• Title/Summary/Keyword: using frequency

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A Study on the Tendency of Dose value According to Dose calibrator Measurement Depth and Volume (Dose calibrator 측정 깊이와 용량의 변화에 따른 선량 값의 성향에 대한 고찰)

  • Kim, Jin Gu;Ham, Jun Cheol;Oh, Shin Hyun;Kang, Chun Koo;Kim, Jae Sam
    • The Korean Journal of Nuclear Medicine Technology
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    • v.24 no.1
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    • pp.20-26
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    • 2020
  • Purpose It is intended to figure out the errors derived from changes in depth and volume when measuring the Standard source and 99mTc-pertechnetate by using a Dose calibrator. Then recommend appropriate measurement depth and volume. Materials and Methods As a Dose calibrator, CRC-15βeta and CRC-15R (Capintec, New Jersey, USA) was used, and the measurement sources were 57Co, 133Ba, 137Cs and 99mTc-pertechnetate was also adopted due to its high frequency of use. The Standard source was respectively measured the changes according to its depth without changing the volume, in a range of 0 cm to 15 cm from the bottom of the ion chamber. 99mTc-pertechnetate was measured at each depth by changing the volume with 0.1 mL, 0.3 mL, 0.5 mL, 0.7 mL and 0.9 mL Respectively. And the depth range was from 0 cm to 15 cm at the bottom of the ion chamber. Results In the case of Standard source 57Co, 133Ba, 137Cs and 99mTc-pertechnetate, there were significant differences according to the measurement depth(p<0.05). 99mTc-pertechnetate has a negative correlation coefficient according to the depth, and the error of the measured value was negligible at a depth from 0 cm to 7 cm at 0.3 mL and 0.5 mL, and the range of error increased as the volume increased. Conclusion In clinical practice, it is sometimes installed differently than the Standard depth recommended by the equipment company. If it's measured at the recommended depth and volume, it could be thought that unnecessary exposure of the operator and the patient will be reduced, and more accurate radiation exams will be possible in quantitative analysis.

The Impact of monsoon Rainfall (Changma) on the Changes of Water Quality in the Lower Nakdong River (Mulgeum) (장마기의 강우가 낙동강 하류 (물금) 수질에 미치는 영향)

  • Park, Sung-Bae;Lee, Sang-Kyun;Chang, Kwang-Hyeon;Jeong, Kwang-Suek;Joo, Gea-Jae
    • Korean Journal of Ecology and Environment
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    • v.35 no.3 s.99
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    • pp.160-171
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    • 2002
  • The impact of summer monsoon on water quality of the lower Nakdong River was evaluated during the summer (June-August) in 1997. Several limnological variables were measured in the interval of $1{\sim}3$ day using an automatic monitoring system (Hydrolab $Recorder^{TM}$) to detect water quality changes caused by rainfall on onehour basis. During the monsoon period (from late June to mid July), 5 times of major rainfall events of >50 mm were recorded in the river basin. Dynamic changes of water quality were observed during the monsoon, and the first rainfall event (June$25{\sim}27$) had a significant influence on the water quality at the lower part of the river. All Parameters were largely changed due to the first rain event, and the changed level was maintained until the end of monsoon period. Nutrient concentrations and turbidity increased and values of the other parameters were declined as a result of water dilution. This rainfall event, Changma, is a meteorological phenomenon caused by the East-Asian monsoon climate. The magnitude and frequency of the rainfall during the early monsoon play an important role in change of water quality and ecosystem characteristics of large river systems.

Comparison of the SNR in the MR images on dental implant material (치아 임플란트 재료에 따른 자기공명영상의 SNR 비교)

