Java 병행프로그래밍 도구의 개발

박양수,김현규,문남두,이명준 울산대학교 1999 공학연구논문집 Vol.30 No.2

분산응용시스템은 서비스의 효율향상을 위해 일반적으로 병행성을 지원하는 것이 바람직하다. 그러나 병행성을 지원하기 위한 프로그래밍 기법은 난이도가 높은 구현 기법이며, 대부분의 프로그래밍 언어에서 이를 직접적으로 지원하지 않으므로, 분산응용시스템을 위한 개발자의 부담을 가중시키고 있다. 본 논문에서는 현재 분산응용시스템의 작성에 널리 쓰이고 있는 Java에서 병행성을 체계적으로 지원하기 위한 기반으로서, 세미포어나 조건변수와 같은 고수준 동기화 도구의 개발에 대해 소개하였다. 이러한 Java고수준 동기화 도구는 순수한 Java로 개발되어 이식성을 지니고 있으며, 개발자가 쉽게 기술할 수 있는 인터페이스를 제공하고 있다. 또한 Java가 지닌 대중성으로 인해 대부분의 분산응용시스템의 구축에 널리 사용될 수 있을 것으로 기대된다. In a development of distributed applications, it is desirable for a server to support concurrency in order to provide effective services. However, the programming mechanism for concurrency is difficult to implement correctly, so most programming languages do not support this facility directly. Therefore, the fact imposes extra burdens to the developers for distributed applications. The high-level synchronization tools such as Semaphores and Condition Variables in Java are suggested as a basis for systematically supporting concurrency control. The suggested high-level synchronization tools also have a good portability since it has developed in pure Java. In addition, due to the popularity of Java, these tools will ho a long way with developers in building distributed systems.

대학생의 성희롱·성폭력 실태에 관한 연구

박금주,김두화,김성현 濟州大學校 學生生活硏究所 2005 學生生活硏究 Vol.26 No.-

The purpose of this research is to understand the sex culture of college students by surveying the students' awareness and experience about sexual harassment and sexual assault, and their responses and opinions, and ultimately to provide basic data for in-campus programs and guidance against sexual harassment and assaults. To this end, the survey was composed of three parts; awareness on sexual harassment and sexual assaults, experience of sexual harassment or assault, and opinions on the consultation program on harassment and sexual assaults. The survey was conducted among 1,000 students in 9 colleges of Cheju National University (CNU), and analyzed the answers of 964 respondents. This research used SPSS statistical program to process data and conducted t-verification and F-verification. The results of the research are as follows. 1) The awareness on sexual harassment and assaults CNU students' common notions on sexual assaults, attitudes toward sexual relations, views on sexual harassment are a little different from the generally accepted ones, but lower than socially expected. In general, male students have more stereotypes on these matter sand take them less seriously than female students. Both of them have a man-oriented attitude. While female students take sexual harassment and sexual assaults as social problems, male students just take them as flirting. 2) Experience of sexual harassment and assaults After conducting a survey with three cases; committing experience, suffering experience, and experience of hearing of or seeing, there is no case in committing experience. In case of suffering sexual harassment or assaults, verbal, nonverbal, and physical cases are answered in order. In case of verbal harassment, female and male students suffer similarly, while more male students experience nonverbal, physical harassment and assaults, which shows that sexual harassment and assaults are happening irrespective sex. As to inflictors, strangers are the most. Sexual harassment and assaults occur more in other places rather than in campus, while in-campus cases are relatively less answered. In-campus cases are mostly between students, but there are cases where a staff member or a professor is an assailant, though very rare. About the reaction to sexual harassment and assaults, the highest number of students, male and female, answered they say "No" and ask to stop. Their reactions seem to be active and desirable. Most of them talk with their friends about the problem. 3) Opinion on the sexual harassment and assaults consultation center The level of awareness of CNU students about the center's regulations on sexual harassment and assaults cases is very low; therefore they said the center should give the priority to education for sexual assaults prevention. - As equally important as to resolve the cases of sexual harassment and assaults, there should be efforts to build a common perception on sexual harassment and assaults. To this end, education and discussion programs should be activated and continued to give students a right understanding of this issue. - In-campus sexual harassment and assaults are mostly between students, but there are cases where a staff member or a professor is an assailant, though very rare. Since such a case, if happening, is related to officials' duty and authority, it should be completely prevented. - Education program for the prevention of sexual harassment and assaults would be desirable to conduct in a small group consisting of friends or peers. - It is needed to widely inform members of the university about the regulations on sexual harassment and assaults. In this regard, compulsory and regular education should be offered to all the CNU students rather than one time campaign. - It would be desirable for the center to conduct all-year programs for the prevention of sexual harassment and assaults.

