• Title/Summary/Keyword: high frequency

Search Result 18,913, Processing Time 0.062 seconds

The Effect of School Library-Assisted Instruction on Self-Directed Learning Ability in Home Economics Education (가정과 교육에서 학교도서관 활용수업이 중학생의 자기주도적 학습능력에 미치는 효과)

  • Lee, Hyo-Soon;Yoo, Tae-Myung
    • Journal of Korean Home Economics Education Association
    • /
    • v.19 no.4
    • /
    • pp.201-218
    • /
    • 2007
  • This study is a quasi-experimental study to find out the effect of school library-assisted instruction on middle school students' self-directed learning ability in Home Economics Education. For this purpose, the following research questions were established. 14 hours of school library-assisted instruction and traditional lecture were carried out to 164 9th grade female students(82 of experimental group, 82 of comparison group) of a girls' middle school in Jinju, Gyeongnam. To verify the instructional effect, a pre-test and a post-test for self-directed learning ability were carried out. SPSS 12.0 was used for statistical analysis. For statistical analysis, reliability analysis, frequency analysis, x2-test, t-test, repeated measures-ANOVA, and bivariate analysis were used. The results of this research were as follows: First, there was a statistically significant difference between experimental group and comparison group in the self-directed learning ability in all the subordinate items. Second, the change of self-directed learning ability by grade within the experimental group showed no interactional effect in all the sub-items except problem solving ability. Problem solving ability showed a meaningful difference in the rate of grade rising in accordance with academic achievement level and a higher synergy effect was shown in the low academic achievement group. Third, the experimental group showed a higher rate of rising in the self-directed learning ability than the comparison group, and the low academic achievement group showed a higher rising rate of grade than the high academic achievement group. Based on the results of this research, we concluded that the school library-assisted instruction was effective in enhancing middle school students' self-directed learning ability especially for the low academic achievement group.

  • PDF

A study on the interrelation of influential factors in organizational conflict and organizational commitment (병원종사자의 조직갈등 및 조직몰입에 영향을 미치는 요인에 관한 연구)

  • Kim, Young-Hoon;Kim, Han-Joong;Cho, Woo-Hyun;Lee, Hae-Jong;Park, Chong-Yon;Lee, Sun-Hee
    • Korea Journal of Hospital Management
    • /
    • v.7 no.1
    • /
    • pp.41-63
    • /
    • 2002
  • The purpose of this study is to analyze the interrelation of influential factors in organizational conflict and organizational commitment. The data for this study were collected through a self-administered survey with a structured Questionnaire to 1,167 subjects from several nursing staff members, administration staff members and medical technicians of six hospitals. In this analysis frequency test, t-test, ANOVA, hierarchical multiple regression and structural equation model were used. The main findings of this study are as follows. 1. Factors which influence organizational conflict were analyzed. The type of occupation and the year of service were socio-demographic variables which influenced organizational conflict positively. Adjusted R square was 0.03. Perceptions on organizational structure and organizational culture were analyzed with two- level variables that were added. The findings were as follows. Adjusted R square increased to 0.25. The year of service, internal process culture and rational goal culture were positive variables. The design of organizational structure, human relations culture and open system culture were negative variables. 2. Variables which influence organizational commitment were analyzed. Age and the year of service were positive variables, while academic background based on high school education was a negative variable. Adjusted R square was 0.16. Perceptions on organizational structure and organizational culture were analyzed with two-level variables that were added. The findings were as follows. The characteristics of organizational structure, human relations culture and organizational culture were positive variables. Adjusted R square increased to 0.55. The variables of organizational conflict were added in 3 steps. Findings were as follows. The variables of hierarchical conflict showed negative influence and were included in two-level influential variables. Adjusted R square increased to 0.56. 3. Structural equation model was analyzed in order to examine the relation between organizational structure and the variables of organizational culture, organizational conflict and organizational commitment. Thirteen path coefficients out of seventeen path coefficients were significant. Age had negative influence on organizational conflict and positive influence on organizational commitment. The year of service had positive influence on organizational conflict and organizational commitment. The design of organizational structure, human relations culture and open system culture had negative influence on organizational. conflict. They had positive influence on organizational commitment. Internal process culture and rational goal culture had positive influence on organizational conflict. Organizational conflict had negative influence on organizational commitment. The squared multiple correlation of this model was 25.1% in organizational conflict and 52.7% in organizational commitment. The conclusion of this study is as follows. Factors in organizational structure and organizational culture, rather than socio-demographic factors, had a stronger influence on the organizational conflict and organizational commitment of hospitals. In order to decrease organizational conflict, to increase organizational commitment and to maximize the effectiveness of hospital management, it is necessary to understand the overall relation between organizational structure, organizational culture, organizational conflict and organizational commitment, with the effort of improving personalized factors and individual factors of organization management.