  • Kim, Dong-Hyun;Ko, Seong-Jin;Ye, Soo-Young
    • Journal of the Institute of Convergence Signal Processing
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    • v.16 no.4
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    • pp.149-155
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    • 2015
  • Tooth implant is located in oral cavity and affects neck, skull base, and facail image. These magnetic inhomogeneities are usually frequency encoding direction which cause artifacts due to change of signal strength and geometric distortion. First, to evaluate signal to noise ratio (SNR) of magnetic resonance image caused by tooth implant this study uses meat phantom which is similar to human body and is consisted with fat, muscle, and water to measure signal to noise ratio. Second, signal to noise ratio by using custom-made fixed phantom is measured, and then signal to noise ratio size of different tooth implant types is compared and analyzed. The measured signal to noise ratio values of Brushite, HSA, Metal, and RBM for meat phantom were 2.76, 2.22, 1.88, and 1.57 on T1 SE, 1.88, 1.78, 1.65, and 1.79 on T2 FLAIR, 2.28, 2.25, 2.88, and 2.05 on T2 FSE, and 2.74, 1.94, 1.67, and 1.48 on T2 GRE. The measured signal to noise ratio values of Brushite, HSA, Metal, and RBM for fixed water phantom were 1.2, 1.06, 1.12, and 1.22 on DWI, 1.93, 1.87, 1.93, and 2.06 T1 SE, 1.83, 1.76, 1.82, and 1.92 on T2 FLAIR, 1.85, 1.79, 7.86, and 1.97 on T2 FSE, and 1.97, 1.93, 1.99, and 2.06 on T2 GRE. By considering through the results, patients and dentists need to consider some impacts from testing many aspects although their main purpose of having tooth implants is a dental restoration. Moreover, depending on the tooth implant characteristics of individual patients this study results can be used as baseline data when choosing test protocol.

Frequency and Pattern of Partial Thickness Rotator Cuff Tear in SLAP Lesions (SLAP 병변에서 회전근 개 부분층 파열의 빈도와 양상)

  • Cho, Duck-Yun;Yoon, Hyung-Ku;Kim, Hyoung-Jun;Rhee, Seung-Young;Kim, Jae-Hwa
    • Journal of the Korean Arthroscopy Society
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    • v.8 no.2
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    • pp.119-123
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    • 2004
  • Purpose: The purpose of this study is to check the range of motion of shoulder and inverstigate the frequencies and patterns of partial thickness rotator cuff tear in SLAP lesions. Materials and Methods: Forty-six patients, forty-seven cases who had SLAP lesions at shoulder arthroscopy were analyzed spectively using the medical records, intra-operative arthroscopic photo & video for SLAP lesions and rotator cuff articular side partial tear. Under the interscalene anesthesia, the range of notion of foreward elevation, internal rotation and external rotation was measured on fixed scapula and 90 degree abduction of the shoulder. Results: The rang of Motion are 150 degree on foreward elevation, 65.5 degree on external rotation, 61.7 degree on internal rotation. By Snyder's classification, type ll SLAP lesion is noted in 24 cases (five cases in type 1, one case in type IV). Rotator cuff articular side partial tear is noted in 24 cases ( one case in type I, 22 cases in type II, one case in type IV SLAP). All the rotator cuff articular side partial thickness tear were located in the anterior part of the supraspinatus. Conclusion: The rotator cuff partial thickness tear is mostly noted on the articular side and frequently found in the relatively more unstable type of SLAP lesions. So we consider that SLAP lesion may be a one of the causes for partial tear of the rotator cuff articular side.

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Effectiveness of Home Economics Class on self-esteem and stress of middle school students (가정과수업이 중학생의 자아존중감과 스트레스에 미치는 효과)

  • Park, Mi Jeong
    • Journal of Korean Home Economics Education Association
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    • v.29 no.3
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    • pp.15-32
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    • 2017
  • This study investigated the effectiveness of home economics class on self-esteem and stress of middle school students. Data were collected from self-reported inventory of the middle school students in Y city of Gyeonggi province and 165 data copies were used for analyses. Data were analyzed for frequency, percentage, mean, standard deviation, Cronbach's ${\alpha}$, t-test, corelation and dependent t-test using SPSS/PC 18.0 program. The results were as follows. First, the average of positive self-esteem was 2.74 and that of negative self-esteem was 1.90 on a 4 Likert scale. The range of stress level was 1.88~2.48 on a 5 Likert scale. Life satisfaction was 3.90 and helpfulness of home economics class was 3.89 on a 5 point Likert scale, which means moderately high. Second, examining differences in variables according to gender, there were statistically significant differences in stress regarding family for both pre- and post-tests. Third, helpfulness of home economics class had positive correlation with positive self-esteem and life satisfaction and had negative correlation with negative self-esteem and stress, which means that home economics class enhance life satisfaction and positive self-esteem and lessen negative self-esteem and stress of middle students. Fourth, as a result of comparison of pre and post-tests, positive self-esteem, life satisfaction, and helpfulness of home economics class increased statistically after home economics classes, while stress regarding school life decreased statistically. Even though students' growth and changes resulting from learning other subjects were not controlled, it was meaningful that effectiveness of home economics class were examined and helpful information for enhancing perception of home economics education were provided.

