• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.558-562
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• 1986

The purpose of this study is to find the light intensity which induces maximum gathering rate and to observe the variation of the gathering rate both in daytime and at night by using marbled sole, Limanda yokohamae (Gunther). An experimental tank ($360L{\times}50W{\times}55H\;cm$) was set up in a dark room. An illumination system was attached to the end of one side of the tank to control horizontal light intensity. Six artificial light sources were prepared by combination of two light bulbs (5W, 150W) and seven filters. During the experiment water depth was maintained 50 cm level in the tank. The tank was marked into six longitudinal sections each being 60 cm long to observe the distribution of fish. The fish were acclimatized in dark condition for 50 minutes prior to the main experiment. Upon turning on the light, the number of fish in each section was counted 40 times every 30 seconds, and the gathering rate was obtained from the average number of fish in each section. The light intensity inducing maximum gathering rate was 1.9 lux ($1.2{\sim}2.9\;lux$) in the daytime and 0.7 lux ($0.5{\sim}1.1\;lux$) at night. The variation of the gathering rate of fish in illumination time was small and comparatively fluctuated with stability.

• Korean Journal of Ichthyology
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• v.31 no.4
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• pp.241-248
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• 2019

The freshwater fish fauna for the whole water system of Geogeumdo Island was surveyed at a total 10 sites from March 2018 to February 2019. During the surveyed period, 13 species belonging to 5 families and 4 orders were collected. Cyprinidae (68.84%) and Gobiidae (18.21%) were the dominant family, and the dominant species was Zacco temminckii (53.71%), and the subdominant species was Rhynchocypris oxycephalus (10.78%). Kichulchoia brevifasciata (1.27%) that endangered species were found in this study, but the habitat was confirmed in one site in Sinpyeongcheon compared to previous literature. Three endemic species of Korea were found in this island such as Iksookimia hugowolfeldi (5.07%), Liobagrus somjinensis (2.99%) and K. brevifasciata (1.27%). According to analysis of fish community structure based on average diversity, evenness index, dominance and richness indices in Geogeumdo Island were 1.666, 0.649, 0.645 and 1.713, respectively.

• Journal of the Korean Society of Marine Environment & Safety
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• v.2 no.1
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• pp.57-65
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• 1996

The latest date, No. 1 YouII was grounded and sunk into the sea at MAMHYUNGJEDO ( South brother Island) in Sep. 21. 1995, and M.V. Sea Prince of V.L.C.C also made a big oil poullution accident owing to Typhoon "Paei" at front sea of Yeu Choun on Jul. 25. 1995. The large or small scall scale of oil poullution accident frequently was occurred about 300-350 cases per ine(1) year. The countries advanced in marine relations like as, nited Kingdom and Japan, have perfect system The country of expert education, training and oil recovery equipments in oil poullution accidents. The large quantity oil skimming ship's basic condition need general skimming ship which was high speed and large quantity skimming ability , and hve to store the recovered oil into tanks This oil skimming shop are composit the skimmer whuch move up and down according to the wace movements, storage tank which storage the recovered oil in after side, transfer pump which transformed from flooding tank to separating tank and separating tank which separated the oil mixtures, Also there are cylindrical floated which keep the auto positing, gate which keep the auto positing, gate which protect and guide the recovering oil from sea and balance weight for skimmer balance. Also there are cylindrical floated which keep the auto positing, gate which protect and guide the recovering oil from sea and balance weight for skimmer balance. The important arrangement is twin arm which moved by two hinge and move te skimming unit by wave movement. In gate of inside, made long wear in the gate bellow position, there are also connected the flexible hose for oil mixtures drop. The separating tank composited with multi-divided bulkhead for ffective oil and sea water separating by settling and flotation principle. As use the above natural princile and equipment, we can remove the large quantity oil by developed oil skimming ship.ming ship.

