• Title/Summary/Keyword: Integral

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Analyzing the Implement System Shift of Land Policies (토지정책 추진체계 변화 연구)

  • Kim, Mi-Suk;Yun, Jeong-Ran;Park, Sang-Hak
    • Land and Housing Review
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    • v.2 no.4
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    • pp.439-452
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    • 2011
  • The goal of this research is to suggest the desirable directions of the land policies implement system based on analysis of existing those of Korea with the paradigm shift of land policies. We classify the land policies into land ownership, land use, land development and land management ones, and then analyze their implement system characteristics. The results are follows : firstly, the land policies implement systems have been set to large scale and rapid development. Secondly, although the systems have been specialized by their areas, the comprehensive manage systems for the harmony between development and conservation are lacking. Thirdly, the parts of the central government powers related to land use has been hand covered to local governments. And the participations of residences private companies have enlarged in the land development. Fourthly, the purposes of the information management on land use have been changed from tax collection into planned land use, but the information management has not met the need of planned land use. This study shows that firstly, the implement system focusing on large development projects might be no longer effective because of high possibility of the property prices stabilization, so moderately small ones must be found. Secondly, the system cope with the climate change and to realize the efficient utility of land is needed. Thirdly, it is necessary to take the actual measures to participate a variety of subjects. Fourthly, the system modification of the land information manage system as land policies infra is also needed to establish integral land policies.

Characterization of SiC nanowire synthesize by Thermal CVD

  • Jeong, Min-Uk;Kim, Min-Guk;Song, U-Seok;Jeong, Dae-Seong;Choe, Won-Cheol;Park, Jong-Yun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.74-74
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    • 2010
  • One-dimensional nanosturctures such as nanowires and nanotube have been mainly proposed as important components of nano-electronic devices and are expected to play an integral part in design and construction of these devices. Silicon carbide(SiC) is one of a promising wide bandgap semiconductor that exhibits extraordinary properties, such as higher thermal conductivity, mechanical and chemical stability than silicon. Therefore, the synthesis of SiC-based nanowires(NWs) open a possibility for developing a potential application in nano-electronic devices which have to work under harsh environment. In this study, one-dimensional nanowires(NWs) of cubic phase silicon carbide($\beta$-SiC) were efficiently produced by thermal chemical vapor deposition(T-CVD) synthesis of mixtures containing Si powders and hydrocarbon in a alumina boat about $T\;=\;1400^{\circ}C$ SEM images are shown that the temperature below $1300^{\circ}C$ is not enough to synthesis the SiC NWs due to insufficient thermal energy for melting of Si Powder and decomposition of methane gas. However, the SiC NWs are produced over $1300^{\circ}C$ and the most efficient temperature for growth of SiC NWs is about $1400^{\circ}C$ with an average diameter range between 50 ~ 150 nm. Raman spectra revealed the crystal form of the synthesized SiC NWs is a cubic phase. Two distinct peaks at 795 and $970\;cm^{-1}$ over $1400^{\circ}C$ represent the TO and LO mode of the bulk $\beta$-SiC, respectively. In XRD spectra, this result was also verified with the strongest (111) peaks at $2{\theta}=35.7^{\circ}$, which is very close to (111) plane peak position of 3C-SiC over $1400 ^{\circ}C$ TEM images are represented to two typical $\beta$-SiC NWs structures. One is shown the defect-free $\beta$-SiC nanowire with a (111) interplane distance with 0.25 nm, and the other is the stacking-faulted $\beta$-SiC nanowire. Two SiC nanowires are covered with $SiO_2$ layer with a thickness of less 2 nm. Moreover, by changing the flow rate of methane gas, the 300 sccm is the optimal condition for synthesis of a large amount of $\beta$-SiC NWs.

