• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1608-1610
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• 2000

In this work, the effect of annealing on physical and electrical properties of XLPE cable insulation was investigated. One sample was non-annealed and the other two samples were treated under air circulated oven at 80$^{\circ}C$ for five and ten days. In the DSC patterns of annealed specimen, new peaks appeared at near 80$^{\circ}C$ as a proof of thermal history. The degree of crystallinity increased by annealing effect. In the FT-IR spectrums, the change of absorbances to acetophenone and cumyl alcohol were observated according to the radial direction of cable insulation. They slowly diffused into both semi-conductive layer of the cable in proportion to annealing time and lastly led to near equilibrium state through cable insulation. The AC breakdown strength did not increased but the values were stabilized by effects of crystallinity and diffusion of by-products.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.3
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• pp.152-158
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• 2016

The bonding characteristics of MLCCs (multi layer ceramic capacitor, C1608) lead-free solder (SAC305) joints were evaluated through thermal shock test ($-40^{\circ}C{\sim}125^{\circ}C$, total 1,800 cycle). After the test, IMCs( intermetallic compounds) growth and cracks were verified, also shear strengths were measured for degradation of solder joints. In addition, The thermal stress distributions at solder joints were analyzed to compare the solder joints changes before and after according to thermal shock test by FEA (finite elements analysis). We considered the effects of IMCs growth at solder joints. As results, the bonding characteristics degradation was occurred according to initial crack, crack propagations and thermal stress concentration at solder-IMCs interface, when the IMCs grown to solder inside.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.92.2-92.2
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• 2012

조선(朝鮮)의 혼상(渾象)은 세종대(世宗代, 1418~1450)에 처음 제작되었다. 그 후 중종대(中宗代, 1506~1544)와 명종대(明宗代, 1545~1567)에 이를 보수를 하고, 선조대(宣祖代, 1567~1608)에 중수되었으나 현존하지 않고 있다. 민간에서 제작한 혼상은 16세기에 만든 도산서원의 혼상 유물이 유일한 것이다. 그 후 18세기에 만들어진 홍대용(洪大容, 1731~1783)의 혼상의(渾象儀)는 문헌으로만 전해지고 있다. 17세기 이전에 만들어진 혼상은 구법(舊法) 천문도에 의해 만들어졌지만, 17세기 이후에는 서양 과학의 유입으로 신법(新法)의 별자리를 사용하고 있다. 중국과 일본의 현존하는 혼상 유물 중에는 신법 별자리로 표기되어 있으며, 조선 후기 조선의 유물 가운데 평혼의(平渾儀) 유물은 신법의 별자리를 활용하고 있다. 최근 국내에서 복원한 혼상들은 구법 천문도로 제작되어왔다. 이 연구에서는 1861년 남병길(南秉吉, 1820~1869)이 저술한 조선의 신법을 대표할 수 있는 성표(星表)인 "성경(星鏡)"의 별자리를 활용하여 혼상을 제작하였다. 혼상구(渾象球)에는 적도좌표(赤道座標)와 황도좌표(黃道座標)를 함께 표기한 경선(經線)과 위선(緯線)을 각각 $30^{\circ}$ 간격으로 표기하였다. 또한 적도환(赤道環)에는 12궁(宮)을 표기하였고, 황도환(黃道環)에는 $15^{\circ}$ 간격으로 24기(氣)를 표기하였다. 별을 표기할 때 성경에 제시한 밝기와 같이 6등급으로 나누어 별의 크기를 제작하였다. 남병길의 "성경" 별자리를 활용한 혼상 제작으로 신법 별자리의 천상(天象)에 대한 이해와 연구 모델로 활용할 수 있게 되었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1608-1615
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• 1999

