• 드라이브 ㆍ 컨트롤
• /
• 제19권4호
• /
• pp.29-35
• /
• 2022

In this paper, we developed a workload index for monitoring the durability test using operation information of an excavator. First, the acceleration and cylinder pressure were selected as load factors by analyzing operation data. Through load correlation analysis according to each load factor, Root Mean Square (RMS) and Work Load Range (WLR) were respectively derived as a load feature representing mechanical load. In addition, the workload index was used to quantify load features. For applying the workload index to monitoring, a real-time monitoring system consisting of sensors and embedded controller was installed on the excavator and the system was integrated with a remote monitoring environment using a wireless network. Results of load monitoring and analysis verified that the developed workload index was effective from the viewpoint of the relative comparison of the workload.

• 대한인간공학회지
• /
• 제29권1호
• /
• pp.17-24
• /
• 2010

There has been recent interest in intelligent vehicle technologies, such as advanced driver assistance systems (ADASs) or in-vehicle information systems (IVISs) that offer a significant enhancement of safety and convenience to drivers and passengers. However, unsuitable design of HMI (Human Machine Interface) must increase driver distraction and workload, which in turn increase the chance of traffic accidents. Distraction in particular often occurs under a heavy driving workload due to multitasking with various electronic devices like a cell phone or a navigation system while driving. According to the 2005 road traffic accidents in Korea report published by the ROad Traffic Authority (ROTA), more than 60% of the traffic accidents are related to driver error caused by distraction. This paper suggests the structure of vehicle environment for real-time driving behavior monitoring system while driving which is can be used the driver workload management systems (DWMS). On-road experiment results showed the feasibility of the suggested vehicle environment for driving behavior monitoring system.

• 제어로봇시스템학회논문지
• /
• 제8권4호
• /
• pp.303-307
• /
• 2002

Virtual hosting is a typical service to connect each directory of site and domain name. If traffic amounts may increase at one site present in the server, then it affects traffic amounts of other sites as well (including the sites which have flew requests). To overcome this problem, we suggest a simple feedback-control concept for the system by periodically monitoring the traffic and properly actuating traffic dispersions by investigating the log file. Specifically, large files are to be served in a backup server (to reduce the workload of the main server) by changing their own URL's in html format. In other words, it automatically redistributes the workload by using the URL. Furthermore, we also use the redirecting method by just adding html tags to html header. This method efficiently handles the workload and maintains the capability of the server effectively to the varying workload.

• 국제학술발표논문집
• /
• The 6th International Conference on Construction Engineering and Project Management
• /
• pp.179-182
• /
• 2015

Detecting and assessing human-related risks is critical to improve the on-site safety condition and reduce the loss in lives, time and budget for construction industry. Recent research in neural science and psychology suggest inattentional blindness that caused by overload in working memory is the major cause of unexpected human related accidents. Due to the limitation of human mental workload, laborers are vulnerable to unexpected hazards while focusing on complicated and dangerous construction tasks. Therefore, detecting the risk perception abilities of workers could help to identify vulnerable individuals and reduce unexpected injuries. However, there are no available measurement approaches or devices capable of monitoring construction workers' mental conditions. The research proposed in this paper aims to develop such a measurement framework to evaluate hazards through monitoring electroencephalogram of labors. The research team developed a wearable safety monitoring helmet, which can collect the brain waves of users for analysis. A bispectrum approach has been developed in this paper to enrich the data source and improve accuracy.

• Safety and Health at Work
• /
• 제6권3호
• /
• pp.192-199
• /
• 2015

Background: Overweight, obesity, and cardiovascular disease risk factors are prevalent among firefighters in some developed countries. It is unclear whether physical activity and cardiopulmonary fitness reduce cardiovascular disease risk and the cardiovascular workload at work in firefighters. The present study investigated the relationship between leisure-time physical activity, cardiopulmonary fitness, cardiovascular disease risk factors, and cardiovascular workload at work in firefighters in Hong Kong. Methods: Male firefighters (n = 387) were randomly selected from serving firefighters in Hong Kong (n = 5,370) for the assessment of cardiovascular disease risk factors (obesity, hypertension, diabetes mellitus, dyslipidemia, smoking, known cardiovascular diseases). One-third (Target Group) were randomly selected for the assessment of off-duty leisure-time physical activity using the short version of the International Physical Activity Questionnaire. Maximal oxygen uptake was assessed, as well as cardiovascular workload using heart rate monitoring for each firefighter for four "normal" 24-hour working shifts and during real-situation simulated scenarios. Results: Overall, 33.9% of the firefighters had at least two cardiovascular disease risk factors. In the Target Group, firefighters who had higher leisure-time physical activity had a lower resting heart rate and a lower average working heart rate, and spent a smaller proportion of time working at a moderate-intensity cardiovascular workload. Firefighters who had moderate aerobic fitness and high leisure-time physical activity had a lower peak working heart rate during the mountain rescue scenario compared with firefighters who had low leisure-time physical activities. Conclusion: Leisure-time physical activity conferred significant benefits during job tasks of moderate cardiovascular workload in firefighters in Hong Kong.