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Development of a Solar Concentrator having the Reflecting Surface with the 2m Class Diameter (직경 2m급 반사면을 가지는 태양열 집광 장치 개발)

  • Cha, Jung-Won;Lee, Dong-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.13 no.4
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    • pp.75-81
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    • 2008
  • Purpose: To develop a solar concentrator having the reflecting surface with the 2m class diameter. Methods: In order to make the reflecting surface for the solar concentrator, the shape of the reflecting surface sector is required. So, first, we induced the formula that can produce this shape. After that, using Delphi 6.0 language, we developed a program which uses this formula and produces the shape and the numerical data of the reflecting surface sector with the input variables such as the external diameter of the reflecting mirror, the reflecting mirror's radius of curvature at the paraxial range, the number of reflecting mirror sector, the size of the center hole of the reflecting mirror, and the interval of the output data. Results: This program, which was developed to produce the shape and the numerical data of the reflecting surface sector, enables us to see the shape of sector on the monitor and to save the numerical data files for the shape of sector. As a result, the user of this program can easily access the numerical data of the reflecting surface sector. Conclusions: Developing the program which produce the reflecting surface sector used to make the reflecting surface of the solar concentrator, we could succeed in making the prototype products by applying it to the development of the real solar concentrator with the diameter of the 2m class.

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Development of Remote Reld Testing Technique for Moisture Separator & Reheater Tubes in Nuclear Power Plants (원자력발전소 습분분리재열기 튜브 원격장검사 기술 개발)

  • Nam, Min-Woo;Lee, Hee-Jong;Kim, Cheol-Gi
    • Journal of the Korean Society for Nondestructive Testing
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    • v.28 no.4
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    • pp.339-345
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    • 2008
  • The heat exchanger tube in nuclear power plants is mainly fabricated from nonferromagnetic material such as a copper, titanium, and inconel alloy, but the moisture separator & reheater tube in the turbine system is fabricated from ferromagnetic material such as a carbon steel or ferrite stainless steel which has a good mechanical properties in harsh environments of high pressure and temperature. Especially, the moisture separator & reheater tubes, which use steam as a heat transfer media, typically employ a tubing with integral fins to furnish higher heat transfer rates. The ferromagnetic tube typically shows superior properties in high pressure and temperature environments than a nonferromagnetic material, but can make a trouble during the normal operation of power plants because the ferrous tube has service-induced damage forms including a steam cutting, erosion, mechanical wear, stress corrosion cracking, etc. Therefore, nondestructive examination is periodically performed to evaluate the tube integrity. Now, the remote field testing(RFT) technique is one of the solution for examination of ferromagnetic tube because the conventional eddy current technique typically can not be applied to ferromagnetic tube such as a ferrite stainless steel due to the high electrical permeability of ferrous tube. In this study, we have designed RFT probes, calibration standards, artificial flaw specimen, and probe pusher-puller necessary for field application, and have successfully carry out RFT examination of the moisture separator & reheater tube of nuclear power plants.

Three body problem in early 20th century (20세기초의 삼체문제에 관해서)

  • Lee, Ho Joong
    • Journal for History of Mathematics
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    • v.25 no.4
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    • pp.53-67
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    • 2012
  • Today, it is necessary to calculate orbits with high accuracy in space flight. The key words of Poincar$\acute{e}$ in celestial mechanics are periodic solutions, invariant integrals, asymptotic solutions, characteristic exponents and the non existence of new single-valued integrals. Poincar$\acute{e}$ define an invariant integral of the system as the form which maintains a constant value at all time $t$, where the integration is taken over the arc of a curve and $Y_i$ are some functions of $x$, and extend 2 dimension and 3 dimension. Eigenvalues are classified as the form of trajectories, as corresponding to nodes, foci, saddle points and center. In periodic solutions, the stability of periodic solutions is dependent on the properties of their characteristic exponents. Poincar$\acute{e}$ called bifurcation that is the possibility of existence of chaotic orbit in planetary motion. Existence of near exceptional trajectories as Hadamard's accounts, says that there are probabilistic orbits. In this context we study the eigenvalue problem in early 20th century in three body problem by analyzing the works of Darwin, Bruns, Gyld$\acute{e}$n, Sundman, Hill, Lyapunov, Birkhoff, Painlev$\acute{e}$ and Hadamard.