메타분석을 통한 가정특성 관련변인이 학업성취에 미치는 영향

박성열,구병두,임현걸 건국대학교 교육연구소 2000 論文集 Vol.24 No.-

This paper was designed to synthesize quantitatively the master's theses and doctoral dissertations focusing on effects of family background traits related variables on academic achievements in Korean. This task was accomplished by utilizing the meta-analysis technique of research integration as defined by Glass(1982). Basically, meta-analysis is a statistical analysis of the summary findings of many empirical studies. Its purpose is to draw reliable and general conclusions form a large and complex body of literature on a common topic. Thus, the primary purpose of this paper was to conduct a quantitative synthesis of 96 master's theses and doctoral dissertations focusing on the effects of academic achievements using family background traits as independent variable and academic achievement as dependent variable. Nine independent variable were chosen by means of in depth review of those previously mentioned 96 studies. The independent variables employed in this study include psychologcal environment, physical environment, family structure, public and private educational expenditures, education process, breeding and education method of parents, socio-economic status, parents' characteristics, and role expectation. These variable are cartegorized by two different groups according to the traits of factors in terms of family environment variable group and parent's characteristics variable group. This study set the following questions to be answered: (1) How large are the grand average effect size of variables of family background traits proposed in this study on student's academic achievement?; (2) How different the effect size of the two family background traits related variable groups, naimly family environment and parents characteristics variable group on student's academic achievement?; and, (3) How different the effect size of the nine family background traits related independent variables on student's academic achievement? In order to answer the research questions, the researcher followed the standard procedures as such locating published studies to collect primary data, analysing and cording the characteristics and outcomes of the studies, and carring out statistical procedures of mata-analysis to describe the overall and sub-variable effects. Primary source of data was decided to limit within the master's these and doctoral dissertations in order to achieve the reliability and validity of the study results. By using the CD-ROM titled 'masterㆍdoctoral dissertation index' published by National Central Library in 1995 and 1997, a total of 112 studies were located and collected. Out of 112 studies, 96 studies were selected by excluding those studies that are not possible to employ mata-analysis such as studies used qualitative research method. While classifying family background traits related variables some of studies were also excluded in this study due to failing a consensus among the five specialists participated in this process. The effect size were calculated by using two different approaches depending upon the applicability of effect size formula. One was by using mean and standard deviation of experimental group and their countpart. The other was using transformational formula suggested by Wolf(1986) for the studies that have not presented descriptive statistics. The result of this study may be summarized as follows: (1) The grand average degree of effects of the academic achievement factors proposed in this study turned out to be .33. This means that if the average size of effects of the academic achievement factors of the controlled group is 50 percentile in normal distribution, that of the experimental group becomes 62.93 percentile. As it were, the latter surpass the former by 12.94 percentile. (2) Between the two groups of academic achievement factors proposed in this study, in terms of family environment variable group and parent's characteristics variable group, the former factors showed the higher average effect size, its average effect size being .35. Considering the grand average degree of effects size of .33,it can be suggested that those family environment related variables effects more on the student's academic achievement compare to the variables of parents' characteristics. Among the nine family background traits related independent variables on academic achievements proposed in this study, the variable of educational process showed the highest average effect size of 1.40, as followed by socio-economic status(effect size of 0.55),role expectation(effect size of 0.48), and physical environment(effect size of 0.40). The effect size of these variables turned out to be bigger that the grand average effect size of .33. This result means that these variable effects on student's academic achievement a lot more compare to other variable proposes in this study. In fact, the effect size of those variable such as phychologcal environment(effect size of 0.27), breeding and educational method of parents(effect size of 0.27), family structure(effect size of 0.26), public and private educational expenditures(effect size of 0.26), and parents' characteristics(effect size of 0.14) turned out to be much smaller than that of previously mentioned variables. It means that the variable of psychologcal environment, breeding and education method of parents, family structure, public and private educational expenditures, and parents' characteristics effect less on student's academic achievement compare to the variables of educational process, socio-economic status, role expectation, and physical environment.

