In order to investigate characteristics of SBP (Subbottom Profiler) seismic data energy envelopes are obtained by using a CWT (Continuous Wavelet Transform) of raw data and Hilbert transform. In addition, energy envelopes which are obtained using a conventional band-pass filtering and low-pass filtering method are compared with those obtained by a CWT method. Energy envelope obtained by using a CWT method is pretty much similar to cubic spline curve which is constructed by connecting positive peaks of the raw data. Energy envelopes obtained by CWT method reflect energy distribution contained in the signals better than those obtained by conventional filtering method do.

  This study is to perform the numerical simulation to predict the development of the ship waves and their propagation in shallow water region for Busan New Port. In order to predict the propagation of ship waves according to various ship"s size and weight tonnage under shallow water depth, a computer model is developed based on Boussinesque equation with a fixed coordinate system. Also, the simulation is performed using program developed by Namseeg Hong in order to make the propagation form of the ship waves. The simulation shows the propagation form of the ship waves and the wave height in front of the sea wall. It is found from the investigation of simulation results that the effect of ship wave is negligible at the Busan new port.

  The study to predict changes of the ocean environment should be proceeded in advance to design and construct coastal structures. Especially, the diffusion in the nearshore zone due to coastal development is a one of main issues in the coastal engineering.
  The simulation for the diffusion was performed, which is based on the numerical simulation by using Delft-3D in this study. The study area was chosen as Ulsan New Port and the simulated data were compared with the field data.
  The qualitative results were fairly good agreement with field data. The quantitive results show a little differences with field data and the improvement of input data and parameters calibrations will give better results in the future.

  To detect defects under the surface of a acryl plate, the infrared thermography was applied. The defects of specimen were made by back-drilled circular holes. To get the large difference of temperature of the surface, a halogen lamp was used. The location of defect is a good agreement with the maximum temperature contrast. The sizes of defects are calculated by means of FWHM. In case of large defect, the sizes of defects were estimated exactly comparing to real size. FWHM was decreased with time. In case of small defect, FWHM was increased with time. The temperature contrast was initially increased and finally decreased with time in both case.

  This study developed several ecological maps with GIS database based on the analysis of existing ecological survey reports and the change detection on the Nakdong river estuary by using Remote Sensing and GIS. The data which are used to analyze the spatiotemporal change detection are from the spatial resolution of 30m Landsat TM images Nov, 31, 1984 and May, 17, 1997 and 1/25,000 topographical maps established by National Geography Institution, various data published in Pusan metropolitan government. The developed ecological maps with GIS database can be used for an effective mechanism for managing the ecosystem.

  CTD and ADCP data obtained in summer from 2004 to 2006 was analyzed for the study on the mixing of Nakdong Estuarine water with sea water. Water mass in this research area can be classified into Nakdong Estuarine water, Tsushima warm current, bottom water and mixture of estuarine water and sea water.
  It was found that mixing characteristics of Nakdong Estuarine water and offshore water changes because of the change of ambient current field, which is caused by wind speed, period of spring and neap tide, and amount of discharge of Nakdong Estuarine water.

  This study is intended to describe and suggest the future applications in the field of Marine Technology(MT), which are is provided by National Differential Global Positioning System(NDGPS) infrastructure in Korea. Such countries as Japan, Australia, Europe, and the United States have reviewed various applications by using DGPS positioning technology with high accuracy of submeter level. Many researchers have found several applications usable by NDGPS. Korea government is also seeking for applications to efficiently utilize NDGPS services. In this paper, we defined the characteristics of Global Navigation Satellite Services(GNSS) position services with high accuracy in the field of Marine Technology(MT). The suggested services would help expand the future applications for NDGPS in Maritime areas.

  The fabricability, good corrosion resistance and high thermal conductivity of aluminum brass (Al-brass) material has made it widely used in heating coil units of crude oil carrier vessels. But because of bad brazing technique, unexpected leakage some times occurred. To know the exact bonding state, the ultrasonic and X-ray test of tube which was brazed were done. The ultrasonic test is not a good method to know brazing state of tube. By the X-ray test, it is recognized that to know the exact brazing state of Al-brass tube is possible. And a new heating method of brazing should be developed to get a good bonding state.

  A study on the comparison of magnetic gradient obtained by the forward modeling and the field test for a finite line of dipoles was carried out. From the field test horizontal gradient of horizontal component, that of vertical component, and that of total magnetic field were measured by using an 1-m long anchor layed on the ground, For the numerical modeling it was assumed that an 1-m long line of dipoles with declination of 45°, inclination of -5° are buried in the depth of 0.1 m pointing the North. From this study we can conclude that the anchor can be used as a model of finite line of dipoles, and the horizontal gradients in the direction of declination of the dipoles were maximized. In addition, it is recommended that the survey direction coincide with the declination of the anomalous object of a line type.

  In order to measure the extent of corrosion of rebar in the concrete, two types of arrangement of the wenner probe to rebar was used. The concrete was corroded in the 3 % NaCl solution. In case of shallow depth compare to cover depth, the electrical resistivity of parallel arrangement of wenner probe is higher than that of normal arrangement. This is thought to be related with the size of specimen. The electrical resistivity is same about 0.6 ㎝ ahead of rebar when two types of arrangement of the wenner probe to rebar is used. With the extent of corrosion the electrical resistivity was decreased.