The Interesting Moving Objects Tracking Algorithm using Color Informations on Multi-Video Camera (다중 비디오카메라에서 색 정보를 이용한 특정 이동물체 추적 알고리듬)

  • Shin, Chang-Hoon;Lee, Joo-Shin
    • The KIPS Transactions:PartB
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    • v.11B no.3
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    • pp.267-274
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    • 2004
  • In this paper, the interesting moving objects tracking algorithm using color information on Multi-Video camera is proposed Moving objects are detected by using difference image method and integral projection method to background image and objects image only with hue area, after converting RGB color coordination of image which is input from multi-video camera into HSI color coordination. Hue information of the detected moving area are normalized by 24 steps from 0$^{\circ}$ to 360$^{\circ}$ It is used for the feature parameters of the moving objects that three normalization levels with the highest distribution and distance among three normalization levels after obtaining a hue distribution chart of the normalized moving objects. Moving objects identity among four cameras is distinguished with distribution of three normalization levels and distance among three normalization levels, and then the moving objects are tracked and surveilled. To examine propriety of the proposed method, four cameras are set up indoor difference places, humans are targeted for moving objects. As surveillance results of the interesting human, hue distribution chart variation of the detected Interesting human at each camera in under 10%, and it is confirmed that the interesting human is tracked and surveilled by using feature parameters at four cameras, automatically.

Analysis of pollutant mixing on the water surface in rivers with GPS floaters (GPS부자를 이용한 하천 표면에서의 오염물질 혼합 거동 해석)

  • Seo, Il Won;Park, Inhwan;Kim, Young Do;Han, Eun Jin
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.103-103
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    • 2015
  • 유류유출사고와 같이 하천 수표면의 흐름에 따라 이동 확산하는 부유성 오염물질의 혼합해석을 위해 많은 연구자들은 입자추적모형을 사용한 혼합모의를 수행해왔다. 입자추적모형에서 오염물질의 혼합은 평균 유속 분포에 의한 결정론적인 이동과 난류유동에 의한 무작위적인 혼합으로 나타내며, 난류혼합에 의한 수평확산은 난류확산계수로 조절한다. 따라서 표면흐름에 의한 난류확산계수의 산정을 위해 많은 연구자들은 부유성 입자를 이용한 실내실험을 수행하여 수평확산계수를 산정했고(Engelund, 1969; Cederwall, 1971), 최근에는 GPS의 발전으로 인해 해양영역에서 GPS를 장착한 표면부자를 활용한 확산실험을 통해 수평확산계수를 산정한 바 있다(Kjellson and $D{\ddot{o}}{\ddot{o}}s$, 2012; Alpers 등, 2013). 하천수질오염사고의 약 43.5%가 유류유출에 의한 것이며(환경부, 2013), 이에 따라 표면흐름에 의한 오염물질 혼합해석이 필요하나, 하천에서 수평확산계수 산정을 위한 현장실험연구는 부족한 상황이다. 따라서 본 연구에서는 낙동강 본류에서 GPS부자를 이용한 입자추적실험을 수행하여 표면흐름에 의한 확산계수를 산정했다. GPS부자를 이용한 입자추적실험은 낙동강의 강정고령보 하류와 구미보 하류의 각각 세 지점에서 수행되었다. GPS부자는 바람에 의한 교란을 최소화하기 위해 지름 10 cm의 구형으로 제작하였으며 시범테스트를 통해 입자의 주 궤적 변화가 크지 않은 지점에 GPS부자를 투입했다. GPS부자는 오염물질의 사고유출을 가정하여 한 지점에 투입했고 GPS부자 사이의 간섭을 최소화하기 위해 25 ~ 35개의 GPS부자를 이용했다. 표면흐름에 의해 이동하는 부자의 위치는 GPS에 시계열로 저장됐고 ADCP를 이용하여 실험당시의 수리량을 측정했다. 입자위치의 시계열자료로부터 GPS부자의 확산범위의 시간변화를 계산했고 단순 모멘트법을 이용하여 종, 횡 방향 확산계수를 계산했다. 그 결과, 종 방향 확산계수는 $0.003{\sim}0.041m^2/s$로 계산되었고 횡 방향 확산 계수는 $0.001{\sim}0.012m^2/s$로 계산되어, 흐름방향의 유속성분에 의한 확산이 지배적인 것으로 나타났다. 지류 합류부에서는 이송이 지배적인 혼합이 발생되었고(Pe>1) Pe의 증가에 따라 수평확산계수가 감소되었다. 25~35개 GPS부자 궤적의 앙상블 평균으로부터 계산한 Integral time scale은 모멘트법으로부터 계산한 종, 횡 방향 확산계수와 비례하는 것으로 나타나, Taylor(1921)의 이론과 일치했다. 또한 실험수로에서 수행된 기존연구결과와 비교한 결과, 하폭 대 수심비, 마찰항의 증가에 따라 수평확산계수가 증가하는 경향을 나타내었다.