이중형질전환에 의한 웅성불임유기유전자의 발현억제

박영두,김현욱,박범석,진용문,정태영 慶熙大學校 1997 論文集 Vol.26 No.-

This study was carried out with the purpose of looking into the regulation of gene related to anther development, and applying their promoter to induce male sterile plants and restore their fertility. Progenies of transgenic male sterile tobacco plants containing anther specific promoter (BAN215) and diphteria toxin A (DTx-A) gene were analyzed by danamycin screening and pollen observation. DTx-A gene in male sterile plants was confirmed by PCR with the two synthetic primers, 5'-AACTTTTCTTCGTACCAC-3' and 5'-GCTTTCGCCTGTTCCCAG-3', from the sequence of DTx-A genes. The fragment of 350bp was appeared when the PCR product of 428 bp was digested with Rsal. pDTx-2 containing DTx-A gene was used as a control (DTx). Some of them were double transformed with the construct of BAN215 promoter and antisense DTxA (pKDA215b) to test restoration of fertility.

금속염 환원 세균의 생리 및 생태적특성 (총설)

박두현 서경대학교 1996 論文集 Vol.24 No.-

라벨링과 레벨세트 이론을 이용한 양방향 곡선 전개 형태 추출

박수형,하진일,주동현,염동훈,김두영 동아대학교 정보기술연구소 2002 情報技術硏究所論文誌 Vol.9 No.2

In this paper, We propose the method of initial curve creation in levelset evolution for the edge of objects or the shape extractions. The shape of traditional initial curve is including edge. But we improve the speed of processing to draw many initial curve using special parameter which was solved by binary processing and sequence labeling. In particular, it is necessary to efficiently reduce noise, we use anisotropic diffusion filter. This filter is to reduce blurring that is the fault of traditional filter processing and to preserver an accurate edge part. The levelset method using inward and outward evolution extracts the edge of object drawn initial curve, it performs to calculate shrinking and expanding at the same time.