In this study, we investigate the inter cell interference of LMDS(Local multipoint Distribution Service) system cell in LMDS system design process. There are several interference sources in LMDS system but we consider co-channel adjacent interference, cross-polarization interference, tx/rx interworking interference as three major factors. As the summation of each interference, C/N is keep 19 dB in 2km range but decreased gradually over 2km. Based on theoretical results, we process the experimental test and get results that C/I=20 dB have to be maintained to transmit the data successfully under rain fall attenuation condition. This experiential results are similar to the theoretical analysis results we examined.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1608-1614
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• 2009

In recent days, the study of urban regeneration has been conducting with purposeful and sincere intent starting out with the residential environment improvement works. Within the range of urban regeneration, the low-cost housing technology means development of totally-integrated housing technology that may be applied to the regeneration project, especially for the rundown areas where infrastructure facilities in the urban zone have been degraded and obsoleted. In line with this, among many and varied methods in order for realization of the low-cost housing as a part of urban regeneration project, this study should like to propose an improvement methods of the key technologies in relation to the construction works by type of work with which construction costs (directing cost) would be reduced. And, in order to elicit the method for element technology that has been developed and improved in the most optimal manner centering on the selected construction work by the type of work, the researcher conducted comparative review of summary of element technologies related to the construction works concerned, characteristics, and construction method thereof. In particular, the researcher investigated the expenses (construction cost and labor cost), constructions (contractibility and productivity), safety, quality of works, and the technical status in environmental aspects, and the researcher also conducted analyses and evaluations thereof.

• Proceedings of the KIEE Conference
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• 2004.07c
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• pp.1605-1608
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• 2004

Single phase $CuInS_2$ thin film with a highest diffraction peak (112) at a diffraction angle ($2{\theta}$) of 27.7$^{\circ}$ was well made by SEL method at annealing temperature of 250 $^{\circ}C$ and annealing hour of 60 min in vacuum of $10^{-3}$ Torr or in S ambience for an hour. And the peak of diffraction intensity at miller index (112) of $CuInS_2$ thin film annealed in S ambience was shown a little higher about 11 % than in only vacuum. Single phase $CuInS_2$ thin films were appeared from 0.85 to 1.26 of Cu/In composition ratio and sulfur composition ratios of $CuInS_2$ thin films fabricated in S ambience were all over 50 atom%. Also when Cu/In composition ratio was 1.03, $CuInS_2$ thin film with chalcopyrite structure had the highest XRD peak (112). And lattice constant a and grain size of the thin film in S ambience were appeared a little larger than those in only vacuum. The largest lattice constant of a and grain size of $CuInS_2$ thin film in S ambience was 5.63 ${\AA}$ and 1.2 ${\mu}$m respectively. And the films in S ambience were all p-conduction type with resistivities of around $10^{-1}{\Omega}cm$.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.5
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• pp.1599-1608
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• 2014

This study is to suggest specialty contractors with countermeasures to construction orders falling off, one of the construction business indicators for the construction industry, by analyzing the impact of dwindling construction orders to business performance indicators of specialty contractors as well as identifying inter-relationships between those performance indicators. For specialty contractors of civil construction, it is analyzed that their current ratio is significantly affecting obtention of construction orders, which in turn greatly affecting the ratio of owner's equity. It seems that the amount of construction orders has a direct relationship with the corporate stability. Therefore, this type of specialty contractors are determined to be able to obtain more orders for construction by improving current ratio.

• Journal of Environmental Science International
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• v.24 no.12
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• pp.1601-1608
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• 2015

This study evaluates heavy metal(Cu and Cr) adsorption characteristics produced from food waste charcoal extracted in an optimal operation condition after analyzing activated charcoal of iodine adsorption and heavy metals that derived from an activation process of carbide by the developed by-products of food waste treatment facility using the methods from previous studies. As experiment apparatus, this study used a tube-shaped high temp furnace. The mixing ratio of by-products of food waste treatment facility, carbide, and activation component($ZnCl_2$) was 1:1. The experiment was proceeded as adjusting the activation temperature from 400 to $800^{\circ}C$ and activation time from 30 to 120 minutes. The optimal activation condition for iodine absorption was 90 minutes at $700^{\circ}C$ and by using the produced food waste charcoal, this study conducted an experiment on absorption of heavy metals (Cu and Cr) as changing pH of artificial wastewater and stirring time. As a result, pH 7 showed the highest heavy metal decontamination ratio and in terms of stirring time, it revealed balance adsorption after 10 minutes. This result can be particularly applied as basic data for recyclability of high concentration organic waste, by-products of food waste treatment facility, as an food waste charcoal.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.11
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• pp.1598-1608
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• 2013

