• The Journal of the Korea Contents Association
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• v.7 no.6
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• pp.69-78
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• 2007

In recent years, embedded mobile systems have been expanding their application domains from embedded portable devices which only execute a specialized application such as MP3 player or digital camcoder to digital convergence devices which execute more complicated applications converged various functionalities such as video and audio play, digital dictionary, DMB, games, phone, etc. As it requires the increasing hardware performance such as more faster CPU and more larger RAM, display, disk size, it has brought about a corresponding increase in power consumption. However, coupled with relatively small gains in battery capacity over recent years, the importance of software architecture including intelligent power management has become paramount. In this paper, we have ported UbiFOSTM with energy saving techniques on the ARM9-based MBA2440 platform. For energy savings, we adapted the dynamic power management and the device power management schemes based on monitoring workload. Experimental results with some well-known applications show that proposed low power technique could save energy up to 24 %.

• The Journal of Korean Association of Computer Education
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• v.11 no.2
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• pp.107-117
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• 2008

The agent system that can adjust the workload dynamically through thc periodical monitoring of the VoD system comprises the agency part interfacing the VoD system and the intelligence part reasoning or learning the facts required for the adjustment of workload. This paper proposes a learning method that can apply to the intelligence part of the agent system. The proposed method can adjust the workload more efficiently by the rule's reasoning process and case-based learning process. An experiment of implementing a simulator was conducted to see whether or not application of the proposed method to VoD systems is efficient. As a result of the experiment, it was found that the throughput and the average waiting time of the VoD server were relatively improved when the proposed method was applied compared to existing means.

• IE interfaces
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• v.25 no.1
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• pp.114-126
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• 2012

This study describes a real-time location monitoring system developed for efficient operation of workplace in plant equipment maker. This monitoring system can be applied for indoor and outdoor working environment respectively. By using the real-time tracking system based on RTLS, it is possible to track worker's movement and location of working object under indoor working environment. For outdoor working environment, the real-time monitoring system based on IDGPS is applied for work safety and balanced workload. A case study is provided to evaluate the performance of the real-time monitoring system.

• Journal of Navigation and Port Research
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• v.46 no.3
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• pp.209-215
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• 2022

On the Jeju coast, international cruise ships, passenger ships, and other ships pass frequently, as well as many fishing boats. Thus, there is a high risk of marine accidents and frequent ship collisions. Accordingly, it is urgent to establish a coastal VTS for systematic safety management of ships passing through the coastal waters of Jeju. The purpose of this study was to set the area of the VTS to be newly established. In this study, to calculate the workload of the VTS operators, a formula was proposed that reflects the monitoring workload considering the monitoring frequency and required time for target as well as non-target ships and the workload for ship collision situations. The proposed formula was applied to the newly established VTS area in Jeju. Three control sectors were set up in each VTS center. The average number of workstations per hour was approximately 1, so the division between sectors was appropriate. Thus, it was deduced that there would be no workload for the VTS operators. It is expected that the method proposed in this study can be used as primary data for calculating the appropriate number of workstations for the current VTS, and setting the VTS area for a new coastal VTS in the future.

• Journal of Internet Computing and Services
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• v.18 no.4
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• pp.79-87
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• 2017

Company A, an embedded system manufacturer, provides its products to Company P which is the parent company of Company A. Both companies learned that they needed to find over 4,000 bugs before market release in order to meet the acceptable quality level. Traditionally, they had utilized time-series line graphs as their common performance measurement tool. These graphs compared accumulated numbers of bugs fixed with accumulated numbers of bugs found. Engineers in Company A had been under pressure to improve the process capacity because the line for bugs fixed was always below than the line for bugs found. By using a newly designed Bipolar diagram, engineers in Company A analyzed the process performance. And they were in a position to be more flexible for internal or inter-companies meeting. Authors explain an empirical study of a graphical and practical performance measurement tools relating to mainly the Bipolar diagram. As a result, the Bipolar diagram provides workload monitoring and performance measurement functions in a given timeframe by using the concepts of Optimum Process Line (or band) and Fair Process Capacity Zone.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.4
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• pp.69-75
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• 2019

Since gasoline engines are based on a combination of a cast iron liner and an aluminum block, which have different thermal properties and stiffnesses, bore shape distortion is likely to occur during honing due to uneven thermal deformation. To solve this problem, many tests and evaluations are needed to support the development of a high-performance honing stone with low heat generation. Moreover, performance evaluation, which depends on inspection and observation after work, often requires much trial and error to optimize tool design, due to challenges in the accurate interpretation of results. This study confirmed that the assessment of grinding capability was clarified by evaluating performance under severe work conditions and by in-situ measurement and recording of current consumption (workload) and heat generation during operation. As a result of using a honing stone with excellent grinding performance in engine block manufacture-in which cylinder bore distortion caused by thermal deformation during manufacture is a problem-a noticeable improvement in the degree of cylindricity was observed.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.24.1-24.15
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• 2023

