교각형상에 따른 국부세굴에 관한 실험적 연구

이성대,이현국,신현길,이승훈 한라대학교 2007 論文集 Vol.10 No.-

For geotechnical and economical reasons, various bridge piers have become more and more popular in bridge design. This type of pier can significantly reduce construction costs, compared to spread footer structures when sediment scour is a consideration. However, the scour mechanisms for piles are much more complex, and design of local scour depths more difficult to predict. In this Experiments of local scour around the downward tapering oblong pier with the geometrically nonlinear structurea and a series circular piers are carried out under steady clear water scour conditions. The paper presents the following research results: The scour at a series circular piers is different from that around a single pile, depending on the pile spacing. The interference effect diminishes for pile spacing L_(d)/D=3.5, depending on the pile group arrangement.

작업의 특성에 종속되는 병렬기계의 일정계획을 위한 발견적 기법

이동현,이경근,김재균,박창권,장길상 한국경영과학회 2000 經營 科學 Vol.17 No.1

In the real world, situations that some jobs need be processed only on certain limited machines frequently occur due to the capacity restrictions of machines such as tools, fixtures, or material handing equipment in this paper, we consider n-job, non-preemptive and m parallel machines scheduling problem having two machines group The objective function is to minimize the sum of earliness and tardiness with different release times and due dates The problems is formulated as a mixed integer programming problem The problem is proved to be NP-complete Thus, a heuristic is developed to solve this problem To illustrate its suitability and efficiency, a proposed heuristic is compared with a genetic algorithm and tabu search for a large number of randomly generated test problems in ship engine assembly shop Through the experimental results, it is showed that the proposed algorithm yields good solutions efficiently

납기와 조립가능 시점을 고려한 병렬기계의 스케쥴링을 위한 발견적 해법

이동현,이경근,김재균,박창권,장길상 한국경영과학회 2000 한국경영과학회지 Vol.25 No.2

In this paper, we consider an n-job, non-preemptive and identical parallel machine scheduling problem of minimizing the sum of earliness and tardiness with different release times and due dates. In the real world, this problem is more realistic than the problems that release times equal to zero or due dates are common. The problem is proved to be NP-complete. Thus, a heuristic is developed to solve this problem. To illustrate its suitability, a proposed heuristic is compared with a genetic algorithm for a large number of randomly generated test problems. computational results show the effectiveness and efficiency of proposed heuristic. In summary, the proposed heuristic provides good solutions than genetic algorithm when the problem size is large.

레이온회사 퇴직근로자에서 이황화탄소에 의한 건강영향평가 : 직업병 인정여부에 따른 자각증상과 관련 요인 Subjective Symptoms and Related Factors According to Compensation for CS_2 Poisoning

