Ergonomic Aspects Research Articles

자동차 정비업체 근로자의 작업복 착용만족도와 개선요구도

In our modern society along with high speed economic growth and improvement of living conditions and through concentration of people in cities cars became essential necessities for people living in modern society. Due to social and economic conditions and for the need of recycling of materials and as a countermeasure for waste of materials importance of car service is stressed. In this connection need for improvement of working clothes which are suitable for safety and working efficiency in a difficult working environment is essential. However most of working clothes now being sold in the market are produced without consideration of ergonomic aspects of wearers of working clothes. For this reason there is need for basic research on development of working clothes which improve safety and comfort for working of car service workers. Accordingly in this study this author carried out research on fitness, level of satisfaction and dissatisfaction, suitability for movement and level of demand for improvement in working clothes with focus on workers at car service firms and direction for its improvement was explored. This study is intended to provide basic data for development of functional pattern of working clothes for car service workers in future.

The single-finger keyboard layout problem

The problem of designing new keyboard layouts able to improve the typing speed of an average message has been widely considered in the literature of the Ergonomics domain. Empirical tests with users and simple optimization criteria have been used to propose new solutions. On the contrary, very few papers in Operations Research have addressed this optimization problem. In this paper we firstly resume the most relevant problems in keyboard design, enlightening the related Ergonomics aspects. Then we concentrate on keyboards that must be used with a single finger or stylus, like that of portable data assistant, smartphones and other small devices. We show that the underlying optimization problem is a generalization of the well-known quadratic assignment problem (QAP). We recall some of the most effective metaheuristic algorithms for QAP and we propose some non-trivial extensions to the keyboard design problem. We compare the new algorithms through computational experiments with instances obtained from word lists of the English, French, Italian and Spanish languages. We provide on the web benchmark instances for each language and the best solutions we obtained.

Ergonomic Aspects Related to Surgeon Position in Laparoscopic Radical Prostatectomy

The aim is to evaluate the level of inclination of the surgeon's spinal column (ISSC) while performing laparoscopic radical prostatectomy (LRP) when using one trocar on each side of the patient abdomen ("torero" position) in two scenarios: With and without a thin head supporter adapted to the table. Based on trigonometric principles, we elaborated a formula to calculate the ISSC for a determined surgeon and surgical table while performing LRP in the torero position. The parameters considered were the width of the surgical table (m), the distance between the surgeon's anterior superior iliac spines (q), and the distance from the central point between the surgeon's anterior superior iliac spines to the surgeon's head (h). We used the formula alpha = 90 degree-cos(-1)(b/h) (where b = q/2 + m/2) in an Excel sheet to calculate the angle of inclination of the surgeon's spinal column. We applied the measures of 12 surgeons with different biotypes of our staff to calculate the ISSC with and without the thin head supporter. The use of a thin head supporter reduced the mean ISCC in the torero position from 36.1 +/- 3.73 degrees (range 31.3 to 49.8 degrees) to 22.1 +/- 4.9 degrees (range 18.7 to 32.9 degrees), which corresponds to a reduction of 38.8% in the mean angle of inclination. This difference was statistically significant (P < 0.001). The use of a thin head supporter adapted to the surgical table objectively reduces lateral inclination of the surgeon's spinal column in the torero position, making LRP a more comfortable procedure.

Percepção do consumidor com relação à embalagem de alimentos: tendências

This paper presents a review about food packaging sector in Brazil. It is known that simple changes in the habits of consumers and in the purchases decisions cause major quake in the packaging market. The ability of companies to understand these changes becomes increasingly important. The consumer’s requirement is by packaging more functional, and with clear and objective information. In the face of a consumer market increasingly demanding, the search for the "ideal packaging," which meets product’s needs as to contain, protect and carry, in addition to conserve, exhibit and sell has become a challenge for professionals from different areas. For the packaging design approach the closest to ideal, and meet the requirements laid down by law, we must consider the aesthetic and ergonomic aspects, with the lowest possible cost. Its note in this study that exist some concern about natural resources conservation and minimization of environmental impacts, through the use of packaging ecologically correct. Key words: food packaging, trends, design and ergonomics.

