• 공업화학
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• 제7권1호
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• pp.162-170
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• 1996

접촉분해경유(Light Cycle Oil : LCO)중에는 엔지니어링 플라스틱 및 고분자 액정 등의 기초 원료로서 각광 받고 있는 2,6-dimethylnaphthalene(2,6-DMNA)이 함유되어 있다. 본 연구는, LCO중에 함유된 2,6-DMNA의 분리, 정제를 위한 전처리조작으로서 LCO중에 함유된 dimethylnaphthalene(DMNA)이성체 혼합물의 농축을 추출-증류의 조합에 의해 실험적으로 검토했다. 또, LCO중에 함유된 DMNA이성체 혼합물의 농축에 대한 증류와 추출-증류의 조합을 비교, 검토하였다. Dimethylsulfoxide수용액을 용매로 사용한 회분병류 5회 평형추출로서 LCO중에 함유된 방향족 성분을 회수한 결과, 회수된 추출유중의 나프탈렌류 성분(탄소수 : 10-12)의 농도는 LCO중의 나프탈렌류 성분의 그것에 비해 높았으며, 나프탈렌류 성분의 수율은 탄소수가 작은 성분일수록 컸다. 5회 평형추출에 의한 DMNA이성체 혼합물의 회수율은 65wt%이었다. 추출유의 회분증류로서 얻어진 DMNA을 함유한 유출액을 재차 회분증류함으로서 60wt%의 고농도 DMNA이성체 혼합물을 함유한 유출액의 회수가 가능했다. LCO중에 함유된 DMNA이성체 혼합물의 농축에는 LCO의 직접증류보다 추출-증류의 조합이 더 효과적이었다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권3호
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• pp.1209-1214
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• 2016

Background: Cigarette smoking constitutes a major threat to the health and wellbeing of teenagers. While smoking has been on decline in the developed countries, the reverse is the case in developing countries. The aim of this study was to determine the age of initiation, determinants and prevalence of cigarette smoking among teenagers in Mushin Local Government Area of Lagos state, Nigeria. Materials and Methods: This was a descriptive cross-sectional study among 475 teenagers selected by multistage sampling. A pre-tested, structured, interviewer-administered questionnaire was used for data collection. The study was carried out in November, 2014. Results: Response rate was 84.6%. Mean age of the respondents was $16.4{\pm}1.65years$. Range and mean age of initiation of cigarette smoking were 7 to 17 years and $12.0{\pm}3.32years$ respectively. Teenagers who were above 15 years (OR:5.13, 95%CI: 0.87-30.26), males (OR:5.19, 95%CI: 1.57-17.18), married (OR:8.41, 95%CI: 1.04-63.35), had ${\leq}$primary school education(OR:4.31, 95%CI: 1.07-17.33), influenced by friends(OR:308.84, 95%CI:84.87-1123.81), and influenced by advertisements (OR:27.83, 95%CI: 3.92-197.64) were more likely to have initiated cigarette smoking. Furthermore, teenagers who were males (OR:12.77, 95%CI: 2.90-56.28), married (OR:19.24, 95%CI: 2.05-180.45), had ${\leq}$primary school education(OR:7.85, 95%CI: 2.37-26.01), influenced by friends(OR:28.56, 95%CI: 10.86-75.07), and influenced by advertisements (OR:5.95, 95%CI: 1.72-20.61) were more likely to be current cigarette smokers. In addition, 24.9% had initiated cigarette smoking while 14.7% were current smokers of cigarette. Conclusions: Mean age of initiation of cigarette smoking was $12.0{\pm}3.32years$. Determinants of cigarette smoking were age, gender, marital status, educational background, friends and advertisements. Life time prevalence of cigarette smoking was higher than prevalence of current cigarette smokers. Cigarette smoking reduction programs should take these factors into consideration.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2991-2999
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• 2013