Effectiveness of Internet-based Interventions on HbA1c Levels in Adult Patients with Diabetes: A Meta-Analysis of Randomized Controlled Trials (인터넷 기반 중재프로그램을 통한 성인 당뇨 환자의 HbA1c 중재효과: 메타분석)

  • Jung, Chang Suk;Noh, Hyun Jung;Gu, Min Jeong;Kim, Yi Young;Lee, Soon Young
    • Journal of health informatics and statistics
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    • v.43 no.4
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    • pp.307-317
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    • 2018
  • Objectives: This study aimed to verify the effectiveness of Internet-based intervention programs for adults with diabetes by conducting a meta-analysis of studies conducted since 2000. Methods: We conducted a systematic review of research papers published in domestic and overseas journals from January 2000 to December 2015, and selected 9 papers that met the analysis criteria. Data analysis was performed using the open source statistical software R 3.5.0, to analyze the effectiveness of Internet-based interventions on experimental and control groups. Results: The analysis showed that intervention programs for controlling HbA1c levels in adult patients with diabetes most commonly comprised 7 sessions on Internet-based management (77.8%), and the most common frequency of application of intervention programs was 4 session in 6 months (33.4%). The present meta-analysis revealed statistically significant effects of Internet-based intervention activities (SMD = 0.92, 95% CI 0.45-1.40). The analysis of the effect size according to the intervention period showed that the 3-month, 6-month, and 12-month interventions reported in eight studies (89%) had a high effect on the Internet-based intervention group. Conclusions: The results of this study confirm the effectiveness of Internet-based intervention programs for adult patients with diabetes. The need for research on the utilization of Internet-based intervention programs for the steady management of diabetes, a chronic disease; for the development of specific guidelines for intervention activities; and for establishing appropriate protocols are acknowledged.

A study on Perception and Response Strategy of Korean Ship Owners on Global Sulphur Cap 2020 (황산화물(SOx) 배출 저감 규제에 대한 국적선사의 인식과 대응 전략에 관한 연구)

  • Lee, Choong-Ho;Kim, Hyun-Jung;Park, keun-Sik
    • Journal of Korea Port Economic Association
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    • v.34 no.4
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    • pp.141-160
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    • 2018
  • In this paper, to analyze the perception and response strategy of Korean ship owners on Global Sulphur Cap 2020, examined the IMO environmental regulation status focusing on MARPOL Annex VI regulation about air pollution prevention, technological measures to reduce SOx emission, shipping industry and management status of Korean ship owners. First of all, the questionnaire was conducted for Korean ship owners after selecting the evaluation factors. The purpose of this study was to investigate the difference of the perception and response strategy of Korean ship owners by corporation size and main vessel type using frequency and cross analysis. It is confirmed that various researches on SOx emission reduction have been carried out from various points of view at home and abroad. In this study, existing studies related to technical factors for regulatory response and economics analysis were examined and evaluation factors were selected. As a result of analysis, it is found that large-sized shipping companies are more prepared for regulatory response than small and medium-sized bulk carrier owners. There were similar perception and the direction of response strategy about the impacts by corporation size and main vessel type. In about two years to be implemented in 2020, It is necessary to find an appropriate response strategy based on the support policy of the government and related organizations and the systematic analysis of the ship owners. Through this study, although the difference between the perception and response strategy of the ship owners by corporation size and main vessel type was understood, it was found that there were limitations on specific response strategy and corporate data collection. In future research, we should overcome the limitations of this study and conduct an in-depth study.

Time-Lapse Crosswell Seismic Study to Evaluate the Underground Cavity Filling (지하공동 충전효과 평가를 위한 시차 공대공 탄성파 토모그래피 연구)