Evaluating the ergonomics of a student learning environment

Ergonomics is a key consideration of a student-learning environment. This paper examines aspects of ergonomics and application to the design of tables in three classrooms at a Midwestern university. Custom tables with power outlets and Internet access via Ethernet data ports were planned for classrooms in 2000 to facilitate a laptop program. However, table height, specifically thigh clearance from the seat to the bottom of the work surface, was not fully considered. The ergonomic analysis of the classrooms by an occupational therapy student led to the implementation of positive changes to the tables. The enhancement of the learning environment influences student comfort and productivity and can offset the cost of renovating the tables.

Ergonomics related to seating arrangements in the classroom: Worst in South East Asia? The situation in Sri Lankan school children

Sri Lanka is a resource-poor country in the South-East Asian region with good health indices. Ergonomics of children in educational environments is still novel in the region. An exploration into such issues and dissemination of the scientific evidence will stimulate policy makers in both education and health sector. An important ergonomic issue of the classroom is the seating arrangement. Essential aspects of seating include location of the chair and desk in relation to the blackboard and features of the chair and desk. Musculoskeletal pain is considered to be the most important negative effect due to mismatched ergonomics. A school-based descriptive cross sectional study was carried out in a district of Sri Lanka to ascertain the distribution of selected ergonomic factors related to seating arrangements in the classroom of school-going early adolescents and to assess their relationship to musculoskeletal pain. A sample of 1607 school children of Grade 6,7 and 8 were selected using stratified multi-stage cluster sampling method. There were 52.1% (N=838) females and 47.9% (N=769) males. Many ergonomic aspects related to classroom seating arrangements are not conducive for children. Children were seated with a mean distance of 398.04 cm (SD=132.09) to the blackboard. Nearly 23% of children had to turn more than 45~degrees to see the blackboard. A prevalence of > 80% mismatch was found between body dimensions of children and measurements of furniture. Musculoskeletal pain may have resulted from efforts to maintain stability while seated in incompatible furniture. Nearly 36% children complained of recurrent musculoskeletal pain. Musculoskeletal pain may have resulted from efforts to maintain stability while seated in incompatible furniture. Mismatched seat depth - buttock-popliteal length posed 1.59 times risk recurrent musculoskeletal pain. Despite, children perceived a good chair comfort. Use of backrest lowered the risk of recurrent pain. Results shows that programme planners can utilize such evidence to provide simple ergonomic solutions at national and school level.

Optimal ergonomics for laparoscopic surgery in minimally invasive surgery suites: a review and guidelines

With minimally invasive surgery (MIS), a man-machine environment was brought into the operating room, which created mental and physical challenges for the operating team. The science of ergonomics analyzes these challenges and formulates guidelines for creating a work environment that is safe and comfortable for its operators while effectiveness and efficiency of the process are maintained. This review aimed to formulate the ergonomic challenges related to monitor positioning in MIS. Background and guidelines are formulated for optimal ergonomic monitor positioning within the possibilities of the modern MIS suite, using multiple monitors suspended from the ceiling. All evidence-based experimental ergonomic studies conducted in the fields of laparoscopic surgery and applied ergonomics for other professions working with a display were identified by PubMed searches and selected for quality and applicability. Data from ergonomic studies were evaluated in terms of effectiveness and efficiency as well as comfort and safety aspects. Recommendations for individual monitor positioning are formulated to create a personal balance between these two ergonomic aspects. Misalignment in the eye-hand-target axis because of limited freedom in monitor positioning is recognized as an important ergonomic drawback during MIS. Realignment of the eye-hand-target axis improves personal values of comfort and safety as well as procedural values of effectiveness and efficiency. Monitor position is an important ergonomic factor during MIS. In the horizontal plain, the monitor should be straight in front of each person and aligned with the forearm-instrument motor axis to avoid axial rotation of the spine. In the sagittal plain, the monitor should be positioned lower than eye level to avoid neck extension.