Background: Introduction of the HPV vaccine is a forefront primary prevention method in reducing the incidence of carcinogenic human papillomavirus (HPV) and cervical cancer. The Malaysia government has implemented the National HPV immunisation programme since 2010, supplying HPV vaccine free to targeted 13 year olds. This study aimed to explore the level of knowledge among mothers on cervical cancer, HPV, HPV vaccine and National HPV (NHPV) immunisation programme since its' implementation. It also assessed acceptance of mothers towards HPV vaccine being administered to their daughter, son or themselves. Materials and Methods: A cross sectional study was conducted on 155 respondents using self-administered questionnaires; conducted in December 2012 at the Obstetrics and Gynaecology Clinic in a teaching hospital in Kuala Lumpur. Respondents were selected using a multistage sampling technique. Results: A response rate of 100% was obtained. Overall, 51.0% of mothers had good knowledge, with 55% having good knowledge of cervical cancer, 54.2% for both HPV and the National HPV immunisation programme and 51.0% for the HPV vaccine. Regression analyses showed that ethnicity was associated with knowledge on cervical cancer (p=0.003) while education was associated with knowledge on HPV (p=0.049). Three factors are associated with knowledge of the National HPV immunisation programme; ethnicity (p=0.017), mothers' education (p=0.0005) and number of children (p=0.020). The acceptance of HPV vaccine to be administered among daughter was the highest at 87.1%, followed by for mothers themselves at 73.5%, and the least is for sons 62.6%. Conclusions: This study found that the overall level of knowledge was moderate. Adequate information on cervical cancer, HPV, HPV vaccination and the National HPV immunisation programme should be provided to mothers in order to increase acceptance of the HPV vaccine which can reduce the disease burden in the future.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.407-408
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• 2011

Natural boron consists of two stable isotopes 10B and 11B with natural abundance of 18.8 atom percent of 10B and 81.2 atom percent of 11B. The thermal neutron absorption cross-section for 10B and 11B are 3837 barn and 0.005 barn respectively. 10B enriched specific compounds are used for control rods and as a reactor coolant additives. In this work 2 methods for boron enrichment were analysed: 1) Gas irradiation in static conditions. Dissociation occurs due to multiphoton absorption by specific isotopes in appropriately tuned laser field. IR shifted laser pulses are usually used in combination with increasing the laser intensity also improves selectivity up to some degree. In order to prevent recombination of dissociated molecules BCl3 is mixed with H2S 2) SILARC method. Advantages of this method: a) Gas cooling is helpful to split and shrink boron isotopes absorption bands. In order to achieve better selectivity BCl3 gas has to be substantially rarefied (~0.01%-5%) in mixture with carrier gas. b) Laser intensity is lower than in the first method. Some preliminary calculations of dissociation and recombination with carrier gas molecules energetics for both methods will be demonstrated Boron separation in SILARC method can be represented as multistage process: 1) Mixture of BCl3 with carrier gas is putted in reservoir 2) Gas overcooling due to expansion through Laval nozzle 3) IR multiphoton absorption by gas irradiated by specifically tuned laser field with subsequent gradual gas condensation in outlet chamber It is planned to develop software which includes these stages. This software will rely on the following available software based on quantum molecular dynamics in external quantized field: 1) WavePacket: Each particle is treated semiclassicaly based on Wigner transform method 2) Turbomole: It is based on local density methods like density of functional methods (DFT) and its improvement- coupled clusters approach (CC) to take into account quantum correlation. These models will be used to extract information concerning kinetic coefficients, and their dependence on applied external field. Information on radiative corrections to equation of state induced by laser field which take into account possible phase transition (or crossover?) can be also revealed. This mixed phase equation of state with quantum corrections will be further used in hydrodynamical simulations. Moreover results of these hydrodynamical simulations can be compared with results of CFD calculations. The first reasonable question to ask before starting the CFD simulations is whether turbulent effects are significant or not, and how to model turbulence? The questions of laser beam parameters and outlet chamber geometry which are most optimal to make all gas volume irradiated is also discussed. Relationship between enrichment factor and stagnation pressure and temperature based on experimental data is also reported.

• 보건행정학회지
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• 제18권3호
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• pp.18-40
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• 2008

Measurements of health related quality of life can be used to compare patients with specific conditions to average individuals in the general population in a similar age and gender group. However there are few data available regarding health related quality of life for the general population of Korea. Therefore, this study was conducted to examine the validity of the Korean version of EQ-5D and to measure the health related quality of life of the general adult population in a metropolitan city. The survey was cross-sectional and employed a stratified and multistage sampling design through 100 examination sites in 5 districts of UIsan. A total of 12,644 individuals from 4,112 households participated in the survey. Of these, we analyzed data from 8,068 adults who were over 19 years old and completed the EQ-5D. To examine the validity of the questionnaire, the differences in 5 dimensions and the $EQ-5D_{index}$ were analyzed with regard to demographic and socioeconomic factors such as sex, age, income, and education. In addition, visual analogue scales (VAS) were used to evaluate the overall health related quality of life issues of the respondents. The level of health related quality of life of the general adult population was then compared with the results from the third Korean National Health and Nutrition Examination Survey and other countries. There were a small number of people with problems related tomobility, self-care, and usual activity. In addition, many people complained ofpain/discomfort and anxiety/depression. The complaint rate in each dimension, VAS, and $EQ-5D_{index}$ indicated relatively better states for males, the younger group, the higher income group, and the higher education group. In addition, the level of health related quality of life of the general population of Ulsan was relatively higher than that of Koreans nationwide as well as the populations of other countries. EQ-SD provided a valid measure of the health-related quality of life of the general adult population. In addition, the results of a survey of Ulsan revealed that the quality of life of its population is better than that of the overall population of Korea and of the populations of other countries.

