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1.
This study utilized a portable data logger to measure the wrist angles and forearm flexor and extensor electromyography (EMG) of 21 hairstylists. The hairstylists were divided into two groups, one with 11 barbers (9 males and 2 females) specializing in men's hairdressing, and one with 10 hairdressers (2 males and 8 females) specializing in women's hairdressing. The standard haircut task was divided into three subtasks: hair cutting, washing and blow-drying. The mechanical exposures of the overall task and subtasks were quantified to compare how subtasks, occupational groups, and gender groups differ. Experimental results show that the average time to finish a woman's haircut (51.4 min) is significantly longer than that for a man's haircut (35.6 min) (p < 0.005). Female hairstylists had significantly greater EMG activity than male hairstylists did (p < 0.001). The non-dominant hands of hairdressers have significantly higher overall wrist velocity than those of barbers (p < 0.005). Analytical results suggest that the relatively higher force exertion and wrist velocity of female hairstylists combined with prolonged exposure may account for the higher rate of hand/wrist pain in female hairdressers than in male barbers. 相似文献
2.
Ward JS 《Applied ergonomics》1971,2(3):171-177
An investigation is described to ascertain optimum work surface heights in the kitchen, using several ergonomic techniques. 相似文献
3.
The theme of large temporal span of cognition is emerging as a key issue in cognitive anthropology and ergonomics. We will
consider it through the analysis of a musical composition process, that of Voi(rex) by Philippe Leroux, in which sketches and score writing are articulated through the use of different kinds of computer software.
After presenting the data collecting method, we will consider the analysis of the resulting data concerning the writing of
two movements of Voi(rex). Such an analysis will allow us: (1) to draw methodological conclusions about the time and mode of inquiry; (2) to specify
the notion of situated cognition in situations essentially pre-established by the actor; (3) to set out two families of theoretical
results relating to large temporal span cognitive phenomena: the first concerns the notion of an idea and its role in the development of the creative process; the second deals with the notion of the appropriation of tools and the making of situated individual cognition.
相似文献
Nicolas DoninEmail: |
4.
《Ergonomics》2012,55(11):1109-1123
Increasing requirements for aircraft keyboards have indicated inadequacies in ergonomic standards for airborne environments, in particular for tasks involving unskilled, discontinuous data entry, with emphasis on accuracy rather than speed. Four experiments are reported from a programme of research aimed at the development and application of methodologies for assessing factors relevant to keyboard design. Experiment 1 demonstrated that the effects of various aircrew gloves on a representative aircraft data entry task are highly situation specific. Experiment 2 showed that gloves impaired performance on a high compatibility continuous keying task, with relatively high keying rates, and that this impairment was not reduced by additional auditory feedback. Experiment 3 demonstrated that the high compatibility keying task provided a successful methodology for investigating the effects of key displacement and resistance on speed and accuracy. Experiment 4 indicated the relative contributions of reduced tactility and mobility to the effects on keying and manipulative performance caused by aircrew gloves. Together, these experiments suggest that kinaesthetic and tactile feedback associated with keying are relatively unaffected by aircrew gloves, and that restrictions on mobility caused by gloves may be more important for continuous data entry involving relatively high keying rates 相似文献
5.
Qiming Liu Yongjun Li Lixiong Cao Fei Lei Qiong Wang 《Structural and Multidisciplinary Optimization》2018,57(3):965-975
Vehicle lightweight and safety design becomes an increasingly critical issue nowadays. In order to improve the crashworthiness of side impact and roof crush with the consideration of the manufacturing process, a new composite B-pillar structure with ply drop-off is proposed in this paper. It improves the crashworthiness by changing the section thickness of structure and reduces the weight of B-pillar. The ply drop-off regions on the outer part and inner part of B-pillar are divided into three sub-laminates respectively, named as thick panel, taper panel and thin panel. The thickness of the panel are determined by the number of lay-up. Based on traditional sensitivity analysis, this paper derives some new equations and clearly evaluates and quantifies the importance of uncertainty design parameters. Finally, the comprehensive performance of the lightweight and crashworthiness for the composite B-pillar with ply drop-off is improved through structural optimization. 相似文献
6.
An approach to the problem of automatically locating the melting layer is outlined. The approach uses image analysis techniques on dual and single polarization radar data. 相似文献
7.
