월류제를 이용한 항내의 해수교환에 관한 연구

이규성 群山大學校 産業大學院 2003 국내석사

한국산 갈돔과(농어목) 어류의 분류학적 연구

김은영 群山大學校 産業大學院 2004 국내석사

2000년 7월부터 2003년 12월까지 우리나라 연안에서 채집된 갈돔과 어류의 주요 계수계측 형질과 형태적 특징을 분석하여 분류학적으로 검토하였다. 연구 결과 한국산 갈돔과 어류는 까치돔 Gymnocranius griseus, 줄갈돔 Lethrinus genivittatus, 구갈돔 L. haematopterus, 점갈돔 L. harak, 갈돔 L. nebulosus등 모두 2속 5종으로 조사되었다. 이 가운데 점갈돔 L. harak은 한국미기록종으로 확인되어 계수계측치 및 형태적 특징을 기재하고, 국명을 「점갈돔」으로 명명하였다. 점갈돔은 뺨에 비늘이 없고, 가슴지느러미 안쪽 기부에 작은 비늘이 있으며 체측 중앙에 흑갈색의 큰 반점이 있는 점이 특징이다. 본 연구에서는 한국산 갈돔과 어류 2속 5종에 대한 형태적 특징과 함께 검색표를 제시하였다. The taxonomic study of the family Lethrinidae was made based on the specimens collected from the off Korean sea waters from July 2000 to December 2003. The family Lethrinidae from Korea was classified into 5 species: Gymnocranius griseus, L. genivittatus, L. haematopterus, L. harak, L. nebulosus. Of them L. harak was reported for the first time in Korea. L. harak was characterized by having no scaless on cheek, many minute scales on inner base of pectoral fin and large black blotch on body sides. The their morphological measurements and counts were described in detail and a key to species of the family Lethrinidae from Korea proposed in this study.

유·무연 혼합탄의 수소첨가 가스화반응 특성 연구

이영규 群山大學校 産業大學院 2003 국내석사

Some of advanced countries have studied the development of substitute natural gas for long periods in consideration of the coal utilization and the limitation of natural gas resources. For the effective conversion of coal by hydrogasification, batch reactor of 110ml was designed. Novo coal from Austrailia and domestic coal were selected for the experiments. The product gas composition was determined by quantitatively analysing for H_(2), CH_(4), CO, CO_(2) and H_(2)O. If was found that rate of pressure decrease was closely related to the rate of gas production. This result was confirmed by the change of carbon conversion with time. The rate of carbon conversion and gas production was measured over a various range of temperature and pressure. The gas composition and carbon conversion depend on the temperature and pressure. The methane content of gas products and carbon conversion rise with temperature and pressure. The addition of water activates hydrogasification reaction until the proper level, but in the excess level inhibits. In case of loading of catalyst, all catalysts loaded to the coal did not give a positive effect in hydrogasification, but depends on type of metals and coal. In the hydrogasification of mixture of bitumious and anthracite coal, K_(2)CO_(3) catalyst was the best.

이동 에이전트의 信賴性 向上을 위한 保安體系 硏究

최용준 群山大學校 産業大學院 2003 국내석사

이동 에이전트는 서버의 인터페이스를 변경하지 않으면서도 클라이언트의 다양한 요청을 융통성 있게 서비스 할 수 있는 기술이다. 이러한 이동 에이전트는 이동성을 갖춘 프로그램이므로 우연성과 용이성을 제공해 주지만 심각한 보안 문제를 안고 있다. 보안문제에는 불완전한 통신채널을 이용할 때 발생되는 문제, 이동 에이전트가 행하는 불법적인 공격에 대한 호스트 컴퓨터나 서버의 보호문제, 그리고 에이전트 서버가 행하는 에이전트에 대한 보안 문제이다. 본 논문에서는 이동 에이전트 시스템의 보안문제 중 에이전트가 에이전트 서버로 이동시 서버로부터 받을 수 있는 공격에 대응할 수 있도록 디지털 서명방식과 이동 에이전트 보안서버(MASS : Mobile Agent Security Server)를 이용한 보안체계를 제안한다. Mobile agent technology offers flexible services for the various requests of clients without changing the interface of the servers. Though it is a program that has the mobility and offers the easiness with the softness, these advantage raise essential questions closely related to security issues. These security issues are the problems when the agent using imperfect communication channels, protecting host computers and servers against malicious agents and protecting agents from malicious hosts. This paper suggests security system based on MASS(Mobile Agent Security Server) and digital multi-signature scheme which enable mobile agents to cope with one of the security breaches of mobile agent systems, which is the attack of servers when agents move the agent servers.

