• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.85-92
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• 2008

National Oceanographic Research Institute is carrying out an oceanographic survey for the entire sea areas around Korean Peninsula annually starting with the East Sea from 1996 by establishing a national oceanographic basic map survey plan for the sea areas under the jurisdiction of Korea, so this paper used the oceanographic geomagnetism data measured at the southern area of the Yellow Sea using 'Hae Yang 2000' in 1999, aiming at clarifying the cause of geomagnetic abnormality zone during the course of treating and analyzing the geomagnetic data. For treatment of magnetic data, we obtained electromagnetic force values and geomagnetic abnormality values around the investigated sea area through a process of searching and removal of bad data, correction of sensor positions, correction of magnetic field effects around the hull, correction of diurnal variation, normal correction, correction of cross point errors, etc. The electromagnetic force distribution around the investigated sea area was $49000\;{\sim}\;51600\;nT$, which is judged to be within the normal electromagnetic force intensity distribution range around the Yellow Sea. The isodynamic lines are distributed in Northeast-Southwest direction, and electromagnetic force values are increasing toward the northwest. The result of comparing the magnetic abnormality around the sea area among $124^{\circ}$ 49' 48" E, $35^{\circ}$ 10' 48" N $\sim$ $125^{\circ}$ 7' 48" E, and $35^{\circ}$ 33' 00" N sections with the elastic wave cross section and the result of modeling coincide well with the underground geological structure clarified from the existing elastic wave survey cross section. Therefore, it is judged that the distribution of magnetic force abnormality generally shows the effect pursuant to the distribution of the sedimentary basins in the Tertiary period and the bedrocks in the Cretaceous period which are well developed in the bottom of the sea.

• Bulletin of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.39-46
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• 2017

Jack-up drilling rigs are widely used in offshore oil and gas exploration industry. It is originally designed for use in the shallow waters less than 60m of water depth; there is growing demand for their use in deeper water depth over 150m and harsher environmental conditions. In this study, global in-place analysis of jack-up rig leg for North-sea oil well is performed through numerical analysis. Firstly, environmental conditions and seabed characteristics at the North-sea are collected and investigated measurements from survey report. Based on these data, design specifications are established and the overall basic design is performed. Dynamic characteristics of the jack-up rig for North-sea are considered in the global in-place analysis both leg and hull and the basic stability against overturning moment is also analyzed. The structural integrity of the jack-up rig leg/hull is verified through the code checks and the adequate safety margin is observed. The uncertainty in jack-up behaviour is greatly influenced by the uncertainties in the soil characteristics that determine the resistance of the foundation to the forces imposed by the jack-up structure. Among the risks above mentioned, the punch-through during pre-loading is the most frequently encountered foundation problem for jack-up rigs. The objective of this paper is to clarify the detailed structure and installation engineering matters for prove the structural safety of jack-up rigs during operation. With this intention the following items are addressed; - Characteristics of structural behavior considering soil effect against environmental loads - Modes of failure and related pre-loading procedure and parameters - Typical results of structural engineering and verification by actual measurement.

• Journal of the Institute of Convergence Signal Processing
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• v.21 no.1
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• pp.13-20
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• 2020

In shipyards, internal materials are assembled after designing and manufacturing each ship's block. Internal material assembly means the installation of parts and equipment except ship's body. In this process, if the assembly of pipes and equipment existing in the block is not done correctly during the assembly between blocks, this causes a lot of costs. In addition, even if the assembly of the internal materials already completed, the production efficiency of the ship is reduced due to rework when problems such as space arrangement of the internal materials occurs. Therefore, this study introduces space arrangement and inspection system before and after hull outfitting work based on coexistence reality technology using 3D design drawing to solve these problems. The various coexistence reality algorithms and inspection systems developed and introduced in this study are based on AR service, which has never been introduced in Korea. So it will be widely applicable to various manufacturing industries using design drawings such as automobiles and architectures as well as ship building process.