Most modern Web robots that crawl the Internet to support value-added services and technologies possess sophisticated data collection and analysis capabilities. Some of these robots, however, may be ill-behaved or malicious, and hence, may impose a significant strain on a Web server. It is thus necessary to detect Web robots in order to block undesirable ones from accessing the server. Such detection is also essential to ensure that the robot traffic is considered appropriately in the performance and capacity planning of Web servers. Despite a variety of Web robot detection techniques, there is no consensus regarding a single technique, or even a specific ??type?? of technique, that performs well in practice. Therefore, to aid in the development of a practically applicable robot detection technique, this survey presents a critical analysis and comparison of the prevalent detection approaches. We propose a framework to classify the existing detection techniques into four categories based on their underlying detection philosophy. We compare the different classes to gain insights into those characteristics that make up an effective robot detection scheme. Finally, we discuss why the contemporary techniques fail to offer a general solution to the robot detection problem and propose a set of key ingredients necessary for strong Web robot detection. 相似文献
8.
Carlos A. CataniaAuthor Vitae Carlos García GarinoAuthor Vitae 《Computers & Electrical Engineering》2012,38(5):1062-1072
Automatic network intrusion detection has been an important research topic for the last 20 years. In that time, approaches based on signatures describing intrusive behavior have become the de-facto industry standard. Alternatively, other novel techniques have been used for improving automation of the intrusion detection process. In this regard, statistical methods, machine learning and data mining techniques have been proposed arguing higher automation capabilities than signature-based approaches. However, the majority of these novel techniques have never been deployed on real-life scenarios. The fact is that signature-based still is the most widely used strategy for automatic intrusion detection. In the present article we survey the most relevant works in the field of automatic network intrusion detection. In contrast to previous surveys, our analysis considers several features required for truly deploying each one of the reviewed approaches. This wider perspective can help us to identify the possible causes behind the lack of acceptance of novel techniques by network security experts. 相似文献
9.
This paper illustrates the effect of stiction in actuators on closed loop performance and the importance of techniques, to be incorporated in the monitoring system, for automatic detection of the onset of this phenomenon. Three different techniques are compared on the basis of simulation by means of stiction models and it is shown how loop variables are affected by stiction parameters and by process characteristics. A major finding is that every technique has an uncertainty region where no decision can be taken in the absence of further information about the process. The application on industrial data, recorded on loops affected by stiction during routine plant operation, allows to confirm this result and to assess relative efficiency of the techniques. A simple test to be performed directly on the plant is also proposed to solve the remaining uncertain cases. 相似文献
10.
One of the major issues of mesh generation today is access to geometry in an accurate and efficient manner. This paper will review several of the issues associated with accessing geometry for mesh generation. This paper will also evaluate alternative techniques for accessing geometry and review how these techniques address, or do not address, the issues related to geometry access for mesh generation. The techniques for geometry access to be reviewed include: translation and healing, discrete representations, direct geometry access, and unified topology accessing geometry directly. The intent of this paper is to provide an overview to the alternative approaches and how they address the specific issues related to accessing geometry for mesh generation. It is not the intent of this paper to provide detailed algorithms related to accessing or repairing geometry data. 相似文献
11.
We examined the effects of load carriage position on the energy cost of walking defined as the ratio of the 2-min steady-state oxygen consumption to the speed and economical speed. Fourteen healthy men walked on a treadmill at various speeds without and with load on the lower and upper back, which corresponded to 15% of their body mass. The energy cost of walking significantly decreased during walking with load than without load at slower speeds. A significant decrease in the energy cost of walking was also observed while carrying the load on the upper back than on the lower back at 60-80 m/min. The economical speed significantly decreased when carrying the load on the upper and lower back, and it was significantly correlated with body height. These findings suggest that an optimal carrying method is evident to reduce physical stress during walking with loads. 相似文献
12.
OBJECTIVE: This study aims to evaluate safety and accessibility of an advanced life support (ALS) ambulance interior. BACKGROUND: The standard ambulance's interior design is unsatisfactory based on perceived discomfort and postures that constrain paramedics and medical staff, resulting in unsafe treatment of patients, mainly when being transported. METHODS: Two procedures were used to evaluate performance during a wide range of rescue tasks: a survey, based on questionnaires, interviews, and observation of paramedics performing routine tasks; and upper body and back posture analysis, based on postural considerations. RESULTS: Findings revealed that 74% of the paramedics stated that the location of the paramedic's seat is inefficient while they perform clinical procedures; 94% found the bench uncomfortable; 77% felt that the vertical distance between the bench and the stretcher is too far; and 86% needed to steady themselves when the vehicle was moving. Posture analysis showed that paramedics undergo several nonneutral back postures, including twisted back (>20 degrees) and sitting with back flexion between 20 degrees and 45 degrees. CONCLUSION: Because the interior of the ALS ambulance was found to be unsatisfactory both to paramedics and patients, alternative design issues are proposed. APPLICATION: The suggested practical layout contains four main modifications: (a) replacing the bench with two adjustable paramedic seats, (b) redesigning the medical cabinet for easy access, (c) adding an adjustable folding seat opposite the two new seats, and (d) adding a swiveling base and lifting apparatus that will accommodate the stretcher and enable better accessibility to patients by the paramedic personnel. 相似文献
13.