  • PDF

Dynamic Behavior of Reactor Internals under Safe Shutdown Earthquake (안전정기지진하의 원자로내부구조물 거동분석)

  • 김일곤
    • Computational Structural Engineering
    • /
    • v.7 no.3
    • /
    • pp.95-103
    • /
    • 1994
  • The safety related components in the nuclear power plant should be designed to withstand the seismic load. Among these components the integrity of reactor internals under earthquake load is important in stand points of safety and economics, because these are classified to Seismic Class I components. So far the modelling methods of reactor internals have been investigated by many authors. In this paper, the dynamic behaviour of reactor internals of Yong Gwang 1&2 nuclear power plants under SSE(Safe Shutdown Earthquake) load is analyzed by using of the simpled Global Beam Model. For this, as a first step, the characteristic analysis of reactor internal components are performed by using of the finite element code ANSYS. And the Global Beam Model for reactor internals which includes beam elements, nonlinear impact springs which have gaps in upper and lower positions, and hydrodynamical couplings which simulate the fluid-filled cylinders of reactor vessel and core barrel structures is established. And for the exciting external force the response spectrum which is applied to reactor support is converted to the time history input. With this excitation and the model the dynamic behaviour of reactor internals is obtained. As the results, the structural integrity of reactor internal components under seismic excitation is verified and the input for the detailed duel assembly series model could be obtained. And the simplicity and effectiveness of Global Beam Model and the economics of the explicit Runge-Kutta-Gills algorithm in impact problem of high frequency interface components are confirmed.

  • PDF

Temperature-dependent Development and Its Model of the Greenbug, Schizaphis graminum (Rondani) (Homoptera: Aphididae) (보리두갈래진딧물 [Schizaphis graminum (Rondani)]의 온도발육과 발육모형)

  • Lee, Jang-Ho;Kim, Tae-Heung;Kim, Ji-Soo;Hwangn, Chang-Yeon;Lee, Sang-Guei
    • Korean journal of applied entomology
    • /
    • v.46 no.2
    • /
    • pp.213-219
    • /
    • 2007
  • The development of Schizaphis graminum (Rondani) was studied at various constant temperatures ranging from 15 to $32.5^{\circ}C$, with $65{\pm}5%$ RH, and a photoperiod of 16L:8D. Mortality of the $1_{st}-2_{nd}\;and\;the\;3_{rd}-4_{th}$ stage nymphs were similar at most temperature ranges while at high temperature of $32.5^{\circ}C$, more $3_{rd}-4_{th}$ stage individuals died. The total developmental time ranged from 13.8 days at $15^{\circ}C$ to 4.9 days at $30.0^{\circ}C$ suggesting that the higher the temperature, the faster the development. However, at higher end temperature of $32.5^{\circ}C$ the development took 6.4 days. The lower developmental threshold temperature and effective accumulative temperatures for the total immature stage were $6.8^{\circ}C$ and 105.9 day-degrees, respectively and the nonlinear shape of temperature related development was well described by the modified Sharpe and DeMichele model. The normalized cumulative frequency distributions of developmental period for each life stage were fitted to the three-parameter Weibull function. The attendance of shortened developmental times was apparent with $1_{st}-2_{nd}\;nymph,\;3_{rd}-4_{th}$ nymph, and total nymph stages in descending order. The coefficient of determination $r^2$ ranged between 0.80 and 0.87.