• Journal of Veterinary Clinics
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• v.9 no.1
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• pp.273-276
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• 1992

Present study was undertaken in order to evaluate the lead contents of various feedstuffs produced in Chonbuk area. Fifty-five samples were collected from 5 regions. All of the samples were dry-ashed and analyzed for lead content using atomic absorption spectrophotometer. The results obtained were summarized as followed : 1. The lead content in $\mu\textrm{g}$/g of agriculture by-products were measured with the following mean values and ranges : soybean pod 7.01${\pm}$2.49(4.71∼10.66), rice bran 4.56${\pm}$0.90(3.17∼5.65), rice straw 3.89${\pm}$2.01(1.29∼6.33), rice hull 1.92${\pm}$1.77(0∼3.63). 2. The lead content in $\mu\textrm{g}$/g of pasture plants were measured with the following mean values and ranges : kudzu 20.29${\pm}$4.75(14.84∼25.34), clover 13.92${\pm}$2.68(10.17∼16.44), lespedeza 10.91${\pm}$9.00 (3.35∼23.54), sagebrush 10.75${\pm}$3.28(5.14∼13.18), Korean lawn grass 5.05${\pm}$2.29(2.57∼7.79), cornstalk 3.91${\pm}$2.55(0.50∼7.22), reed 2.92${\pm}$1.88(0.50∼5.73). 3. Seventeen samples (30.9%) out of 55 samples showed lead content of more than 10$\mu\textrm{g}$/g which are said to be the upper limit value for all animals. 4. The regional mean v짓ues for 리1 kinds of samples were Wanju-gun 10.02${\pm}$8.55$\mu\textrm{g}$/g, Mooju-gun 8.16${\pm}$4.91$\mu\textrm{g}$/g, Namwon-gun 7.09${\pm}$4.59$\mu\textrm{g}$/g, Okgu-gun 7.06${\pm}$7.11$\mu\textrm{g}$/g, Jeongup-gun 6.35${\pm}$6.50$\mu\textrm{g}$/g.

• Journal of Veterinary Clinics
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• v.9 no.1
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• pp.267-271
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• 1992

Present study was undertaken in order to evaluate the cadmium contents of various feedstuffs produced in Chonbuk area. Fifty-five samples were collected from 5 regions. All of the samples were dry-ashed and analyzed for cadmium content using atomic absorption spectrophotometer. The results obtained were summarized as followed : 1. The cadmium content in $\mu\textrm{g}$/g of agriculture by-products were measured with the following mean values and ranges : soybean pod 3.15${\pm}$0.51(2.40∼3.81), rice bran 2.87${\pm}$0.23(2.50∼3.09), rice straw 1.66${\pm}$0.85(1.08∼3.14), rice hull 0.86${\pm}$0.45(0.41∼1.35). 2. The cadmium content in $\mu\textrm{g}$/g of pasture plants were measured with the following mean values and ranges : kudzu 5.65${\pm}$1.00(4.87∼7.29), sagebrush 4.86${\pm}$1.24(2.89∼6.24), clove, 4.28${\pm}$0.75(2.99∼4.86), lespedeza 3.99${\pm}$1.21(2.38∼4.94), Korean lawn grass 2.24${\pm}$1.04(1.33∼3.44), reed 1.99${\pm}$0.95(0.88∼2.91), cornstalk 1.61${\pm}$0.99(0.38∼3.12). 3. The regional mean values for all kinds of samples were Okgu-gun 3.19${\pm}$2.09$\mu\textrm{g}$/g, Mooju-gun 3.15${\pm}$1.73$\mu\textrm{g}$/g, Wanju-gun 3.05${\pm}$1.76$\mu\textrm{g}$/g, Namwon-gun 2.85${\pm}$1.70$\mu\textrm{g}$/g, Jeongup-gun 2.85${\pm}$1.25$\mu\textrm{g}$/g.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.167-173
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• 2009

Bathymetry survey around the Baengnyeong-do was made by the Korea Hydrographic and Oceanographic Administration (KHOA), using the Simrad EM3000 Multi-Beam EchoSounder (MBES) mounted at the hull of the R/V Badaro 1. Sound velocity were monitored with frequent sound velocity profiler(SVP) casts during the acoustic measurements. The depth distribution and fluctuation of thermocline varied locally owing to the effect of several current flows such as Kuroshio current and Yellow sea coastal waters. These uncertainties cause the falling-off in accuracy of MBES results. In this paper, the bathymetry results will be presented and their accuracy will be discussed along with comparisons to the time and spatial variations in sound velocity profile.