Background: The construction workers are vulnerable to fatigue due to high physical workload. This study aimed to investigate the relationship between overwork and heart rate in construction workers and propose a scheme to prevent overwork in advance. Methods: We measured the heart rates of construction workers at a construction site of a residential and commercial complex in Seoul from August to October 2021 and develop an index that monitors overwork in real-time. A total of 66 Korean workers participated in the study, wearing real-time heart rate monitoring equipment. The relative heart rate (RHR) was calculated using the minimum and maximum heart rates, and the maximum acceptable working time (MAWT) was estimated using RHR to calculate the workload. The overwork index (OI) was defined as the cumulative workload evaluated with the MAWT. An appropriate scenario line (PSL) was set as an index that can be compared to the OI to evaluate the degree of overwork in real-time. The excess overwork index (EOI) was evaluated in real-time during work performance using the difference between the OI and the PSL. The EOI value was used to perform receiver operating characteristic (ROC) curve analysis to find the optimal cut-off value for classification of overwork state. Results: Of the 60 participants analyzed, 28 (46.7%) were classified as the overwork group based on their RHR. ROC curve analysis showed that the EOI was a good predictor of overwork, with an area under the curve of 0.824. The optimal cut-off values ranged from 21.8% to 24.0% depending on the method used to determine the cut-off point. Conclusion: The EOI showed promising results as a predictive tool to assess overwork in real-time using heart rate monitoring and calculation through MAWT. Further research is needed to assess physical workload accurately and determine cut-off values across industries.

• IEMEK Journal of Embedded Systems and Applications
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• v.11 no.1
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• pp.21-27
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• 2016

An integrated display software platform for small UAV is developed based on parallel processing technique in this paper. When the small UAV with high-performance camera and avionic modules is employed to various surveillance-related missions, it is important to reduce the operator's workload and increase the monitoring efficiency. For this purpose, it is needed to develop an efficient monitoring software enable to manipulate the image and flight data obtained during flight within the given processing time and display them simultaneously. In this paper, we set up requirements and suggest the architecture for the software platform. The integrated software platform is implemented with parallel processing scheme. Based on AR drone, we verified that the various data are concurrently displayed by the suggest software platform.

• Safety and Health at Work
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• v.13 no.3
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• pp.350-356
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• 2022

Background: Although sick leave is a complex phenomenon, it is believed that there is potential for prevention at the workplace. However, little is known about this potential and what specific measures should be implemented. The purpose of the study was to identify perceived reasons to take work-related sick leave and to suggest preventive measures. The study was completed before the COVID-19 pandemic emerged, and the risk factors identified may have been amplified during the pandemic. Methods: An in-depth cross-sectional survey was conducted across a randomly selected sample of hospital nurses in Norway. The national sample comprised 1,297 nurses who participated in a survey about their sick leave during the previous 6 months. An open-ended question about perceived reasons for work-related sick leave was included to gather qualitative information. Results: Among hospital nurses, 27% of the last occurring sick leave incidents were perceived to be work-related. The most common reasons were high physical workload, high work pace, sleep problems, catching a viral or bacterial infection from patients or colleagues, and low staffing. Conclusions: Over a quarter of the last occurring sick leave incidents among Norwegian hospital nurses are potentially preventable. To retain and optimize scarce hospital nursing resources, strategies to reduce work-related sick leave may provide human and financial benefits. Preventive measures may include careful monitoring of nurses' workload and pace, optimizing work schedules to reduce the risk of sleep problems, and increasing staffing to prevent stress and work overload.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.4
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• pp.215-221
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• 2022

본 연구는 민간항공 조종사 훈련 및 평가에 중요하게 고려되고 있는 8가지 핵심 역량 향상을 위한 기초자료 마련을 위해 수행되었으며, 그 중 가장 중요하다고 판단되는 상황인식(situation awareness) 및 작업부하 관리에 대해 분석하였다. 예비 조종사를 대상으로 항공기 접근 및 착륙 단계를 진행하는 동안 PM(pilot monitoring) 역할을 수행하며 인식하는 항공기 상황과 작업부하량에 대해 평가하였다. 평가 시나리오는 기본비행훈련장치(basic aviation training device)를 사용하여 지형적 상황인식, 공간/시간적 상황인식, 시스템 상황인식, 환경적 상황인식을 평가할 수 있는 요소로 구성하였으며, 모니터링 도중 의도적인 주의분산 상황을 추가하였다. 연구 결과, 전체 비행 단계에 대한 상황인식은 32.3%이고, 지형적 상황인식(60.3%)이 가장 높고, 시스템 상황인식(18%)이 가장 낮은 것으로 나타났다. NASA-TLX 평가방법으로 측정한 작업부하량은 10.8점(20점 만점)으로 나타났다. 또한, 기초공중항법학을 수강한 예비 조종사들이 대체로 높은 상황인식을 하였고, 작업부하 결과는 지형적 상황인식과 밀접한 상관관계를 가지고 있었다.