• Wind and Structures
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• 제8권4호
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• pp.295-307
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• 2005

The paper describes the work of the IAWE Working Group WBG - Reliability and Code Level, one of the International Codification Working Groups set up at ICWE10 in Copenhagen. The following topics are covered: sources of uncertainties in the design wind load, appropriate design target values for the exceedance probability of the design wind load for different structural classes with different consequences of a failure, yearly exceedance probability of the design wind speed and specification of the design aerodynamic coefficient for different design purposes. The recommendations from the working group are summarized at the end of the paper.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 2부
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• pp.73-75
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• 2011

Unlike other craft workers, construction craft workers perform their work under diverse working conditions, which means that their working pattern and postures continuously change. While construction craft workers are vulnerable to musculoskeletal disorders, due to the unique factors of their working conditions, their actual condition has not yet been accurately investigated. For this reason, this research aims to develop a method of measuring the musculoskeletal load of construction workers by reviewing various motion measuring methods to which state-of-the-art sensors are applied. This research is expected to serve as the basis for developing a system to measure the musculoskeletal load of construction workers.

• 한국농촌생활과학회지
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• 제8권2호
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• pp.111-117
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• 1997

In this study we tried to give a decision on propriety of working conditions, to present ideas on reducing work loads. and to grope for efficiency of agricultural works. For this we examined the actual conditions of working environment, farmer's clothes, working posture, working methods, working time, resting state, fatigue recovery methods during cultivating lettuce in the winter greenhouse. And Ive improved harmful factors that affect farmer's health by considering results of previous study and farmer's subjective sensation. And we measured, compared, and analyzed the farmer's work loads before and after improvement. The results of this study are as follows ; 1. According to examine the actual conditions of cultivating lettuce in the winter greenhouse, farmers have experienced physical and mental chronic fatigue on the basis of the hot and humid crops-centered working environment, the rough ground condition, inconsistent arrangement of working stand and sorter, heavy-weared habits. and unsuitable working posture. 2. When we improved harmful factors that affect farmer's health, conformed the positive effects on important work efficiency index such as heart rate, electromyovolume, body temperature, and microclimate inside clothing and work loads were decreased by improving the hot and humid working environment, eliminating the hillock and obstacles of working path. deliver way, arranging the working stand and sorter consistantly, decreasing the clothing weight, improving the working postures and methods as using assistant appliances, alloting the working time and sequence effectively and presenting the light gymnastic exercises and rest for fatigue restoration.

• Journal of Animal Science and Technology
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• 제44권2호
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• pp.261-270
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• 2002

본 연구에서는 한강유역에 위치한 축분퇴비공장의 작업환경 조사를 위한 현장 평가로서, 설문조사 및 악취물질 측정을 통해 근로자들의 작업환경 만족 수준과 이에 영향을 주는 요인들을 규명하였다. 연구결과, 축분퇴비공장 근로자들의 작업환경 만족도에 영향을 주는 요인들로 일반 건강수준, 악취, 작업량, 분진, 흡연으로 조사되었으며, 이 중 일반 건강수준, 악취, 작업량이 전체 작업환경 만족도의 61.3%를 대변하는 것으로 나타났다. 통계적 유의성을 나타낸 작업환경변수로는 일반 건강수준(p$<$0.01), 악취 작업량 분진(p$<$0.05) 등 이었다. 결론적으로 일반 건강수준이 높은 근로자일수록 작업환경 만족도가 높았으며, 작업량이 상대적으로 많고 악취와 분진에 쉽게 노출된 공장의 근로자일수록 작업환경 만족도가 낮은 것으로 분석되었다. 흡연을 하는 근로자는 작업환경 만족도가 낮게 나타냈으나, 통계적 유의성은 없는 것으로 분석되었다. 따라서 한강유역 축분퇴비공장 근로자들의 작업환경 만족도를 제고시키기 위해서는 공정 중 악취와 분진농도의 발생을 저감시켜야 할 것으로 판단된다. 그러므로 축분퇴비공장의 악취 및 분진농도의 발생을 최소화할 수 있는 처리공정 및 관리체계 정립이 시급하며, 이는 궁극적으로 축분퇴비공장 작업자의 건강 뿐만 아니라 주변 마을 정주민의 생활환경개선효과를 유발할 수 있다.

• 한국해양공학회지
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• 제12권3호통권29호
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• pp.9-18
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• 1998

An improved evaluation method of load-carrying capacity for the large-scaled offshore structures, which subjected to the axial force and bending moments simultaneously at the piles, was suggested with reliability analysis and advanced working stress method. Reliability analysis requires the fracture probability and safety factor(${beta}$) for each of forces and the load-carrying capacity due to combined action of axial force and bending moments from $P_n - {beta}$ Curve. The combined equation due to those forces, which suggested by the Korean Specification for the marine structure, was derived for the advanced working stress method and applied to evaluate the load-carrying capacity of jacket-type dolphin piers.

