• 열처리공학회지
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• 제9권3호
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• pp.177-186
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• 1996

Surface alloying of Ti alloy by $CO_2$ laser is able to produce few hundred micrometers thick TiN or TiC surface-alloyed layer with high hardness on the substrate by injecting reaction gas($N_2$ or $CH_4$). Laser surface alloying by means of process control is in many applications essential in order to obtain predictable hardening layer. This research has been investigated the effect of such parameters on TiN and TiC gas alloying of Ti-6Al-4V alloy by $CO_2$ laser. The maximum surface hardness of TiN layer was obtained 1750Hv on the conditions of 0.8kW laser power, 0.8m/min scanning speed and 100% $N_2$ atmosphere. However, the maximum hardness of TiC formation layer after laser treatment was about 630Hv. As scanning speed was increased, the hardness and depth of these layers were decreased at constant laser power.

• 한국식생활문화학회지
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• 제18권6호
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• pp.515-526
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• 2003

The object of this study was to investigate the relationship between the eating habits of high(4th, 5th, 6th) grade elementary school students and parental behavior characteristics(affection, rational guidance, overprotect and neglect). The parenting behavior scale and demographic variables, eating habits and food frequency were administered to the subjects. In this investigation, the subjects were 396 boys and 337 girls in Chunju city in Korea, 50.1% of the mothers was in the age from 35 to 39 years and 57.8% of the mother had an occupation. Data were analyzed by using a SPSS PS package. Significant differences and correlation among variables were determined by the frequency, $x^2-test$ and pearson's correlation coefficient. Eating habits was significantly influenced by mother's employment status, but was not affected by the levels of mother's education and income. Parental behavior characteristics was significantly related to the children's snacks habits(p<0.05, p<0.01), but have no connection with dietary habits and the eating out. The survey revealed higher percentage of the children who had taken affectionate, reasonable and positively reinforced child care, answered they enjoy meals and the other groups answered they did not. Also frequency of having soup, green vegetables, fruits, dairy products had positive relationship with affective, reasonable rearing attitude, but negative relationship with neglective rearing attitude. And the survey showed children who were reared in overprotect had chocolate, candy and the like in large quantities.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.536-538
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• 2001

국내에서는 전력산업의 규제가 점차 완화되면서 전력시장은 새로운 틀이 형성되어지고 있다. 전력시장의 구조개편후 각 전력회사들은 그들의 판매수익을 높이기 위하여 행동하게 될 것이다. 즉 그들의 부하를 적절하게 조절함으로써 한계비용이 평균비용보다 낮게 유지되도록 하여 이윤극대화를 추구해 나갈 것이다. 따라서 전력회사들은 수요측의 관리가 과거 어느 때 보다 필요하게 될 것이며, 어떻게 하면 부하곡선의 피크치를 억제할 것인지 생각하게 된다. 이러한 것을 해결하기 위해 전력회사들은 그들의 소비자 대부분을 수요관리 프로그램에 참여시키 부하관리를 할 것이며 이를 통해 피크치 부하를 억제시켜 한계비용을 줄이려할 것이다. 소비자들을 수요관리 프로그램에 참여토록 유도하기 위하여 전력회사는 여러 가지 인센티브를 제공하게 되는데, 소비자들은 이러한 인센티브를 받아 프로그램에 참여할 것인지를 선택하게 된다. 본 논문에서는 전력회사가 수요관리 프로그램을 실행할 때 어떤 효과를 얻게 되고 참여자들이 느끼는 순이익은 어떻게 될지를 고려하게 될 것이다. 이러한 것들은 전력회사 입장에서는 수요관리 프로그램을 실행하는 것이 그들에게 이익을 가져다 줄 것인지를 말해주며 소비자들은 그들의 프로그램에 지속적으로 참여할 것인지를 선택하게 될 것이다.

• 열처리공학회지
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• 제8권1호
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• pp.44-52
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• 1995

The specimen for laser hardening have been carried out using SM45C which is coated with black paint or graphite for better absorption. Segmented mirror was used in order to produce a square beam ($10{\times}10mm$) at the surface with a homegeneous intensity distribution across the beam. $CO_2$-Laser power was changed from 2kW to 4kW and transfer velocity was varied from 0.1m/min to 2.0m/min. The maximum hardness and case depth of SM45C steel are 790Hv and 1.5mm by laser hardening. When the surface of specimens was melted during laser hardening. the surface hardness of SM45C steel was decreased. The surface hardness of 2 layer coated specimen(black paint: $15.4{\mu}m$, graphite coating: $9.5{\mu}m$) was increased than that of 1 layer coated specimen. It is desirable to prepare 2 or more coating layer on the steel surface in order to sufficient case depth and hardness in laser hardening. The graphite coating on the specimen surface was obtained more uniform temperature distribution than black paint coating in laser hardening process.

