• 한국항해항만학회지
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• 제31권4호
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• pp.281-287
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• 2007

Human factors have been considered the primary reason of marine accidents. Especially, the collision between vessels is mostly mused by human behavior. However, there have not been many researches to clarify the reason of marine accidents mused by human factors quantitatively. In order to understand human factors and to enhance safe navigation systematically, using a full mission ship-handling simulator, we've investigated the characteristics of avoiding behavior taken by mariners. Further in order to apply the characteristics more widely and effectively, it's necessary to formulate the standard behavior for ship-handling in the condition of collision avoidance. Is this study, therefore, we intended to propose the concept to model the mariner's standard behavior on the handling of collision avoidance as the first step. As a result, we confirmed the contents of information processing in ship-handling that mariner's generally taking to avoid collision.

• Geomechanics and Engineering
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• 제34권6호
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• pp.597-609
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• 2023

One of the applicable methods for the stabilization of soil walls is the nailing system which consists of tensile struts. The stability and safety of soil nail wall systems are influenced by the geometrical parameters of the nailing system. Generally, the determination of nailing parameters in order to achieve optimal performance of the nailing system for the safety of soil walls is defined in the framework of optimization problems. Also, according to the various uncertainty in the mechanical parameters of soil structures, it is necessary to evaluate the reliability of the system as a probabilistic problem. In this paper, the optimal design of the nailing system is carried out in deterministic and probabilistic cases using meta-heuristic and reliability-based design optimization methods. The colliding body optimization algorithm and first-order reliability method are used for optimization and reliability analysis problems, respectively. The objective function is defined based on the total cost of nails and safety factors and reliability index are selected as constraints. The mechanical properties of the nailing system are selected as design variables and the mechanical properties of the soil are selected as random variables. The results show that the reliability of the optimally designed soil nail system is very sensitive to uncertainty in soil mechanical parameters. Also, the design results are affected by uncertainties in soil mechanical parameters due to the values of safety factors. Reliability-based design optimization results show that a nailing system can be designed for the expected level of reliability and failure probability.

• 한국의류학회지
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• 제30권9_10호
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• pp.1378-1388
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• 2006

We conducted a questionnaire survey of 481 Korean female college students and measured anthropometrically 2 girth of their bodies(bust, under bust girth) in order to understand the psychological needs about brassiere and the physical characteristics of consumers aged between 19 and 25(the 1924 generation). There were two major problems to be solved to improve the fit of brassiere in aspect of size. First, most brands for this age group aimed at product differentiation mainly on visual design not on brassiere size. According to the body measurements, the distribution of brassiere size had 6 sections '70AA, 70A, 70B, 75AA, 75A and 75B cups' showing a rate of 63.8% but most brands for this age group were producing '75A, 80A, 85A, 75B, 80B and 85B cups' showing a rate of 24.7%. Second, most subjects of this survey didn't know their own breast size and the sizing system of brassiere which are necessary in order to select the proper brassiere size. And most subjects were wearing a bigger size brassiere than their own body size even though one was in the range of '75A, 80A, 85A, 75B, 80B and 85B'. It might be possible that the dimensions of brassiere products in the market and the sizes indicated on the labels do not correspond. For increasing the consumer satisfaction it is necessary to adjust the production rate of brassiere sizes and to develop ergonomic brassiere products with proper dimensions and shapes for each brassiere size.

• Nuclear Engineering and Technology
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• 제40권1호
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• pp.49-68
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• 2008

The purpose of this paper is to extensively review the condition monitoring (CM) techniques using empirical models in an effort to reduce or eliminate unexpected downtimes in general industry, and to illustrate the feasibility of applying them to the nuclear industry. CM provides on-time warnings of system states to enable the optimal scheduling of maintenance and, ultimately, plant uptime is maximized. Currently, most maintenance processes tend to be either reactive, or part of scheduled, or preventive maintenance. Such maintenance is being increasingly reported as a poor practice for two reasons: first, the component does not necessarily require maintenance, thus the maintenance cost is wasted, and secondly, failure catalysts are introduced into properly working components, which is worse. This paper first summarizes the technical aspects of CM including state estimation and state monitoring. The mathematical background of CM is mature enough even for commercial use in the nuclear industry. Considering the current computational capabilities of CM, its application is not limited by technical difficulties, but by a lack of desire on the part of industry to implement it. For practical applications in the nuclear industry, it may be more important to clarify and quantify the negative impact of unexpected outcomes or failures in CM than it is to investigate its advantages. In other words, while issues regarding accuracy have been targeted to date, the concerns regarding robustness should now be concentrated on. Standardizing the anticipated failures and the possibly harsh operating conditions, and then evaluating the impact of the proposed CM under those conditions may be necessary. In order to make the CM techniques practical for the nuclear industry in the future, it is recommended that a prototype CM system be applied to a secondary system in which most of the components are non-safety grade. Recently, many activities to enhance the safety and efficiency of the secondary system have been encouraged. With the application of CM to nuclear power plants, it is expected to increase profit while addressing safety and economic issues.