In this paper we give evidence that it is possible to characterize and detect those potential users of false invoices in a given year, depending on the information in their tax payment, their historical performance and characteristics, using different types of data mining techniques. First, clustering algorithms like SOM and neural gas are used to identify groups of similar behaviour in the universe of taxpayers. Then decision trees, neural networks and Bayesian networks are used to identify those variables that are related to conduct of fraud and/or no fraud, detect patterns of associated behaviour and establishing to what extent cases of fraud and/or no fraud can be detected with the available information. This will help identify patterns of fraud and generate knowledge that can be used in the audit work performed by the Tax Administration of Chile (in Spanish Servicio de Impuestos Internos (SII)) to detect this type of tax crime. 相似文献
14.
Ahmad Karim Rosli Bin Salleh Muhammad Shiraz Syed Adeel Ali Shah Irfan Awan Nor Badrul Anuar 《浙江大学学报:C卷英文版》2014,15(11):943-983
In recent years, the Interact has enabled access to widespread remote services in the distributed computing environment; however, integrity of data transmission in the distributed computing platform is hindered by a number of security issues. For instance, the botnet phenomenon is a prominent threat to Intemet security, including the threat of malicious codes. The botnet phenomenon supports a wide range of criminal activities, including distributed denial of service (DDoS) attacks, click fraud, phishing, malware distribution, spam emails, and building machines for illegitimate exchange of information/materials. Therefore, it is imperative to design and develop a robust mechanism for improving the botnet detection, analysis, and removal process. Currently, botnet detection techniques have been reviewed in different ways; however, such studies are limited in scope and lack discussions on the latest botnet detection techniques. This paper presents a comprehensive review of the latest state-of-the-art techniques for botnet detection and figures out the trends of previous and current research. It provides a thematic taxonomy for the classification of botnet detection techniques and highlights the implications and critical aspects by qualitatively analyzing such techniques. Related to our comprehensive review, we highlight future directions for improving the schemes that broadly span the entire botnet detection research field and identify the persistent and prominent research challenges that remain open. 相似文献
15.
Automatic fire detection system is a system that is capable of assessing environmental factors and their effects on the environment as well as predicting the occurrence of fire in the early stages and even before the outbreak. There are two perspectives in fire detection: fire detection in forests or jungles and fire detection in occupied or residential areas. Automatic fire detection has attracted increased attention due to its importance in decreasing fire damage. There are many studies that have considered appropriate techniques for early fire detection. In recent years researches have been studying technical developments in this field aimed at exploiting wireless communications networks, detection systems and fire prediction systems design. In this paper the automatic fire detection researches using intelligent techniques from 2000 to 2010 is reviewed. We could classify researches to four categories: fire detectors, reduce false alarms systems, fire data analysis and fire predictors. We also classify the intelligent techniques outlined in the researches for each category. 相似文献
16.
Model of elliptical trainer and 3D human body are built with the ergonomic module of CATIA V5 to study ergonomic characteristics of fitness equipments as a preliminary evaluation of elliptical trainer. 相似文献
17.
Injection molding technology and its different modifications represent established processes for manufacturing polymer products
with high accuracy in large scale production. Enhanced machine and tool technologies like evacuation units and special temperization
systems have already been adapted to the molding of microstructures with high aspect ratios. Cycle times are actually in the
range of minutes and depend on the geometry of the microstructures and the materials used. Based on injection molding of lost
plastic microforms new processes for the manufacturing of ceramic or metal microstructures are being developed.
Received: 14 November 1996/Accepted: 25 November 1996 相似文献
18.
P. -F. Indermü hle G. Schü rmann G. -A. Racine N. F. de Rooij 《Sensors and actuators. A, Physical》1997,60(1-3):186-190
We have developed a new process to fabricate arrays of cantilevers with integrated tips for atomic force microscope (AFM) imaging and a piezoelectric layer for vertical actuation and detection. A good homogeneity of the tip shape is obtained thanks to a self-sharpening effect. The cantilevers have been characterized mechanically and electrically. 相似文献
19.