2013년도 전자상거래 소비자피해 동향 조사

김두환 한국소비자원 2014 조사보고서 Vol.- No.-

상수도 정책 및 발전방향

김두환 환경보전협회 2008 환경정보 Vol.30 No.378

교량의 과하중 확률계산을 통한 상태평가 등급 산정방법에 대한 연구

김두환,유창욱 한국안전학회 2009 한국안전학회지 Vol.24 No.4

The importance of process for repair and reinforcement of the bridge is increasing because of the lack of the fatigue load and stress, a lowering of the bridge load carrying capacity owing to impact and oscillation, deterioration on cultivation periods of the bridge, etc. Typically the experimenter values the bridge load carrying capacity by the real rating factor and response modification factor in bridge load rating through static load test and dynamic load test. But the error occurred in reliability of response modification factor in bridge load rating according to experience of experimenter. so tests of connecting probability theory and valuation of the bridge recently. The study is to compute the real load carrying capacity of the bridge and the rating factor and response modification factor on grade of the bridge, and calculate the probability of over-loaded truck load from Weigh In Motion(WIM) Data in FORTRAN programming applying to Monte-Carlo Simulation. At the result of this study, it is acquired that the new grade is computed for the probability of over-loaded truck load and surface inspection. The A grade is over 1.95, B grade is 1.55〜1.94, C grade is 1.26〜1.54, D grade is 1.14〜1.25, E grade is under 1.13 of rating factor, respectively.

Reverse Engineering(逆分析)에 대한 法的 小考 - 입법연혁과 대상산업의 변천에 따른 고찰을 중심으로 -

김두환,문준우 한국경영법률학회 2008 經營法律 Vol.18 No.4

Reverse engineering is the process of discovering the technological principles of a device, object or system through analysis of its structure, function and operation. It often involves taking something (e.g. a mechanical device, electronic component, or software program) apart and analyzing its workings in detail, usually to try to make a new device or program that does the same thing without copying anything from the original. Despite the popularity of the concept of reverse engineering with sections of the engineering community, the legislative position restricts reverse engineering of hardware and makes reverse engineering of software legal only under very limited circumstances in Europe. In the US, slightly more freedom is available to reverse engineers, but great care is still needed to avoid infringement. It is widely accepted that copyright does not protect "ideas", but only "expression"; that is, the way in which those ideas are "expressed". This idea is carried through into similar rights, such as Topography Rights. Copyright subsists in "copyright works". Reproduction or translation of the whole or a substantial part of a copyright work will constitute an infringement of copyright. Top level specification are themselves copyright works, and intermediate level specifications (source code and circuit diagrams) and lower level specifications (assembly code, net lists and node lists) may also qualify as copyright works. A common assumption is that the top level of a design specification is unprotectable by copyright, since it consists only of "ideas". Some assume that this applies also to some lower levels insofar as they cover "algorithms" and not actual code. On this assumption, "clean-room" reverse engineering techniques succeed in breaking the chain of copying, since if only unprotectable ideas are communicated to the new design team by the reverse engineers, the new design team cannot be copying protectable "expression". However, this approach is incomplete. Firstly, it ignores the fact that the intermediate copies made during reverse engineering are themselves infringements. Secondly, modern engineering tools can directly accept some high-level specifications, which are thus akin to executable code rather than abstract description.