• 헤리티지:역사와 과학
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• 제50권2호
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• pp.62-79
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• 2017

중국에서 건축유산의 수리원칙은 1930년대 중국영조학사의 양사성이 처음으로 제시하였다. 이후 수리현황은 1950년대 새로운 사회적, 정치적 배경아래 다양한 건축 수리 경험을 토대로 1961년 "문물보호관리잠행조례"에 '원상회복 혹은 현상보존'으로 명시되었다. '원상회복 혹은 현상보존'에서 원상회복은 대체로 창건기 모습으로의 복원을 의미하는데, 20세기 초 중기에 한국과 일본에서도 당초모습으로 복원하는 원칙에 근거해 문화유산을 수리하는 경우가 많았기 때문에, 이 시기 동북아지역의 건축유산 수리에서 창건기 모습으로의 복원은 보편적이며 주도적인 원칙이었다고 볼 수 있다. 하지만 중국의 경우 원상회복과 함께 현상보존도 대등하게 명시되어 있는데, 당시의 주도적인 흐름을 생각할 때 이는 다소 의외로 보이기 때문에 그 형성과정과 의미에 궁금함이 생긴다. 처음으로 수리원칙을 제시하였던 양사성에 대한 연구는 매우 중요하지만, 중국에서 원칙과 관련된 국제이론에 대한 활발한 연구에 비해 양사성의 수리원칙에 대한 입체적 분석은 부족하다. 중국 수리원칙의 형성과정과 그 정확한 의미를 알려면 먼저 양사성이 제시한 보호원칙을 중점적으로 분석해야 하고, 그리고 그것이 중화인민공화국 건국 후 문화유산 보호를 둘러싼 사회적 배경속에서 어떻게 변화되었는지를 종합적으로 살펴보아야 한다. 이 글에서는 먼저 양사성이 문물의 원상에 중요한 가치를 둔 원상회복 위주의 수리원칙을 제시하고, 동시에 가치판단의 결과 혹은 현실적인 이유로 인한 현상보존의 가능성도 열어두었음을 살펴본다. 그리고 건국 이후 소련 건축유산 보호제도의 영향, 경제개발 위주의 정책으로 인해 현상보존이 하나의 현실적인 원칙으로서 원상회복과 대등하게 등장하는 과정을 살펴본다.

• 한국건설관리학회논문집
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• 제16권1호
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• pp.44-51
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• 2015

국내 건설경기는 주택경기 침체, 글로벌 금융위기 등의 영향으로 2008년부터 본격적인 침체가 최근까지도 지속되고 있으며, 장기화되고 있다. 이러한 어려움을 타파하기 위해 건설기업에서도 서비스기업과 같이 내부마케팅 활동을 강화시켜야 한다. 하지만 건설기업은 기존의 서비스기업과 달리 직접적으로 고객을 응대하지 않을 뿐 아니라 건설 현장이라는 특수한 상황에 처해 있어 적극적 내부마케팅 활동 강화가 쉽지 않은 상황이다. 따라서 내부마케팅 활동 중 우선순위를 선정하여 가장 시급한 부분부터 개선해 나아가야 한다. AHP 분석 결과 1계층에서 내부 의사소통이 가장 우선적으로 강화시켜야 할 요소로 나타났으며 그, 다음으로 근무조건 및 환경으로 나타났다. 그 다음 각각의 상위 개념별 하위 활동을 보면 내부 의사소통에서 상사와의 의사소통을, 근무조건에서는 일일 근무시간 전반적 만족을, 보상 및 포상에서는 수주 기여 시 보상으로 나타났다. 교육훈련에서는 전문가들의 의견 일치를 보지 못하였다.

• 한국응급구조학회지
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• 제11권3호
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• pp.93-109
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• 2007