Digital Human Modeling for Workspace Design

Digital human modeling (DHM) technology offers human factors/ergonomics specialists the promise of an efficient means to simulate a large variety of ergonomics issues early in the design of products and manufacturing workstations. It rests on the premise that most products and manufacturing work settings are specified and designed by using sophisticated computer-aided design (CAD) systems. By integrating a computer-rendered avatar (or hominoid) and the CAD-rendered graphics of a prospective workspace, one can simulate issues regarding who can fit, reach, see, manipulate, and so on. In this chapter, I briefly describe the development of various DHM methods to improve CAD systems. Past concerns about early DHM methods are discussed, followed by a description of some of the recent major developments that represent attempts by various groups to address the early concerns. In this latter context, methods are described for using anthropometric databases to ensure that population shape and size are well modeled. Efforts to integrate various biomechanical models into DHM systems also are described, followed by a section that outlines how human motions are being modeled in different DHM systems. In a final section, I discuss recent work to merge cognitive models of human performance with DHM models of manual tasks. Much has been accomplished in recent years to make digital human models more useful and effective in resolving ergonomics issues during the design of products and manufacturing processes, but much remains to be learned and applied in this rapidly evolving aspect of ergonomics.

A solar powered wireless computer mouse: Industrial design concepts

A solar powered wireless computer mouse (SPM) was chosen to serve as a case study for the evaluation and optimization of industrial design processes of photovoltaic (PV) powered consumer systems. As the design process requires expert knowledge in various technical fields, we assessed and compared the following: appropriate selection of integrated PV type, battery capacity and type, possible electronic circuitries for PV-battery coupling, and material properties concerning mechanical incorporation of PV into the encasing. Besides technical requirements, ergonomic aspects and design aesthetics with respect to good “sun-harvesting” properties influenced the design process. This is particularly important as simulations show users can positively influence energy balances by “sun-bathing” the PV mouse. A total of 15 SPM prototypes were manufactured and tested by actual users. Although user satisfaction proved the SPM concept to be feasible, future research still needs to address user acceptance related to product dimensions and user willingness to pro-actively “sun-bath” PV powered products in greater detail.

Hand‐held robotic instrument for dextrous laparoscopic interventions

Surgical instruments used in many types of minimally invasive procedures are rigid or only limitedly flexible. Some common tasks like suturing, require precise and dextrous movements that are difficult to perform by means of instruments with limited degrees of freedom (DOF). A hand-held lightweight and ergonomic robotic instrument with a 3-DOF roll-pitch-roll end-effector has been developed, which can be controlled by the surgeon with one hand like a conventional instrument. The instrument is composed by a handle part and an end-effector. The handle part has been developed taking into account a control mode study for laparoscopic instruments and it allows direct mapping between the orientation of handle and that of the end-effector. The instrument presented is the result of a global study involving mechanical, electronic and ergonomic aspects, with the aim of developing an instrument that enhances the dexterity of the surgeon while having an intuitive interface.

Usability testing of mobile ICT for clinical settings: Methodological and practical challenges

Background While much is known about how to do usability testing of stationary Electronic Patient Record (EPR) systems, less is known about how to do usability testing of mobile ICT systems intended for use in clinical settings. Aim Our aim is to provide a set of empirically based recommendations for usability testing of mobile ICT for clinical work. Method We have conducted usability tests of two mobile EPR systems. Both tests have been done in full-scale models of hospital settings, and with multiple users simultaneously. We report here on the methodological aspects of these tests. Results We found that the usability of the mobile EPR systems to a large extent were determined by factors that went beyond that of the graphical user interface. These factors include ergonomic aspects such as the ability to have both hands free, and social aspects such as to what extent the systems disturbs the face-to-face interaction between the health worker and the patient. Conclusions To be able to measure usability issues that go beyond what can be found by a traditional stationary user interface evaluation, it is necessary to conduct usability tests of mobile EPR systems in physical environments that simulate the conditions of the work situation at a high level of realism. It is further in most cases necessary to test with a number of test subjects simultaneously.