• 한국환경생태학회지
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• 제23권2호
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• pp.143-150
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• 2009

변산반도 국립공원 신선봉지역의 능선부 식생구조를 파악하고자 능선부에 방형구($400m^2$) 14개를 설정하여 식생을 조사하였다. 식물군집을 분류한 결과 14개 조사구는 굴참나무졸참나무군집, 개서어나무군집의 2개 군집으로 분류되었다. 신선봉지역의 능선부는 대부분 굴참나무와 졸참나무가 우점하고 있었으며 해발고가 높은 일부지역에 개서어나무가 우점하는 임분이 나타나고 있었다. 수종간의 상관관계에서는 굴참나무와 말오줌대는 부의 상관이 인정되었고, 때죽나무와 졸참나무, 말오줌대와 철쭉, 피나무, 쪽동백나무와 산딸나무, 철쭉과 서어나무, 산딸나무와 피나무는 정의 상관이 인정되었다. 조사지의 군집별 종다양성 지수는 $1.237{\sim}l.497$의 범위로 다른 국립공원들의 식생구조에 비하여 다소 높게 나타났다.

• 한국문헌정보학회지
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• 제27권
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• pp.99-124
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• 1994

This study examines the establishment of Sea-po (서포) in the opening period of Korea at the end of the 19th century. The role they played, the particular situations and their geographical characteristics are researched, The earliest sea-po was Koh-je-hong sea-po, which was established in Tae­kwang-kyo at the end of 1880s. Around 1905, a specialised book distribution system was set up with establishement of Chu-han-yung book store, Kim-sang-man book store, Jesuit book store, Tae-dong su-si, Kae-myung sea-kwan, Tong-wha seo-kwan. The owners of the seo-pos were pioneers in introducing modern culture with nationalistic consciousness, although they were primarily businessmen and their social origins varied. The primary role of seo-pos was selling a variety of books but some combined printing and publication of books as well. It seems that publication business took roots around 1908, though it is difficult to know the accurate dates of first attempts. Some sea-pas offered book rental services for poor people who could not easily afford to purchase books. A certain amount of deposit had to be paid to benefit from the services. Jesuit Bookstore in Pyungyang had a library facility with a large stock or books in the same building open to public for free. These sea-pas started mainly in Seoul and Pyungyang, which were traditional centers for economic and cultural affairs. Early introduction of foreign cultures and commercial developments in these areas contributed to the establishment of sea-pos. The sea-po which took charge of book distribution in the provinces was set up around 1906. One of the important findings of this study is that the geographical distribution of sea-po shows the following three characteristics. First is that the area such as Seoul, Taegu and Chunju were the traditional centers of publishing culture from which Pang­gak-bon(방각본) emerged. Second characteristic is Pyungyang and the surrounding Pyungbuk province, and harbors like Inchon and Pusan, which had the benefits of early spread of modem cultures. Third characteristic is Kaesung and the surrounding Hwanghae province which bridged Pyungyang and Seoul. The reception of foreign cultures stimulated the commercial spirits traditionally attributed to Kaesung to establish sea-pas most actively.

• 대한공간정보학회지
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• 제16권1호
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• pp.13-21
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• 2008

본 논문에서는 금강수계의 미호천을 대상으로 GIS를 이용, 2010년을 대상으로 장래수질을 예측하였다. 오염총량관리 기본계획에서 제시된 자료를 기반으로 미호천으로 유입되는 지류별 수계에 대하여 재계산하여 각 수계별 오염부하량을 산정하였으며 이들 정보를 활용하여 지류별 농도를 계산한 다음 미호천의 수질모의를 실시하였다. 수질모의는 대표적인 하천수질 모형인 Qual2E 모형을 사용해서 BOD, TN, TP 등의 대표적인 수질인자에 대한 모의를 실시 하였다. 수계별 오염부하량을 산정한 결과 도시지역을 포함한 무심천 및 보청천의 부하량이 높게 나타남을 알 수 있었고 미호천 전체 수질은 청주 하수처리장의 영향을 직접적으로 받는 것으로 나타났다. 대상유역에서의 효율적 수질관리와 오염총량제에서 제시한 목표수질을 달성하기 위해서는 하수처리장의 고도처리화가 먼저 달성되어야 함을 알 수 있었고, 그 외에도 무심천으로 공급되는 농업용수의 유량을 증가시켜 이를 수질희석의 용도로 사용하는 방안에 대해서 모의를 실시함으로써 수질기준을 만족할 수 있는 적정유량을 산정하여 제시하였다.

