• Nuclear Engineering and Technology
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• 제53권3호
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• pp.974-987
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• 2021

This paper presents ductile fracture simulation of full-scale cracked pipe for nuclear piping materials using the cohesive zone model (CZM). The main objective of this study is to investigate the applicability of CZM to predict ductile fracture of cracked pipes with various crack shapes and under quasi-static/dynamic loadings. The transferability of the traction-separation (T-S) curve from a small-scale specimen to a full-scale pipe is demonstrated by simulating small- and full-scale tests. T-S curves are calibrated by comparing experimental data of compact tension specimens with finite element analysis results. The calibrated T-S curves are utilized to predict the fracture behavior of cracked pipes. Three types of full-scale pipe tests are considered: pipe with circumferential through-wall crack under quasistatic/dynamic loadings, and with 360° internal surface crack under quasi-static loading. Computational results using the calibrated T-S curves show a good agreement with experimental data, demonstrating the transferability of the T-S curves from small-scale specimen.

• 한국벤처창업학회:학술대회논문집
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• 한국벤처창업학회 2006년도 추계학술발표회
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• pp.275-299
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• 2006

This study aims at examining the early-stage financing scale for entrepreneur to build small & medium business. The data was collected from the DART (Data Analysis, Retrieval and Transfer System) of Korean Financial Supervisory Service(FSS) in the main. The results of this study show that small & medium business needs equipment & operation financing for about 37 months extent to reach Break-Even Point. The limitations of this study are data collections from registered firms on Korean FSS primarily and no showing about the early stage financing scale for building small & Medium Business concretely. Small & Medium business entrepreneur have to make a early stage finance plan according to a necessary equipment and operating cost in their business field for 37 months extent.

• 한국보건간호학회지
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• 제12권2호
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• pp.12-26
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• 1998

The occupational health problems are the major issue in the modern industrial society. Especially the small scale industries have many hazardous factors and not any occupational health programs in itself. Fortunately. the government-funded subsidiary program was developed and carried out in the past six years in our country. The purposes of this study were to find out the actual condition of the occupational health personnel's accomplishments for the government-funded subsidiary program for small scale industries and to provide basic data for setting up more developed subsidiary occupational health program. Data were collected through 6 kinds of service records review. These service records were written by 3 occupational health personnels were attached to the one subject center of KIHA. were undertaken during March to December, 1997. at 95 small scale industries which were applied the government-funded subsidiary occupational health program. Results were as follows 1. Concerning 95 small scale industries showed characteristics of a typical small scale industry. 2. A doctor visited in industries total 190 times per year, average 19 industries per month, twice per year and industry. A hygienist visited in industries total 378 times per year, average 38 industries per month, four times per year and industry. A nurse visited in industries total 477 times per year. average 47 industries per month, 5 times per year and industry. 3. 3 occupational health personnels accomplished total 3,869 items. A doctor accomplished total 539 items per year, each time 3 items In an industry. A hygienist accomplished total 1.581 items per year, each time 4 items in an industry. A nurse accomplished total 1.749 items per year, each time 4 items in an industry. 4. The major contents of doctor's accomplishment were 'health consultation for suspicious worker with general & occupational disease', 'a check of the workplace & special health education', 'guidance of special medical examination in the second half of year', etc. The major contents of hygienist's accomplishment were 'pretest & guidance of planning for evaluation of working environment'. 'evaluation for ventilating facilities & suporting self inspection', 'guidance of MSDS recording & chemicals management', etc. The major contents of nurse's accamplishment were 'health counseling of general & special medical examination results'. 'health education of preventing occupational disease & health disorder'. 'guidance of subsidiary program planning', 'selecting & guidance of health monitor', etc. It was concluded that the occupaional health personnels implemented the subsidiary program according to the order of health management guide. The current health management guide of subsidiary occupational health program in which the fixed contents, visiting number & periods is not desirable. That guide is left the characteristics of small scale industries out of consideration. It is suggested that occupational health management guide should be developed according to the general & environmental characteristics of each small scale industry, and on the other hand, the more specific guide for each occupational health personnel should be developed.