• Journal of Families and Better Life
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• v.28 no.6
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• pp.81-94
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• 2010

This qualitative research was designed to explore the use of housing among Korean Chinese people in Harbin, China. Focusing on the use which based on the epistemology of housing adjustment, this was particularly designed to examine its cultural assimilation and acculturation on the way of life course, it employed the in-depth interview on the oral history of 5 interviewees in their 60s and 70s, individualized interviews were conducted from May 28 to 31 in 2010. Key findings were summarized as follows; 1. The free market reform in China resulted in privatization that allowed respondents to become homeowners, and the ownership was viewed as part of family asset centered upon a sense of solidarity. 2. Although homeowners in multi-story houses were responsible to decorate interior spaces, the common features in using interior spaces were found: entrance had no thresholds; kitchen was small, lack of storage cabinets, tile-flooring; washers were installed inside bathroom; and newly built apartment didn't have proper space to store Korean fermented foods. It was observed that housing adaptation outweighed housing adjustment. Those who used to live in Chinese houses with indoor-wearing-shoes or Russian houses with indoor-wearing-slippers were receptive to the use of dining table and bed, and the community heating system discouraged the use of individual electric water heater because of high electricity cost. 3. In daily life, eating habit wasn't much changed to the Chinese style, meals were shared, dish sterilizer was popular, and Kimchi fridge wasn't used. Because of the influence of the Chinese culture, such Korean traditions as ancestral rites and bedroom allocation tradition faded away, but traditional family values remained unchanged. In conclusion, Korean Chinese people experience normative housing deficits and adaptation selectively incurred. It's implied that residential design meets the needs resulting from the dual culture in terms of cultural assimilation and acculturation.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.513-520
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• 2018

Since Paris Climate Change Conference in 2015, many policies to reduce the emission of greenhouse gas have been accelerating, which are mainly related to renewable energy resources and micro-grid. Presently, the technology development and demonstration projects are mostly focused on diversifying the power resources by adding wind turbine, photo-voltaic and battery storage system in the island-type small micro-grid. It is expected that the large-scaled micro-grid projects based on the regional district and town/complex city, e.g. the block type micro-grid project in Daegu national industrial complex will proceed in the near future. In this case, the economic cost or the carbon emission can be optimized by the efficient operation of energy mix and the appropriate construction of electric and heat supplying facilities such as cogeneration, renewable energy resources, BESS, thermal storage and the existing heat and electricity supplying networks. However, when planning a large residential town or city, the concrete plan of the energy infrastructure has not been established until the construction plan stage and provided by the individual energy suppliers of water, heat, electricity and gas. So, it is difficult to build the efficient energy portfolio considering the characteristics of town or city. This paper introduces an energy mix optimization(EMO) method to determine the optimal capacity of thermal and electric resources which can be applied in the design stage of the real large-scaled residential town or city, and examines the feasibility of the proposed method by applying the real heat and electricity demand data of large-scale residential towns with thousands of households and by comparing the result of HOMER simulation developed by National Renewable Energy Laboratory(NREL).

• Journal of the Korean Society for Marine Environment & Energy
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• v.13 no.1
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• pp.43-46
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• 2010

As one of the methods for recycling the FRP used for the small and medium-sized waste ships, separation of the roving layer from the mat has some merit in a sense of the recycling energy and the environmental effects. Similar characteristics between the roving and the mat make the mechanically automatic differentiation difficult. They, however, contain different ratio of the resin and the glass and the thickness. In this study photo physical differentiation between the two layers has been made using (1) boiling concentrated sulfuric acid which can dissolve the resin in the FRP layer and (2) hydrogen fluoride(HF) solution which can reacts with $SiO_2$ fragments of the glass. Furthermore coloring the FRP sample with water-soluble dye following the HF treatment makes the roving layer more distinguishable photophysically. The implementation of HF treatment has been successfully tested in this study.