Most Probable Number 방법을 이용하여 측정한 중랑천 河床土壤의 혐기성 세균의 수와 수질과의 상관 관계

박두현,김병홍,임시근,최영효 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.3

중랑천의 하상 토양의 혐기성 호흡세균의 분포를 MPN법으로 조사하였다. 철이온환원세균을 조사하기 위해 배양액 중의 Fe(Ⅱ)을 확인하는 변형된 oxalate-ferrozine 법을 개발하였으며, 황산염환원세균(SRB)과 메탄생산세균을 각각 FeS 침전과 head space의 CH_4를 검출하는 방법을 채택하여 중랑천 지천과 본천의 혐기성 미생물 분포를 조사한 결과 오염 정도가 상대적으로 높은 본천에서 철이온환원세균이 10^7~10^8 cells/g 정도로 조사되었으며 지천의 경우 10^7 cells/g이었다. 우이천 상류를 제외한 모든 조사 지점에서 SRB와 methanogen 이 10^3 cells/g이었다. 이 결과는 분류 하수관의 설치로 유기물의 유입이 낮아진 조건에서도 하상의 침전층에서 유래하는 유기물을 이용하여 철이온환원세균이 생장할 수 있으며, SRB와 methanogen의 생장은 철이온환원세균에 의해 방해를 받는다는 것을 나타낸다. Sediments collected from the Jungnang-cheon and its tributaries were used to enumerate anaerobic bacteria by most probable number (MPN) methods. A simple method was developed to detect ferrous ion in the culture fluid in order to count the number of iron ion reducers, and sulfate-reducing bacteria (SRB) and methanogens were detected by the presence of FeS precipitate in the culture or methane in the head space, respectively. The numbers of iron reducer was in the range of 10^7~10^8/g in the sediment of the stream containing higher organic content than the tributaries. The sediments of tributaries were analyzed to contain iron reducers less than 10^7 cells/g. With one exception the numbers of SRB and methanogens were less than 10^3 cells/g in the sediment. From these results it is concluded that organics in the sediment support the growth of iron reducers, which out-compete SRB and methanogens.

산업용 로울러기의 협착재해 감소방안

박재범,강동규,김두현 한국안전학회 2003 한국안전학회지 Vol.18 No.2

The roller machines installed in the industrial field are operated under hazardous conditions due to no safety devices available, human error during operation, defective safety devices, and inadequate regulation even in case that safety devices are provided. Up to now, most roller machines installed in domestic field are provides with band breaking system as a safety device. In this study, the emergency stop distance is measured within the limit of domestic regulation but violates a foreign regulation(EN1417). Consequently, it is concluded that the roller machines with a band breaking system have high possibility of death or serious injury of the operator and the system should be improved with the introduction of additional safety devices. This thesis suggests the safety measures suitable for the roller machines with different drive systems based on the experiment results. The use of the newly developed safety system has been tested in many cases.

분산 Model의 해석적 비교에 관한 연구

朴慶愛,鄭一鉉,姜斗煥 단국대학교 대학원 1984 學術論叢 Vol.8 No.-

Estimates of dispersion coefficients in flowing fluids may be made from measurements of the step response of this system and comparisons of the experimental output concentration with the concentration calculated from theoretical consideration. Comparisons of theoretical and experimental concentration in the time domain and in the Laplace transform domain are considered. When the outlet signal was calculated by the method of moments, an accurate value of the dispersion coefficient could not be found when dispersion was small because of the effect of errors in the tails of the response. It is found that good estimates of dispersion coefficients can be made from comparisons in the Laplace transform the appropriate ranges of transform parameters are chosen for the comparisons. The optimum weighting factors are defined as those which give the most reliable parameter estimated from the experimental data. The application of the weighted moments method of parameter estimation to typical models in R.T.D. work has been considered, and it has been found superior the to variance method. The relation of this method to other methods has been demonstrated, and a physical interpretation of the method, which provides insight into the optimum choice of the weighting factor, is given. This work took advantage of the step response method that was not affected by the fluid flow in the tracer injection method. So, we were looking for the character of the axial dispersion and the accurate axial dispersion coefficient D_L in fixed bed. The result showed that axial dispersion coefficient D_L was related liearly to superficial velocity and particle diameter, respectively. The equation for the axial dispersion coefficient in the liquid fixed bed is expressed as D_L=0.698U_5^0.532dp^0.643.

국민학교 컴퓨터 교육과정의 새 모델 제시에 관한 연구

박두순,배상현 순천향대학교 1992 논문집 Vol.15 No.3

A model for computer education within primary schools is proposed. This model asserts that primary school have a valuable computer education. Without any definite objective, contents, the current 5th curriculum of primary school has assigned to computer education only a 13-hour that it is absorbed as a part into the subject of Shil-Gwa of 4th, 5th, 6th grades. Therefore it is hard to expect now that teachers have a good computer education. This paper analyses current curriculums of computer education of primary schools and checks their problems. And so, I propose a new curriculum of computer education in primary schools.