이경재,김주자,최현림,양길승,김호,임상혁,이윤근 大韓産業醫學會 2003 대한직업환경의학회지 Vol.15 No.2

목적: 이 연구는 이황화탄소 취급 사업장에서 근무한 경력이 있는 퇴직 근로자들을 대상으로 이황화탄소에 의한 건강영향을 조사함으로써, 이황화탄소 노출 후의 건강영향 파악 및 이황화탄소 노출 근로자에 대한 건강관리 기준 마련 등에 중요한 기초자료를 제공하고자 하였다. 방법: 이 연구는 우리나라 모 레이온회사에 근무한 경력이 있는 퇴직 근로자 중에서 1998년 12월까지 직업병 여부를 확인하기 위해 건강진단을 신청한 1,702명 중에서 이미 사망한 40명을 제외한 1,662명을 대상으로 하여 이 연구 목적에 대한 설명문을 우편으로 발송하여 참여 의사를 밝힌 258명을 면접대상으로 하여 최종적으로 177명을 분석 대상으로 하였다. 결과: 연구대상자는 남자가 147명, 여자가 30명이었고, 평균 연령은 55.4세이고 입사시 연령은 29.1세였다. 근무부서별로는 고폭로부서에 근무한 군이 156명으로 88%를 차지하였으며, 인정받은 군이 103명(58.2%), 받지 못한 군이 74명(41.2%)이었다. 평균 총폭로지수는 38.96(±31.18)이었고, 인정받은 군에서 받지 못한 군 보다 유의하게 높았고 (p=0.000). 고폭로부서군에서 저폭로부서군보다 높게 나타났다(p=0.000). 퇴사전후 시간에 따른 호소 증상들을 분석한 결과, 퇴사전후 시간 흐름에 따라 호소하는 증상들이 차이는 있지만 호소하는 증상들이 퇴사전과 퇴사후 5년 이내에 비해 퇴사후 5~10년인 경우에는 인정받은 군과 받지 못한 군 간에 유의한 차이를 보이는 호소 증상들이 적어지는 경향을 보였다. 그러나 퇴사 10년 이상인 경우에는 퇴사후 5~10년 이내에 비해 오히려 호소하는 증상들은 많아진 반면, 인정받은 군보다 받지 못한 군에서 유의하게 높았다. 따라서 이는 퇴사후 10년 이상이 되면 그 이전 기간에 비해서 호소하는 증상들은 직업병 인정에 올바른 영향을 미치지 않을 수도 있다고 생각되고 이러한 결과에 영향을 미칠 수 있는 여러 가지 요인들을 생각해 볼 필요가 있다고 생각된다. 인정받은 군에 대해서 직업병 인정시점을 기준으로 인정전후에 호소 증상의 변화를 비교한 결과, 대부분 직업병 인정전에 비해 인정후에 호소하는 증상이 감소하는 경향을 보이고 있어 직업병 인정후에 의료기관으로부터 증상관리가 이루어지는 것이 증상호소를 줄이는 데 기여한 것으로 생각되며 이밖에도 직업병 인정으로 인한 심리적인 보상도 영향을 미칠 수 있을 것으로 생각된다. 직업병 인정여부에 영향을 주는 요인에 관하여 분석한 결과, 총폭로지수와 퇴사후 최종 건강진단을 받을 때까지의 시기가 유의한 요인으로 나타났으며, 퇴사후 직업병 인정을 받을 때까지의 시간에 대한 Cox의 비례위험 회귀분석을 한 결과, 총폭로지수와 입사연령, 고폭로부서의 근무여부가 의미있는 요인으로 나타났다. 결론: 이 연구를 통하여 이황화탄소 취급 사업장에서 근무한 퇴직 근로자들을 대상으로 직업병 인정에 따른 호소 증상을 분석하고 직업병 인정에 영향을 주는 요인을 분석해 봄으로써 이황화탄소 노출에 의한 건강영향을 파악하고 폭로 이후의 증상변화를 예측 관리할 수 있는 자료를 마련하고자 하였으며 이는 이황화탄소 노출 근로자들에 대한 건강관리에 기초자료로 의미를 가질 것으로 생각된다. Objectives: To investigate the chronological subjective symptoms and related factors in exworkers who were occupationally exposed to Carbon disulfide. Methods: One hundred and seventy-seven subjects(147 males and 30 females) were randomly selected among ex-workers and interviewed by well trained doctors, who filled out a structured questionnaire developed by authors on the subjective symptoms. The questionnaire was composed of symptoms in the head and neck, and those of the neuro-psychological, respiratory, endocrine, musculoskeletal, and reproductive systems. Other factors such as general and occupational characteristics including work department, work duration, duration since cessation of exposure, and compensation for occupational disease were also investigated. Results: The mean subject age was 55.4 years. The mean cumulative exposure index (CEI) was 38.96±31.18. CEI was significantly higher in the compensated group(47.61±32.51) than in the non-compensated group(26.81±24.75)(p=0.000). Symptom complaints were significantly higher in the compensated group in all organ systems, and their incidence increased gradually until 10 years after cessation of work, and then decreased. The mean duration for cessation of exposure at the time of compensation was 10.97 years. The significantly different factors between the compensated group and the non-compensated group were total cumulative exposure index and the time interval between the cessation of work and the time of compensation. Conclusion: Our findings suggest that total cumulative exposure index and the time interval between the cessation of work and the time of compensation may be important factors affecting the compensation for occupational disease. Therefore, further studies will be necessary.