• International Journal of Highway Engineering
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• v.9 no.4
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• pp.55-63
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• 2007

Deformational characteristics of subgrade soils are important properties in the mechanistic analysis and design of pavement system. In this study, to evaluate the effect of specimen construction methods on deformational characteristics of subgrade soils in Korea, resonant column tests were performed for specimens constructed by various methods. Specimen construction method affected to the modulus value but the variation in the normalized modulus reduction curve was almost identical. The effects of specimen construction method on modulus are decreased with increasing confining pressure. The average maximum variation in the modulus value with different specimen construction methods was estimated as 16.8%. The differences in the modulus value of the specimens with same water content and dry density conditions that made by gyratory compaction and impact compaction were very small within 5.2%. The impact compaction method was proposed as a specimen construction method for determining the design input parameter testing considering that impact compaction method is much simpler and require less expensive specimen construction equipment and setup than gyratory compaction method.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.12
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• pp.152-158
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• 2001

In this paper, we have developed an electro discharge machine for micro drilling driven by a voice coil actuator. Because the voltage signal of the electro-discharging circuit shows a lot of peaks and valleys, the active type low-pass filtering technique is adopted to get the average of the signal. Since the motion of the voice coil is precisely controlled by the error value between the object voltage value and the measured one, it is possible to prevent the mechanical contact between the rotating electrode and the workpiece and to maintain the appropriate machining conditions during the process. The electro-chemical machining technology was also adopted to make small diameter electrodes. Pure water is used as a dielectric. The machining procedure is performed to verify the feasibility of the developed system. It takes about 10 seconds to drill the ${\phi}m$100${\mu}m$ hole to the 100${\mu}m$ thickness stainless steel plate. The machining time depends on the values of the resister and the capacitor. There may exist the optimal values of time constant and the tendency is displayed In the appendix.

• Korean Journal of Pharmacognosy
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• v.36 no.3 s.142
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• pp.240-244
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• 2005

The methanol extract of the seed of Myristica fragrans (myristicaceae) demonstrated a potent inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2(melanoma), XF498 (central nerve system) and HCT-15(colon). The MeOH extract was fractionated into three portions by serial solvent partition i,e., EtOAc soluble part, BuOH soluble part and remaining water layer. Among them, the EtOAc soluble part of the extract demonstrated a potent inhibition on the proliferation of cultured human tumor cells, Bioassay-guided fractionation of the EtOAc soluble part led to the isolation of six lignan constituents, i.e., safrole(1), machilin A (2), licarin B (3), macelignan (4), mesodihydroguaiaretic acid (5) and myristargenol A (6) as well as a large amount of myristic acid as active ingredients. Structures of the isolated active components (1-6) were established by chemical and spectroscopic means.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.652-664
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• 2008

In this study, a Hazard Analysis Critical Control Point (HACCP) plan was developed for the sanitary mass production of commercial Korean rice cake products (Gaepidduk, Injulmi, and Julpyon). The microbiological properties of manufacturing flow were evaluated in order to develop the HACCP Plan. The moisture contents of the rice cakes ranged between 36.2${\sim}$55.3%, whereas the water activity of all samples ranged between 0.954${\sim}$1.0. Microorganisms testing was conducted during various phases of the product flow of Korean rice cake preparation, and included assessments of food equipment, work environment, and cooking employees on a small scale. During the manufacture of Injulmi, Julpyon and Gaepidduk, CCPs were purchasing & storage, steaming and cooling, molding, and holding in the A and B manufactories. At the critical limit of CCPs, storage was conducted below at $5^{\circ}C$ in soybean powder, oil, and paste with redbeans. The steaming process was conducted above at $99^{\circ}C$ for 40 min. Cooling and holding processes were conducted for 2 hours below at $15^{\circ}C$. The molding process included sanitary education for foodhandlers and training for operators. Thus, certain prerequisite programs had to be implemented prior to the implementation of the HACCP system. High levels of bacterial contamination were detected in the aprons worn to work by some employees. Additionally, periodic sanitary education for foodhandlers and training for operators or managers was required. Cross contamination by materials was expected at the place where materials were processed or stored.