음향신호의 주파수 분석을 이용한 선박기관의 고장진단에 관한 연구

남종수 群山大學校 産業大學院 2003 국내석사

This paper intends to diagnose fault by analyzing frequency of sound signal occurring in engine, using ordinary software sound that one of low-price trouble diagnosis system adopted in real time monitoring system for automatic vessel. This experiment regards as defect condition by control at its option suction·exhaust tappet clearance as a method to simulate fault and then compares after collecting engine sound while normal and abnormal. Engine sound signal is analysed by FFT frequency spectrum. The results show that engine sound had the most energy source in the frequency around 2000Hz in common each stroke. And according to RPM increasing, above the 4000Hz sound is shown higher than around the 2000Hz sound. In case of normal and abnormal condition, engine sound makes a clear distinction in the frequency area of above the 4000Hz.

주정폐수의 생물학적 질소제거시설 설계에 관한 연구

노남윤 群山大學校 産業大學院 2003 국내석사

This study is designed for treating total nitrogen included in the wastewater of alcohol distillation factory below exhaust permission standard by the way of biological process. This experiment is conducted by indoor continuous reactor and the raw wastewater in this experiment is the alcohol distillation wastewater removed solids by D.A.F through anaerobic digestion process. In the operation of nitrification tank, it is proper that loading rate per volume of ammonia nitrogen is less than 0.45Kg NH_(3)/㎥ and the rate of nitrification is over 95%. It is suitable that loading rate per volume of rear denitrification tank is 1.0 - 1.8Kg Nox/㎥. More than 90% of denitrification is showed and the efficiency is increased drastically since T-N internal recycled. Based on the result, if the facilities such as front denitrification tank, rear denitrification tank etc. is added to the existing biological alcohol wastewater treatment process, the removal of nitrogen in the alcohol distillation wastewater is expected to be more than 95%.

엔드밀 가공시 절삭방향에 따른 절삭특성에 관한 연구

임채문 群山大學校 産業大學院 2003 국내석사

엔드밀은 3차원 곡면가공에 가장 널리 사용되는 공구중 하나이다. 특히 곡면을 갖는 다이와 몰드가공에 주로 사용된다. 최근에는 경쟁력을 갖기 위해서 제품의 생산성과 경제성뿐만 아니라 고품질의 제품 생산이 요구되고 있다. 최근 공작기계의 정밀화, 자동화과정에서 가공물의 고품질을 보증하기 위한 한 가지 방법으로 공구파손 또는 과대한 공구의 변형을 피하기 위해 금속제거율 측면을 고려하여 절삭조건을 선정해 왔다. 본 논문에서 경사면을 가공할 때 공구경로에 따른 절삭특성에 관점을 두어 연구 하였다. 동일한 경사면에 대해 각각 상향절삭과 하향절삭이면서 4가지 공구 경로로 가공했을 때 실험적 결과를 나타낸다. 공구수명을 향상시킬 수 있는 최적절삭조건을 얻기 위해 절삭력, 칩의 형상 그리고 공구마모와 같은 절삭특성을 분석하고 비교하였다. The end mill is one of the most widely used cutting tools in the machining of parts with 3-D sculptured surfaces. Especially this is generally used in machining dies and molds with sculptured surface. The needs to machine hardened steels with high productivity and good surface integrity have been increasing in the dies and molds industry. One way to assure high quality of the machined product is to be conservative in selecting machining conditions with respect to metal removal rate so as to avoid excessive cutter deflection or cutter breakage. In this paper, the investigation concerns on the effects of cutting path when the inclined surface are cut. This presents some experimental results on the end milling with four tool paths on the same inclined surface. With the same inclined plane, cutting was carried out in four cutting paths in up-milling and down-milling. Cutting characteristics that are cutting force, chip shape and tool wear were analyzed and compared and this paper gives the optimum cutting path such that tool life can be improved in end milling.