• 한국정보과학회논문지:정보통신
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• 제29권6호
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• pp.696-705
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• 2002

본 논문은 멀티캐스트 ATM 스위치를 위한 새로운 복사망에 관하여 언급한다. Lee의 복사망 제안 이후 현재까지 많은 연구가 진행되어 왔으나 스위치 내에서의 오버플로우와 셀 충돌 문제는 여전히 문제점으로 제기되어 왔다. 본 논문에서는 치러한 문제점을 개선하기 위해 공유 버퍼를 갖는 3차원 멀티캐스트 스위치 구조를 제안함으로서 높은 부하에서도 다중경로와 다중출력을 통해 오버플로우와 충돌을 줄일 수 있는 방법에 관하여 언급한다. 이를 위해 큰 팬아웃의 셀을 처리하기 위한 셀 분할 알고리즘(Cell splitting algorithm)과 Lee의 Broadcast Banyan Network을 확장시킨 복사망을 재안하였다. 셀 복사는 셀의 두 비트 멀티캐스트 패턴과 부울 방식의 내부분할 알고리즘(Boolean interval splitting algorithm)을 사용하여 네트워크가 갖는 자가-라우팅의 특성에 따라 이루어지도록 하였다. 제안된 복사망에서는 Lee의 복사망에서 문제가 되었던 오버플로우 문제, 큰 팬아웃의 셀 처리 문제, 셀 충돌 문제 등을 개선시킴으로서 기존의 멀티캐스트 ATM 스위치 성능을 향상시키고자 하였다. 시뮬래이션에 의한 성능 평가 결과 기존의 방법과 비교하여 산출량, 셀 손실률, 셀 지연에 대해 좋은 성능을 보이고 있다.

• Journal of Preventive Medicine and Public Health
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• 제53권2호
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• pp.89-97
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• 2020

Objectives: The quality of life (QoL) of the elderly and elder abuse are growing public health concerns. This study aimed to evaluate the prevalence of abuse and the association between QoL and abuse in older adults. Methods: Multistage random cluster sampling, along with valid QoL (LEIPAD: LEIden, the Netherlands; PADua, Italy; Helsinki, Finland) and abuse questionnaires, were used to assess QoL and elder abuse. Path analysis was performed using Mplus. SPSS and AMOS were used for the other analyses. Results: A total of 386 elderly individuals with a mean age of 68.00±6.10 years were interviewed, of whom 200 (51.8%), 289 (74.9%), and 376 (97.4%) were women, educated, and married, respectively. Moreover, 167 (43.2%) had low-to-moderate QoL, and 108 (27.9%) had experienced a moderate level of abuse. QoL and abuse were inversely associated (r=-0.253), with men (β=-0.24) more affected than women (β=-0.21). Musculoskeletal disorders were also strong determinants of QoL in the elderly. QoL was strongly associated with emotional abuse, while abuse was highly related to the social component of QoL. Furthermore, emotional abuse was the type of abuse most significantly associated with the self-care, depression/anxiety, cognitive, and social components of QoL. Sexual abuse, violation of personal rights, and neglect were the main determinants of the physical functioning, life satisfaction, and sexual domains of QoL, respectively. Conclusions: Nearly half of the elderly individuals lacked a high QoL, and at least one-fourth had experienced some form of abuse. Elder abuse was correlated inversely with QoL. Therefore, preventive interventions are recommended to decrease elder abuse in the family, community, and other settings.