• 수산경영론집
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• 제27권2호
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• pp.51-63
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• 1996

This study is concerned with the identification of the concepts and characteristics of the traditional access of small scale fishery and traditional small scale fishery based on the classification of fisheries under Fisheries Law, As we called, these fisheries are the small scale of artisanal fisheries. These traditional small scale of artisanal fisheries have been developed throughout the most coastal fisheries but have never been included the institutional fishery system and policy since industrial fisheries have been exploited. By this reason there was no studies to understand and identify these fisheries as fisheries under category of institutional fishery system. Recently by the Fisheries Law, my Person who desires to operate these fisheries, shall report to the provincial governor and then these fisheries were incorporated into the category of fisheries to be reported. But this case of the administrative practices should be not consistent with the classification of fisheries under Fisheries Law. The traditional access of small scale fishery is a derivative concept of fishery categories under the institutional fakery system Because this fishery under institutional fishery system can not be establish the right of fishing by fishery right system technically but the right of fishing is supported by the fishing access system only. Therefore, It is a mistake for the provincial fishery governor to adopt such a policy that the fishing right of the traditional access of small scale fishery which is different from the fishing based right is restricted by the factors of fisheries to be reported. On the other hand the traditional small scale fishery is coincident with the traditional access of small scale fishery and the common fishery under the style of utilization of fishing gear and fishing gear and methods. But this fishery has never been included the fishery categories supported by the government subsidy policies and considerations and has been remained with indifference during the last few decades. Anyhow the fishing right of these fisheries have been assured under the institutional fishery system, any person who desires to operate this fishery should have a fishing right against the public or private uses of fishing ground such as land reclamations and other coastal zone development. A deprivation of the fishing right of this fishery by the conflicts of these public and private uses of fishing ground is not regarded as appropriate according to the social welfare policy. Also it is the administrative expediency to support the fishing right of this fishery under the fisheries lobe reported.

• 한국유기농업학회지
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• 제27권4호
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• pp.437-452
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• 2019

소규모 식육포장처리장은 일반규모 작업장에 비해 종업원의 숫자가 적기 때문에 전반적인 위생상태 개선 및 HACCP System의 적용을 위해서 일반 규모 작업장에 비해 간단히 적용할 수 있도록 해야 할 필요가 있는 것은 사실이다. 하지만 여전히 축산식품 안전사고가 많이 나타나고 있는 시점에 국민건강 안전을 위해서라도 식육포장처리장에서 많이 발생하는 문제점, 그리고 그 위해의 심각도가 커서 사회·경제적으로 파급 여파가 큰 중요 관리항목에 대해서는 규모가 작은 업소에서도 철저히 준수해야 할 필요가 있다고 판단되며, 이는 HACCP 심사에도 연계하여 그에 대한 평가를 진행할 필요가 있다고 사료된다. 본 연구결과 도출을 위해 지난 3년간의 HACCP 심사 시 지적사항 발생빈도를 분석하고, 기존 논문자료 등을 참고하여 중요도를 결정하여 새로운 소규모 HACCP 평가항목을 도출하였다. 다만, 본 연구에서 개발된 소규모 식육포장처리업 HACCP 평가항목은 통계적, 문헌적 자료를 검토하여 도출한 것으로 실제 소규모 식육포장처리장 작업 현장에서 꼭 평가가 필요한 항목인지에 대해서는 추후 현장적용을 통해 추가적인 검토가 필요할 것으로 사료되고, 현행 『식품 및 축산물 안전관리인증기준』 고시에 따른 일반규모 축산물 HACCP 평가는 업종별 특성에 맞추어 평가항목이 다르게 적용되어 있으나, 소규모의 경우에는 식육판매업 및 식용란수집 판매업을 제외한 다른 업종은 전부 동일한 평가표를 이용하여 평가를 하도록 되어 있어 해당 업종의 특성에 맞도록 평가항목을 분리하는 등의 연구도 필요할 것으로 판단된다. 아울러 인력 부족 등으로 인하여 소규모 식육포장처리장에서 쉽게 적용하기 어려운 위해분석 등 HACCP 관리 평가항목에 대해서는 정부에서 쉽게 적용할 수 있는 모델 개발 등을 통해 소규모 식육포장처리장에서 무리 없이 HACCP을 적용할 수 있도록 유도하는 것이 중요한 것으로 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.134-135
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• 2003

Abstract in case of the small scale power system separated from large scale power system N-2 contingency, the Over excitation, Under Frequency and Power swing Tripping Relay operate depending on unbalance Of Generation and Load. and then we studied and measured the angle and frequency deviation between generators. moreover, we compared real fault example with simulation results.