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An Assessment of HIV/AIDS Knowledge, Attitudes, and Risk Perceptions among Korean Pharmacy Students (HIV/AIDS에 관한 국내 약학대학 학생들의 지식, 태도와 위험인식 평가)

  • Huh, Wan;Yang, Young-Mo;Jeong, Eun;Lee, Jieun;Je, Nam Kyung;Lee, Jae-Joon;Lim, Sung Cil;Choi, Eun Joo
    • YAKHAK HOEJI
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    • v.58 no.5
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    • pp.349-356
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    • 2014
  • With the advent of highly active anti-retroviral therapy (HAART), the perceptions of HIV therapy have changed from treating acute and terminal diseases to managing complex chronic diseases. Due to needs for specialists with professional knowledge on anti-retroviral therapies, pharmacists have been recognized as established and integral members in HIV multi-disciplinary care teams. Nevertheless, the roles of Korean pharmacists for HIV/AIDS therapy were highly limited. According to the transition of '2+4'-year pharmacy school curricula in Korea, it is necessary for pharmacy students to possess improved knowledge about and proper attitudes toward HIV/AIDS as future pharmacists. However, there have been little studies regarding the assessment of HIV/AIDS knowledge, attitudes, and risk perceptions of pharmacy students in Korea. Thus, this study was to examine Korean pharmacy students' knowledge levels, attitudes, and risk perceptions about HIV/AIDS and compare them according to pharmacy educational systems. The self-reported questionnaire was utilized to collect data. Total 238 students responded to the survey questionnaires. Most pharmacy students who participated in this study knew that the main transmission routes of HIV were unprotected sex, unscreened blood, occupational exposure, and intravenous drug use. However, they did not properly know post exposure prophylaxis for HIV. The pharmacy students under '2+4'-year curricula were more competent with treatment, care, counseling for HIV patients than those under 4-year curricula. Most pharmacy students thought that all healthcare students and professionals should receive mandatory HIV testings. The results from this study may contribute to developing new educational programs about HIV/AIDS. Additionally, further studies regarding the changes of Korean pharmacy students' attitudes and risk perceptions will need to be performed after they participate in these kinds of the programs.

Detection of Human Papillomavirus and Expression of MHC Class I in Laryngeal Squamous Cell Carcinoma (후두편평세포암종에서 Human papillomavirus의 검출과 주조직적합복합체(Major Histocompatibility Complex: MHC) Class I 발현양상)

