types of backpacks, their fashionable accents, the materials and colours. Also, there is given the model of the designed backpack and the description of the front and back colour sketch. The appropriate material and supply are selected, and the basic plot structure is drawn. Using the basic design drawing of the product, the templets are formed. According to the programme COMTENSE, the evolvent of the product templets are made and the outlay of the material is proposed. The quality control of product design stages is generalized. In the third section there are provided the universal and special equipment, the characteristics of semi-automatic machines which are used in small mechanization means, the characteristics of the product and processing characteristics of the joints. The processing technology and the work interval are formed, and the calculation of the main indicators is done. The planning of the sewing flow is carried out. In the end of the research work there are written the... [to full text]
12

Load Carrying Assistance Device: Pogo Suit

January 2014 (has links)
abstract: Wearable robots including exoskeletons, powered prosthetics, and powered orthotics must add energy to the person at an appropriate time to enhance, augment, or supplement human performance. Adding energy while not being in sync with the user can dramatically hurt performance making it necessary to have correct timing with the user. Many human tasks such as walking, running, and hopping are repeating or cyclic tasks and a robot can add energy in sync with the repeating pattern for assistance. A method has been developed to add energy at the appropriate time to the repeating limit cycle based on a phase oscillator. The phase oscillator eliminates time from the forcing function which is based purely on the motion of the user. This approach has been simulated, implemented and tested in a robotic backpack which facilitates carrying heavy loads. The device oscillates the load of the backpack, based on the motion of the user, in order to add energy at the correct time and thus reduce the amount of energy required for walking with a heavy load. Models were developed in Working Model 2-D, a dynamics simulation software, in conjunction with MATLAB to verify theory and test control methods. The control system developed is robust and has successfully operated on a range of different users, each with their own different and distinct gait. The results of experimental testing validated the corresponding models. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2014
13

Estudo da relação das alterações posturais em adolescentes com o uso de mochilas escolares

ALEIXO, Joseph Daniel Alves 31 July 2015 (has links)
Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-04-01T17:55:47Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação JOSEPH DANIEL ALVES ALEIXO pdf.pdf: 2006598 bytes, checksum: 012dc1b1e71ec22af595af908e910f56 (MD5) / Made available in DSpace on 2016-04-01T17:55:47Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação JOSEPH DANIEL ALVES ALEIXO pdf.pdf: 2006598 bytes, checksum: 012dc1b1e71ec22af595af908e910f56 (MD5) Previous issue date: 2015-07-31 / A ergonomia é o estudo do relacionamento entre o homem e o seu trabalho, estudando as interações das pessoas com a tecnologia, organização e ambiente. Em diferentes situações, é importante verificar se a execução de determinada tarefa está sendo realizada pelo indivíduo, respeitando sua capacidade física e mental. Alterações na postura são ocasionadas pelo carregamento de cargas por longos percursos e esta questão tem despertado a atenção de vários estudiosos na área. Em crianças, variações posturais são comumente encontradas no período do crescimento e desenvolvimento. A partir do exposto, este trabalho teve como objetivo verificar a relação entre o carregamento de mochilas escolares e a presença de alterações posturais em adolescentes. Este trabalho trata-se de um estudo transversal. Foi realizado na cidade de Vitória de Santo Antão, com adolescentes estudantes de uma escola pública na faixa etária de 10 a 14 anos de ambos os sexos. Os adolescentes foram selecionados aleatoriamente, com o consentimento de seus responsáveis. Os instrumentos utilizados foram um formulário de pesquisa contendo dados pessoais, peso, altura, dados sobre a mochila escolar, um instrumento de avaliação postural e o inventário da dor de Becker. Os dados foram tabulados e passaram por análises estatísticas. Houve associação estatisticamente significativa entre o uso de alças ajustáveis com a faixa etária uso de costas almofadadas e sexo; uso de duas alças apoiadas nos ombros e sexo; tempo de trajeto de deslocamento com a presença de alterações posturais; e uso de alças ajustáveis com a presença de alterações posturais. Este panorama reflete na necessidade de intervenções baseadas em processos educativos, tanto para os adolescentes, pais e professores para que esse quadro se reverta, diminuindo, assim, os agravos à saúde. Apesar das limitações apresentadas pelo estudo, novas pesquisas ainda devem ser realizadas. / Ergonomics is the study of the relationship between man and his work, studying the interactions of people with technology, organization and environment. In different situations, it is important to check whether the execution of certain task is being performed by the individual, respecting their physical and mental capacity. Alterations in posture are caused by loading cargoes for long distances and this issue has attracted the attention of several scholars in the area. In children, postural changes are commonly found in the growth and development period. From the foregoing, this study aimed to investigate the relationship between the backpacks carrying and the presence of postural alterations in adolescents. This work it is a cross-sectional study. It was held in the city of Vitória de Santo Antão, with teenage students in a public school in the age group of 10-14 years old of both sexes. The adolescents were randomly selected, with the consent of their parents. The instruments used were a survey form containing personal data, weight, height, data on school backpack, postural assessment tool and the Becker inventory of pain. Data were tabulated and underwent statistical analysis. There was a statistically significant association between the use of adjustable straps to age; use of padded back and sex; use of two handles resting on shoulders and sex; displacement path of time with the presence of postural alterations; and the use of adjustable straps with the presence of postural alterations. This outlook reflects the need for interventions based on educational processes, both for teens, parents and teachers, so that this situation be reversed, thus, reducing the health problems. Despite the limitations presented by the study, more research must still be performed.
14

