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

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• v.2
• /
• pp.451-454
• /
• 2006

본 논문에서는 헬기의 인공 시계 시스템용 DGPS/INS 통합 항법 플랫폼을 설계하였다. DGPS/INS 통합 항법 플랫폼 하드웨어는 PowerPC CPU와 Flash ROM과 DDR SDRAM를 이용하여 설계하였다. DGPS 수신기와 IMU와의 연결을 위한 외부 인터페이스부는 직렬 통신을 사용하는 DGPS수신기와 IMU는 모두 사용할 수 있도록 하기 위하여 직렬 통신 방식인 UART 컨트롤러와 SDLC 컨트롤러를 사용하여 설계하였다. 실시간 운영체제를 기반으로 하는 플랫폼의 소프트웨어는 초기 정렬, 자세 계산, 속도 계산, 위치 계산, 통합 필터, 명령 처리 각각에 대하여 태스크로 구성하고 세마포어를 이용하여 태스크간의 동기가 이루어지도록 설계하였다. 통합 항법 플랫폼의 성능 평가를 위하여 차량 실험을 수행하였으며 상용 항법 시스템의 결과와 비교를 하였다.

• 한국환경농학회:학술대회논문집
• /
• 2011.07a
• /
• pp.292-292
• /
• 2011

• Applied Chemistry for Engineering
• /
• v.7 no.4
• /
• pp.679-690
• /
• 1996

Acrylic copolymer was synthesized from 2-dimethylaminoethyl methacrylate and alkylmethacrylate containing long chain hydrocarbon group. To facilitate emulsification in water, acrylic copolymer was treated with acetic acid, and therefore acetated acrylic copolymer was produced. Acetated acrylic copolymer was perfectly emulsified in water and showed increased emulsion stability. Polymer as a cement dispersion agent(PDCM-PSD) was prepared by blending the newly synthesized acetates acrylic copolymer with sodium gluconate, oleic acid, and triethanolamine. The applicability of the blended polymer was examined, and it was found that the effects of dispersion and water-proof(0.3~0.5) were excellent.

• Journal of agricultural medicine and community health
• /
• v.32 no.2
• /
• pp.63-73
• /
• 2007

Objectives: The purpose of this study was to obtain basal information to establish a proper birth-encouraging policy in the future through the survey of the attitude towards childbirth and its related factors among female students in junior, senior high school, and university. Methods: A survey was performed for 2 weeks in June, 2006, for a total of 688 female students which included 185 ones in a girls' junior high school and 242 ones in a girls' senior high school in Sacheon, and 261 ones in two universities in Jinju. The selfadministered questionnaires developed by the authors included the socio-demographic characteristics, the attitude towards childbirth, the preference of a son for their future child, the belief on relative importance of family or work after marriage, the seriousness perception of low birth rate in Korea, frequencies of education in school about low birth rate. The attitude was measured by an answer to the question of 'To what degree do you think you are going to have a child(or children)?' Results: The proportion of positive attitude towards their future childbirth was 76.2% in junior high school, 63.9% in high school, and 82.8% in university students (p<0.01). In the logistic regression analysis, the significant factors related with positive attitude towards future childbirth were school grade, preference of a son for their future children, and belief on relative importance of family or work after marriage. Conclusions: It suggests that the related factors with positive attitude towards future childbirth need to be considered to make a proper birth policy.

• Journal of Preventive Medicine and Public Health
• /
• v.43 no.1
• /
• pp.62-72
• /
• 2010

Objectives: To identify factors associated with cancer screening intention using the Theory of Planned Behavior (TPB). Methods: Among 55,920 eligible persons for National Cancer Screening Program (NCSP) in J city, 1,100 individuals were contacted. Of these, 797 were interviewed using a structured questionnaire. Thirty-six responses were excluded due to incomplete data. The remaining 761 completed questionnaires were analyzed to find factors associated with cancer screening intention. Results: Cancer screening intention was significantly associated with behavioral attitude (p<0.01) and subjective norm (p<0.01), but not with perceived behavioral control (p=0.29) in the TPB model. These three constructs explained 29.7% of cancer screening intention in multiple linear regression analysis. External factors such as socio-demographic status, health and health behavior variables explained 8.9% of screening intention. Among them, household monthly income, past cancer screening experience, exercise and daily eating habit were significantly associated with screening intention. Conclusions: Cancer screening intention may be influenced by focusing attitude, subjective norm in TPB model and other external factors. However, further studies are warranted to identify factors influencing cancer screening intention and behavior.