군산-장항 실트질 점토의 침강 및 자중압밀 특성 비교

김두환 群山大學校 産業大學院 2006 국내석사

When dredging it is an important factor to investigate the settlement feature of reclamation soil itself and the amount of consolidation and consuming time in making dredged reclamation ground after reclamation. Also, reclamation soil in the region of Gunsan and Janghang accumulates entirely different the topsoil of dredging zone and the composition of a sedimentary layer in the reclaimed land by the fine grained soil on divided sedimentation so it is necessary to predicted the amount of the fine grained soil as in a state of sedimentation. Thus so as to solve this kind of problem and indicate the soil parameters precisely using dredged reclamation in sample of the region of Gunsan and Janghang and in a state of slurry operating a series of self-weight consolidation or seepage consolidation, thus presenting sedimentation and self-weight consolidation characteristics and designed soil parameters of the dredged soil when designing it is possible to predict the settlement of the very soft reclamation ground in sedimentation self-weight consolidation. As a result, the larger the fine grained soil content, the faster the settling velocity of the reclamation soil in the Gunsan and Janghang region. Therefore as the rate of somewhat bigger grain size we judge that the dredged soil is highly affected by the divided sedimentation. Besides, there is no big difference in the consuming time of sedimentation self-weight consolidation as the amount of fine grained soil content. But as the amount of settlement increases, the consuming time of sedimentation self-weight consolidation increases.

수협 영업점 관리 시스템 구현에 대한 연구

김재원 群山大學校 産業大學院 2003 국내석사

컴퓨터의 빠른 보급과 인터넷이라는 신기술의 발전으로 인하여 전 세계의 모든 산업 형태가 디지털 경제라는 새로운 패러다임을 중심으로 변화를 꾀하고 있는데, 이러한 디지털 경제 시대에서 기업활동의 효율성을 높이고 생산성을 향상시키며, 경쟁력을 높이는데 결정적인 역할을 하는 것 중 하나가 바로 인트라넷 기술이다. 인트라넷은 인터넷의 웹(Web)기술을 이용하여 특정 단체의 내부(Intra) 관련자들이 필요한 정보를 공유하게 하는 네트워크 시스템을 의미한다. 본 연구에서는 인트라넷을 활용하여 산재해 있는 수협내의 각 영업점 관리 방식을 통해 비용을 절감하고 각 영업점간의 정보공유 및 통합적인 관리의 효율성을 입증하고자 한다. 그리고 장소와 관계없이 실시간으로 요약된 정보를 조회할 수 있기 때문에 신속하면서도 효율적인 의사결정을 지원할 수 있으며 고객에 대한 만족할 만한 서비스를 제공하는데 있다. 이를 위해 현재 수협의 인터넷 활용 현황과 기존의 영업점관리 방식을 알아보고, 기존의 업무 방식과 인트라넷을 통한 영업점관리방식을 도입한 후의 업무관리와 고객 관리를 비교 분석함으로써 본 연구에서 제시하고자하는 인트라넷을 활용한 영업점관리모형의 효율성을 입증하기로 한다. 본 연구에서 제시된 인트라넷 모형은 비용이나 호환성, 데이터 공유 등의 많은 이점도 가지고 있지만, 보안에 취약하며 제반기술부분에서 문제점을 가지고 있다. 그러나 인터넷 기술이 점차 발전되고 있으므로 해결될 것으로 보인다. 기술의 발전 정도에 따라 인터넷을 도입하는 방법도 점차 다양해지고 여러 가지 기법이 추가되고 수용될 수 있을 것이다. With the widespread of computers and advancement of new technology called "internet", all kinds of industries in the world are changing based on the new paradigm focusing digital economy. In this digital economic age, it is the technology, "internet" that plays an important role in improving the efficiency and productivity of industrial performance, in order for businesses to strengthen their competitiveness. Internet is a kind of network system designed for intra workers in some specific organizations to share required information by using web on the internet. This is to find out a way to reduce costs by supervising all separated the National Federation of Fisheries Co-operatives branch offices and to prove the effectiveness of data-common use by all the branch offices and integrated management of them. Besides, intranet-work system is able to provide the customers with satisfactory service in that they can retrieve real-time summarized data regardless of time and places for their fast and effective decision-making, Accordingly, this study is aimed first to investigate, the National. Federation of Fisheries Co-operatives present state of internet use and management way of all branches second, secondly, to compare the current management system with the work and customer management system after the introduction of internet for branch offices, and finally to prove the efficiency of internet-based branch management model targeted in this study. This presented internet model has a lot of advantages, such as cut-costs, interchangeability, data-sharing, it, however, can be loose In security and has some problems in its infrastructure. But we can hope those problems can be solved, because of the dramatic advancement of internet technology. The ways to induce internet have been, and also will be diversified in the future and as a result, various new system will be added to them.