The pre-hospital care in site transportation care and site care will be divided, it will follow in site or evacuation it will enforce it will can evacuate in condition of the emergency patient of like this at the initial stage and emergency care from inside fire fighting helicopter back transfer means and the manpower security of the specialty emergency necessary personnel(nursing and 1st EMT's) as the medical treatment agency and modernization of first aid equipment necessity inside American securing and fire fighting helicopter and specialty first aid packet won about lower the emergency care which is appropriate cannot become accomplished are the actual condition in total lack of emergency care equipment. Consequently craving augmentation, in order to be adapted with the handling kind transfer whose specialty and is appropriate and present time of rapid increase and the citizen of emergency demand by fire fighting helicopter simplicity transfer compared to it is a condition where the countermeasure preparation is earnest. Must expand emergency care equipment first even in fire fighting helicopter and 1st EMT's which it follows in him become arrangement and quickly the execution and specialty temporary disposal(ALS) must be enforced a temporary disposal and must buy the life which is. Also it gets by experience a helicopter induction outline, a radio communication method and the patient helicopter on-board hour attention point back various attention fact back with the body and when where it stands but accurately there must be it will be able to induce the helicopter. Also every manuals anger it does a helicopter transfer method and the emergency care method back and that all processes must do fixed form anger, it becomes feed. Also it related with a helicopter transfer even from the relationship agency many research to lead, difference of the advanced foreign nation and the maximum it is the actual condition where the medical emergency system construction which it reduces is earnestly demanded. Also with emergency structure(crane) it confronts to an aviation transfer even from the establishment college and education it leads intensively and 1st EMT's of the good quality which relates with an aviation structure expects is cultivate at all.

• 해양환경안전학회지
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• 제6권2호
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• pp.1-15
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• 2000

In world trade, the vessel traffic in major routes has been congested due to the rapid increase of cargoes and shipping tonnages. The patterns of vessel traffic have also been complicated and diversified. Therefore it was necessary that the Vessel Traffic Service(VTS) should be established in order to enhance the safety of navigation, to prevent the loss of life and damage to the environment. The first advanced radar surveillance system(LevelIII-VTS) was introduced in Pohang, Korea in 1993 and in 13 other ports later. While the hardware of Korea VTS is equal to that of an advanced country, the software, specially the operation manual, the recruitment and education of VTS operator, and the VTS service area is behind that of Russia, USA, Germany, Hong Kong, Singapore and others. After researching and investigating. the VTS equipment and service area of many countries, and analyzing the IMO regulations relevant to VTS and the traffic pattern and accident of Pohang port, the most efficient VTS service area should be established in Pohang. According to the analysis of the preceding studies and research on VTS, the worldwide VTS areas are recognized under the following conditions: First, the service area should be extended over at least radar coverage taking into account of traffic flow, traffic density, the degree of danger to navigation and harbour condition in order to provide all possible services. Second, the established service area should be subdivided and systematized to render reliable VTS services, such as the allocation of VHF frequency and reporting procedure in each area. In conclusion, the VTS service area of Pohang must be established and operated over 10 miles from shore(radar site) covering the radar coverage, so as to include the area of traffic congestion and high density traffic flow.

• 보존과학연구
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• 통권30호
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• pp.79-91
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• 2009

Stone cultural heritages are mostly situated in field, so they are damaged from mechanical, chemical and biological weathering, and their degree of strength is also weaken. Therefore, the scientific conservation of the stone cultural heritages are necessary in order to the long-term maintenance and safety conservation. In this study, we attempt to estimate on the field application of consolidants which are Wacker OH 100, Remmers KSE 300 and 1T1G according to the quality of the rocks. Based on the ultrasonic velocity, conditions of weathering damage before treatment are mainly ranked completely weathering condition (CW) or partly highly weathering condition (HW). After the first treatment, weathering damage conditions are changed by the high weathering condition (HW). These results shows that the internal pores of stone are filled with consolidant materials, so average ultrasonic velocities increases after treatment. And Remmers KSE 300 which is consolidant material is highest rate of increase of average ultrasonic velocities.

• 산업경영시스템학회지
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• 제39권4호
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• pp.7-14
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• 2016

Unlike most researches that focus on single manufacturer or single buyer, this research studies the cooperation policy for two participants of supply chain such as single vendor and single buyer. Especially, this paper deals with single vendor-single buyer integrated-production inventory problem. If the buyer orders products, then the vendor will start to make products and then the products will be shipped from the vendor to the buyer many times. The buyer is supposed to order again when the buyer's inventory level hits reorder point during the last shipment and this cycle keeps repeated. The buyer uses continuous review inventory policy and customer's demand is assumed to be probabilistic. The contribution of this paper is to present a mixed approach and derive its cost function. The existing policy assumes that the size of shipping batch from single vendor to single buyer is increasing, called Type 1, or constant, called Type 2. In mixed approach, the size of shipping batch is increasing at the beginning part of the cycle, and then its size is constant at the ending part of the cycle. The number of shipping for Type 1 and Type 2 in a cycle in mixed approach is determined to minimize total cost. The relationship between parameters, for example, the holding cost per product, the set up cost per order, and the shortage cost per item and decision variables such as order quantity, safety factor, the number of shipments, and shipment increasing factor is figured out via sensitivity analysis. Finally, it is statistically proved that the mixed approach is superior to the existing approaches.