A questionnaire on the health effects of new technical equipment

This questionnaire study was aimed at finding out how new technical equipment affects the ergonomic health aspects of the working-age population. The study was carried out as a cross-sectional study by posting the questionnaire to 15 000 working-age Finns. The total number of participants was 6121. The questionnaire included 21 multiple choice questions on familiarity and usage of new technical devices (e.g. computers, mobile phones and digital televisions), prevalence of physical and mental symptoms, accidents associated with mobile phone use and an open-ended question on health and new technology. In statistical analyses of all data the usage of desktop computer and the usage of portable computer or mini-computer did not have influence on any physical symptoms. The influence can only be seen together with two-way interactions. The psychological symptoms were present in one- and two-way interactions. In the women’s age group of 41–50, the combined effects for usage of desktop computer and the usage of portable computer or mini-computer increase. For male subgroup the psychological symptoms increase only in the oldest age group (51–60). Relevance to industry A large-scale questionnaire offers a good reference for evaluating the prevalence of the symptoms from the use modern electrical devices. Finland is one of the leading countries in the design and utilization of electronics and thus offers an interesting viewpoint on such issues.

The effects of crank adjustments on handbike propulsion: A kinematic model approach

This study aims to realize a kinematic simulation of handcycling propulsion in order to investigate some ergonomic aspects specific to this mode of propulsion. We hypothesize that adjustments concerning crank position could minimize the joint range of upper extremity motions and/or avoid reaching the joint limit, which are considered as risk factors for repetitive strain injuries (RSI). One paraplegic and one able-bodied participants performed a handcycling test at a 70 rpm crank rate. A 3D analysis of upper extremity motion was made using a Vicon system (Vicon 370). From the data obtained, an inverse kinematic model at seven degrees of freedom was realized. Inputs to the model include the length of the user's arm segments, the position of the user's shoulder and the size of crank used. Joint kinematics are outputs from the model. The movement was simulated by moving the crank axis, or modifying the distance between the two cranks (±10 cm). From our results, the initial position (synchronous mode and a backrest angle close to 90°), like the “downward” and the “backward” positions, seems to generate a lower joint range of motion than other position adjustments. We were able to formulate a hypothesis as to an optimal crank adjustment to reduce risk factors for RSI. This study must be considered as a first step and needs further investigations with a larger population by seeking movement invariant in order to generalize our results. Relevance to industry Results from such a model would serve to guide future research and to help establish guidelines in order to reach an optimal arm crank wheelchair position based on user characteristics. The results of this study provide some ergonomic recommendations for handcycle design and in this way contribute to the further development of novel wheelchair design.

Medical and biological and ergonomic aspects of security of personal computer users

In this review article having experiment of decrease of the bad electromagnetic fields influence on the personnel computers customers organism is summed with the help of technical equipment.

A Methodology for the Design of Robotic Hands with Multiple Fingers

This paper presents a methodology that has been applied for a design process of anthropomorphic hands with multiple fingers. Biomechanical characteristics of human hand have been analysed so that ergonomic and anthropometric aspects have been used as fundamental references for obtaining grasping mechanisms. A kinematic analysis has been proposed to define the requirements for designing grasping functions. Selection of materials and actuators has been discussed too. This topic has been based on previous experiences with prototypes that have been developed at the Laboratory of Robotics and Mechatronics (LARM) of the University of Cassino. An example of the application of the proposed method has been presented for the design of a first prototype of LARM Hand.

Ergonomics policy in Indonesia.

Workers' conditions in accordance with their place of work are different from one area to another, especially in this reformation era where there are immense alterations in politics shown from the centralized government shifting to decentralization and district autonomy. Ergonomics problems in Indonesia are reviewed. In home industries, workers have to adjust themselves to their jobs, and ergonomic improvement may face significant impediments especially in small-scale industries. It is necessary to create or identify the most plausible model to be implemented in accordance with the conditions of districts, including low awareness about the relation between ergonomics and workers' productivity in producing goods and services and working processes scattered often at their own houses. As conditions conducive to ergonomics programs, district-level willingness to improve and increase the wealth of their society, recognition by businesses about the impacts of ergonomics on productivity and reduction of medical treatment costs may be mentioned. Labor unions support ergonomic improvements at production processes, and professionals and academicians are ready to assist, whereas national banks and foreign investment may encourage new technologies including ergonomics aspects. It is important to strengthen ergonomic improvement efforts in Indonesia through establishing district ergonomics improvement networks and ergonomics peer leaders with the support of continual training starting from the training of core leaders at the province level and extending to peer leaders at district level. This training should be made as simple as possible in order to facilitate innovations toward changes. Finally assistance is needed by the mentor teams in order to periodically monitor the improvements undertaken.