  • Lee, Doo-Sung
    • Geophysics and Geophysical Exploration
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    • v.1 no.1
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    • pp.25-30
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    • 1998
  • Time-lapse crosswell seismic data, recorded before and after the cavity filling, showed that the filling increased the velocity at a known cavity zone in an old mine site in Inchon area. The seismic response depicted on the tomogram and in conjunction with the geologic data from drillings imply that the size of the cavity may be either small or filled by debris. In this study, I attempted to evaluate the filling effect by analyzing velocity measured from the time-lapse tomograms. The data acquired by a downhole airgun and 24-channel hydrophone system revealed that there exists measurable amounts of source statics. I presented a methodology to estimate the source statics. The procedure for this method is: 1) examine the source firing-time for each source, and remove the effect of irregular firing time, and 2) estimate the residual statics caused by inaccurate source positioning. This proposed multi-step inversion may reduce high frequency numerical noise and enhance the resolution at the zone of interest. The multi-step inversion with different starting models successfully shows the subtle velocity changes at the small cavity zone. The inversion procedure is: 1) conduct an inversion using regular sized cells, and generate an image of gross velocity structure by applying a 2-D median filter on the resulting tomogram, and 2) construct the starting velocity model by modifying the final velocity model from the first phase. The model was modified so that the zone of interest consists of small-sized grids. The final velocity model developed from the baseline survey was as a starting velocity model on the monitor inversion. Since we expected a velocity change only in the cavity zone, in the monitor inversion, we can significantly reduce the number of model parameters by fixing the model out-side the cavity zone equal to the baseline model.

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우리나라 농촌지역의 출산조절행태 및 출산조절행위의 결정요인 분석

  • Chung, Kyung-Hee;Han, Seung-Hyun;Bang, Sook
    • Korea journal of population studies
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    • v.11 no.2
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    • pp.33-53
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    • 1988
  • This study aimed at developing a desirable family planning policy and strategy by examining the current status of family planning practice in rural Korea and by indentifying the crucial factors which affect fertility control behavior. For this purpose, an analytical study was conducted, using the survey data collected in July 1985, on an interview basis, on 1, 440 married women living in the Soyi, Wonnam and Maingdong townships of Eumseong County(in North Chungcheong Province). This study population has the typical characteristics of rural areas, and the results of the analysis can be summarized as follows: 1. In regard to the demographic characteristics of the study population : their average age at marriage was 23.7, they had an average of 2.6 children( 1.3 boys, 1.3 girls) :10% experienced the death of their child (ren) :14% had spontaneous abortion(s) :4% weathered stillbirth(s) :35% went through induced abortion (s) : and 5.5% were currently pregnant. The average of their ideal numbers of children was 2.2, while 44% felt that they must have a son. 2. Looking at the contact rate with medical & health institutions, over the past 1 year, the visit rate to health subcenters was 43.7%, while 26.9% visited the (county) health center :59.6% had been to private clinics : and 41.5% went to the Soonchunhyang - Eumsung hospital : thus showing a relatively high rate of accessibility. 3. The utilization rate of family planning services was 76.5%, with tubectomy being the most prominent method at 52.3%, while the informants were health workers in 54.2% of the acceptors. Of the 8.4% who discontinued the use of contraceptive methods, only 26% did so due to want for pregnancy, natural infertility (meno - pause), or other reasons, while the remaining 74% stopped usage on account of side effects, failure in the methods themselves, and inconvenience of use, thus pointing to a situation where the proper choice of family planning methods have not yet been made. It can be noted that there is a strong motivation for early birth stopping as 35.3% practice family planning even with only one child, of which 38.3% have had sterilization operations. According to results of a multiple regression analysis, among the variables affecting contraception usage the most significant variable was the number of sons. 4. 34.8% experienced induced abortions. It was shown as a result of multiple regression analysis that the number of children and attitudes toward induced abortions extensively affected their frequency of abortions conducted. 5. In the regard to the relation between family planning and induced abortions, 33.7% of the women used both, while 52.0% of them used only the former(family planning), with only 1.4 % utilizing solely the latter(abortion), and 12.9% totally abstaining from fertility regulation : again, the discriminant analysis indicated that the choice of family planning and/or induced abortion was determined by the number of children and attitudes toward induced abortion. In view of the above mentioned results, the following are some comments and suggestions concerning problems related to the current family planning policies, in Korea : 1. It is difficult to expect a further quantitative expansion in family planning program operations, as there has been an excessive supply of target-oriented sterilization operations on women. From a maternal and child health care point of view, it will be desirable to have a diversification of service points in the future where family planning methods may be properly chosen, so that choices of methods which suit the mothers' characteristics and tastes may be made by the individuals themselves by strengthening their quality of family planning information services. 2. Along with the strengthening of the qualitative improvement of family planning services policies must be implemented to effectively promote the moral (ethical) deterrents to induced abortions and to preference for sons. From a maternal care standpoint, the social permissive norm toward induced abortion must be modified, and the bias towards son must be analyzed as the women with more daughters have a lower rate of family planning acceptance. Such changes in attitudes, however, can not be hoped to be accomplished with ad hoc policies, but will only be possible when an enhancement of the women's status(within the society) is brought about in a long - term perspective.

