반도체의 광학적 성질에 관한 다체효과

홍성락 제주대학교 1982 논문집 Vol.14 No.-

We discuss the influence of finite electron densities and electron-electron interactions on optical properties of N type doped semiconductors.

Mossbauer 분광법과 X-선 회절법을 이용한 제주도 화산암의 연구

홍성락 제주대학교 사범대학 2001 백록논총 Vol.3 No.2

제주도 용암의 물리적 특성

홍성락 濟州大學校 基礎科學硏究所 2001 基礎科學硏究 Vol.14 No.2

제주도의 특정 4개지역을 선정하여 지역별로 화산암과 송이시료를 채취하여, 상온에서 이 시료에 대한 Mo¨ssbauer spectroscopy와 XRD를 이용한 실험결과를 보고한다. 시료에 대한 XRD실험에서 화산암에는 quartz, olivine, pyroxene, ilmenite, 송이에는 이 광물외에 hematite, magnetite등의 광물이 존재하고 있음을 확인하였다. 시료의 Mo¨ssbauer 스펙트럼으로부터 화산암은 olivine, pyroxene, ilmenite에 의한 세쌍의 quadrupole splitting을, 송이는 이 광물 외에 hematite, magnetite에 의한 두 쌍의 sextets을 얻었으며 화산암에 함유된 Fe는 약간의 Fe^(+3)를 제외하고는 거의 Fe^(+2)이고, 송이에 함유된 Fe는 약간의 Fe^(+2)를 제외하고는 거의 모두 Fe^(+3) 상태임을 확인하였다. We report the result of measurements using the Mossbauer spectroscopy and x-ray diffractometry(XRD) of samples of volcanic rock and scoria at room temperature which are distributed throughout four different sites on Jeju island. In the XRD results for these samples, we find that volcanic rock has minerals of quarts, olivine, pyroxene and ilmenite. Scoria has not only the aforementioned minerals but also hematite and magnetite. The Mossbauer spectra for Volcanic rock consists of three well defined quadrupole doublets of olivine, pyroxene and ilmenite with a dominant 2^(+) charge state and a small percentage of 3^(+) charge state of iron. On the other hand in Mossbauer spectra for scoria, we find that scoria has not only two well defined quadruple doublets of olivine and pyroxene but also two sextets of hematite and magnetite with a dominant 3^(+) charge state and a small percentage of 2^(+) charge state of iron.

화산암의 Mossbauer 분석

홍성락 제주대학교 1986 논문집 Vol.23 No.-

We report on the measurement of the iron-57 Mossbauer spectra for volcanic rock taken from Cheju island. M. W. Lee/l/has extensively studied the composition of lava samples from Cheju island based on chemical analysis. We find that the volcanic rock of Cheju island is composed of four principal minerals. The quadrupole doublets observed and the temperature dependence of the recoilless fraction. taken between 77 to 297K. are used as signatures of the chemical form. and we report the variations in the geochemistry for samples taken from different portions of the island.

CdS 박막의 열처리효과에 관한 연구

홍성락,최치규,현동걸 제주대학교 1984 논문집 Vol.17 No.-

The annealing effects of CdS thin films prepared by the chemical vapor deposition method have been investigated. At 380℃, the annealing of CdS thin films for 30 minutes in H_(2) gas and vacuum (10^(-5) torr) has led to enhance the electrical conductivity and crystal structure of them. The resistivities are increased by as much as two and concentrations of the CdS thin films annealed have very fluctuating values, this may be expected to attniute to the surface scattering and surface potential resulted from the defects.

