• 항공우주시스템공학회지
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• 제13권5호
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• pp.9-15
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• 2019

In this paper, dynamic analysis of a nonlinear active vibration absorber is conducted with a time delay acceleration feedback to suppress the vibration of a nonlinear single degree of freedom primary system. The primary system consisting of linear and nonlinear cubic springs, mass, and damper is subjected to the multi-harmonic hard excitation with a parametric excitation. It is proposed to reduce the vibration of the primary system and the absorber by using a lead zirconate titanate (PZT) stack actuator in series with a spring in the absorber which configures as an active vibration absorber. The method of multiple scales (MMS) is used to obtain the approximate solution of the system under the internal resonance, subharmonic, superharmonic, and principal parametric resonance conditions simultaneously. Frequency and time responses of the system are investigated considering a delay in the feedback for the various parameters of the absorber configuration and controlling force.

• 대한소아치과학회지
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• 제48권1호
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• pp.12-20
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• 2021

이 연구의 목적은 소아 환자의 유구치 인접면 우식증 치료에 유동성 복합레진을 이용한 II급 와동 수복물의 생존율을 기성금속관과 비교하여 후향적으로 평가하는 것이다. 2015년 6월부터 2019년 8월까지 인접면 우식증으로 진단되어 유동성 복합레진과 기성금속관 수복 치료를 시행한 590명의 1,504개의 유구치에 대한 전자의무기록과 방사선사진을 조사하였다. 수집된 자료는 Kaplan-Meier method를 이용해 생존 분석을 하였다. 유동성 복합레진 수복된 치아의 1년 생존율은 98.5%, 3년 생존율은 87.7%, 평균 생존기간은 39개월이었으며, 기성금속관과 비교할 때 통계적으로 유의한 차이는 없었다(p = 0.896). 현 연구의 한계 내에서 유동성 복합레진을 이용한 II급 수복은 유구치 인접면 우식증 치료의 예지력 있는 선택지가 될 수 있다고 사료된다.

• Journal of Chest Surgery
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• 제32권7호
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• pp.648-652
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• 1999

배경: 액와절개술을 통한 폐기포절제술은 일차성 자연기흉의 수술적 치료로 많이 사용되어왔다. 대상 및 방법: 액와절개술시 사용되는 개흉기의 종류에 따른 임상성적을 비교하기 위하여 Naruke개흉기(N군)와 Finochieto개흉기(F군)를 이용하였다. 1997년 9월부터 1998년 9월 까지 대구 파티마 병원에서 일차성 자연기 흉에 있어서 액와절개술로 교정한 46례 중 Finochieto개흉기를 이용한 군이 22례 였으며, Naruke개흉기를 이 용한 군이 24례 였다. 결과: 수술시간 및 입원기간, 술 후 입원기간, 술 후 흉관 삽관 기간, 술 후 재발율이나 합병증에는 두 군간에 유의한 차이가 없었다. 결론: 일차성 자연기흉의 수술적 치료에 있어서 Naruke 개흉기 를 이용한 방법이 매우 유용할 것이다.

• 한국미생물·생명공학회지
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• 제24권6호
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• pp.647-651
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• 1996

The development of an enrichment method for the rapid and effective identification of Salmonella spp. in sewage or food was studied. As a growth factor for Salmonella, 10 mM cyclic adenosine monophosphate (cAMP) in trypticase soy broth with 0.6% yeast extract (TSBYE) increased cell number five-folds and 0.6% yeast extract in selenite broth increased cell number ten-folds of control. Bile salts in selenite broth was tested for the selection of S. enteritidis in a mixture with Staphylococcus aureus, Pseudomonas aeruginosa, Lactobacillus plantarum and Escherichia coli. The latter four strains were effectively inhibited at 0.1% bile salt. A two-step culture method was used to enrich Salmonella spp.; a primary-enrichment and secondary- enrichment culture. At a primary-enrichment step, selenite broth with 0.6% yeast extract and 10 mM cAMP was used, and at a secondary-enrichment step, 0.1% bile salt was additionally used. Culture times of a primary- enrichment and a secondary-enrichment step were 8 hr and 6 hr, respectively. In this procedure, cell number increased from 10$^{0.3}$ to 10$^{8.5}$ with inhibition of other strains within 14 hr. In the case of an initial cell concentrarion as low as 10$^{-2}$ cfu/ml, a cell number increased to 10$^{7}$ cfu/ml by using a 10 hr primary-enrichment and 6 hr secondary-enrichment procedure.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권3호
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• pp.1313-1336
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• 2020

Cognitive radio (CR) is regarded as an effective approach to avoid the inefficient use of spectrum. However, CRNs have more special security problems compared with the traditional wireless communication systems due to its open and dynamic characteristics. Primary user emulation attack (PUEA) is a common method which can hinder secondary users (SUs) from accessing the spectrum by transmitting signals who has the similar characteristics of the primary users' (PUs) signals, and then the SUs' quality of service (QoS) cannot be guaranteed. To handle this issue, we first design a multiple-phase energy detection scheme based on the cooperation of multiple SUs to detect the PUEA more precisely. Second, a joint SUs scheduling and power allocation scheme is proposed to maximize the weighted effective capacity of multiple SUs with a constraint of the average interference to the PU. The simulation results show that the proposed method can effectively improve the effective capacity of the secondary users compared with the traditional overlay scheme which cannot be aware of the existence of PUEA. Also the good delay QoS guarantee for the secondary users is provided.