A Study of Various Filter Setups with FBP Reconstruction for Digital Breast Tomosynthesis (디지털 유방단층영상합성법의 FBP 알고리즘 적용을 위한 다양한 필터 조합에 대한 연구)

  • Lee, Haeng-Hwa;Kim, Ye-Seul;Lee, Youngjin;Choi, Sunghoon;Lee, Seungwan;Park, Hye-Suk;Kim, Hee-Joung;Choi, Jae-Gu;Choi, Young-Wook
    • Progress in Medical Physics
    • /
    • v.25 no.4
    • /
    • pp.271-280
    • /
    • 2014
  • Recently, digital breast tomosynthesis (DBT) has been investigated to overcome the limitation of conventional mammography for overlapping anatomical structures and high patient dose with cone-beam computed tomography (CBCT). However incomplete sampling due to limited angle leads to interference on the neighboring slices. Many studies have investigated to reduce artifacts such as interference. Moreover, appropriate filters for tomosynthesis have been researched to solve artifacts resulted from incomplete sampling. The primary purpose of this study is finding appropriate filter scheme with FBP reconstruction for DBT system to reduce artifacts. In this study, we investigated characteristics of various filter schemes with simulation and prototype digital breast tomosynthesis under same acquisition parameters and conditions. We evaluated artifacts and noise with profiles and COV (coefficinet of variation) to study characteristic of filter. As a result, the noise with parameter 0.25 of Spectral filter reduced by 10% in comparison to that with only Ramp-lak filter. Because unbalance of information reduced with decreasing B of Slice thickness filter, artifacts caused by incomplete sampling reduced. In conclusion, we confirmed basic characteristics of filter operations and improvement of image quality by appropriate filter scheme. The results of this study can be utilized as base in research and development of DBT system by providing information that is about noise and artifacts depend on various filter schemes.

Performance Status of Sanitary Management of School Food Service in the Jeonnam Area (전남지역 학교급식의 위생관리 실태)

  • 고무석;정난희;이전옥
    • Korean Journal of Human Ecology
    • /
    • v.7 no.1
    • /
    • pp.51-67
    • /
    • 2004
  • This study analyzed the effects of nutrition technicians' hygiene education on cooking workers' performance of hygiene management in order to ensure the security of school meals. The situation of cooking workers' disposition in subject schools was elementary school(51.1%) and middle school(48.9%) and the type of meals was rural area type(54.2%), urban type(36.5%). and island and isolated area type(9.3%). The methods of meals management were single cooking(88.2%) and joint cooking and management(11.8%). The type of distributing meals was distributing in a dining room(93.5%), in a classroom(3.7%), and in both dining room and classroom(2.8%). Nutrition technicians' employment form included regular(53.5%) and daily(88.2%). Their education was junior college graduate(50.2%), university graduate(44.8%). and graduate school students(5.0%). Cooking workers' employment form included daily(88.2%) and regular (11.1%). suggesting that most were regular. Most cooking workers(77.4%) had at least high school certificate. Regarding the situation of cooking workers' disposition in subject schools, the number of student per one cooking worker was found as 91-120(37.2%), 61-90(22.6%). 60 and under(21.l %). 121-15006.7%). and 151 and over(2.5%). Cooking workers' level of performance of hygiene management was post-working stage(66.37/75 marks), pre-working stage(64.22/75 marks). and working stage(20.34/25 marks), The counting of meals articles in a pre-working stage(20.34/25 marks). temperature and required time in a working stage(18.78/25 marks), and machinery equipment and hygiene in a pre-working stage(21.40/25 marks) showed lowest of performance, which suggest poor service of hygiene. Cooking workers' performance of hygiene management by working stage showed the significant difference with school class(p<.001), type of schools with meals(p<.05). state of cooking workers' employment(p<.001), and cooking worker's disposition(p<.05). A working stage showed the significant difference with type of schools with meals(p<.05). A post-working stage showed the significant difference according to type of schools with meals(p<.05), and the methods of meals management(p<.05), and cooking workers' disposition(p<.05). In the execution of hygiene education, individual hygiene was highest(94.8%), followed by the management of machinery equipment and tools(89.7%), food poisoning and microorganism(94.7%), and the method of food treatment(76.4%). A yearly plan of hygiene education included established(83.9%) and not established(l6.1%). Regular education included not executed(25.1%), 2-3 times a month(l6.1%), and more than 4 a month(4.0%) and occasional education was not executed(57.0%), 1-3 times a month(26.3%), and more than 4 a month(l5.7%). In the methods for hygiene education, oral education(95.7%) was used most, followed by demonstration(10.5%), poster/photo(10.5%), video/slide(3.7%), and computer(3.7%). Frequency of improvement and complement of hygiene education included once a month(56.3%), once a year(20.7%), by quarter(l1.5%), and every six months(1l.5%). Newspaper was used most in materials of hygiene education, followed by internet, TV, nutrition technician's reeducation, information exchange between members, educational office's training, and reference book, and educational office's material. and symposium. Cooking workers' assessment of the effect of hygiene education was conducted through observation(56.8%), check table(l5.2%), question(l4.0%), and examination(14.0%). The reason of cooking workers' low level of performance included habitual custom(53.9%), lack of understanding(20.4%), overwork(l4.6%), and lack of knowledge(l1.l%) and the reason of difficulty in hygiene education included lack of time(55.3%), lack of understanding(27.6%), lack of knowledge and information(8.7%), and lack of budget(48.0%).