An optimum dietary carbohydrate content is important for maximum fish growth. In this study, we fed Wuchang bream (Megalobrama amblycephala) with either control diet (30.42%) or high carbohydrate diet (52.92%) for 90 d. Fish were fed to apparent satiation three times daily in an aquarium with automatic temperature control and circulated water. Growth performance, plasma biochemical parameters, hepatic morphology and enzyme activities were determined. It was shown that compared to fish fed control diet, fish fed high carbohydrate diet had higher plasma triglyceride and cortisol levels for d 90, and lower alkaline phosphatase level for d 45, lower hepatic superoxide dismutase and total antioxidative capacity for d 90, higher malondialdehyde for d 45 and glycogen content for d 45 and 90 (p<0.05). Histological and transmission electron microscopy studies showed that hepatocytes of fish fed high carbohydrate diet contained large lipid droplets, causing displacement of cellular organelles to periphery of hepatocytes. The relative level of hepatic heat shock protein 70 (HSP70) mRNA of Wuchang bream fed high carbohydrate diet was significantly higher than that of fish fed the control diet for 90 d (p<0.05). These changes led to decreased specific growth rate and increased feed conversion ratio (p<0.05). Upon hypoxia challenge, fish fed high carbohydrate diet had higher cumulative mortality than those fed the control diet (p<0.05). These results suggested that high dietary carbohydrate (52.92%) was detrimental to the growth performance and health of Wuchang bream.

• Korean journal of food and cookery science
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• v.29 no.4
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• pp.377-385
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• 2013

The changes in ingredients, seasonings and cooking methods of Japchae in Korean cook books published from the 1600s to the 1960s were investigated in this study. Japchae was a royal dish enjoyed by Kwanhaegun of Joseon Dynasty and interesting historical story is contained in it. Kwanghaegun Ilgi in 1608 showed that Japchae was Kwanghaegun's favorite dish. Therefore, it has been thought that Japchae was created in the 17th century. Wonhaengeulmyojeongrieugye in 1796 described bellflower Japchae and mungbean sprout Japchae. The traditional Japchae was made without glass noodle called dangmyeon. Eumsikdimibang in 1670 first introduced traditional Japchae, which was made with 20 different ingredients and then served with topping sauce made of pheasant broth, strained soybean paste and wheat flour. Japchae in Kyugonyoram(1896) was prepared by mixing mungbean sprout, watercress, gonjasoni, tripe and yukhwe with mustard. The current style Japchae with glass noodle first appeared in the 1920s and became popular in the 1950s because the traditional Japchae was described in cook books until the 1940s. There were two ways of preparing current style Japchae. Yijogungjeongyoritonggo in 1957 described Japchae was made by mixing the boiled glass noodle with other ingredients and seasonings together. On the other hand, Japchae in Urinaraeumsikmandeuneunbeob(1960) was prepared by seasoning first with other ingredients, and then mixing boiled glass noodle. A variety of ingredients - vegetables, mushrooms, meat, fish, pheasant, beef tong, sea cucumber, gonjasoni and pear - has been used to prepare Japchae. Japchae has been seasoned with ginger, soy sauce, black pepper, sesame salt, sesame oil, oil, leek, garlic, salt, sugar, vinegar and mustard. Egg strips, pine nut, thin strips of Shiitake and stone mushroom, red pepper threads, Chinese pepper(cheoncho), black pepper and ginger were used for garnishing.