• 한국환경과학회지
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• 제17권9호
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• pp.981-992
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• 2008

This study examined how to produce new methods of copper (II) sulfate crystallization by using a small-scale chemistry tool such as small-scale reaction surface and petri dish. The making of copper(II) sulfate is included in the 5th grade elementary science textbooks. Various copper(II) compounds were reacted with a 2 M sulfuric acid solution. The result of this study is as follows: Seven small amounts of copper(II) compounds were reacted with a few drops of 2 M sulfuric acid solution at room temperature to make a copper(II) sulfate crystal of triclinic shape. Using the petri dish method, a copper(II) sulfate crystal could be identified within one hour of reacting copper(II) hydroxide, copper(II) carbonate, copper(II) nitrate, copper(II) perchlorate, cupric(II) formate from a few drops of 2 M sulfuric acid solution at room temperature. When using the lap top method for copper(II) perchlorate, cupric formate, a proper crystal could be identified within one hour as well. SSC methods were used for the first time to make a copper sulfate crystal via chemical reaction. We can make a copper(II) sulfate crystal using a simple method which is easier, safer and saves time in class. And since a small quantity of chemicals are being used in SSC chemical methods, waste is greatly reduced. This lessens the amount of environmental problems caused by the experiment. This can be helpful in preserving nature. In addition the cost of chemical and laboratory equipment is greatly reduced because it uses material that we find in our daily lives. There will be continued study of small-scale methods such as improvement of new programs, study and training of teachers, and securing SSC tools. I would like to suggest such as SSC methods are applicable in elementary School Science. I would like it to become a wide spread program.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.1905-1913
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• 2011

The dynamic characteristic of bogie that is driving system of railway vehicle is very important regarding decision of vehicle characteristics as running safety and comport. The dynamic characteristic test of bogie is tested on full size in place on field testing on track. But, the testing on the full size caused many problems. To overcome these problem by full size test, the Railway Safety Research Center in Seoul National University of Science & Technology developed 1/5 scale size of small scale derailment simulator and is currently testing running stability of 1/5 scaled bogie. Also To take effectively advantage of running stability test using small scale derailment simulator in actuality design and reliability estimation, it is necessary comparison and examination with field test and theoretical analysis result In this paper. to achieve running stability analysis of 1/5 scaled bogie on small scale derailment. the program using MATLAB that is fast compose and analysis the motion equation of Saemaul power bogie is developed. It is achieved analysis according to various specification (weight, size, suspension, etc..) and is evaluated corelation between test result and dynamic characteristic of actual railway vehicle.

• 콘크리트학회지
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• 제3권4호
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• pp.133-142
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• 1991

원형(prototype) 철근콘크리트 구조물의 거동을 축소모형실험을 이용하여 연구하기 위해서는 모든 구성재료의 물리적 성질들이 특정상사(similitude)관계 또는 1:1로 복제된 모형재료를 사용하여야 한다. 원형과 모형의 물리적 특성에 관한 상사성에 대해 사전 연구가 되어져야만 축소모형실험결과 해석에 적용할 수 있다. 본 연구는 철근콘크리트 구조물을 축소모형화하는데 따른 구성재료의 물리적 성질과 기본 거동에 관한 문제점들을 파악하고, 개선된 방법을 찾기 위한 것이다. 모형콘크리트에서 발견되는 큰 인장강도를 최소화하기 위해 배합비를 변화시켜서 원형콘크리트에 가장 가까운 모형콘크리트의 제작기법과 모형철근의 표면형태에 따른 거동의 차이를 단순보를 이용하여 연구하였다.

• Earthquakes and Structures
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• 제18권3호
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• pp.337-348
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• 2020

Experimental testing has been considered as one of the most straightforward approaches to realize the structural behavior for earthquake engineering studies. Recently, novel and advanced experimental techniques, which combine numerical simulation with experimental testing, have been developed and applied to structural testing practically. However, researchers have to take the risk of damaging specimens or facilities during the process of developing and validating new experimental methods. In view of this, a small-scale structural laboratory has been designed and constructed in order to verify the effectiveness of newly developed experimental technique before it is applied to large-scale testing for safety concerns in this paper. Two orthogonal steel reaction walls and one steel T-slotted reaction floor are designed and analyzed. Accordingly, a large variety of experimental setups can be completed by installing servo-hydraulic actuators and fixtures depending on different research purposes. Meanwhile, a state-of-the-art digital controller and multiple real-time computation machines are allocated. The integration of hardware and software interfaces provides the feasibility and flexibility of developing novel experimental methods that used to be difficult to complete in conventional structural laboratories. A simple experimental demonstration is presented which utilizes part of the hardware and software in the small-scale structural laboratory. Finally, experimental layouts of future potential development and application are addressed and discussed, providing the practitioners with valuable reference for experimental earthquake engineering.