Backpack Energy Harvester with Human Walking Model

Yuan, Yue 05 June 2017 (has links)
The objective of this thesis is to design, analyze, and fabricate an innovative backpack energy harvester for human walking. To model human walking with backpack energy harvester, a simple dual-mass model has been developed and studied first. Dual-mass model for three types of distinct harvesters were investigated, pure damping, traditional rack pinion energy harvester and our MMR based energy harvester. A comparison in the output power and human comfort between the three types of harvesters is discussed. However, the dual-mass model could not effectively represent human walking in real situation with sinusoidal input, like M shaped Ground Reaction Force (GRF), vertical Center of Mass (COM) motion, etc. Thus, a bipedal walking model has been proposed to simulate human walking with backpack harvester. Experiments were conducted to compare power output and efficiency of MMR based backpack energy harvester with traditional rack pinion backpack energy harvester, and verify conclusions from the bipedal walking model that the proposed backpack energy harvester using mechanical motion rectifier (MMR) mechanism has larger power output than traditional backpack energy harvester at different walking speed. In human treadmill test, subjects were asked to wear the backpack frame which embedded with harvesters walking on a treadmill. Two walking speed, 3mph and 3.5mph, and four resistor values has been tested. The test results showed that the MMR based backpack energy harvester generated more power regardless of resistor values and walking speed. Up to 4.84W average power and instant power of 12.8W could be obtained while the subject walking on the treadmill at 3.5mph speed with MMR based backpack energy harvester. / Master of Science / The objective of this thesis is to design, analyze, and fabricate an innovative backpack energy harvester for human walking. To model human walking with backpack energy harvester, a simple dual-mass model has been developed and studied first. Dual-mass model for three types of distinct harvesters were investigated, pure damping, traditional rack pinion energy harvester and our Mechanical Motion Rectifier based energy harvester. A comparison in the output power and human comfort between the three types of harvesters is discussed. In addition, a bipedal walking model has been proposed to better simulate human walking with backpack harvester than simple dual mass model. Experiments were conducted to compare power output and efficiency of MMR based backpack energy harvester with traditional rack pinion backpack energy harvester, and verify conclusions from the bipedal walking model that the proposed backpack energy harvester using mechanical motion rectifier mechanism has larger power output than traditional backpack energy harvester at different walking speed.. Up to 4.84W average power and instant power of 12.8W could be obtained while the subject walking on the treadmill at 3.5mph speed with MMR based backpack energy harvester. This research could make significant benefit for human live, from student walking while charging their electronics to soldiers during long time mission. This suspended load backpack could reduce load while generating electricity.
15

