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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.
1

Säkrare lyft i materialförsörjningen på ABB Robotics : Tillämpning av NIOSH reviderade lyftekvation

Engström, Johan January 2019 (has links)
A modernization of the ABB Robotics production system has led to a large part of the manual handling being moved upstream in the logistics chain towards the logistics department. This study aims to identify and make recommendations to address the risks associated with manual lifting in the logistics department. To measure and analyze the lifts, the National Institute for Occupational Safety and Health's revised lifting equation has been used. The logistics department consists of the areas washing, goods reception and logistics center. In the wash, two articles were identified that require potentially strenuous manual handling. The root cause was considered to be the design of the pallet system. A new pallet system is recommended as a measure. The manual handling in goods reception did not meet the conditions set by the revised lifting equation and therefore no conclusion about the risks could be drawn. At the logistics center, three risk elements were identified; repackaging in light flow, replenishing the supermarket shelf and order picking from the supermarket shelf. In addition to specific recommendations for each risk element, a new material handling system consisting of vertical lifting modules is recommended. General conclusions that can be drawn from the study are that work-related stress injuries are a major and growing problem, which particularly affects industrial and logistics personnel. The problem identified at Robotics is believed to be relevant to many manufacturing industries facing the same challenges in terms of increased productivity requirements. Due to the constant pressure that either occurs internally or externally, there is a need for more efficient production processes. Repacking materials in standardized load carriers or kitting materials material before it is presented to the production are examples of ways to achieve higher efficiency in the production. In this way, manual handling in the production can be reduced and thus also the time required for such handling. When non-value adding activities in the production decrease from repacking or kitting, the load on the internal logistics function increase. This study has shown how that poor ergonomics in the internal logistics largely depends on the design of the work processes and material flows and not necessarily on available tools or regulations. Improving ergonomics should therefore be seen as a natural part of the development of internal logistics, the purpose of which is to create efficient flows. / En modernisering av ABB Robotics produktionssystem har lett till att en stor del av den manuella hanteringen har flyttats uppströms i logistikkedjan mot logistikavdelningen. Det här arbetet har syftat till att identifiera och ta fram rekommendationer för att åtgärda de risker som finns kopplade till manuella lyft på logistikavdelningen. För att mäta och analysera lyften användes National Institute for Occupational Safety and Health’s reviderade lyftekvation. Valet att använda den reviderade lyftekvationen motiverades av verktygets tillförlitlighet och möjligheten att genomföra ingående analyser av lyftens olika beståndsdelar. Genom att belysa vilken del av ett lyft som medför störst risk för skada kan de mest effektfulla åtgärderna prioriteras. Logistikavdelningen består av områdena tvätt, ankommande och logistikcenter. I tvätten identifierades två problemartiklar som kräver potentiellt riskfylld hantering av personalen. Rotorsaken bedömdes vara pallsystemets utformning och ett nytt pallsystem rekommenderas som åtgärd. Den manuella hanteringen på ankommande uppfyllde inte de förutsättningar som ställs av den reviderade lyftekvationen och någon slutsats om riskerna där kunde därför inte dras. På logistikcentret identifierades tre riskmoment; ompackning i lätta flödet, påfyllning av supermarket-hyllan och orderplock från supermarket-hyllan. Förutom punktinsatser för respektive riskmoment rekommenderas ett nytt materialhanteringssystem bestående av vertikala lyftmoduler. Generella slutsatser som kan dras från studien är att arbetsrelaterade belastningsskador är ett stort och växande problem som i synnerhet drabbar bland annat industri- och logistikpersonal. Problemet som identifierats på Robotics antas vara relevant för många tillverkande industrier som står inför samma utmaningar i form av ökade produktivitetskrav. På grund av de ständiga påtryckningar som antingen uppstår internt eller externt, finns det ett behov av mer effektiva produktionsprocesser. Att packa om eller kitta material ankommande material innan det presenteras till produktionen är en möjlig åtgärd för att uppnå högre effektivitet i produktionen. På så sätt kan den manuella hanteringen i produktionen reduceras och därmed också tiden som krävs för hanteringen. I samband med att belastningen minskar i produktionen till följd av ompackning eller kittning ökar belastningen på den interna logistikfunktionen. Det här arbetet har visat hur orsaken till bristande ergonomi i den interna logistiken till stor del grundar sig i arbetsprocessernas och flödenas utformning och inte nödvändigtvis på de verktyg eller föreskrifter som finns. Att arbeta med ergonomi bör därför ses som en naturlig del av utvecklingen av den interna logistiken vars syfte är att skapa effektiva flöden.
2