• 감성과학
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• 제25권2호
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• pp.11-22
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• 2022

사회적인 존재로서 우리는 다른 사람의 행위를 빠르고 정확히 이해할 필요가 있다. 행위 이해는 여러 수준에서 일어난다. 무심코 타인의 의도를 알아챌 때가 있는가 하면, 그들의 목적을 추론하기 위해 노력해야만 하는 경우도 있다. 결합 사이먼 효과는 과제를 분업하는 한 쌍의 참가자가 의도치 않게 동료의 행위를 표상할 수 있음을 실험적으로 증명한다. 이 효과는 거의 자동적으로 발생한다고 알려졌지만, 인지부하의 영향을 받지 않을 만큼 자동적인지는 확인되지 않았다. 이에 본 연구는 참가자에게 작업기억 부하가 있거나 없는 상태에서 결합 사이먼 과제를 수행하게 하였다. 이중과제 구획에서 저부하 집단의 참가자들은 한 개의 숫자를 작업기억에 유지한 채로 사이먼 과제를 분업하였고, 고부하 집단의 참가자들은 다섯 개의 숫자를 유지한 채로 사이먼 과제를 분업하였다. 작업기억 부하의 효과를 분석하기 위해 이중과제 구획과 단일과제 구획의 집단별 사이먼 효과를 비교하였다. 반응시간을 분석한 결과, 저부하 집단은 이중과제와 단일과제 구획에서 모두 사이먼 효과를 보였지만, 고부하 집단은 어느 과제 구획에서도 사이먼 효과를 보이지 않았다. 이 결과는 결합 사이먼 효과가 인지 자원에 의존한다는 면에서 자동적인 현상을 아님을 의미한다. 즉, 분업 참여자는 인지적 자원이 가용한 경우에만 동료의 행위를 과제 표상에 반영하는 것으로 보인다.

• 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.

• 대한치과보철학회지
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• 제34권1호
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• pp.31-69
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• 1996

The purpose of this investigation was to analyze stress distribution in implant supporting tissue according to different types of attachments such as combination bar attachment, Hader bar attachment, O-Ring attachment and Dal-Ro attachment that are used in mandibular overdenture by using two osseointegrated implants, to study the influence that POM IMC used in bar type attachment has in implant supporting tissue and compare the preceding analyses to find out an effective stress distribution method. Three dimensional photoelastic method was used to obtain the following results. (A) Analysis of stress distribution according to attachment type 1. Under vertical load condition, compressive stress was seen at implant supporting area of working side on all the photoelastic models but in Hader bar attachment tensional stress was seen at distal upper area of implant supporting area. Relatively Hader bar and O-Ring attachment showed even stress distribution pattern. 2. Under vertical load condition, compressive stress at implant apex area and tensional stress at implant lateral supporting area were seen at nonworking side of all models. 3. Under $25^{\circ}$ lateral load condition, general compressive stress was seen at working side implant supporting area in most of the models, especially at distal upper supporting area higher compressive stress concentration was seen in combination bar attachment and tensional stress concentration, in Hader bar attachment. 4. Under $25^{\circ}$ lateral load condition, compressive stress at implant apex area and tensional stress at implant lateral supporting area were seen at nonworking side of all models, except O-Ring model which showed compressive stress only. (B) Influence of POM IMC to stress distribution in bar type attachment 5. Under vertical load condition, better stress distribution pattern was seen at working side of combination bar and Hader bar attachment model using POM IMC. 6. Under vertical load condition, stress value was increased at nonworking side of combination bar attachment model using POM IMC and tendency of increasing compression was seen at nonworking side of Hader bar attachment model using POM IMC. 7. Under $25^{\circ}$ lateral load condition, better stress distribution pattern was seen at working side of combination bar attachment model using POM IMC but tendency of increasing stress was seen on working side of Hader bar attachment model using POM IMC. 8. Under $25^{\circ}$ lateral load condition, stress reduction was seen at nonworking side of combination bar attachment model using POM IMC but tendency of increasing stress was seen at nonworking side of Hader bar attachment model using POM IMC.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 추계학술대회 논문집
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• pp.75-79
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• 2002

A hydraulic Excavator is applied for outdoor tasks in construction, agriculture and undersea etc. When a hydraulic Excavator works crane function tasks, most of disasters happen. In this study, In order to preventing these disasters, the safety equipment algorithm for crane working is developed, and the safety equipment algorithm for crane working is being developed. The proposed control algorithm(Zero Moment Point) is designed to avoid overload. The hydraulic excavator for crane function must work within a maximum limit of load. To accurately detect a working load, pressure sensors of boom, arm cylinder, and angle sensors of boom, arm and bucket joint are used.

• 한국유체기계학회 논문집
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• 제18권1호
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• pp.29-36
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• 2015

Recently, Stirling engines are emerging as a key device for power conversion of renewable energy or waste energy. This study develops a LTDSE(Low Temperature Differential Stirling Engine) using a water spray for higher heat transfer and performs load performance tests for various flow rates and temperatures of hot water spray for variable engine loads emulated by a mechanical friction device. Internal temperature and pressure, working frequency and inlet and outlet temperature of the supply water are measured. As a result, the increases in flow rate and temperature of hot water respectively enhance the power output, efficiency and the working frequency, while the increasing engine load leads to decreases in working frequency but increases in the pressure amplitude. Eventually, it is revealed there exists a maximum shaft power of the test engine.