Backpacks HARK’AY

Coronado Medina, Consuelo Esther, Freyre Ramírez, Miguel Ángel, Gamarra Trujillo, Juan Carlos Sergio, Vásquez Peña, Mariela Lisbeth, Zelayaran Garcia, Dayana Stefany 09 December 2020 (has links)
Actualmente todo el mundo vive una emergencia sanitaria como consecuencia del Covid-19 y en Perú debido a esta enfermedad muestra un cambio de hábitos para movilizarse hacia sus centros de trabajo, ir al supermercado, ir de paseo, etc. Por ello, el presente plan de negocio analiza la viabilidad del proyecto empresarial HARK’AY que consiste en brindar una salida para aquellas personas que muestran un gran interés en movilizarse a través de bicicletas. Este proyecto surge de la experiencia personal de nuestro entorno familiar al oír las constantes quejas y poca comodidad que tenían al transportarse en sus bicicletas. Por este motivo, diseñamos un accesorio para bicicletas que alivie las frustraciones de los ciclistas de Lima metropolitana al transportarse por la ciudad. Por otro lado, con el avance de la tecnología queremos ofrecer un valor agregado a nuestro producto, paneles solares, que estarán adaptados a las backpack para que mediante la energía solar puedan cargar todo tipo de artículos electrónicos tales como laptops, celulares, baterías externas, etc. que será de gran oportunidad para aquellas personas que quieren adquirir más que un producto que cubra sus necesidades, también les permitirá contribuir con el medioambiente a través de la tecnología. Para poner en marcha nuestra empresa, contaremos con 5 trabajadores y la zona escogida como centro de operaciones estará en el distrito del Callao. Además, se tiene como objetivo recuperar la inversión inicial de S/. 42,455.00 soles, el primer año y lograr expandir nuestra propuesta de negocio hacia provincias en dos años. / Currently, everyone is experiencing a health emergency as a result of Covid-19 and in Peru due to this disease shows a change in habits to move to their work centers, go to the supermarket, go for a walk, etc. For this reason, this business plan analyzes the viability of the HARK'AY business project, which consists of providing an outlet for those people who show a great interest in mobilizing by bicycle. This project arises from the personal experience of our family environment when hearing the constant complaints and little comfort that they had when transporting their bicycles. For this reason, we designed a bicycle accessory that alleviates the frustrations of the cyclists of metropolitan Lima when traveling around the city. On the other hand, with the advancement of technology we want to offer an added value to our produc, solar panels, which will be adapted to a backpack so that through solar energy they can charge all kinds of electronic items such as laptops, cell phones, batteries external, etc. which will be a great opportunity for those who want to acquire more than a product that meets their needs, it will also allow them to contribute to the environment through technology. To start our company, we will have 5 workers and the area was chosen as the center of operations will be in the Callao district. In addition, the objective is to recover the initial investment of S /. 42,455.00 soles, the first year and to expand our business proposal to the provinces in two years. / Trabajo de investigación
16

Postural Compensations and Subjective Complaints Due to Backpack Loads and Wear Time in Schoolchildren Aged 8 to 11

Kistner, Frances E 25 July 2011 (has links)
Backpacks are used by more than 90% of schoolchildren worldwide and over 40 million students in the United States on a regular basis. The carriage of loaded backpacks is associated with kinematic and physiological changes, as well as complaints of neck and back pain. Since a history of backpain in childhood is the strongest predictor of having musculoskeletal discomfort and back pain as an adult, development of back pain due to backpack use is of prognostic concern. The purpose of this dissertation was to examine the effects of backpack weights (up to 20% body weight (BW)) on children’s posture, subjective complaints of pain and perceived exertion, and walking endurance. A secondary goal was to examine the data to identify and recommend a weight limit for backpacks carried by elementary school children based on the results. In Chapter 2, we performed a preliminary study designed to examine the effects of loaded backpacks on forward head posture in school children. The results of this study found that forward head posture increased with both backpack weight and condition. The greatest differences were noted at the 15% and 20%BW backpack loads with initial loading, but after 6 minutes of walking the forward head posture was similar for all backpack loads. In Chapter 3, we conducted a study to evaluate multiple postural angles and the subjective complaints of pain and perceived exertion/fatigue in children to determine the effects of both the weight and time spent carrying loaded backpacks up to 20%BW. Subjects showed significant changes in all measures including the Six Minute Walk Test (6MWT), OMNI Walk/Run Scale of perceived exertion/fatigue and subjective complaints of pain, as well as the postural angles of Craniovertebral Angle, Forward Trunk Lean, and Pelvic Tilt. Subjects demonstrated immediate and significant changes in forward head posture, forward trunk lean, and pelvic tilt while wearing backpacks weighing 10%, 15% and 20%BW, but the 10%BW backpack resulted in the least amount of change. This study also found that these postural angles changed additionally after walking 6 minutes while carrying the loaded backpacks. Subjects also demonstrated decreased 6MWT distances and increased reports of perceived exertion and pain after carrying backpacks weighing 10%, 15% and 20%BW. In Chapter 4, we discussed the clinical implications of this research. It was determined that backpack loads weighing 10%, 15% and 20%BW of a child’s body weight result in immediate changes in posture, which continue to increase after walking six minutes with the loaded backpack. The backpack loads significantly impacted the children’s walking endurance as well as their reports of perceived exertion/fatigue and regional pain. This study found that of the loads tested, the 10%BW resulted in the least amount of change in all outcome measures. However, the 10%BW load was not innocuous, as it still created significant changes in posture and subjective complaints. Backpack weight limit guidelines need to be written to protect children from carrying backpacks weighing more than 10% body weight.
17