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Relationship between Access to Lewd Internet Contents by Middle School Students and Their Awareness of Sex (중학생의 인터넷음란물 접속과 성 의식의 관계)

  • Lim, Jong-In;Choi, In-Sook
    • The Journal of Korean Society for School & Community Health Education
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    • v.4
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    • pp.117-139
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    • 2003
  • The purpose of this research lies in presenting logical viability for the measures that curtail access to lewd Internet contents by middle school students amidst the reality in which lewd contents are circulated freely through the Internet, a medium that the middle school students find most easy to access. In order to establish right form of awareness towards sex, this research identified the ways they access the lewd Internet contents, their reaction after the exposure to those contents, their knowledge of sex, their concerns regarding sex and their accessibility to sexual activities in order to conduct a comparative analysis on the relationship between lewd Internet contents and their awareness of sex. First, realities of accessing lewd Internet contents and reactions according to the demographics of middle school students There isa significant difference in the experience of accessing lewd Internet contents in terms of gender. Mostly, male students tend to access the contents more. As for the way they access the lewd Internet contents, both male and female students replied that they access through spam mail of lewd nature. Thus, measures to address this problem are needed urgently. As to when they first accessed the lewd contents, most of the research subjects replied that they accessed either in elementary school period or in the early middle school period. This shows that most of the students got exposed to lewd contents even before they could establish positive, correct awareness of sex. Thus, there is a risk that they may formulate wrong kind of sexual awareness. Accordingly, it is necessary to develop measures through focused sex education. Students are divided into two groups according to the time they spend on the contents averagely: those who spend over one hour and those who spend less than an hour on the lewd contents. If the students spending longer hours are not to be checked and properly guided, it may lead to increasing cases of sexual delinquencies due to their wrongly formed awareness of sex. When the question of existence(non-existence) of guardian was addressed, students with both parents tend to access the lewd Internet contents in a more diverse manner and tend to access more compared to those students from single parent or no-parent families. Accordingly, guardians need to pay attention to how their children are using the Internet. Second, awareness of sex depending on the middle school students' demographics In case of sexual knowledge, middle school students shows relatively high level of knowledge. In particular, female students are found more knowledgeable than male students, and the students in upper years are more knowledgeable as well. As a result, this research recommends that the students in lower years should be guided with more basc and detailed information, while those in upper years need to be taught to form and express their own thoughts and attitudes and to build up independence on this matter. In case of worries about sex, both male and female students don't worry too much about it. However, male students are more concerned about sex than female students in a more diverse ways. As for the differences by academic year, concerns for sex increase, as students get older. Accordingly, sex education that helps establish sound perception of the opposite sex and that focuses on the etiquettes that one must adhere to at the presence of the opposite sex need to be conducted against middle school students. In case of accessibility to sex, male students manifest higher tendency than female students. As for the differences by academic year, those in the first and second years show higher accessibility than those in their third year. In general, younger students tend to be more open-minded toward sex. Accordingly, students in lower academic years need to undergo basic knowledge oriented sex education, whereas those in upper academic years need to undergo discussion centered sex education where they subject to questions regarding their attitude and opinion. Third, relationship between the reactions after the exposure to the lewd Internet contents and their awareness of sex As the frequency of contact with lewd Internet contents increases, awareness of sex increases as well. Thus, the lewd Internet contents contribute to the increase in students' concern for sex as well as increase in accessibility to sex, which eventually become barriers to students' establishment of a healthy perception of sex. Reactions to sex after the exposure to lewd Internet contents and awareness of sex indicate a significant correlation. However, negative correlation is manifested with knowledge of sex. Thus, it is possible to know that the greater access to lewd Internet contents does not necessarily translate into increase in knowledge of sex. However, the study showed there is a correlation between concerns for sex and the level of accessibility to sex. In more detail, the more reactions to the contents they show, the more concerns for sex they have and the more positively they take acceptability to sex. Moreover, it is necessary to develop necessary measures since textbooks today do not include measures needed to address the lewd Internet contents. Given the above findings, it is necessary to continue to complement structural measures in order to prevent easy access of lewd Internet contents by middle school students. Moreover, it is necessary to be considerate of the students so that they themselves can form a healthy Internet culture and grow up within positive framework for the sex education.

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