• Journal of the Korean Institute of Navigation
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• v.18 no.3
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• pp.51-79
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• 1994

Section 55 (1) of the Marine Insurance Act 1906 states that the insurer is liable for any loss proximately caused by a peril insured against but is not liable for any loss not proximately caused by a peril insured against. It is, therefore, essential to determine whether it is to be recoverable under the Marine Insurance Policy attaching the Institute Cargo or Hull Clauses. But a number of important losses are excluded from the policy by subsection 2 of the same section, unless the policy otherwise provides, although these losses are proximate causes of them. The purpose of this study is to investigate the meaning of proximate cause and excluded losses in the Act. The method of this study is a literature survey. In summary, (1) if the loss is considered to have been proximately caused by a certain peril, and the peril is insured against, the claim is recoverable, (2) if there are different causes resulting in separate losses, the claims recoverable will be those due to insured perils, (3) when the effective cause of the loss is established, remote causes can be ignored, (4) when causes of loss are combined, the claim is recovera-ble if the cause which is proximate in efficiency is an insured peril, (5) if there are two causes, equal in efficiency, the loss is recoverable if one of the causes is an insured peril, but always providing the other cause is merely an uninsured peril rather than a specific exclusion, (6) although certain losses are exclu-ded by section 55 (2) of the Act, with the exception of wilful misconduct of the insured, it is permitted for provision to be made in the policy to widen the terms to include such losses.

• Nuclear Engineering and Technology
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• v.48 no.6
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• pp.1303-1314
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• 2016

This work examines the most viable nuclear technology options for future underwater designs that would meet high safety standards as well as good economic potential, for construction in the 2030-2040 timeframe. The top five concepts selected from a survey of 13 nuclear technologies were compared to a small modular pressurized water reactor (PWR) designed with a conventional layout. In order of smallest to largest primary system size where the reactor and all safety systems are contained, the top five designs were: (1) a lead-bismuth fast reactor based on the Russian SVBR-100; (2) a novel organic cooled reactor; (3) an innovative superheated water reactor; (4) a boiling water reactor based on Toshiba's LSBWR; and (5) an integral PWR featuring compact steam generators. A similar study on potential attractive power cycles was also performed. A condensing and recompression supercritical $CO_2$ cycle and a compact steam Rankine cycle were designed. It was found that the hull size required by the reactor, safety systems and power cycle can be significantly reduced (50-80%) with the top five designs compared to the conventional PWR. Based on the qualitative economic consideration, the organic cooled reactor and boiling water reactor designs are expected to be the most cost effective options.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.2
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• pp.175-186
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• 2019

Number of studies on the buckling of thin cylindrical pressure vessels, such as submarine pressure hull and pipe with a large ratio of diameter/thickness, have been carried out in the naval and ocean engineering. However, research about thick cylinder pressure vessel has not been active except for the specific application in nuclear area. There are not many papers for the estimation of buckling and ultimate load capacity of thick cylinders for the deep sea usage. Thus, it is important to understand the theoretical bases of the buckling and collapse process and the derivation process of such loads for the proper design and structural analysis. The objective of this study is to survey the collapse behavior, to analyse and clarify the derivation procedure and to estimate the ultimate collapse load for thick cylinder by analyzing relevant books and papers. It is found that the yielding begins at the internal surface of the thick cylinder and plasticity develops from the internal surface to the external surface to generate collapse. Also the initial imperfection of cylinder develops flattening and consequently accelerates buckling and finally ultimate collapse. By comparing the collapse loads of aluminum thick cylinder by applying equations herein, it is shown that the equations analyzed are appropriate to obtain collapse load for thick cylinder.

• Journal of Practical Agriculture & Fisheries Research
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• v.9 no.1
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• pp.13-25
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• 2007

The present study analyzed the spatial characteristics of S village according to the Feng-Shui theory(風水理論). People's life span is affected by several factors including hereditary constitution, dietary life and life habits but recently there is an opinion that longevity village in Korea are commonly located in areas at a proper altitude. The objective of the present study was to basic investigate the characteristics of S village from the viewpoint of Feng-Shui(風水). As for this study, it will be given help to a longevity village plan. For this purpose, we conducted field survey and map investigation of the natural geographic situation of S village focused on Ryong(龍, contiguous line of terrestrial stratum), Hull(穴, village location), Sa(砂, geographical feature of surrounding mountains), Su(水, water flow) and Hyang(向), which are Feng-Shui(風水) objects to be observed. According to the result of this research, S Village, which has mountains in the rear and a river in the front, was found to be in fine geographic situation equipped with Sashinsa(四神砂). According to the Feng-Shui theory(風水理論), the village was hang-ju-hyoung(行舟形), which means that people and properties flourish together. A shortcoming of the village was the absence of Ahnsan(案山) to block harmful winds blowing to the fore of the village. In addition, another shortcoming of the village in terms of Feng-Shui(風水) was the large variation of temperature because of its location surrounded by high mountains as if the village was situated inside a bowl. The Hyang(向) of village houses were arranged by the geographical feature and not by Feng-Shui(風水).