  • Oh, Byung-Kwon;Hwang, Chan-Seung;Hong, Young-Ho;Kim, Hoon;Kim, Chun-Gil;Min, Hun-Ki
    • Korean Journal of Bronchoesophagology
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    • v.3 no.1
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    • pp.70-78
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    • 1997
  • The development of preneoplastic and neoplastic squamous cell proliferations of body sites such as the skin, female lower genital tract, and larynx is strongly associated with specific types of human papillomaviruses (HPV). Antitumor $CD^{8+}$ cells recognize peptide antigens presented on the surface of tumor cells by major histocompatibility complex (MHC) class I molecules. The MHC class I molecule is a heterodimer composed of an integral membrane glycoprotein designated the alpha chain and a noncovalently associated, soluble protein called beta-2-microglobulin( $\beta$ -2-m). Loss of $\beta$-2-m generally eliminates antigen recognition by antitumor $CD^{8+}$ T cells. We evaluated the expression of $\beta$-2-m as a potential means of tumor escape from immune recognition and the presence of HPV DNA as a cause of laryngeal squamous cell carcinomas (SCCs). Laryngeal SCCs (n=39) were analyzed for MHC class I expression by immunohistochemistry and for presence of HPV by in situ hybridization technique. The results were as follows : 1) HPV DNA was detected in 10 (25.64%) out of 39 cases in laryngeal squamous cell carcinomas. 2) MHC class I down-regulation (heterogenous and negative expression) in HPV positive lesions was higher than HPV negative lesions. 3) The expression of MHC class I was related to cellular differentiation regardless of T-stage and nodal involvement. In conclusion, HPV was thought to be the etiological factor of SCC of larynx, and we found that the down-regulation of MHC class I was a common phenomenon In laryngeal SCC and may provide a way for tumor cells to escape from immune surveillance.

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Current Status and Future Prospects of the Population Control Policy in Korea (출산조절정책의 현황과 전망)

  • 조남훈
    • Korea journal of population studies
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    • v.11 no.1
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    • pp.14-31
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    • 1988
  • The national family planning program in Korea, which was instituted as an integral part of the nation's economic development plans since 1962, has contributed greatly to a reduction in the fertility and population growth rate. The total fertility rate dipped from 6.0 births per women in 1960 to 2.0 in 1985, and the population growth rate rom 2.84 percent per year to 1.25 percent during the same period, while the contraceptive practice rate for the 15-44 married women increased from 9 percent in 1965 to 70 percent in 1985. Study findings indicate that the fertility reduction in the past 26 years is largely attributed to the virgorous implementation of the national family planning program, rising age at marriage, wide-spread use of induced abortion, and the changes in attitude regarding the value of children that came into being in the wake of the rapid socio-economic development over the period. Among the strengths of the national family planning program are the following : 1) a pluralistic system of program manageent with active participation of various government and voluntary organizations, 2) utilization of a large corps of family planning field workers to conduct face-to-face communication and motivation activities, 3) use of private physicians with government support to provide contraceptive services, 4) a systematic program management system including program planning of traget allocation, evaluation, and supervision with a broad MIS and award system, 5) numerous incentive and disincentive schemes for stimulating the small family norm and contraceptive use, and 6) strong commitments to the family planning program by political leaders. The new demographic targets during the Sixth Five-Year Economic and Social Development plan period(1987-91) have been set for a further reduction in the population growth rate to 1.0 percent by 1993, assuming that the TFR will decline to 1.75 level in 1995. This target is, however, not easy to achieve due to anticipated unfavorable factors like the strong boy preference, high discontinuation rates of reversible contraceptive methods, fertility termination-oriented contraceptive use, a plateau level of contraceptive practice rate that has mostly accounted for a sterilization, shortened length of birth intervals, and the changing patterns of contraceptive mix. The recent changes in contraceptive and fertility behaviors clearly indicate that the past quantity-oriented management system of the national program should be redirected toward a quality-oriented approach. Particularly, program efforts should be expanded to recruit new contraceptive users in the 20s of younger age groups, both for birth spacing and controlling their fertility since the women aged 20 to 29 account for more than 80 percent of the total annual births in recent years. In addition, the current contraceptive fee system of the national family planning program should be gradually shifted from free contraceptive services to a acceptor's charge system, and the provision of contraceptive services through the medical insurance system, which will cover the entire population by 1989, should be accelerated as a means of integration of family planning program with other health programs.

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