내기밀 DCI 주물의 제조 기술에 관한 연구

이병엽,인현만,이의길 한밭대학교 산업과학기술연구소 1994 논문집 Vol.2 No.-

It is very important to control the chunk graphite, dross inclusions and pinholes in pressure tight DCI castings. In this study, it is attempted to obtain sound DCI castings without defects by process control and small anount of special additives. Obtained conclusions are as follow. Chunk graphite can be overcome by small additions of Ce as mishmetal…about 0.01∼0.03% and ruducing the nodule count in ductile iron. One of the best detterrents to pinhole porosity is to treat and pour at sufficiently high temperature so any hydrogen absorbed by iron has a chance to get out before casting solidifies. Te additions of 0.01% of iron are helpful in reducing or elimination the pinholes. A moderately pressurized gyting system having a spure, runner, ingate ratio of approximately 4:8:3 or 2:4:1 has consistently produced quality castings in all size rages.

複合的商業스포츠施設의 利用實態와 運營實際上의 問題點과 課題 : 大邱市 地域을 中心으로

李來華,金永煥,申榮吉,李秀川,朴炫權 慶北大學校 體育科學硏究所 1991 체육과학연구지 Vol.7 No.-

In Conclusion, it is demanded that we throw away a fixed idea that commercial sports facilities are inferior and that we think its desirable direction of development and prepare a positive policy for it as a social physical education sports facility. We ought to not control it by using the laws of merrymaking businesses but consider the way to guide, assist, and encourage it at a dimension of Physical education development from seperate point of view as stated above. It Plays roles to replenish the shortage of public sports facilities especially in our country, So we first evaluate its roles to be being carried out and its performance limit properly and need to grasp newly the roles of public, private and commercial physical education and sports facilities in the whole organization of social physical education. While the national interests and demands in sports are being expended and accelerated nowadays, if commerical sports facilites are negleated in the contempt and indifference in the actual situation of these days, witout the reasonable conversion of conciousness of the people in the administration authorities about this or the propulsion of constrution of public facilities, the menbership free of menbers using facilities will inevitably soar, the approach of most general public enjoying sports to these facilities will be more difficults, and the alienated people from sports facilites may diffuse the conflict and stress caused by a remarkable contrast of the wealth of money by doing various kinds of antisocial and unadaptable behavior and by drinking too much enough to injure health. These make sports for participating and acting disappear and make sport for just hearing and Watching. This was happended severely in the past and it turns away the essence of soprts while the former is a conflict among castes caused by the superiority and inferiority of sports technics, but a phenomenon of these days is a conflict among castes caused by the distinction of the wealth of maney. This promotes the feelings of distance among people and misleads the vigor of living sports, the sports of our life.

브랜드 이미지, 브랜드 신뢰 및 브랜드 애호도의 구조적 관계 : 금융브랜드 이미지를 중심으로

안길상,이재록,민경현 한국방송광고공사 2005 광고연구 Vol.0 No.69

본 논문은 브랜드 이미지와 브랜드 신뢰 그리고 브랜드 애호도에 관한 구조적 관계를 실증분석을 통해 검증하고자 하였다. 이를 위해 은행을 이용해 본 경험이 있는 고객들을 상대로 설문조사를 하였으며 수집된 자료를 이용하여 구조방정식에 의해 브랜드 이미지, 브랜드 신뢰, 그리고 브랜드 애호도 간의 인과관계를 검증하였다. 분석결과 브랜드 이미지는 브랜드 신뢰에 브랜드 신뢰는 브랜드 애호도에 직접적으로 영향을 미치는 것으로 나타났다. 또한 브랜드 이미지와 브랜드 애호도와의 관계에서 브랜드 신뢰는 부분적으로 매개적 작용을 하는 것으로 나타났다. 마지막으로 연구결과에 따른 실무적 시사점과 연구의 한계점 및 미래 연구방향에 대해 기술하였다. This study examines the structural relationship among brand image, brand trust, and brand loyalty in bank industry, and then how brand trust plays a role of mediating variables between brand image and brand loyalty. Findings of this study are as follows: First, the brand image is significantly related to brand trust. The more consumer arouses about brand image, the more he trust the brand.Second, brand trust affects brand loyalty. Creating and maintaining brand trust produces positive results in repeat purchase and word-of-mouth activities. Third, brand trust is definitely found as a mediating variables which illustrates the relationship of brand image and brand loyalty. This paper suggests some marketing implications. First, it is possible to place a powerful brand when a brand has strong, favorable, and unique brand image. Bank industry should endeavor to build and maintain a strong, favorable, unique brand image because the powerful brand leads to brand equity. Second, financial goods in bank do not still perform in their strong, favorable and unique brand image attributes. Therefore banks provide consumers the strong, favorable, unique brand image in financial goods through effective communications.