Design of a backpack container with cooking and eating tools.

Jiménez Sánchez, Carlos, Gallego Sánchez, Irene January 2012 (has links)
The aim of this project was to develop a product in cooperation with Primus Company in Stockholm. It consisted of designing a container with the items needed when cooking and eating outdoors, in order to help the users eat and cook in a proper way while practicing activities such as camping or hiking.   Considering the specifications posed by Primus, research was done. One of the main issues to start this research was to carry out a market analysis in order to know all the products similar to the one that was going to be developed. Then, an analysis of the company and the main competitors of it was done in order to develop a product with Primus style and to get ideas for the product. In addition, a questionnaire study directed to potential users was carried out. In this way, it was possible to get to know things such as which items people usually carry in their backpack for cooking and eating outdoors and which ones they considered essential. This helped with making a choice of what the product should contain.   Once all the information collected from the research and from the study of the specifications was prioritized, the concept development phase started. For reaching an outcome, many aspects such as the items that the container should include, the shape of the container and the best material for the product were discussed.   Primus TetraCube is a product that suits all the requirements established at the beginning. In this way, Primus TetraCube is a product that can be carried in an 80 litres backpack and where the user can store all the necessary items for four people who want to eat and cook outdoors. It has also been designed taking into consideration all the details, resulting in a product that follows the aesthetics of Primus with soft shapes and colours such as red, black and grey. Everything combined make Primus TetraCube a comfortable product which helps the user feel at home in terms of convenience and comfort.
18

Tecnologia de aplicação de herbicidas no controle de plantas daninhas / Herbicide application technology on weed control

Campos, Henrique Borges Neves [UNESP] 19 April 2017 (has links)
Submitted by Henrique Borges Neves Campos (hcampos_ea@hotmail.com) on 2018-08-19T09:48:51Z No. of bitstreams: 1 TESE HBN CAMPOS 2018.pdf: 5571147 bytes, checksum: 1c555ec338396b960800948162d4d9b8 (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-08-20T17:37:29Z (GMT) No. of bitstreams: 1 campos_hbn_dr_jabo.pdf: 5571147 bytes, checksum: 1c555ec338396b960800948162d4d9b8 (MD5) / Made available in DSpace on 2018-08-20T17:37:29Z (GMT). No. of bitstreams: 1 campos_hbn_dr_jabo.pdf: 5571147 bytes, checksum: 1c555ec338396b960800948162d4d9b8 (MD5) Previous issue date: 2017-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Esta Tese nasceu de duas grandes oportunidades, avaliar o espectro de gotas pelo método de difração laser em túnel de vento de alta velocidade na Universidade de Nebraska-Lincoln (EUA) e contribuir com o desenvolvimento comercial do produto Herbiciclo Duo® da fabricante de pulverizadores Herbicat. As hipóteses que: (1) os adjuvantes agrícolas a base de polímero em mistura com herbicidas podem mitigar a deriva de gotas em aplicações aéreas e (2) o sistema de aplicação localizada WeedSeeker® é eficaz, preciso e economicamente viável foram usadas como base deste estudo. Foram avaliados cinco adjuvantes polímeros em mistura em tanque com os herbicidas 2,4-D e picloram quanto à deriva sob condições de pulverização aérea. Já, o sistema de aplicação localizada WeedSeeker® foi avaliado embarcado em quadriciclos para controle de plantas daninhas na entrelinha da cana-de-açúcar em função do tamanho de plantas, velocidade de aplicação, condições de irradiância e doses do herbicida glyphosate. Espera-se com este estudo apresentar estratégias para difundir práticas mais sustentáveis de intervenção fitossanitária em curto, médio e longo prazo. / This thesis was created from two great opportunities, to evaluate the droplet spectra by using high speed wind tunnel laser diffraction method at the University of Nebraska-Lincoln (USA) and to contribute to the commercial development of the Herbiciclo Duo® product, produced by Herbicat sprayer manufacturer. The hypothesis that: (1) polymer adjuvants tank mixture with herbicides can mitigate spray drift under aerial applications and (2) the WeedSeeker® spot spray system is effective, accurate, and economically feasible were used as the basis for this study. The effect of five polymer adjuvants tank mixture with 2,4-D and picloram herbicides were evaluated due spray drift under aerial application conditions. The WeedSeeker® spot spray system was evaluated on quadicycle for weed control on sugarcane interrow due to plant size, speed track, irradiance conditions and glyphosate herbicide doses. It is hoped that this study presents strategies to disseminate more sustainable practices of phytosanitary intervention in the short, medium and long term.
19