鎔接 構造用 鋼材의 破壞靭性 特性에 關한 硏究

金斗煥 서울産業大學校 1988 논문집 Vol.27 No.1

龜裂先端 塑性區域이 너무 큰 경우 즉 大規模 降伏區域인 경우 龜裂先端의 應力 및 變形率 狀態를 說明할 수 있는 媒介變數로 J積分을 使用하여 龜裂先端을 包含하는 HRR 應力變形率場에서의 特異性을 나타낸다. 이 J積分 값은 彈塑性 破壞靭性値를 代表하고 있지만 龜裂이 成長한 以後에도 安定 龜裂成長이 發生하면서 荷重 支持部가 減少하여도 破壞抵抗은 增加하므로 龜裂進展點 以後를 規明하는 것은 相當히 重要한 問題이다. 本 硏究는 이러한 點을 考慮하여 平面應力狀態라 할 수 있는 鎔接殘溜應力이 內存된 SWS58 試驗片에 있어서 破壞靭性値에 미치는 殘溜應力과 龜裂比의 影響 및 各 J積分式에 따른 破壞靭性 擧動을 檢討하였다. 그 結果 두께가 一定한 試片의 破壞는 初期龜裂比가 큰 경우는 작은 에너지를 包含하므로 낮은 J 값을 갖으며, 殘溜應力은 350℃나 500℃의 熱處理 狀態에서는 J값이 크게 緩和되지 는 못하였으나 650℃나 800℃에서는 鋼이 塑性變形하여 거의 除去되나 800℃는 材質이 되므로 A₁變態溫度 以下가 바람직함을 알 수 있고 또한 Rice等에 依해 提案된 式은 다른 式들에 比해 過小 評價되므로 약간의 Merkle과 Corten 式은 거의 같은 性向을 보임을 알 수 있었다. In a case that plastic region of crack tip is very large, that is, large scale yielding zone, J-Integral as a prameter which can explain stress and strain conditions of crack tip is used. It is also expressed the uniqueness including crack tip at Hutchinson-Rosengren-Rice stress strain. Though these J values represent elastic-plastic fracture toughness value, it is very important to examine after crack development because when stable crack growth is occured, load resistance part is diminished and fracture resistance is increased. In this paper, it is studied effects of residual stresses and crack ratios falled on fracture toughness value of SWS 58 specimen inclued welded redual stresses and investigated the behavior of fracture toughness according to the each J-Itergral equations. From the reaults, inacase that thickness of specimen is constant and initial crack ratio is large, Fracture is occured at smaller J values for including lower energy. The residual stresses on the vicinity of a welding point were relieved effectively at the temperature from 650˚C to 800˚C which steel is transformed plastic than from 350˚C to500˚C It is showed to appropriate below A? transfdrmed steel quality. And also equation of Rice is understimated compare with others, therefore it is necessary to modify some increasement, merkle and corten equations considered tension effects is showed nearly same property.