곡관덕트에서 난류정상유동의 벽면전단응력분포와 입구길이에 관한 실험적 연구

손현철,이홍구,김대욱,김명호,박길문 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.1

In this paper, an experimental investigation of characteristics of developing turbulent steady flows in a square-sectional 180°curved duct is presented. The experimental study using air in the square-sectional 180°curved duct is carried out to measure entrance length and wall shear stress distributions by using Laser Dopper Velocimeter(LDV) system with data acquisition and processing the system of FIND6260 software at 7 sections from the inlet(ø=0°) to the outlet(ø=180°)in 30°intervals of the curved duct. The results obtained from experimental studies are summarized as follows : (1) The critical Dean number of turbulent steady flow is about 560. (2) The value of the wall shear stress becomes minimum in the inner wall and gradually increases toward the outer wall where it becomes maximum. (3) The entrance length of the turbulent steady flow is shorter than that of the traditional steady flow, reaching the vicinity of bend angle 90°

곡관 덕트내 난류 비정상유동의 압력분포

박길문,이행남,백대우,손현철 朝鮮大學校 機械技術硏究所 2000 機械技術硏究 Vol.3 No.1

In this study, Flow characteristics of turbulent unsteady flows in a square-sectional 180°curved duct were experimentally investigated. Experimental studies for air flow were conducted to measure pressure distributions in the square-sectional 180°curved duct by using a magnehelic differential pressure gage. The experiment were conducted in nineteen sections from the inlet (ø=0°) to the outlet(ø=180°) of the duct at 10°intervals. The results obtained from the experimentation are summarized as follows. (1) In the turbulent oscillatory flow, the pressure distribution was the largest in the accelerating and decelerating region of the bend angle of 90°and the pressure difference of the inner and outer walls was the largest before and after the bend angle of 90°. (2) In the turbulent pulsating flow, the pressure difference was the largest near the region of bend angle of 90°in the case of the middle region, and since then the pressure difference of the inner and outer walls became smaller.

1-MCP처리가 '신고'배의 저장에 미치는 영향

한현희,강충길,이정명 경희대학교식량자원개발연구소 2005 硏究論文集 Vol.24 No.-

1-MCP 처리가 '신고' 배품종의 상온저장시의 품질에 미치는 영향을 알아보고자 실험을 실시하였다. 수확된 '신고' 배를 1-MCP 1 ppm의 농도로 수확당일, 수확후 1일, 수확후 2일에 각각 처리하고 이후에는 20±2℃의 실온에서 포장 저장하면서 품질관현 요인을 검정하였다. 초기 조사일의 과중에 대한 중간 조사일의 과중감소율에서는 5주차에 수확 1일후 1-MCP 처리구가 가장 감소율이 적었다. 당도에서는 처리간에 차이가 없었다. 경도와 부패과에서는 처리 5주차에서 1-MCP 처리구들이 무처리에 비해 뚜렷하게 경도와 부패과가 적게 발생하였다. 산도에서는 실험 5주차에 무처리가 다른 1-MCP 처리구보다 높았다. 결론적으로 수확직후의 1-MCP처리는 '신고' 배의 저장기간 연장에 효과적이었다. This study was carried out to find out the effects of 1-MCP treatment on the fruit quality of 'Niitaka' pear under room temperature storage conditions. With 1-MCP treatment one day after harvest, the lowest percentage of decrease in the fruit fresh weight was obtained at 5 weeks after the treatment. Soluble solids contents of MCP-treated fruit did not show significant differences among treatments. In comparison with the control, all of 1-MCP treatments showed a slow decrease in fruit firmness and low percentages in rotten fruit rate at 5 weeks after the treatment. At 5 weeks after the treatment, the fruit juice acidity of the control was higher than those from other 1-MCP treatments.