• Communications of Mathematical Education
• /
• v.25 no.1
• /
• pp.1-19
• /
• 2011

HPM(History and Pedagogy of Mathematics) become an important issue to us now. Study on old Korean mathematics books were made recently. We study mathematics books in Kyujanggak in this article. Horng Wann-Sheng 洪萬生, an math. historian and a member of editorial board of Historia Mathematica, visited Kyujanggak, the royal library of Joseon Dynasty. After his visit, he published a paper, "The first visit to mathematics books in Kyujanggak 奎章閣收藏算書初訪"(2008 Kyujanggak 32, p. 283-293). In his paper, he also raised several research problems on the history of Korean mathematics. In this paper, we analyze his paper "The first visit to mathematics books in Kyujanggak" and give some answers to those raised problems on Korean mathematics. Also we correct some misunderstanding of Horng on some facts. Especially, we make it clear that the author of SinJungSanSul(New Arithmetics 新訂算術) was not Lee Sang-Seol(李相卨), whom Horng considered as the author, but Lee Gyo-Seung(李敎承) through the correct translation of its preface and an article about its copyright lawsuit. And we added some pathways how Chinese mathematics books were imported by Joseon. We introduce the case of Hong Dae-Yong(洪大容) in detail.

• Environmental Analysis Health and Toxicology
• /
• v.9 no.1_2
• /
• pp.37-51
• /
• 1994

To evaluate the genotoxicities of workers exposed to glue and glue cleaning solution, ambient air monitoring of working place, animal study and human monitoring were carried out. By GC-MS analysis, air samples collected from shoesmaking plant were found to be toluene, xylene, cyclohexane, n-hexane, methyl ethyl ketone, trichloroethylene, butylacetate, isopropyl alcohol. Glue and glue cleaning solution from shoesmaking plant were applicated topically to the CD-1 mice. DNA was isolated from skin 24 hr following the application and analysed for DNA-adducts using the nuclease $P_1$version of $^{32}$P-postlabelling assay. RAL (Relative Adduct Labelling, adducts$10^8$ nucleotides) was significantly increased in a dose-dependent manner in the glue cleaning solution treated mice skin. Peripheral blood DNA-adducts of workers exposed to glue and glue cleaning solution were also analysed by the same method, but there were not significant differences in the peripheral blood DNA-adducts level between exposed and control workers. In addition, glue cleaning solution from shoes factory was evaluated for mutagenicity in the Salmonella plate incorporation assay using strains TA 100 and TA 1535 in the presence and absence of Arochlor 1254-induced rat liver S$_{9}$. There was evident mutagenicity for cleaning solution in TA 100 regardless of $S_9$, but TA 1535 showed positive only in the absence of $S_9$when predicted by Stead model of mutagenicity prediction (p=0.0000). The urine concentrates from workers and controls were also assayed for mutagenicity towards strain TA 100 of Salmonella typhimurium in the presence of $S_9$ using Kado's microsuspension assay, but their mutagenic activities were not found to be significant. These data suggest that shoesmaking workers are exposed to genotoxic compounds and need to be monitored by testing the mutagenicity of human urines. However, $^{32}$P-postlabelling application requires further validation for the routine monitoring of human exposure.osure.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.19 no.3
• /
• pp.250-260
• /
• 2009

To improve work environment for health managers, it was investigated about effect of job stress, psychosocial stress and job satisfaction of health managers on job commitment. The sample used in this study consisted of 166 persons of industrial health managers. The data were collected with self-administered questionnaires between November 2007 and January 2008, and the results analyzed with ANOVA and multiple regression analysis. Job stress was evaluated by using a Korean Occupational Stress Scale(KOSS), and Psychosocial wellbeing index-Short Form(PWI-SF) was used for a psychosocial stress level evaluation. Organized commitment evaluated loyalty, compensation, welfare, job immersion, external employment opportunity, total agreement with employer and personal ability development. In path analyses, interpersonal conflict, lack of reward, psychosocial distress were associated with job satisfaction. And psychosocial distress, job demand, job insecurity, organizational system, occupational climate were associated with organizational commitment. In considering above findings, the health program for psychosocial distress, improvement of job demand, job insecurity, organizational system, occupational climate would be implemented to increase organizational commitment of Health manager.

• Journal of KIISE
• /
• v.42 no.1
• /
• pp.107-113
• /
• 2015

In a database system, updates on pages that are made by a transaction should be stored in a secondary storage before the commit is complete. Generic secondary storages have volatile DRAM caches to hide long latency for non-volatile media. However, as logs that are only written to the volatile DRAM cache don't ensure durability, logging latency cannot be hidden. Recently, a flash SSD with capacitor-backed DRAM cache was developed to overcome the shortcoming. Storage devices, like those with a non-volatile cache, will increase transaction throughput because transactions can commit as soon as the logs reach the cache. In this paper, we analyzed performance in terms of transaction throughput when the SSD with capacitor-backed DRAM cache was used as log storage. The transaction throughput can be improved over three times, by committing right after storing the logs to the DRAM cache, rather than to a secondary storage device. Also, we showed that it could acquire over 73% of the ideal logging performance with proper tuning.