An investigation of carbon nanotube exposure assessment methods

Horne, Adrianne 01 May 2013 (has links)
Objectives: 1 To correlate carbon nanotube (CNT) concentrations measured by Method 5040 relative to particle count concentrations; 2 to correlate CNT concentrations measured by Method 5040 relative to black carbon concentrations measured with an aethalometer; 3 to compare elemental carbon (EC) concentrations measured by Method 5040 among various CNT types and purities. Methods: CNT samples were collected using 25 mm quartz fiber filters and analyzed for EC by Method 5040. An aethalometer was simultaneously used to measure black carbon concentrations. Samples sent for EC analysis included various CNT types (multi-walled, single-walled) and purities (high, low). Levels of EC concentration were subjected to a two-way analysis of variance having two levels of CNT type and two levels of purity. Results: No correlation was established between CNT count and EC concentration, but a correlation was found between CNT volumetric and total carbon (TC) concentration. A significant correlation between black carbon and TC concentration was found. Method 5040 was found to have a positive bias for TC, and the aethalometer was found to have a positive bias for black carbon. Lastly, this study found that CNT type had no effect on EC concentration, but purity did have a significant effect on EC concentration. Conclusions: Samples analyzed by Method 5040 were found to have 6 - 19% EC content, and thus surprisingly high amounts of organic carbon. It is reasoned that significant amounts of impurities were introduced to CNT samples while travelling through the experimental apparatus. When TC concentrations were plotted against black carbon concentrations a significant relationship was found and the bias of Method 5040 and the aethalometer cancelled out. Future research is needed to investigate the aethalometer as a surrogate for Method 5040. Until then, those conducting CNT exposure assessments should use a 25 mm cassette and increase the volume sampled to achieve a reporting limit lower than the NIOSH recommended CNT REL of 7 µg/m3.
3

MANIKIN - Möglichkeiten und Grenzen des Menschmodells

Heine, Andreas 04 June 2010 (has links) (PDF)
Das Menschmodell MANIKIN bietet dem Anwender neue Möglichkeiten in der Analyse des arbeitstechnischen Umfeldes in der bekannten Pro/ENGINEER Umgebung. Dazu kann auf eine anthropometrische Datenbank zurückgegriffen werden. Neben einfachen Analysen, wie Reichweite und Sichtfenster, steht auch ein umfangreiches Angebot an Ergonomie-Analysen zur Untersuchung von Arbeitsprozessen zur Verfügung. Diese basieren auf den bekannten Grundlagen wie RULA, SNOOK und NIOSH91. Weiterhin ist das Modell gut zur Animation von Menschen bzw. Mensch-Maschine-Interaktionen geeignet, wobei hier ein spezielles Wissen über den Aufbau und den Einsatz von Körpersperrbedingungen zuträglich ist.
4

Measurement of community and laboratory-generated airborne particulates using a new sampling method

Farina, Laura 01 June 2010 (has links)
This project resulted from an alleged dust problem affecting the residents in a Florida community. The residents claimed that there were elevated dust levels caused by a rock quarry adjacent to their homes. The purpose of this work was to assess total particulate, respirable particulate, and the coarse content of the sampled particles through traditional NIOSH methods, and using a new, real-time instrument known as the EPAM 5000. Data from the EPAM and NIOSH methods were compared to the EPA's particulate matter standards and the OSHA permissible exposure limits for total and respirable dust. Dust levels using the NIOSH methods were below the limit of detection. There were measurable dust levels in all three size fractions (PM10, PM[subscript 2.5], PM1) for the EPAM. Due to the undetectable levels of the NIOSH method sampling, further sampling in a laboratory environment was conducted in order to compare NIOSH methods with the EPAM 5000 method. The project continued into an aerosol chamber in the USF College of Public Health Breath Lab for further data collection in order to compare results using traditional NIOSH methods with the results obtained from the EPAM 5000. The chamber was associated with a dust generator that released a steady flow of fly ash particulate at a specific revolution per minute (rpm). Each run of data collection sampled approximately 1 m³ of air and persisted for six to seven hours. Four separate runs were conducted, each at a different generation rate of fly ash. There were measurable dust levels using the NIOSH total dust and NIOSH respirable dust methods. There were also measurable dust levels in all three size fractions (PM10, PM[subscript 2.5], PM1) for the EPAM. The results of all methods were compared. The PM[subscript 2.5] and PM1 sampling heads of the EPAM 5000 were compared to the NIOSH respirable dust sampling results. The PM10 sampling head of the EPAM was compared to the NIOSH total dust sampling results. NIOSH 0500 concentration results were within 10% of the EPAM PM10 concentration.
5

