• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.162-170
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• 1996

Light cycle Oil(LCO) contains 2,6-dimethylnaphthalene (2,6-DMNA) which is used as the basic material for high performance engineering plastics and liquid crystal polymer. This study was experimentally investigated to concentrate a mixture of dimethylnaphthalene(DMNA) isomers in the LCO by extraction-distillation combination as a pretreatment for separation and purification of 2,6-DMNA in the LCO. Furthermore, concentration of a mixture of DMNA isomers in the LCO compared between distillation and extraction-distillation combination. The recovery of aromatics in the LCO was performed by batch cocurrent multistage extraction with dimethylsulfoxide and water mixture as solvent. The concentration of naphthalene group(carbon number 10-12) in the extracted mixture is higher than that in the LCO. The yield for naphthalene group increased with decreasing carbon number. The yield for a mixture of DMNA isomers obtained in 5 equilibrium extration runs was about 65%. the separation of individual components with extractedmixture was tested by batch distillation. Futhermore, for recovery of a mixture of DMNA isomers of high concentration, distillate containing DMNA was distilled. As a result, a mixture of DMNA isomers with high concentration such as 60wt% was recovered. The extraction-distillation combination was more effective than the distillation to concentration a mixture of DMNA isomer in the LCO.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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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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• v.14 no.5
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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.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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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.

• Health Policy and Management
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• v.18 no.3
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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.

• Journal of KIISE:Information Networking
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• v.29 no.6
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• pp.696-705
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• 2002

This paper presents a new copy network for multicast ATM switches. Many studies have been carried out up to date since the proposition of Lee's copy network. However, the overflows and cell conflicts within the switch have still been raised a problem in argument. In order to reduce those problems, we proposed a 3-dimensional multicast switching architecture which has shared buffers in this paper. The proposed architecture can reduce the overflows and cell conflicts through multiple paths and output ports even in the high load environments. Also, we proposed a cell splitting algorithm which handles the cell in the case of large fan-out, and a copy network to increase throughput by expanding the Lee's Broadcast Banyan Network(BBN). Cell copy uses the Boolean interval splitting algorithm and the multicast pattern of the cells according to the self-routing characteristics of the network. In the proposed copy network, we improve the problems such as overflow, cell splitting of large fanout, cell conflicts, etc., which were still existed in the Lee's network. The results of performance evaluation by computer simulation show that the proposed scheme has better throughput, cell loss rate and cell delay than the conventional method.

• Journal of Preventive Medicine and Public Health
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• v.53 no.2
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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.

• Korean Journal of Community Nutrition
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• v.16 no.6
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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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• v.10 no.3
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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%).

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.6
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• pp.1243-1257
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• 2019

With the emergence of the IoT environment, various smart devices provide consumers with the convenience and various services. However, as security threats such as invasion of privacy have been reported, the importance of security issues in the IoT environment has emerged, and in particular, the security problem of key management has been discussed, and the PUF has been discussed as a countermeasure. In relation to the key management problem, a protocol using MIPUF has been proposed for the security problem of the group key management system. The system can be applied to lightweight IoT environments and the safety of the PUF ensures the safety of the entire system. However, in some processes, it shows vulnerabilities in terms of safety and efficiency of operation. This paper improves the existing protocol by adding authentication for members, ensuring data independence, reducing unnecessary operations, and increasing the efficiency of database searches. Safety analysis is performed for a specific attack and efficiency analysis results are presented by comparing the computational quantities. Through this, this paper shows that the reliability of data can be improved and our proposed method is lighter than existing protocol.