보안이 강화된 특수목적용 웹서버 설계 및 구축 제안

홍성락,조인준 한국콘텐츠학회 2022 한국콘텐츠학회논문지 Vol.22 No.2

현재 웹 서버의 보안을 위해 관제와 모의 해킹을 한다고 해도 계속해서 취약점이 발생하고 해킹을 당하는 것이 현실이다. 해당 문제를 해결하기 위해 L4와 L5 사이에서 소켓을 사용해 모든 웹 통신을 제어할 수 있는 보안 웹 서버를 개발했다. 그리고 HTTP 응답을 줄 때 매번 파일과 헤더를 합치는 행위를 미리 합쳐놓는 방식을 제안했다. 그 결과 보안과 속도를 둘 다 향상할 수 있었다. 따라서 본 논문에서는 관제와 모의 해킹을 해도 취약점이 발생하는 이유와 그것에 대한 해결방안과 더 나아가 DB까지 보안을 유지할 수 있는 보안 웹 서버 개발 방식을 제안하였다. Currently, even if control and mock hacking are performed for the security of web servers, vulnerabilities continue to occur and be hacked. To solve this problem, we have developed a secure web server that can control all web communication using sockets between L4 and L5. And when giving HTTP responses, we proposed a method of combining files and headers in advance. As a result, both security and speed could be improved. Therefore, in this paper, we proposed the reason why vulnerabilities occur even if control and mock hacking occur, a solution to it, and a security web server development method that can maintain security up to DB.

C.V.D. 방법으로 제작한 CdS 박막의 성질에 관한 연구

홍성락 제주대학교 1984 논문집 Vol.17 No.-

CdS this films have been prepared by the chemical vapor deposition method, where the ultrasonic stirrer has been used as an evaporator of the mixed solution of cadium chloride and thiourea, and their electrical properties and crystal structures associated with the growth conditions have been investigated. This investigation shows that the electrical properties and crystal structures of CdS thin Films can be stron-gly influenced by substrate temperature, concentrations of mixed solution, evaporating rate and cooling rate. About 350℃ ,the exedmt CdS thin films arc obtained, the results were p^(12)~10^(a)cm, u=10㎠/v sec n=~10^(14)cm^(-13) and hexagonal structures with the principal orientation (002).

새로운 중합체 용액에서 Laser 광산란 실험

홍성락,김두철 제주대학교 1986 논문집 Vol.23 No.-

A measurements of reduced viscosity and light scattering study on new polyamides solution containing crown ether moieties were made in the presence of a salt(K^(+).Cs^(+). Rb^(+)). The result was that the reduced viscosity of solution increased rapidly as the concentration of solution decreased even if it was different as a sort of salt. In study of light scattering experiment. the angular dependent intensities of scattered light from each solution were measured. The Rayleigh ratios calculated from these data suggested that a change in molecular shape from coil to rod was responsible for the increasein the reduced viscosity of the polymar solution with dilution The reduced visosity calculated from light scattering data agreed well with those measured with a viscometer.

제주도의 신석기 시대 토기에 관한 Mossbauer 연구

홍성락,고정대,강동우 濟州大學校 基礎科學硏究所 1995 基礎科學硏究 Vol.8 No.1

The constitutional component, firing temperature and firing atmosphere of plain coarse pottery sherds unearthed from the remains of the Bawignul site of Bukchon in Cheju lsland at a neolithic era were studied by X-ray diffraction(XRD), thermomechanical analysis and Mossbauer spectroscopy. By the analysis of X-ray diffraction, the clay minerals of the plain coarse pottery sherds of the neolithic era contained no peaks by resoulution, but did contain those of quartz and plagioclase. By thermomechanical analysis, the transition of quartz of plain coarse pottery sherds appeared at about 600℃ and heat constraction of plain coarse pottery sherds clearly at about 820℃. The refiring of plain coarse pottery sherds of the neolithic era results in the four characteristic temperature ranges from the change of quadrupole splitting by Mossbauer spectrum at room temperature. It is estimated from 800℃ to 900℃ that original firing temperatures of plain coarse pottery sherds of the neolithic era at Bukchon through the change of Mossbauer parameters, X-ray diffraction analysis and thermomechanical analysis.

Mossbauer 분광학과 이성질체이동, 공명흡수 면적을 이용한 Debye 온도결정

洪性樂 濟州大學校 基礎科學硏究所 1988 基礎科學硏究 Vol.1 No.1

In this study, we have improved the methods determining the Debye temperature. From a fact that the kinetic temperature proposed by Mazo and Kirwood simplize the Mossbauer data we could compute the ?? using isomer shift variance about low temperature range, 50∼300K, and linearizing temperature To of data. Futhermore, we have tried automatic iteration process of log resonance absorption area ratios about ?? to determine the Debye temperature accurately. From each methods, we knew the ?? of iron foil stands on 476∼485 K. The credible ?? from Mossbauer data can be determined by the careful measurement and fine computer technique.