Noise Exposure in Medical Helicopter Flights

Hay, Melissa Constance 01 January 2012 (has links)
The purpose of this project was to evaluate noise exposures of helicopter pilots, nurses and paramedics at a hospital by collecting area and personal samples, determining noise levels inside the helmet, and evaluating the current selection of personal protective equipment (PPE). Measurements gathered during personal sampling were statistically analyzed and calculated using OSHA 1910.95 App A to determine dose, reference duration and the Time-Weighted Average (TWA). Using a mannequin head, with the noise dosimeters in the ears, tests were performed on the headset inside the helmets to determine the sound pressure levels generated from the radio communications at different volume levels. According to our results, the crew is not exposed to hearing levels above the OSHA permissible exposure limit (PEL), because their flight times are usually only 20-30 minutes and the dose not above 22% of the OSHA limit. If the total flight times were 6.5 hours or more, the crew could be above the OSHA PEL. Testing the helmet speakers resulted in a recommendation that the setting not be set above the 6 o'clock position so that the crew would not be exposed to sound pressure levels about 80 dBA
6

Filtration Efficiency of Surgical Masks

Sanchez, Erin 18 February 2010 (has links)
Surgical masks are intended to be used to prevent transmission of disease from a health care worker to a patient. Often times, they are relied upon by health care workers for their own protection. In light of recent developments regarding preparation for health care worker response to global infectious diseases such as H1N1 Influenza, health care workers may experience a false sense of security when wearing surgical masks. The goal of this study was to evaluate the filtration efficiency of a double strap tie-on surgical mask. The manufacturer asserts a >95% efficiency with a 0.1 um challenge aerosol under FDA testing procedures. The NIOSH Title 42 CFR Part 84 certification criteria call for testing at a rate of 85 lpm representing a human moderate to heavy work load breathing rate. Three sizes of monodispersed aerosols (polystyrene latex beads: 0.5 um, 1.0 um, 2.0 um) were used. The specific aims were to measure the collection efficiencies of this mask for the various particle sizes. Two tests were performed. In the first, masks were affixed to a dummy head and the edges of the mask were not sealed. In the second, the edges of the masks were sealed to the head using silicone sealant, so all penetration was through the filtering material of the mask. Differences in upstream and downstream particle concentrations were measured. Thus, penetration by leakage around the mask and through the filtering material was measured. The experimental set up involved passing the aerosol from the nebulizer through a diffusion dryer and Kr-85 charge equilibrator ensuring a dry charge neutralized aerosol cloud for detection by a LASAIR particle counter. The analysis revealed that the filtration efficiency for 0.5 um particles ranged from 3% to 43% for the unsealed masks and 42% to 51% for the sealed. For 1.0 um particles, the efficiency was 58% to 75% for unsealed and 71% to 84% for sealed masks. For 2.0 um, the efficiency was 58% to 79% for unsealed masks and 69% to 85% for the sealed masks. The data were statistically significant and indicated that surgical masks were associated with very low filtration efficiency. This suggests that they may be inadequate against airborne viruses and bacteria.
7

Perceived and Actual Personal Listening Device Volumes in College-Age Students: Is Education Enough?

Marchiondo, Kendrah T. 04 May 2012 (has links)
No description available.
8

A REAPPRAISAL OF NIOSH LIFTING EQUATION: A WORKER-BASED ASSESSMENT

JIANG, ZHENLEI January 2001 (has links)
No description available.
9

Product Evaluation and Process Improvement Guidelines for the Personal Protective Equipment Manufacturers based on Human Factors, NIOSH Guidelines and System Safety Principles

