• Child Health Nursing Research
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• 제23권3호
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• pp.259-267
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• 2017

Purpose: This study was done to identify contraceptive practices in adolescent girls in South Korea and predictors of contraceptive practices. Methods: The study sample included 743 girls who had experienced sexual activity. Using statistics from the 12th (2016) Korea Youth Risk Behavior Web-based Survey, hierarchical logistic regression analysis was conducted. Results: The contraceptive practice rate for adolescent girls was 34%. Contraceptive practice was associated with 'age at first intercourse' and 'sexual intercourse after drinking'. For adolescent girls who had early sexual initiation and drank alcohol before sexual intercourse there was a tendency to reduce the practice of contraception. Conclusion: It is necessary to provide practical sex education to improve the practice of contraception in these adolescents. In addition, adolescent girls should be encourage to delay their first intercourse. The results of this study can also be used to develop education interventions regarding healthy sexuality behaviour including the practice of contraception.

• 대한방사성의약품학회지
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• 제3권2호
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• pp.116-121
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• 2017

To overcome the low reactivity and solubility of alkali metal fluorides (MFs), various types of phase transfer catalysts (PTCs) have been developed over the last decades. However, since the fluoride activated by such PTC sometimes has a strong basicity, it may cause various side reactions such as elimination reaction or hydroxylation reaction in the nucleophilic fluorination reaction. Also, they may cause separation problems in the compound purification process. In recent advanced study, various PTCs have been developed to solve these problem of conventional catalyst. In this review, we would like to introduce three kinds of novel multifunctional organic catalysts such as bis-tert-alcohol-functionalized crown-6-calix[4]arene (BACCA), easy separable pyrene-tagged ionic liquid (PIL) by reduced graphene oxide (rGO), and tri-tert-butanolamine organic catalyst.

• Bulletin of the Korean Chemical Society
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• 제35권6호
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• pp.1590-1600
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• 2014

Cinchona-based bifunctional catalysts have been extensively employed in the field of organocatalysis due to the incorporation of both hydrogen-bonding acceptors (quinuclidine) and hydrogen-bonding donors (e.g., alcohol, amide, (thio)urea and squaramide) in the molecule, which can simultaneously activate nucleophiles and electrophiles, respectively. Among them, cinchona-derived (thio)urea and squaramide catalysts have shown remarkable application potential by using their bifurcated hydrogen bonding donors in activating electrophilic carbonyls and imines. However, due to their bifunctional nature, they tend to aggregate via inter- and intramolecular acid-base interactions under certain conditions, which can lead to a decrease in the enantioselectivity of the reaction. To overcome this self-aggregation problem of bifunctional organocatalysts, we have successfully developed a series of sulfonamide-based organocatalysts, which do not aggregate under conventional reaction conditions. Herein, we summarize the recent applications of our cinchona-derived sulfonamide organocatalysts in highly enantioselective methanolytic desymmetrization and decarboxylative aldol reactions. Immobilization of sulfonamide-based catalysts onto solid supports allowed for unprecedented practical applications in the synthesis of valuable bioactive synthons with excellent enantioselectivities.

• 대한가정학회지
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• 제38권8호
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• pp.53-68
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• 2000

This study examines family life problems & solution of married women in Chonbuk area as a part of study on family life Issues. Data were collected by questionnaires. The sample consisted of 1142 married women. The major findings were summarized as follows : (1) The degree of recognition about family life problem is rated economic life > woman's parents-in-law> woman's real parents> spouse> children related problems. (2) In the family conflict solution types, the most used types is a rational. (3) The degree of recognition about the family violence is rated abusive languages of husband>husband behavior under the influence of alcohol wife's child abuse>husband's child abuse>abusive languages of wife>battered wife. (4) The kins are still considered the primary source for functions of personal support. Also, the needs for the children related equipments is higest among the public support equipments.

• 제어로봇시스템학회논문지
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• 제1권2호
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• pp.119-126
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• 1995

The purpose of this study is to develop the technique of energy recovery and energy saving by using the optimization of heat exchanger network synthesis. This article proposes a new method of determining the optimal target of a heat exchanger network synthesis problem of which data feature multiple pinch points. The system separation method we suggest here is to subdivide the original system into independent subsystems with one pinch point. The optimal cost target was evaluated and the original pinch rules at each subsystem were employed. The software developed in this study was applied to the Alko prosess, which is an alcohol production process, for the synthesis of heat exchanger network. It was possible to save about 15% of the total annual cost.