Improve Improper Load Distribution with Backpack

Chen, Qinqing, Su, Xiao January 2018 (has links)
This article focuses on the distribution of backpack pressure on human body. We have noticed two interesting situations: whether the length of different backpack shoulder straps will change the pressure distribution of the backpack on the human body and whether different positions of the backpack load will change the pressure distribution of the backpack on the human body. To find the answer, we designed a backpack pressure detection system to collect data and use engineering software to analyse the data.We got the range that best fits the human body and the healthiest backpack: when the distance from the top of the backpack to the shoulder is about 1/5 of the length of the shoulder and the weight of the backpack is at the bottom of the backpack. At this time, the force of the three parts of the human body (shoulders, back) is the most uniform and relatively minimal. If the user wants to minimize the pressure on the shoulder, the shoulder strap of the backpack should be as short as possible. If the user only wants the pressure on the back to be minimal, the weight in the backpack is closer to the back, which is better for the back.
20

Utveckling av testmetod för och utvärdering av Butterfly Bridge : Ett experimentellt examensarbete på uppdrag av Klättermuse

Sellström, Marcus, Forsberg, Clara January 2022 (has links)
Ryggsäckar används vid mängder av aktiviteter och har många fördelar jämfört med andra väskor, särskilt när det kommer till att bära tungt. Emellertid blir dåligt utformade ryggsäckar med bristande hänsyn till ergonomiska faktorer obekväma och kan i värsta fall orsaka skador. Studier har visat att belastningen på axlar är den främst begränsande faktorn vid ryggsäcksbärande. Klättermusen har försökt lösa detta problem med innovationen Butterfly Bridge som är tänkt att fördela lasten över axeln på ett mer skonsamt sätt. Projektet genomfördes i syfte att bredda kunskapen kring ryggsäckars påverkan på kroppen samt bidra med information om Butterfly Bridges effekt till uppdragsgivaren. Mer specifikt var målet med projektet att utveckla lämplig metod för att mäta effekten och utvärdera huruvida Butterfly Bridge fungerar som beskrivet och har en mätbar effekt på tryckfördelning mellan ryggsäck och axel. Den inledande litteraturstudien visade på ett antal tillgängliga metoder för att mäta och bedöma en ryggsäcks påverkan på kroppen. För att utvärdera Butterfly Bridges effekt valdes en kvantitativ metod med experimentella tester på testdocka. Trycket mellan axelrem och dockan mättes med taktila trycksensorer från Tekscan. Mätningar gjordes med och utan Butterfly Bridge för två ryggsäckar från Klättermusen, Grip 60L och Ymer 65L. Resultaten visade inte på någon skillnad mellan att använda Butterfly Bridge eller inte. Tryckbilder från mätningarna visade inga synliga skillnader i tryckfördelning och det kan utifrån mätningarna i denna studie inte bevisas att Butterfly Bridge har någon effekt på tryckfördelningen. Slutsatsen är att Tekscan F-Scan kan användas för att mäta skillnader i tryck mellan olika ryggsäckar men metoden är på intet sätt felfri. Fler tester krävs för att bestämma Butterfly Bridges effekt. / <p>2022-07-01</p>

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