  • PDF

A Study on the Dental Hygienists' Reactions to Noise When Occurred in Dental Clinic (치과병원에서 발생하는 소음에 대한 치과위생사의 반응)

  • Choi, Mi-Suk;Ji, Dong-Ha
    • Journal of dental hygiene science
    • /
    • v.9 no.4
    • /
    • pp.453-459
    • /
    • 2009
  • The purposes of this research were to evaluate the relationships of between characteristics of noise and annoyance of dental hygienist by noise in dental clinic. To investigate the dental clinic workers' reactions to noise when occurred in dental clinic, the noise level test in dental clinic and questionnaire were taken. As a result of noise evaluation, It shows that the range of noise level was 67.7~78.3dB(A) and frequency was very high (more than 4KHz). It's seem to be begins occurrence of stamina-loss, contraction of peripheral blood vessel, decrease of adrenocortical hormones. Most of respondents were affected by noise: 67% of respondents were nervous about noise and the rest of respondents were bearable. Analysis by NR-curve showed that it was exceed the noise permit level in working space. As a result of correlation - test, the more exposed dental hygienist to noise, the more felt the unpleasantness and fatigue. It's hard to sufficient explanation to patients about the dental treatment. So it's thoughts that insufficient explanation will negative impact on the patients' satisfaction and increase competitiveness in dental clinics. To remedy a unpleasantness and fatigue of noise in dental hygienist, it's considered that making an offer the ear protection and choosing the low noise-vib. equipment and using the masking effect. Therefore, It can be provide a pleasant working environment with dental hygienist and It will have a great advantage to dental clinics to improve their competitiveness.

  • PDF

Weight Control and Cardiovascular Risk in Middle-Aged Women (중년여성의 체중관리 실태와 성인병 위험도)

