• 정보보호학회논문지
• /
• 제16권5호
• /
• pp.113-118
• /
• 2006

가명을 이용한 시스템에서는 가명을 발급한 기관에게도 사용자의 익명성이 유지되어야 하며, 다만 정책적으로 사용자가 규칙을 어겼을 때는 가명으로부터 사용자의 신원정보를 추적할 수 있어야 한다. 이 논문에서는 m--out-of-n oblivious transfer와 cut-and-choose 기술을 이용하여 추적 가능한 가명 은닉 획득 프로토콜을 제안한다.

• 한국정보보호학회:학술대회논문집
• /
• 한국정보보호학회 1997년도 종합학술발표회논문집
• /
• pp.378-383
• /
• 1997

D. Chaum은 RSA암호알고리듬을 이용한 은닉서명방법으로 전자현금시스템을 제안했다. 그러나 이 방법은 사용자가 은행으로부터 전자현금을 발행받을 때 cut-and-choose방법을 사용함으로써 큰 통신부하(communication overhead)를 가지는 비효율적인 면이 있다. 본 논문은 제비뽑기방법을 이용하여 cut-and-choose방법을 사용하지 않고 사용자의 프라이버시를 보호하는 새로운 전자현금시스템을 제안한다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2006년도 추계 학술발표회
• /
• pp.46-55
• /
• 2006

There are many kinds of braced cut wall methods as the sheet pile, SCW, CIP and slurry wall which is adoptable for a deep excavation construction in a coastal filled land. The braced cut wall which has a strong stiffness is very stable but it has the weak point that the construction cost is high. Thus when a braced cut wall is designed, the geotechnical engineers choose the braced cut wall which has more safe and economic in the consideration of surrounding buildings near the construction site. Especially, when the sheet pile method as a braced cut wall is cheesed, the layer order and consistence of a coastal deposit stratum are considered and the pile driving method is also considered. This paper introduces the case that the originally box-type sheet pile wall was changed to U-type and high strength material after the pilot test at the subway construction site in a coastal filled land. This paper also introduces the case that the sheet pile's driving method was changed to special method in the section of the temporary coffer dam which had made when the present coastal filled land was formed.

• 응용통계연구
• /
• 제9권2호
• /
• pp.161-169
• /
• 1996

표본크기 결정은 표본설계시 중요한 부분이며 정도(Precision)를 높이면서 비용, 시간 등을 고려하여 최적화(Optimal)된 표본의 크기를 구하려 할 때 모집단 분포가 심한 왜도(highly skewed)를 보이거나 소수의 모집단요소들이 모집단총계의 대부분을 차지하는 경우가 있다. 이에 대해 Neyman의 최적할당법과 절사법(cut-off method) 응용 방법의 효율성을 사례를 이용하여 비교하였다.

• 한국강구조학회 논문집
• /
• 제9권3호통권32호
• /
• pp.457-465
• /
• 1997

형상최적화는 단면최적화에 비하여 구조물의 중량과 경비를 줄일 수 있다. 많은 양의 애매한 정보가 최적설계 문제의 제약조건에 존재할 수도 있다. 상대적으로 중요한 퍼지정도를 포함한 여러개의 기준을 묘사하고 다루는 것은 매우 어렵고 때로는 애매하다. 본 논문에서는 ${\alpha}$-절단법에 의한 퍼지 구조계의 다목적 형상최적화에 대한 가중치방법을 제안한다. 본 연구의 알고리즘을 2부재 트러스 구조물에 적응하여 그 결과가 검토되었다. 그 결과는 ${\alpha}$-절단법과 체적과 변위에 관한 가중치에 따른 최적해를 얻음으로써 설계자는 실제에 적합한 하나의 해를 택할 수 있음을 보여준다.

• 지역연구
• /
• 제14권1호
• /
• pp.109-126
• /
• 1998

We analysed the determinants of part-timer labor demand and supply in Kwangju. The findings of the paper are as follows; First, firms employ part-timer workers in the unskilled or skilled jobs not demanding much training cost. There are two reasons for firms to employ part-time workers: labor cost cut and flexible employment adjustment. Estimated wage differential is 40% not including fringe benefits differential. Second, we find lots of married women to want part-time jobs. The more probably married women choose part-time work, the younger and the less educated they are, and the less kids and the less other income they have.

• 정보보호학회논문지
• /
• 제17권4호
• /
• pp.75-88
• /
• 2007

현재의 전자투표 시스템은 투표자로 하여금 일방적인 신뢰를 강요하고 있으며, 투표자의 의도대로 기록되었음을 입증하지도 않는다. 전자투표가 종이투표 방식보다 많은 장점을 제공할 것이라고 기대하고 있음에도 불구하고 이러한 신뢰성 결여는 전자투표 실시를 막는 주요 요인이 되고 있다. 많은 전문가들은 투표자에게 투표기가 정확하게 동작하고 있음을 확신시키기 위해 영수증을 발급하는 방안을 긍정적으로 고려하고 있다. 본 논문에서는 이미 잘 알려진 cut-and-choose 방식을 응용한 영수증 발급 방식을 제안한다. 제안하는 방식은 특수한 영수증 출력 장치나 제삼자에 의한 투표기 검증 등이 필요없으며, 기존 방식보다 높은 안전성을 제공한다.

