• 한국기계가공학회지
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• 제14권6호
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• pp.49-56
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• 2015

For designing working devices of construction equipment, it is necessary to consider not only sufficient working ability but also available working range. Therefore, it is important to select the appropriate pivot positions of links. This paper presents a study on selection of pivot points of links used in construction equipment. To analyze the effect of each pivot point, a design program for pivot selection is developed. A conventional pivot design method requires a complicated process because it needs to create a certain working position manually to evaluate its performance. However, the developed program includes an automatic link assembly algorithm; thus, the working device can easily be analyzed by using pivot information of links. The developed program also included a kinematic/static analysis module and characteristic analysis algorithms. Therefore, it is possible to easily analyze a working device model created through the automatic assembly algorithm, whereby users can easily analyze the effect of each link pivot point for the actual product design.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1353-1356
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• 2004

In recent year, OLED(organic light emitted display) is used as the next generation device of FPD. OLED have been replacing the flat panel display device such as LCD, STN-LCD and TFT because this device is more efficient, economic and simple than those FPD devices, and this need not backlight system for visualization. The performance and efficiency of OLED is related with surface defect of ITO coated glass substrate. The typical surface defect of glass substrate is nonuniformity and bad surface roughness. ITO coated glass substrate is destroied for inspection about surface roughness and non-uniformity. Generally detection of the defects in the surface for ITO coated glass substrate is dependent on operator's experience. In this research, relationship between working parameter and surface non-uniformity is studied using regression analysis.

• 한국안전학회지
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• 제26권4호
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• pp.14-19
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• 2011

Conveyors cause a high serious and fatal injuries in the industry. Every year people are hurt or killed as a result of accidents on conveyors. Most accidents occur during operation and maintenance when employees are working on moving, unguarded conveyors or when the conveyors starts unexpectedly. In 2008 there were 486 reported injures ranging from fatalities to injures. Of these 486 reported accidents, 8 were fatalities, 66.9%(325) of reported accidents occurred in manufacturing company and 43.8%(213) occurred at the belt conveyors. The objective of this study was to invent the remote emergency stop device because industrial accidents mainly occur at blind spots where usually do not have any safety guard or device rather than the normal working places. In principle, this new device will use with the existing safety system. Then, it will be powerful safety system for preventing injuries related with conveyors.

• 한국농공학회논문집
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• 제62권1호
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• pp.71-81
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• 2020

Enclosed pig house are creating an environment with high concentrations of gas and dust. Poor conditions in pig farms reduce pig weight and increase disease and accidents for livestock workers. In the pig house, the high concentration of harmful gas may cause asphyxiation accidents to workers and chronic respiratory disease by long-term exposure. As pig farm workers have been aging and feminized, the damage to the health of the harsh environment is getting serious, and real-time monitoring is needed to prevent the damage. However, most of the measuring devices related to humidity, harmful gas, and fine dust except temperature sensors are exposed to high concentrations of gas and dust inside pig house and are difficult to withstand for a long time. The purpose of this study is to develop an wearable based device to monitor the hazardous environment exposed to workers working in pig farms. Based on the field monitoring and previous researches, the measurement range and basic specifications of the equipment were selected, and wearable based device was designed in terms of utilization, economic efficiency, size and communication performance. Selected H₂S and NH₃ sensors showed the average error of 5.3% comparing to standard gas concentrations. The measured data can be used to manage the working environment according to the worker's location and to obtain basic data for work safety warning.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제37회 하계학술대회 초록집
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• pp.122-122
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• 2009

• 로봇학회논문지
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• 제17권2호
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• pp.191-197
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• 2022

In this research, we developed the muscle-strength-assistant device, named as LEXO-W, and conducted suitability test for army when transporting high weights. LEXO-W relieves the burden when carrying heavy weights by distributing the load concentrated on the arms throughout the body. LEXO-W weighs 4 kg and is designed to handle objects weighing up to 55 kg. To verify the effectiveness of the device, object handling tests (high explosive shell, simple assembly bridges, and ammunition boxes) were conducted. Working time, metabolic rate, and electromyogram (EMG) signals were measured in each test. As a result, it was confirmed that the working time, metabolic rate and EMG signal before and after wearing LEXO-W were decreased. This research has great significance in that it verified the performance of the wearable device from the perspective of military operation.

• 산업기술연구
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• 제21권A호
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• pp.213-219
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• 2001

This paper describes the power line proximity warning device for mobile crane by using the induced voltage measurement method. A mobile crane worker can be easily exposed to dangerous electrical shock and the electrocution while this are working at near the high-voltage electrical lines. In this paper, the derivation electric-potential of the power lines are simulated and microprocessor-based detecting device and transmitter/receiver modules are introduced to show a solution for the dangerous mobile crane working environment.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1995년도 춘계학술대회논문집
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• pp.155-164
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• 1995

For efficient operation, vital hand controls must be easily controlled by the operator from his normal working position. The primary working area based on operator's working comfort was developed to serve as a design guideline tothe control panel layout. Ten male subjects participated in the experiment in which working comfort was measured for two controls of a lever type control and a knob type control with respect to the frontal and sagittal distances from the body center and the slope of a workplace. The response surface methodolgy using a central composite design was employed to develop a prediction model for perceived working comfort of each control. Both controls have a similar pattern of comfortable working area, but the lever type control has slightly broader working area. The concept of the proposed working area is a significant extension to the conventional working area such as Farley's or Squires' curves. It is shown that the distance toa control device and the slope have a quadratic effect to working comfort. It is noticeable that comfortable working area exists outside the conventional working area. The result of the response surface analysis also indicated that a little slope of about 15 .deg. for a control panel improves working comfort.

• 한국화재소방학회논문지
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• 제27권1호
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• pp.14-19
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• 2013

본 논문은 소형 선박의 비상재난 발생 시 외부 VHF 장비와 연동하여 재난 상황을 자동으로 속보하는 기능을 수행하는 소형 선박용 재난자동속보장치에 대한 내용이다. 재난자동속보장치는 소형 선박의 재난 발생을 방지 또는 신속 대응하기 위한 시스템인 소형 선박재난분석시스템의 일부 장치에 해당하는 것으로서 선박재난분석시스템으로부터 재난 인지 신호와 GPS 위치 정보를 입력 받는다. 비상 상황 발생 시 위치 정보를 구조 요청의 음성 신호로 변환하여 외부 VHF 장비를 통해 송출한다. VHF 장비와 재난자동속보장치가 물에 잠기기 전까지 계속적인 음성 구조 신호를 송출할 수 있도록 한다. 본 연구를 통해 소형선박에 발생할 수 있는 갑작스런 재난상황의 대응과 인명손실을 예방할 수 있으리라 기대한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.288-290
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• 2006

An efficiency improving method for Uninterruptible Power Supply System(UPS) was developed by using OP-AMP based application circuits such as voltage detection device, current detection device and static switch control device. The efficiency improving algorithm was made by mixing the operating concepts of On-Line type UPS with the operating concepts of Off-Line type UPS. The UPS' inverter does not work if the UPS' output load current is not higher than the low load operating current which is about 0-30(%) of the UPS' output load capacity. The low load operating current is adjustable within the half of the UPS' output load capacity. If the UPS' output load current is rising over than the low load operating current, the UPS' inverter starts working and the inverter output power feeds to the loads of UPS. If UPS' input power breaks out while UPS' inverter does not operate because the load current is low, the inverter starts working within 4(ms) with excessive output voltage which is ${\pm}$8(%) of normal UPS' output voltage. Like these. UPS can continuously feeds power to it's load device and reduce power consumptions.