  • Kim, Jeong-Ah;Chaung, Seung-Kyo
    • The Korean Journal of Rehabilitation Nursing
    • /
    • v.7 no.1
    • /
    • pp.33-47
    • /
    • 2004
  • The purpose of this study was to investigate weight control practices and cardiovascular risk in middle-aged women. 304 middle-aged women were selected as subjects from thirties to fifthies living at J city in Chung-Buk Do. Data were collected using a questionnaire, anthropometric measurements, BP & total cholesterol level in serum from April 1, to June 30, 2003. The results of this study were as follows: The middle-aged woman's age is average $43.95{\pm}7.09yr$ and mean BMI(body mass index) was $23.54{\pm}3.09\;kg/m^2$. Underweight, normal weight, overweight, obese women were 3.0%, 39.5%, 27.9% and 29.6%respectively. Subjects perceived own as 'Slim' 5.9%, 'ordinary' 45.7%, 'Fat' 48.4%. Their weight perception coincide their own actual body weight but as many as 41.8% of overweight and 9.0% of obese perceived themselves as being 'ordinary'. Middle age women with past weight control experience were 55.6%, and only 35.5% was doing weight control at present. Of these subjects, 71.4% reported wanting to lose weight and the primary reason of weight control was to improve their appearance(39.53%). The most frequently reported weight control behavior was 'exercise' followed 'dieting', but 39.6% reported using 'diet food', 12.4% 'behavior modification', 12.4% 'fasting', and 'diet-drug'(3.6%) or 'smoking'(3.6%). Effective weight control methods were thought regular exercise(97.1%) & dieting (79.3%). And behavior modification(71.4%) or diet camp(60%) were effective, too. An average waist circumference was $79.80{\pm}9.47cm$, waist/hip ratio was $86.63{\pm}6.78$, waist/height ratio was $50.43{\pm}6.10$. In the index of abdominal obesity, 79.7 % of middle-aged women was waist/height ratio over 0.46, 65.3% was waist/hip ratio over 0.85, 28.4% was waist circumference over 85cm. There were significant differences in the degree of abdominal obesity according to age and BMI. In the index of cardiovascualr risk, 10.9% of middle aged women was systolic hypertension over 140mmHg, 18.7% was diastolic hypertension over 90mmHg and 10.6% was hypercholesterolemia over 200mg/dl. There was significant difference in systolic hypertension ratio according to age. There was significant difference in diastolic hypertension ratio according to age and obesity. There were significant differences in hypercholesterolemia accorting to obesity. The abdominal obesity indices and the levels of T-cholesterol in the serum, systolic and diastolic BP increased significantly according to age. T-cholesterol in serum was predicted 2.6% by waist/height ratio. And systolic BP was predicted 15.2% by waist/height, add BMI to 16.8%. Subject's diastolic BP was predicted 12.1% by BMI. Therefore waist/height ratio and BMI were significant factors for the predictors of cardiovascular risk. There was significant correlation between index of obesity and cardiovascular risk. T-cholesterol in serum had correlation with waist/eight ratio(r=0.174) and waist circumference(r=0.48). Systolic BP had correlation with waist/height ratio(r=0.387), and BMI(=0.371). diastolic BP correlation had correlation with BMI(r=0.343) and waist/height ratio(r=0.327). In conclusion, The prevalence of obesity was 29.6% in 304 cases, and increased as age after menopause increased. Middle-aged women's weight perception and actual BMI coincide but some of them did not. Trial to reduce weight was attempted. But most of them did not actually. Undesirable weight control method such as using drugs, fasting, smoking was used by some women. It is important to educate about health weight control methods and raise their awareness of exact body figures. High frequency of abdominal obesity in middle-aged women had correlation with hypertension and hypercholesterolemia. Abdominal index such as waist/height ratio, waist circumference, waist/hip ratio was used. Women's hypertension, hypercholesterolemia significantly related to body mass index and abdominal obesity.

  • PDF

The Effect of Chemical Composition and Sintering Temperature on The Improvement of Physical Properties of Mn-Zn Ferrites (Mn-Zn ferrite의 성분 및 소결 온도에 따른 물리적 특성의 향상 연구)