  한국의 연안에는 심각한 이해상충이 발생되고 있다. 그러나, 연안관리를 일찍 도입한 국가에서 도입되고 있는 이해상충 조정 프로그램이나 조정자의 역할이 부재하다. 본 연구의 목표는 우리나라 연안에서 발생되고 있는 이해상충을 평가하기 위해 평가기준의 정립과 그 특성을 구분하는데 있다. 국내외 연안관련 갈등사례를 정리한 이후, 사례조사로 시화호를 둘러싸고 전개되었던 이해상충을 소개하고 관련자의 3차에 관한 설문조사를 근거로 이해상충 평가에 중요한 인자를 정리하였다.

  Wave monitoring around in the Ulsan New Port area is proceeding by Hyundai construction company form Nov. 2005 by using USW300 which is supplied by KAIJO (Japan Manufacturer). The observed data was analyzed in this study and the observation period is from Nov. 2005 to Oct. 2006. The analyzed significant wave heights, max. wave height, significant wave period and max. wave period are included in this study. The seasonal data analysis is also proceeded and the results are shown. The observation period is less than one year and some period (May. 2006, Apr. 2006 and Jul. 2006) was missing and thus the analysis is not sufficient for having a good results. The wave monitoring in the Ulsan New Port area is subjected to go the end of Jan. 2008. And thus the results of this study will be covered afterward.

  Wave overtopping has been studied under the view of its reducing capability of the various wave dissipating structures.
  Therefore, researches for the effect of harbour tranquility caused wave overtopping are insufficient. In this study, it was analyzed the effect of harbor tranquility by wave overtopping of breakwater concerning design wave through a three dimensional hydraulic model test. The averaged significant wave height is distributed as 2.16m in permitted wave overtopping, 1.63m in not permitted. The decreased wave height is shown as 50㎝ and 24% of desigh wave height in not permitted wave overtopping.

  지형 및 지질 특성으로 인하여 지표수 또는 지하수 등의 수자원 확보가 어려운 도서 및 해안지역과 상수도의 혜택을 받을 수 없는 지역 등에서는 수자원 개발이 불가피한 실정이다. 정부차원에서 추진하고 있는 대체수자원으로서 해수의 담수화사업은 고에너지가 소요되고 용수 개발에 따른 국민부담을 가중시키게 될 것이므로 사업을 실시하기 전 사업의 타당성을 검토하는 것이 필수적이다.
  본 연구는 사면이 바다로 둘러싸인 협소한 섬지역에서의 농업용수 확보 및 주민의 생활용수 공급을 위한 목적으로 제주도 추자도를 대상으로 지질분포조사와 지하수 개발가능성 평가를 위해 국내에서 가장 빈번하게 적용하고 있는 2차원 전기비저항탐사와 수직탐사를 실시하였고, 지표지질조사 결과를 토대로 6개의 쌍극자 배열 전기 비저항탐사를 실시하여 2차원적 지질구조를 해석한 후에 지질구조대 및 파쇄대 발달이 예상되는 4개 지점을 설정하고, 슐럼버져 배열법에 의한 수직탐사를 실시하고, 해석결과 3개 공에 대해 파쇄대 구간을 탐지, 시추조사를 위한 기초자료로 이용하였다. 시추조사 결과 2개 공은 담수의 양수량이 풍부한 암반관정으로 확인되었으며, 1개 공은 양수시험 중 해수의 유입이 확인되어, 양수시험을 중단하였고, 후에 담수화 사업시 활용 가능할 것으로 사료된다.

  When four boreholes are installed in the cast-in-place pile, coordinates of the boreholes are obtained by using a least squares method, utilizing six hole-to-hole distance measurements. In addition, most probable values of hole-to-hole distances are calculated with coordinates of the boreholes. With the knowledge of borehole coordinates sound velocity of the pile can be obtained more accurately, and the cross section of the pile can be drawn with the drawing program easily. Also, coordinates of the boreholes would be very useful when a horizontal tomography technique is applied for integrity test of the cast-in-place pile.

  This study has examined the stability of T.T.P, wave height distribution of sea area in front of lock gates and revetment on Jang hang zone of Kun-Jang industrial complex(KJIC) by three dimensional hydraulic model test.
  KJIC is situated in Korean western sea, which the tidal difference is very high by 8.54 m. The design wave height has been calculated very greatly by 4.4m in spite of water depths, D.L (-) 4 m ~ D.L (-) 11m.
  As for the experimental result, the observation point is 100m far from lock gate and revetment to sea direction that show wave height distribution 4.5 m, and 100m ~ 400m high wave height distribution of 5.3 ~ 6 m.
  The Stability of T.T.P (10ton) appeared to be stable for the design wave. 1% breakaway of T.T.P(10ton) occurred in an experiment, and is thought to be there is no big problem in stability even if the design weight of T.T.P (10ton) is little bit small because the stability is permissible range 5%.

  A sparker source with the center frequency of 1㎑ or higher can not be easily applied for the multi-channel marine seismic survey because of stacking difficulties. Thus, it has been applied mainly to the single channel marine seismic survey. For examining the applicability of sparker source to multi-channel marine seismic survey, 8-channel seismic data were obtained from the field and processed, and a 2-D seismic section was drawn up. From this study it can be concluded that, a sparker source with the center frequency of 1㎑ or higher can be applied to the multi-channel marine seismic survey, and the seismic section with high vertical resolution can be generated. The high-resolution seismic section would be very useful for subsurface geological structure analysis in the shallow sea.