Deshmukh, Atul Ramesh 13 March 2007 (has links)
To analyze the system development, manufacturing practices and system evaluation procedures of representative PPES manufacturers, two companies (i.e., one "small", referred to here as "simple manufacturer (SM)", and one "large", referred here as "complex manufacturer (CM)" — in terms of workforce, market presence, and capital) that develop first responder PPES, which voluntarily agreed to participate in the research were chosen. The complex PPES is an Air-Pak, a self contained breathing apparatus (SCBA) used by first responders for artificial breathing in life-threatening scenarios and the simple PPES is the Fire-Eye device, a thermal sensor that attaches to the visor of the firefighter in order to convey the visual warning of the ambient thermal environment. In order to differentiate the two distinct methodological approaches, the dissertation has been split into two different parts. The first methodology is a "case study" type of empirical investigation which follows a triangulation approach utilizing surveys, structured interviews, process and system observations, and examination of archival records. The second type of methodology is an experimental empirical research one, which involves laboratory-scale and full-scale real-life fire scenarios to conduct product evaluation. The research goals of the case study research were to identify the problems faced by the manufacturers of PPES and to formulate guidelines with regards to manufacturing, compliance, design and development processes, etc., for the PPES manufacturers. The investigation sought answer to the following key questions: a) How do PPES manufacturers currently approach the systems design and development process and what best practices in manufacturing and quality control have they adopted? b) What human factors and ergonomic measures are adopted by these companies while designing their products and what human testing is conducted by companies? c)What safety measures are considered by the safety designer while designing the product? The recommendations also include modifications to the product design process taking into account the market trends in the product design processes, involvement of ergonomics and safety aspects. The research goals for the experimental part of this dissertation were to identify appropriate evaluation methods and conduct the PPES evaluation in simulated fire environments. The Fire-Eye device primarily functions in hot environments and warns the firefighters of the ambient temperature. Therefore, the laboratory-scale evaluation was conducted using test methods such as the Static Oven, Fire Equipment Evaluator, and Radiant Panel, methods which represent controlled environment test conditions. The Fire-Eye device was also evaluated in realistic fire environment created in an ISO burn room by conducting several tests using different types of fuels such as Heptane, Natural Gas, and Living-room set-up (i.e., furniture as fuel). The Fire-Eye device was tested for repeatability and reproducibility of its performance in both of the experimental settings. Statistical data analysis was conducted to determine any differences in performance of the Fire-Eye device among each laboratory-scale methods as well as to compare the performance of the device between laboratory-scale and full-scale fire environments in identical heat locations. The results suggest that a dual approach (laboratory-scale and full-scale fire environment) for evaluating the performance of PPES is more effective than is testing the device in either one of the methods. / Ph. D.
10

Automating a labour performance measurement and risk assessment: an evaluation of methods for a computer vision based system