• 한국환경복원기술학회지
• /
• 제6권6호
• /
• pp.72-85
• /
• 2003

The purpose of this study is to establish the basis of the ecological restoration on the limestone mines in Korea, through the research of the revegetation measures of the disturbed slopes in Japanese limestone mines and the analysis of the case of Ibuki and Bukou limestone mines to realize the restoration works successfully. According to the number of mines to carry out the revegetation works increase every year, the revegetation area and amount of planting also go on increasing in Japan. In the small mines the environmental problem is not recognized seriously, but some mines have muchly invested in the revegetation of the damaged land by mines. Ibuki mine in Shiga-gen is practicing the four principles for the restoring of the revegetation in the disturbed slopes by mines. Firstly, the mean slope preserves $37^{\circ}$ in the last rock cut slopes. Secondly, the last rock cut slopes to rehabilitate are covered with the soil dressing 30cm high. Thirdly, the grasses in the mining area are digged up beforehand, and then they are reused to the revegetation works of rock cut slopes. Lastly, from the upper rock cut slopes the revegetation works begin, the process of the above are repeated, as the result, the restoring works will be completed. Upon the ground of these principles, the complex of the original vegetation and the native species seeding, that is, the revegetation technique of Ibuki have established. In the difficult area to revegetate, sodding works, heaping up vegetation-sack, seed-spraying, heaping up soil-sacks and planting works are adapted variously. Bukou mine in Saitama-gen try to maintain the revegetation, the screening and the stability of the enormous mining rock cut slope, and for these works, the activity of 'Chichibu Working Group of Rock Wall for Limestone Mines' contributes largely. The chief technique of the revegetation in Bukou mine is following; after the making the berm on the rock cut slopes, the soil dressing is filled in it, and the trees is planted for the screening of the rock cut slopes. They devide the rock cut slopes into four typical types, and choose the different ways to make the berm and fill the soil dressing in characteristic. Most of the planting trees are consist ofthe native species of Mt. Bukou through the stages of the nursery and transplantation. Not only the revegetation of the demaged land but also the breeding of the conservational plants also are their important business.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2002년도 추계학술대회 논문집
• /
• pp.192-197
• /
• 2002

In this study, examined the cutting characteristics of alumuminum alloy AC8A-T6 that is used to present car piston materials. And in been holding materials machining empirically escape as result that experiment comparison changing the cutting speed and feed on various condition to choose efficient machining condition. The following results can be summarized from this research. 1. As the cutting speed decreased, principal cutting force and thrust cutting force is increased, and reason that cutting force interacts greatly in the low cutting speed is thought by result by BUE's stabilization. 2. The feed speed and cutting speed increase, friction factor is decrescent and the cause appeared the thrust cutting force is fallen than cutting force relatively because chip flow according to increase of the feed rate is constraint. 3. Though specific cutting resistance grows cutting area and the feed rate are few, the cause was expose that shear angle decreases by rake face of tool gets into negative angle remarkably as wear of a cutting tool or defect part of workpiece is cut. 4. Cutting speed do greatly depth of cut is slow, surface roughness examined closely through an experiment that becomes bad, and know that it can get good surface that process cutting speed because do feed rate by 0.1mm/rev low more than 250m/min to get good surface roughness can.

• 한국축산식품학회지
• /
• 제37권5호
• /
• pp.682-689
• /
• 2017

The aim of this study was to investigate the digestibility of different Korean Hanwoo beef cuts using an in vitro digestion model, in vitro physicochemical upper gastrointestinal system (IPUGS). The four most commonly consumed cuts - tenderloin, sirloin, brisket and flank, and bottom round - were chosen for this study. Beef samples (75 g) were cooked and ingested into IPUGS, which was composed of mouth, esophagus, and stomach, thereby simulating the digestion conditions of humans. Digested samples were collected every 15 min for 4 h of simulation and their pH monitored. Samples were visualized under a scanning electron microscope (SEM) to examine changes in the smoothness of the surface after digestion. Analysis of the amino acid composition and molecular weight (MW) of peptides was performed using reverse-phase high performance liquid chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis, respectively. Following proteolysis by the gastric pepsin, beef proteins were digested into peptides. The amount of peptides with higher MW decreased over the course of digestion. SEM results revealed that the surface of the digested samples became visibly smoother. Total indispensable and dispensable amino acids were the highest for the bottom round cut prior to digestion simulation. However, the total amount of indispensable amino acids were maximum for the tenderloin cut after digestion. These results may provide guidelines for the elderly population to choose easily digestible meat cuts and products to improve their nutritional and health status.