• 한국응용곤충학회지
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• 제5_6권
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• pp.59-63
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• 1968

본 논문은 1963-1965년 사이에 구기자 혹응애의 생태에 관하여 조사 관찰한 결과의 일부를 보고한 것이다. (1) 구기자 혹응애의 기주식물은 순기자나무 까마중 및 고추 등이다. (2) 이동과 전파는 물리적인 매개체에 의하며, 풍향은 이동과 전파에 영향이 크다. (3) 1자당 산난수는 평균 $28.5\pm0.499$개이고, 란기간은 평균 $7.0\pm0.447$일이다. 유충기문은 평균 $4.33±\pm0.667$일이다. (4) 식입 후 경과일별 충영의 크기는 1일째는 평균 $290.5\pm0.3415\pm$ 이며, 25일째는 평균 $3260.5\pm0.5157\mu$이다. (5) 성충기간은 25-30일이고 식입 후 산난일은 6일 이다. (6) 연발생회수는 6-7회이며, 성충태로 충영내에서 월동하여 5월 하순에 제1회 성충이 나타난다.

• Journal of the Korean Data and Information Science Society
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• 제28권4호
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• pp.819-829
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• 2017

가격의 추세가 형성되면 그 방향으로 진행하려는 price momentum 현상은 여러 국가의 거의 모든 주식, 채권 및 통화 시장에서 관찰되고 있다. KOSPI200선물을 대상으로 거래량 패턴과 일중 price momentum을 분석하였다. KOSPI200선물에서 장이 열릴 때와 닫힐 때 거래량이 집중되는 U자형 거래량 패턴이 관찰되었다. 9시 10분의 가격 수익률이 9시 시초가 대비 양 (+)이면 매수, 음 (-)이면 매도 진입하여 종가에 청산하는 전략의 유효성을 확인함으로써 일중 price momentum 현상이 존재함을 확인하였다. 또한, 9시부터 9시 10분까지 수익률이 점점 증가되는 J자형 가격 패턴 경우는 그렇지 않은 패턴 경우보다 price momentum 현상이 더 강함을 분석하였다. J자형 가격 패턴 여부를 판단하는 방법으로 DTW 분석 방식을 사용하였다. DTW 분석은 일중 가격 움직임을 예측하는데 유용함을 확인할 수 있었다.

• 한국조경학회지
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• 제28권3호
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• pp.105-115
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• 2000

The purpose of paper is to investigate the characteristics of regulations on landscape management of historic city of Kyongju in Korea, compared with those of Nara in japan to answer the research question that what is the regulative characteristics of landscape management of historic city in Korea. We have analyzed the three laws of the two country - Urban Planning Law, Cultural Assets Protection law, and Building Law. This research has been done in terms of regulative systems of the two country and articles, ordinances, and bylaws on landscape managements of historic city Major components of urban historic landscape management are goals and devices of preservation, preserving actor, authorized actor permitting major planning change, regulatory power on landscape development, and backgrounds of enacting regulations. From this research, we have fond the fact that 1) Kyongju City has general and implicit objectives of landscape management based on conservation of natural environment while Nara City has concrete objectives of lansdscape management, 2) Kyongju City has no regulations on landscape planning while Nara City has systematic planning measures such as designation of landscape management district, planning for preservation of historic landscape, and planning for establishing urban landscape, 3) In an application of landscape management district, Kyongju City designate the district based on the general principle of urban planning district while nara City designate it in a more detailed manner such as district of preservation of historic landscape, district of landscape establishment, and district of building agreement. 4) Kyongju has no legal actor in implementation and management of historic landscape plan while Nara City has administrative organization and procedures, including citizen participation, public hearing, and voluntary participation, and 5) Kyongju City does not operate the consultation committee on landscape management just like Nara City operating. This research results will provide us the remedial insights for landscape preservation of such Korean historic city as Kongju, Puyo, and Chunju. Since our research is focused on the limited area of preserving landscape in historic cities in korea and Japan we need to study sociocultural issues on preserving urban historic landscape more in depth in the future.