건식 가스 스월버너의 슬릿부와 스월베인부가 주 유동장에 미치는 영향

부성보 群山大學校 産業大學院 2003 국내석사

This paper is studied to investigate the effects of slits and swirl vanes on the main flow fields of gun-type gas swirl burner. Also, this study analysed the vector fields and three dimensional mean velocities, the turbulent intensities, the turbulent kinetic energy etc. These were obtained by using an X-type hot-wire probe from the hot-wire anemometer system in the X-Y plane and in the Y-Z plane of gun-type gas swirl burner. This experiment was carried out at flowrate 450 ℓ/min, which is equivalent to the actual combustion air flowrate necessary for heat release 15,000 kcal/hr in gas furnace, in the test section of subsonic wind tunnel. The results obtained through the comparison among three kinds of burner models are as follows; 1) The axial mean velocity component shows that the fast jets by slits surround the rotational flow by swirl vanes which spread radially. The inertia of the rotational flow largely works in the central region of a burner by air-curtain effect due to the fast jets and the rotational flow goes partly through the narrow border region between slit and slit. 2) Therefore the more spreaded flow width due to strong velocity can be shown within about Y/R = ±1.5 radially in the initial region of about X/R = 1.5. Especially, because the fast jets play the role that the rotational flow cannot turn toward radial direction any more in the central region of a burner, and they drive the main flow including rotational flow to axial direction, the rotational flow by swirl vanes works much stronger relatively in the central region of a burner. Also, the axial mean velocity component is largely distributed in the central part of a burner. 3) The axial component of turbulent intensity and the turbulent kinetic energy in gun-type gas burner have the large values within about X/R = 1.5 stressing on the outer edge of swirl vanes and the near slits because inertia of the rotational flow strongly induces in these places as a result of that the fast jet of slits surrounds the rotational flow. As the axial distance increases, they have the large and even magnitude relatively in the central part of a burner because the fast jet flow formed near the silts decreases greatly and it drives the rotational flow to the center. 4) Slits cause the fast jets, and then they have the characteristics that the flow is not adequately spread to radial direction and has long flow length as well as very small flow velocity in the central part. On the contrary, swirl vanes does not have long enough for adequate flow length to downstream because the rotational flow diffuses remarkably to radial direction. 5) The suitable arrangement between slits and swirl vanes causes effective flow width and flow length, and then it promotes fast flow mixing over the entire region including central part to increase turbulence more largely and effectively. Therefore, it is thought as a very desirable design method in gun-type gas burner to locate slits on the outside of swirl vanes.