• 한국자동차공학회논문집
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• 제3권6호
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• pp.162-175
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• 1995

Exhaust emissions in diesel engine are affected by fuel properties, but the reason for this is not clear. Especially, the recent strong interest in using low-grade fuel such as used vegetable oil as alternative diesel fuel demands extensive investigation in order to clarify the exhaust emissions. The purpose of this study is to evaluate the feasibility of a used vegetable oil as an alternative fuel in a diesel engine in terms of exhaust emissions. The emission concentration of used vegetable oil such as formaldehyde and acrolein is two times than that of diesel fuel. However, since that of alcohol is ten times than that of used vegetable oil and that concentration is very low, it is not a problem for human health.

• Archives of Pharmacal Research
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• 제10권4호
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• pp.239-244
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• 1987

An efficient and inexpensive method for the substitution of allylic hydroxyl group with fluoride, without allylic rearrangement, and elimination was developed. This method consists of treating an allylic alcohol with methylithium, followed by p-toluene sulfonyl fluoride, lithium fluoride and 12-Crown-4. This methodology was proved to be efficient by preparting geranyl fluoride, neryl fluoride, cinnamyl fluoride, E, E-farnesyl fluoride, retinyl fluoride and 4-fluoro-2-methyl-6-(ptolyl)-2-heptene.

• 말소리와 음성과학
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• 제3권1호
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• pp.111-116
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• 2011

The purpose of this study was to analyze the association between self-reported voice problems and voice disorders in the Korean adult population. Data were collected from the 4th Korea National Health and Nutritional Examination Survey (2008) from 3,135 subjects (1,310 men and 1,825 women) aged 19 years and older. Multi-nominal logistic regression analyses were used to examine the association between self-reported voice problems and voice disorders in the Korean adult population. Adjusting for covariates (age, sex, education level, job, smoking, alcohol drinking, thyroid disorders, pain and discomfort during the last 2 weeks), self-reported voice problems included independently associated functional voice disorders (OR=4.70, 95% CI: 3.14-7.03) and organic voice disorders (OR=3.89, 95% CI: 1.57-9.65). The results of the present study verified that self-reported voice problems are valuable indicators for voice disorders. Further research is needed to ascertain the effect of self-reported voice problems on voice disorder in adults.

• Journal of information and communication convergence engineering
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• 제1권1호
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• pp.27-30
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• 2003

Electrophoretic deposition (EPD) of alcohol YBCO suspensions on the Ag wire electrode is studied. Poly(ethylene glycol) was coordinated to a structure formed by the EPD process with YBCO particles. The suspension is characterized in terms of zeta potential and conductivity. The d.c electric fields of 200-300 V/cm are applied for 1-10 min. The optimal condition for the EPD allows modifying the properties and microstructure of the deposited films. Superconducting coatings with nanometer-sized pores and a preferred orientation along the c-axis were prepared from the result with chemically modified precursor solution. In contrast, YBCO coatings of submicrometer-sized pores and randomly orientated grains were prepared from the solution without PEG.

• Journal of Preventive Medicine and Public Health
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• 제55권6호
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• pp.499-505
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• 2022

Despite advances in medicine and preventive strategies, fewer than 1 in 5 people with hypertension have the problem under control. This could partly be due to gaps in fully elucidating the etiology of hypertension. Genetics and conventional lifestyle risk factors, such as the lack of exercise, unhealthy diet, excess salt intake, and alcohol consumption, do not fully explain the pathogenesis of hypertension. Thus, it is necessary to revisit other suggested risk factors that have not been paid due attention. One such factor is psychosocial stress. This paper explores the evidence for the association of psychosocial stressors with hypertension and shows that robust evidence supports the role of a chronic stressful environment at work or in marriage, low socioeconomic status, lack of social support, depression, anxiety, post-traumatic stress, childhood psychological trauma, and racial discrimination in the development or progression of hypertension. Furthermore, the potential pathophysiological mechanisms that link psychosocial stress to hypertension are explained to address the ambiguity in this area and set the stage for further research.