• Parasites, Hosts and Diseases
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• 제43권2호
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• pp.61-64
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• 2005

The aim of the present study was to find out the number of students with enterobiasis and/or taeniasis in primary schools of Sivas. Among the 2,029 students in 6 primary schools, $316(15.6\%)$ were positive to Enterobius vermicularis eggs and $32(1.6\%)$ were positive to Taenia spp. eggs by the cellophane tape method. The egg positive rates of E. vermicularis and Taenia spp. ranged from $9.4\%\;to\;27.2\%\;and\;from\;0.8\%\;to\; 2.6\%$ respectively among six schools. The egg positive rate of E. vermicularis was found to be significantly different among these schools $(X^2=31.96,\;P<0.05)$, whereas there was no significant difference between the schools for Taenia spp. $(X^2=4.37;\;P>0.05)$. The rate $(18.7\%)$ of E. vermicularis in the urban slum regions was higher than the rate $(11.5\%)$ in the urban central regions $(X^2=19.20\;P<0.05)$. Above results demonstrate that the egg positive rate of E. vermicularis and Taenia spp. was still prevalent among primary school children.

• 가족자원경영과 정책
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• 제18권2호
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• pp.55-73
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• 2014

The purpose of this study is to examine the level of conspicuous consumption and resource-saving behavior in primary school students, and to discover the factors that influence these behaviors most strongly. The research was conducted in 2011 using a written questionnaires that were completed by 500 primary school students residing in Seoul, South Korea. The data was analyzed using statistical methods, including frequency, percentiles, means, standard deviation, Cronbach's coefficient, ANOVA, and hierarchical multiple linear regression analysis, using SPSS 18.0. As a result of these analyses, the average level of conspicuous consumption was found to be 2.65 relatively rational score. Next, it was shown that the conspicuous consumption of respondents differed significantly based on variables, such as allowances, family income, socialization process in childhood, family cohesion, and parental child rearing method. Finally, the greatest influences on respondent's resource-saving behavior was seen to be the child's socialization process in childhood, family cohesion, parental child rearing method, and conspicuous consumption. These variables must therefore all be considered when teaching primary school students and encouraging them to assume rational resource-saving habits in their daily lives.

• 한국간호교육학회지
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• 제25권4호
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• pp.459-470
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• 2019

Purpose: The purpose of this qualitative study was to identify the nature of precocious puberty and to explore what it means in primary schools. Methods: The participants of this phenomenological study were nine primary school girls who were diagnosed with precocious puberty and experienced hormone therapeutics, applying a convenience sampling method. Data were collected from July 2017 to January 2018 through individual in-depth interviews of the participants, including gestures, facial expressions and nonverbal means. The data analysis followed the method of Giorgi. Results: The study identified 37 concepts, 12 clusters, and five themes from experiences of precocious puberty. The essential five themes were as follows: 'ashamed and concealing experience', 'there is no therapeutics option', 'difficulties in the process of therapeutics', 'difficulties in daily life', and 'ambivalence toward therapeutics'. Conclusion: The findings of this study indicate physical, psychological and social difficulties faced by girls with precocious puberty. Based on this results of the study, it is necessary to develop nursing intervention programs focusing on healthy growth and development for children with precocious puberty.

• 보건교육건강증진학회지
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• 제19권3호
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• pp.97-105
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• 2002

This study attempts to develop a program for obesity prevention and management for students in primary, middle, and high school and was carried based on the program development process as suggested by Ewles and Simnett. Data were collected from September 1st to September 30th, 2000. The study method is as follows: 1) Reviewing the present obesity control programs practiced in primary, middle, and high school (196 schools total) in metropolitan, medium-sized, and small cities, 2) Surveying obesity students'(682 students total) perception of the obesity management in their school. 3) Reviewing the annual plan for obesity in primary, middle, and high schools 4) Analyzing the educational data (CD, VIDEO) for obesity The results are as below: I. The media researched related to obesity were mainly CD and video, aimed primarily primary school students and are biased in nature. 2. The results of how to manage obesity in students: the difficulty of obesity education in the primary school, is the arousal of a sense of shame among obese students and the lack of various educational data are the most. In the middle and high schools, a lack of various educational data, and no time or lack of time were prevailing concerns. Paramount in managing obesity is weight control, as answered by majority of primary, middle, and high school students. The major problem of obesity management is the non-cooperation of children. 3. Asked whether the weight controlling aspect of health care class was helpful or not, 51.4% of primary school students, and 71.6% of middle and high school students answered not. The most popular educational method used in health care class is the computer, with a 56.4% approval rating. Most 43.5% of respondents answered that they wanted the content of obesity management program to focus on how to lose weight. Therefore, based on the results, the obesity management program is constructed to the steps of assessment, planning, implementation, and evaluation. Assessment includes administering surveys on health needs among students and their parents and physique tests. Planning includes the set-up of long term and short term educational goal and the establishment of an operation system. Implementation includes education, exercise, behavior modification, and health service programs. Evaluation includes step-by-step evaluations for obesity reduction. After this study is conducted, the following should be further researched: More practical and systematic obesity management programs should be developed for the evaluation results. In addition, it is important to develop an appropriate media for obesity management the primary, middle and high school students.

• 제어로봇시스템학회논문지
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• 제10권5호
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• pp.458-463
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• 2004

This paper presents a fast IA(integer ambiguity) resolution method that determines the IA within short epochs with guaranteed reliability. Based on the fact that the search volume and the cost function are influenced by the selection of primary IAs in the plane intersection method, an IA resolution method is proposed that evaluates IA candidates repeatedly in an epoch with different combinations of primary IAs. In order to guarantee the reliability of the resolved IA with a certain probability, an inequality condition for selecting differencing operator is derived. Experiment results show that the proposed method consistently provides the true IA estimates within short time.