Van Blommestein, Donald Lloyd 04 1900 (has links)
Thesis (MScEng) Stellenbosch University, 2014 / ENGLISH ABSTRACT: This thesis brings together productivity and risk assessments through innovative design, development and evaluation of a unique system for retrieving and analysing data. In the past, although the link between them is well-documented, these assessments have largely been dealt with as separate antagonist entities. A broad evaluation of the existing traditional and technological support systems has been conducted to identify suitable methodologies along with a common technological platform for automation. The methodologies selected for the productivity and risk assessments were; work sampling and the revised NIOSH lifting equation respectively. The automation of these procedures is facilitated through computer vision and the use of a range imaging Kinect™ camera. The standalone C++ application integrates two tracking approaches to extract real-time positional data on the worker and the work-piece. The OpenNI and OpenCV libraries are used to perform skeletal tracking and image recognition respectively. The skeletal tracker returns positional data on specific joints of the worker, while the image recognition component, a SURF implementation, is used to identify and track a specific work-piece within the capture frame. These tracking techniques are computationally expensive. In order to enable real time execution of the program, Nvidia’s CUDA toolkit and threading building blocks have been applied to reduce the processing time. The performance measurement system is a continuous sampling derivative of work sampling. The speed of the worker’s hand movements and proximity to the work-piece are used to classify the worker in one of four possible states; busy, static, idle, or out of frame. In addition to the worker based performance measures, data relating to work-pieces are also calculated. These include the number of work-pieces processed by a specific worker, along with the average and variations in the processing times. The risk assessment is an automated approach of the revised NIOSH lifting equation. The system calculates when a worker makes and/or breaks contact with the work-piece and uses the joint locations from the skeletal tracker to calculate the variables used in the determination of the multipliers and ultimately the recommended weight limit and lifting index. The final calculation indicates whether the worker is at risk of developing a musculoskeletal disorder. Additionally the information provided on each of the multipliers highlights which elements of the lifting task contribute the most to the risk. The user-interface design ensures that the system is easy to use. The interface also displays the results of the study enabling analysts to assess worker performance at any time in real time. The automated system therefore enables analysts to respond rapidly to rectify problems. The system also reduces the complexity of performing studies and it eliminates human errors. The time and costs required to perform the studies are reduced and the system can become a permanent fixture on factory floors. The development of the automated system opens the door for further development of the system to ultimately enable more detailed assessments of productivity and risk. / AFRIKAANSE OPSOMMING: Produktiwiteit en risiko evaluerings word in hierdie tesis saam hanteer deur die innoverende ontwerp, ontwikkeling en evaluering van 'n unieke stelsel vir die meting en ontleding van data. Alhoewel die skakel tussen hulle goed gedokumenteer is, word hierdie evaluering as afsonderlike antagonistiese entiteite hanteer. 'n Breë studie van die bestaande tradisionele en tegnologiese ondersteuningstelsels is gedoen om toepaslike metodes te identifiseer, om 'n gemeenskaplike tegnologiese platform vir outomatisering daar te stel. Die metodes wat gekies is vir die produktiwiteit en risiko bepalings is onderskeidelik werk monsterneming en die hersiende NIOSH opheffing vergelyking. Die outomatisering van hierdie prosedures word gefasiliteer deur middel van rekenaar visie en die gebruik van 'n Kinect™ 3D kamera. Die selfstandige C++ program integreer ‘n dubbelvolgings benadering om in reële tyd posisionele data van die werker en die werk-stuk te kry. Die OpenNI en OpenCV biblioteke word onderskeidelik gebruik om skeletale volging en beeld erkenning uit te voer. Die skeletale volger bepaal posisionele data van spesifieke gewrigte van die werker, terwyl die beeld erkenning komponent, 'n SURF implementering gebruik om 'n spesifieke werk-stuk binne die opname raam te identifiseer en te volg. Hierdie volgings tegnieke is berekenings intensief. Om werklike tyd uitvoering van die program te verseker, is Nvidia se CUDA gereedskapstel en liggewig boublokke geimplementeer. Die produktiwiteit meting-stelsel is 'n aaneenlopende monsterneming benadering van werk monsterneming. Die spoed van die werker se handbewegings en nabyheid aan die werkstuk word gebruik om die werker te klassifiseer as in een van vier moontlike toestande; besig, staties, onaktief of buite die raam. Benewens die werker gebaseerde metings, word daar ook data oor werkstukke bereken. Dit sluit in die aantal werkstukke verwerk deur 'n spesifieke werker, sowel as die gemiddelde en variasie in verwerkings tye. Die risiko-berekening is 'n outomatiese benadering van die hersiende NIOSH opheffing vergelyking. Die stelsel bereken wanneer die werker kontak maak en/of breek met die werkstuk en maak gebruik van die gewrigsposisies wat die skeletale volger aandui om die veranderlikes wat in die vermenigvuldigers gebruik word te bepaal. Die vermenigvuldigers word gebruik om die aanbevole maksimum gewig en die opheffing indeks te bereken. Die opheffing indeks dui aan of daar ‘n risiko vir die werker is om muskuloskeletale versteuring te ontwikkel. Benewens dui die vermenigvuldigers aan watter elemente die grootste bydra tot die risiko van die opheffingstaak maak. Die gebruiker-koppelvlak-ontwerp verseker dat die stelsel maklik is om te gebruik. Die koppelvlak vertoon ook die resultate van die studie sodat ontleders op enige tyd werker prestasie kan evalueer in reële tyd. Die outomatiese stelsel stel dus ontleders in staat om vinnig te reageer sodat probleme reggestel kan word. Die stelsel verminder ook die kompleksiteit vir die uitvoering van studies en dit elimineer menslike foute. Die tyd en koste vereis om die studie te doen, word verminder en die stelsel kan ‘n permanente instelling op fabriekvloere geword. Die ontwikkeling van die outomatiese stelsel maak die deur oop vir verdere ontwikkeling van die stelsel om uiteindelik daartoe te lei dat meer gedetailleerde evaluering van produktiwiteit en risiko bepaal kan word.

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