Effects of Field-of-View Restrictions on Speed and Accuracy of Manoeuvring

Effects of field-of-view restrictions on the speed and accuracy of participants performing a real-world manoeuvring task through an obstacled environment were investigated. Although field-of-view restrictions are known to affect human behaviour and to degrade performance for a range of different tasks, the relationship between human manoeuvring performance and field-of-view size is not known. This knowledge is essential to evaluate a trade-off between human performance, cost, and ergonomic aspects of field-of-view limiting devises like head-mounted displays and night vision goggles which are frequently deployed for tasks involving human motion through environments with obstacles. In this study the speed and accuracy of movement were measured in 15 participants (8 men, 7 women, 22.9 +/- 2.8 yr. of age) traversing a course formed by three wall segments for different field-of-view restrictions. Analysis showed speed decreased linearly with decreasing field-of-view extent, while accuracy was consistently reduced for all restricted field-of-view conditions. Present results may be used to evaluate cost and performance trade-offs for field-of-view restricting devices deployed to perform time-limited human-locomotion tasks in complex structured environments, such as night-vision goggles and head-mounted displays.

Design evolution through customer interaction with functional prototypes

There can be a tendency, even within companies who practice concurrent engineering, to limit customer involvement to the initial and final stages of the new product development process only. This invites the possibility that the customers' opinions will be lost or at least diluted during the intermediate stages of the process. A joint research project involving Loughborough University and the Central University of Technology, Free State has provided evidence, through several case studies, that physical models created via rapid prototyping enable the customer to be involved throughout the development process. The benefits associated with using physical models are discussed, showing that these models have a unique role to play in promoting customer involvement. The authors propose the method termed Customer Interaction with Functional Prototypes, which has been implemented during several new product development projects carried out in both academic and industrial environments. At present, the Customer Interaction with Functional Prototypes method is suitable for facilitating customer interaction primarily with the aesthetic and ergonomic aspects of simple consumer products or with stand-alone subsystems of more complex products. The method compliments the use of virtual prototyping and design analysis required to optimize the functional aspects of a product through the application of engineering science.

품질기능전개를 이용한 플라이어의 인간공학적 디자인

This study shows a way to develop ergonomic design of a plier through quality function deployment (QFD) approach. User needs for pliers, as well as the engineering characteristics which have influence on the ergonomic quality of pliers were determined from the interviews and questionnaires with various user groups. This information was entered in the house of quality, and the results show that the handle is the most important quality factor. A new model was proposed in which ergonomic and gender aspects were considered. QFD is considered a suitable method especially for the manufacturing and/or design fields where biomechanical or physiological background is not present.

The Health and Wellbeing of Adults Working in Early Childhood Education

THIS ARTICLE REPORTS the results of a survey of 168 New Zealand early childhood workers and describes their health status, behaviours and concerns. The respondents included 73 childcare teachers, 58 kindergarten teachers and 37 home-based educators. Although 92 per cent of respondents reported that they had good or excellent health, statistically significant differences were found between the groups for days absent because of illness, accidental injuries, job-related stress and ergonomic aspects of their work. All groups reported an increase in various physical symptoms since working with children, in particular backaches, muscle strain and fatigue. One-quarter of respondents experienced an illness related to their work with children during the past year, most commonly respiratory and gastrointestinal illnesses. The study alerts early childhood education employers to the importance of managing health issues such as workload and stress, occupational injuries, the provision of an ergonomically healthy work environment and adequate conditions of employment.