• 대한지역사회영양학회지
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• 제16권6호
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• pp.740-750
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• 2011

With a recent increase in dietary supplements (DS) consumption among children in Korea, this study was performed to examine the influencing factors on children's DS consumption. A nationwide survey was conducted employing 3 representative samples of children for summer & fall of 2008 and spring of 2009 by stratified multistage sampling of 120 survey sites per season based on the 2005 census population. Approximately 30 households from each survey site were screened for residing children of 0-19 years and about 1,700 households remained as eligible samples per season. Trained dietitians visited households to perform face-to-face interview to children and/or parents regarding DS consumption including health functional foods (HFF), vitamins/minerals (V/M) supplements and other food supplements during 1 month prior to interview. Out of 5,328 children responded, 18.7% reported DS consumption. Consumption rate was higher in boys (19.9% vs. 17.3% in girls, P < 0.05) and youngsters (22.8% compared to 15.0% in adolescents, P < 0.001). Children from higher income family (P < 0.001), those living in apartments (P < 0.001), those residing in metropolitan area (P < 0.001), and those of mothers with higher education (P < 0.001) were more likely to take DS. Also, mother's employment status and occupation were significantly associated with children's DS consumption. The most popular DS was HFF (72.1%), which was consumed more in children of higher income family. It is revealed that socioeconomic factors affect children's DS consumption significantly. Also it is necessary to estimate children's V/M intake from DS and foods together especially because there are tolerable upper limits set for V/M for safety purposes.

• International Journal of Knowledge Content Development & Technology
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• 제10권3호
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• pp.33-50
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• 2020

Knowledge recipes are packages of knowledge which arise from the process of combining the knowledge assets in the organization in distinctive ways. This involves converting them into useful outputs which are the ideal core competitive advantage enablers for companies. The major objective of this study was to propose a knowledge recipe for financial-sector state corporations in Kenya. The study adopted a convergent parallel mixed methods research design. Quantitative and qualitative data were collected using questionnaires and key informant interviews. The target population of the study was 1574 respondents drawn from all financial state corporations. A multistage sampling technique was used for the study. The first phase involved purposive sampling of the organizations to be studied whereby the four state corporations namely: Capital Markets Authority, Competition Authority of Kenya, Kenya Investment Authority, and Kenya Revenue Authority were identified. The second phase entailed stratified sampling of the respondents in three strata namely senior management team, knowledge management team, and general staff. The authors used a census of all senior management team and knowledge management staff while a simple random sampling technique was used for the general staff. By use of the Krejcie and Morgan table, the actual sample size was 358 respondents from all the four organizations. Data were collected using questionnaires and interview schedules. The qualitative data were analyzed using content analysis while the quantitative data were analyzed by the use of Ms. Excel and VOSviewer and presented using pie charts, bar graphs, and tables. The response rate for this study was 257 (72%). The study revealed that while most employees in the financial sector organizations understand their knowledge needs, knowledge types, knowledge uses and knowledge gaps, they do not have a universal knowledge recipe to facilitate effective knowledge management in their organizations. Consequently, the authors propose a universal knowledge recipe for the state corporations in the financial sector in Kenya. The ingredients of the recipe are legal-knowledge (18%), financial knowledge (15%), administrative knowledge (11%), best practice (10%), lessons learnt (8%), human resource knowledge (8%), research and statistics knowledge (7%), product knowledge (6%), policy and procedure knowledge (5%), ICT knowledge (4%), investor knowledge (3%), markets knowledge (2%), general knowledge (2%) and regulatory framework knowledge (1%).

• 정보보호학회논문지
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• 제29권6호
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• pp.1243-1257
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• 2019

IoT 환경이 등장함에 따라 여러 스마트기기를 통해 소비자에게 편리함과 다양한 서비스를 제공하고 있다. 하지만 개인 정보 유출과 같은 보안 위협 사례가 보고되면서 IoT 환경상의 보안 문제의 중요성이 대두되고 있고 특히 키 관리의 안전성 문제에 대해서 거론되면서 PUF를 활용한 방안이 대응 방안으로 거론되고 있다. 키 관리 문제와 관련하여 그룹 키 관리 시스템의 안전성 문제에 대해서 MIPUF를 이용한 키 관리 프로토콜이 제안된 바가 있다. 해당 시스템은 경량 IoT 환경에 적용할 수 있고 PUF의 안전성으로 인해 전체 시스템의 안전성을 보장하지만, 일부 과정에서 안전성 및 연산의 효율성 측면에서 한계점을 보인다. 본 논문은 구성원에 대한 인증 추가, 데이터 간의 독립성 보장, 불필요한 연산을 축약, 그리고 데이터베이스 검색의 효율 증대함으로써 기존 프로토콜을 개선한다. 특정 공격에 대해 안전성 분석을 진행하고 연산량 비교를 통한 효율성 분석 결과를 제시한다. 이를 통해 본 논문은 데이터에 대한 신뢰도를 향상하고 본 논문이 제안한 방안이 기존 프로토콜보다 더 경량화 시켰음을 보인다.