양돈장 관리시스템이 출하돈의 도체품질에 미치는 영향

김두환,서종태,Kim, D.H.,Seo, J.T. 한국축산환경학회 2009 축산시설환경학회지 Vol.15 No.1

본 연구결과는 출하돈의 도체품질 향상과 품질인증 프로그램 구축을 위한 자료로 활용하기 위하여 2년 동안 53개 농장에서 출하된 248,787두에 대한 도체평가 결과를 모돈수에 의한 경영규모, 육성비육돈 단계의 사육밀도, 수송시간, 출하시점, 비육돈 후기사료 급여비율 및 비육돈사 형태에 따라 도체등급과 PSE 발생율, 도체 근간지방 점수, 근내지방 점수, 피하지방 점수 및 육탄력성 점수에 미치는 영향을 분석한 결과이며 요약하면 다음과 같다. 1. 양돈장 경영규모는 도체등급에 영향을 미치며, 경영규모가 커질수록 좋은 등급을 나타내었으나, PSE 출현율은 경영규모에 따른 차이가 인정되지 않았다. 도체 근간지방 점수, 근내지방 점수, 피하지방 점수 및 육탄력성 점수는 양돈장 경영규모에 따라 일정한 차이를 나타내지 않았다. 2. 육성비육돈사 사육밀도는 도체등급에 영향을 미치며, 중간 밀도에서 좋은 등급을 나타내었으나, PSE 발생율은 낮은 밀도에서 오히려 높게 나타났다. 도체 근간지방 점수와 근내지방 점수 및 육탄력성 점수는 중간 밀도에서 우수하게 나타났으나 피하지방 점수는 사육밀도에 의한 차이가 없었다. 3. 출하돈의 수송시간에 의한 도체등급 차이는 인정되지 않았으며, PSE 발생율 역시 수송시간에 의한 차이는 없었다. 그러나 수송시간은 도체 육질점수에 영향을 미치며, 1시간을 초과한 수송이 근간지방 점수와 근내지방 점수, 피하지방 점수 및 육탄력성 점수 모두 우수한 것으로 나타났다. 4. 출하시점은 출하후 계류를 통한 도축전 휴식과 관련되는데, 출하시점은 도체등급과 PSE 발생율에 영향을 미치지 않는 것으로 나타났다. 도체 근간지방 점수, 근내지방 점수 및 육탄력성 점수는 오전 10시 이전 출하가 우수한 것으로 나타났으나, 피하지방 점수는 차이가 없었다. 5. 비육돈 후기사료 급여비율 차이에 의한 도체등급 차이는 인정되지 않았으나, PSE 발생율은 후기사료 21% 이상 급여가 높은 것으로 나타났다. 도체 근간지방 점수와 근내지방 점수는 후기사료를 21% 이상 급여한 경우가 우수하게 나타났으며, 피하지방 점수는 후기사료를 20% 이내 급여가 우수하였으나, 육탄력성 점수는 비육후기사료 급여비율에 의한 차이는 인정되지 않았다. 6. 비육돈사 형태에 따른 도체등급의 차이는 무창돈사가 우수하게 나타났으나, PSE 발생율 또한 무창돈사가 높았다. 도체 근간지방 점수와 근내지방 점수는 비육돈사 형태에 의한 차이는 없었으나, 피하지방 점수와 육탄력성 점수는 개방돈사가 우수한 것으로 나타났다. 이상의 결과를 종합해 보면, 양돈장 관리시스템 및 도축전 취급이 출하돈의 도체등급과 육질점수에 영향을 미치는 구체적인 내용들을 확인할 수 있었다. 따라서 양돈장 관리시스템과 관련된 각종 환경요인과 관리요인 및 도축전 취급과 관련된 인자들에 대한 세심한 관리를 통하여 스트레스 최소화와 동물복지 향상으로 도체품질 개선과 소비자를 위한 품질인증 시스템을 구축하여야 할 것으로 사료된다. The purpose of this study was to investigate the effects of on-farm management systems(including the farm size, stocking density of growing-finishing phase, proportion of finisher diet and type of growing-finishing building) and pre-slaughter handling(including the transportation time and loading time) on carcass grade, the incidence of PSE pork, the meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and score for elasticity of market pigs. For this study, 248,787 pigs of 53 different farms were used to establish the pork quality assurance program and to meet the comsumer's need. The results are summarized as follows. 1. The farm size had significant influence on carcass grade, in which showing the higher grade by increasing the farm size. However, the incidence of PSE pork were not significantly differences among the farm size. The meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and score for elasticity of market pigs were not significant influenced by farm size. 2. The stocking density of growing-finishing phase was statistically significant for carcass grade, in which showing the higher grade in mid density group. However, the incidence of PSE pork was higher in high density group. The meat quality score for intra-muscle fat, inter-muscle fat and elasticity of market pigs were greater in mid density groups, but not influenced by stocking density for subcutaneous fat score. 3. The carcass grade and the incidence of PSE pork were not significantly influenced by transportation time. However, transportation time significantly affected the meat quality score, the meat quality score for intra-muscle fat, inter-muscle fat, subcutaneous fat and elasticity of the carcasses were superior in more than 1 hour transportation groups. 4. At any time loading, the carcass grade and PSE incidence were not significantly differences. However, the meat quality score for intra-muscle fat, inter-muscle fat and elasticity of market pigs were superior in before 10 AM groups, but not influenced by loading time for subcutaneous fat score. 5. The proportion of finisher diet had not significant influence on carcass grade, but PSE incidence affected by proportion of finisher diet, 21 percent or more group was higher PSE incidence. The meat quality score for intra-muscle fat and inter-muscle fat of the carcasses were superior in 21 percent or more fed finisher diet groups, but elasticity score of carcass had not influenced by the proportion of finisher diet. 6. The type of growing-finishing building was affected the carcass grade and PSE incidence of the market pigs, carcass grade and PSE incidence were superior in enclosed mechanical ventilation building groups. The meat quality score for intra-muscle fat and inter-muscle fat of the carcasses were not significantly differences by the type of finishing building, but the score of subcutaneous fat and elasticity of carcass were superior in opened natural ventilation building groups. In conclusion, the results of this study suggest that we have more precise on-farm management practice and the knowledge related to pre-slaughter handling skills to reduce the stress and improve the status of welfare of market pigs.