• 디지털융복합연구
• /
• 제11권5호
• /
• pp.347-354
• /
• 2013

양질의 의료 서비스를 요구하는 환자들은 증가하는 반면 의사나 간호사와 같은 전문 의료 인력은 한정되어 있어 그들에게 가해지는 업무 부담이 과중하게 부여되고 있는 실정이다. 이러한 문제를 해결하기 위한 대안으로 USN(Ubiquitous Sensor Network)을 이용한 환자 모니터링 시스템이 대두되고 있다. 본 논문에서는 USN을 산부인과에 적용하여 간호사의 업무 부담을 줄이기 위해 산모 모니터링 시스템 모델을 설계하였다. 효율성 평가는 서울소재 대학병원(S, K 병원) 두 곳을 모델로 설정하여 의사의 처방에 따른 측정 주기를 산출하여 실시하였으며, 그 결과는 간호사 1인이 12명의 환자(자연분만 6명, 자연분만 외 출산 6명)를 케어하는 경우 입원기간(5일 기준) 동안에 1,260분이 경감되는 것으로 나타났다. 또한 간호사의 기존 업무량과 모니터링 시스템 적용 후 업무량을 비교해 보았을 때 자연분만 산모의 경우 산모 수가 1명씩 증가함에 따라 하루에 50분씩, 자연분만 외 수술 산모의 경우 산모 수가 1명씩 증가함에 따라 하루에 130분씩 업무량 감소 효과가 있는 것으로 나타났다.

• 국제학술발표논문집
• /
• The 9th International Conference on Construction Engineering and Project Management
• /
• pp.1242-1242
• /
• 2022

Annually, several construction workers fall ill, are injured, or die due to heat-related exposure. The prevalence of work-related heat illness may rise and become an issue for workers operating in temperate climates, given the increase in frequency and intensity of heatwaves in the US. An increase in temperature negatively impacts physical exertion levels and mental state, thereby increasing the potential of accidents on the job site. To reduce the impact of heat stress on workers, it is critical to develop and implement measures for monitoring physical exertion levels and mental state in hot conditions. For this, limited studies have evaluated the utility of wearable biosensors in measuring physical exertion and mental workload in hot conditions. In addition, most studies focus solely on male participants, with little to no reference to female workers who may be exposed to greater heat stress risk. Therefore, this study aims to develop a process for objective and continuous assessment of worker physical exertion and mental workload using wearable biosensors. Physiological data were collected from eight (four male and four female) participants performing a simulated drilling task at 92oF and about 50% humidity level. After removing signal artifacts from the data using multiple filtering processes, the data was compared to a perceived muscle exertion scale and mental workload scale. Results indicate that biosensors' features can effectively detect the change in worker physical and mental state in hot conditions. Therefore, wearable biosensors provide a feasible and effective opportunity to continuously assess worker physical exertion and mental workload.

• 한국시뮬레이션학회논문지
• /
• 제12권3호
• /
• pp.69-81
• /
• 2003

To manage a cluster of distributed server systems, a number of management aspects should be considered in terms of configuration management, fault management, performance management, and user management. System performance monitoring and reporting take an important role for performance and fault management. In this paper, we present distributed system architecture modeling of a performance monitoring and reporting tool. Modeling architecture of four subsystems are introduced: node agent, data collection, performance management & report, and DB schema. The performance-related information collected from distributed servers are categorized into performance counters, event data for system status changes, service quality, and system configuration data. In order to analyze those performance information, we use a number of ways to evaluate data corelation. By using some results from a real site of a company and from simulation of artificial workload, we show the example of performance collection and analysis. Since our report tool detects system fault or node component failure and analyzes performances through resource usage and service quality, we are able to provide information for server load balancing, in short term view, and the cause of system faults and decision for system scale-out and scale-up, in long term view.

• 한국멀티미디어학회논문지
• /
• 제9권7호
• /
• pp.904-913
• /
• 2006

VoD(Video on Demand) 시스템의 QoS(Quali쇼 of Service)는 클라이언트들의 스트림 서비스 요청이 시스템으로부터 거부되거나 서비스 도중에 손실되는 장애현상의 발생을 줄임으로써 향상시킬 수 있다. 본 연구에서는 VoD 시스템의 작업과정을 주기적으로 모니터링하며, 동적으로 작업부하(workload)를 조정하여 장애현상의 발생을 줄임으로써 성공적인 스트림 서비스 처리량(throughput)을 증가시킬 수 있는 동적 작업부하조정기 (Dynamic Workload Balancer) 모델을 제안하였다. 제안된 모델은 에이전트개념을 사용하여 VoD 시스템과는 서로 독립적으로 작동할 수 있게 하였으며, VoD 시스템과 인터페이스를 하는 에이전시(Agency) 부분과 작업부하 조정에 필요한 조치를 추론하거나 학습하는 인텔리전스(Intelligence) 부분으로 구성된다. 그리고 제안된 모델을 VoD 시스템에 적용하는 경우에 실효성이 있는지를 시뮬레이터를 구현하여 실험하였다. 실험의 결과, 제안된 모델을 적용하면 기존의 방법을 적용한 경우보다 상대적으로 QoS가 향상된다는 것을 알 수 있었다.

• 정보과학회지
• /
• 제31권4호
• /
• pp.51-61
• /
• 2013