Preparation and Characterization of Organic-inorganic Hybrid Composite Film with Plate-shaped Alumina by Electrophoretic Deposition as a Function of Aging Time of Sol-Gel Binder

김두환,박희정,최진섭,임형미 한국세라믹학회 2015 한국세라믹학회지 Vol.52 No.5

Sol-gel binder was prepared by hydrolysis and condensation reaction using boehmite sol and methyltrimethoxysilane as a function of aging-time. The coating slurry was composed of a plate-shape alumina in the sol-gel binder for the EPD process, in which particles dispersed in the slurry were deposited on the electrode under an electric field due to the surface charge. We studied the effects of three parameters: the content of boehmite, the aging time, and the applied voltage, on the physical, thermal, and electrical properties of the hybrid composite films by EPD. The amount of boehmite was 10 ~ 20 wt% and the aging time was 0.5 ~ 72 , with a fixed amount of plate-shape alumina of 10 wt%. The condition of applied voltage was 5 ~ 30 V with a distance of 2 cm between the electrode during the EPD process. We confirmed that a structure of hybrid composite films of well-ordered plate alumina was deposited on the substrate when the film was prepared using a sol-gel binder composed of 15 wt% boehmite with 1 hr aging time and EPD at 10 V. The process shows a weight loss of 7% at 500oC in TGA and a breakdown voltage of 8 kV at 87 μm.

Parent Involvement in School, Teachers’ Perception of Students’ Academic Efforts and Students’ Academic Achievement in Korea

김두환,황여정 한국사회학회 2012 韓國社會學 Vol.46 No.3

This study examines the association between parent-teacher relation and students’ academic achievement in Korea. We analyzed the structural relationship among family SES, parent involvement in school, teachers’ perception of students’ academic efforts and students’academic performance by employing structural equation modeling. Using data from the 2005Korean Education Longitudinal Study, we explore the role of parent involvement in school in shaping parent-teacher relation and teacher-student relation in association with students’academic achievement. The results indicate that parent involvement in school has only indirect association with students’ academic performance through teacher-related variables. We discussed the results along with prior literature and suggested implication for educational policy in Korean context.

Effects of Intraday Patterns on a Time Series Analysis of the Korean Stock Market Index

김두환,맹성은,방유식,최형욱,차문용,이재우 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.2

The effects of intraday patterns were considered in a time series analysis of the Korean stock market. One minute tick data from January 2, 2004, to October 30, 2009, on the Korea composite stock price index were studied. The autocorrelation function (ACF) of the absolute return and the probability distribution function (PDF) of returns were calculated by using a time series with the intraday patterns removed. Two methods of eliminating the intraday patterns are suggested: elimination from the index itself and from the absolute returns. The ACF of the absolute return showed a power law with an exponent that did not vary with the method used to eliminate the intraday patterns. Eliminating intraday patterns from the absolute return removed the periodicity of the ACF. However, the periodicity remained if intraday patterns were removed from the index itself. The PDF of returns showed a power law, but its exponents depended on the method of removing the intraday patterns.

북한 건설개발 제도·인프라 동향조사 - 2015년도 2/4분기 -

김두환,김미숙,최상희,최대식,지은주 LH 토지주택연구원 2015 북한 건설·개발 동향 Vol.2015 No.2