  • 고재귀
    • Journal of the Korean Magnetics Society
    • /
    • v.5 no.4
    • /
    • pp.269-274
    • /
    • 1995
  • The basic composition of Mn-Zn ferrite was $Mn_{0.631}Zn_{0.316}Fe_{2.053}O_{4}$(specimen A), $Mn_{0.584}Zn_{0.312}Fe_{2.104}O_{4}$(specimen B) and $Mn_{0.538}Zn_{0.308}Fe_{2.154}O_{4}$(specimen C) with additional 0.1 mol % $CaCo_{3}$ and 0.04 mol % $V_{2}O_{5}$. For high per¬meability and acceleration of grain growth, $CaCo_{3}$ and $V_{2}O_{5}$. was added. The mixture of the law materials was calcinated at $950^{\circ}C$ for 3 hours and then milled. The compacts of toroidal type were sintered at different temperature($1250^{\circ}C$, $1300^{\circ}C$, $1350^{\circ}C$) for 2 hours in $N_2$ atmosphere. The effects of the various raw material composition and sintered temperature on the physical properties of Mn-Zn ferrite have been investigated. They turned out to be spinel structure by X-ray diffraction and the size of grain from SEM was from $18\;\mu\textrm{m}\;to\;23\;\mu\textrm{m}$. As the sintering temperature was increased from $1250^{\circ}C$ to $1350^{\circ}C$, the initial permeability and magnetic induction has increased and the both of Q factor and coercive force has decreased. The coercive force and curie temperature were almost the same at each specimen Their values were about 0.45 Oe and $200^{\circ}C$. The frequency of specimen will used in the range from 200 kHz to 2 MHz. The basic composition of $Mn_{0.584}Zn_{0.312}Fe_{2.104}O_{4}$(specimen B) sintered at $1300^{\circ}C$ shows the best results at magnetic induction (Br & Bm).

  • PDF

A Prospective Study on Attitude of Professional Student toward Population Related Issues in Korea (대학전공별(大學專攻別) 전문직학생(專門職學生)들의 인구관련문제(人口關聯問題)에 대한 연차적(年次的) 변화(變化) 연구(硏究))

  • Lee, Kyung-Sik;Kim, Hwa-Joong
    • Journal of Preventive Medicine and Public Health
    • /
    • v.9 no.1
    • /
    • pp.11-24
    • /
    • 1976
  • This study was a part of large scale of a prospective study on attitudes of professional students in medicine, nursing and teaching toward population related issues in Korea. The study was first conducted in May 1974 and then in May 1975 for the 1974 class cohot using a questionaire consisted of attitude scales and other items developed by Lee. The purpose of stuay was twohold, namely, to determine the difference in students among specializations on one hand and between the first and second years in the 1974 class cohot regarding tile subject matter. A one-way analysis of variance was used for attitude scale, and absolute and relative frequency were computed for the analysis of non-attitude scale items by employing Fishers' Ratio and Duncan's multiple range test at 5% level and chi square test at 5% level as significance tests. The hypothesis 'students in health profession are more likely to have positive attitudes toward population related issues progressively as class year advances than students in teaching profession' was tested and the following results were obtained: 1) Nursing students were more likely to display favarable attitudes toward family planning than medical or teaching students although the class cohot showed slightly negative improvement in the second year. Medical and teaching students apperaed to have slightly improved attitudes in the second year. 2) Respondents in general perceived national family planning program as a means of population control and this tendency was more true among nursing students as the class year advances than two other professional groups of students. Students in teaching profession appeared to perceive it more as a means to improve individual family welfare while health students were likely to see as to improve maternal and child health. This tendency was progressively improved as the class year advanced. 3) The majority of students regardless of their respective specializations believed that family planning program should be directed toward the improvement of individual family welfare. No progressive changes in the class cohot were observed. 4) About the plan to use contraceptives in future, no singnificant differences were observes among different specializations nor in different class years. However, the majority was confirmed to have a plan to use contracepives in future. An increasing proportion of the undecided category was observed, as class year advanced among health students. 5) Students in health profession were found to be more favorable about 'more leisure opportunities' as motive for limiting number of children whereas education students indicated the reasons as 'facilitate ambitions' and 'economic base' The progressive changes toward positive direction in both groups were observed as the class years advanced. 6) Attitudes toward induced abortions of the health students were observed to be positively related to class years while an inverse relationship was found in teaching students who showed much less favor in the subject matter than health students. This phenomenon may be due to the different exposure to learning environments unique to respective specializations. 7) Health students were found to have more favorable attitudes toward population education in general than the teaching students. The teaching students appeared to have changed more to the negative direction when they became the second year while no such development was observed in health students. The teaching students seemed to hold a very conservative position with regard to sex education in schools. 8) About the equality of sexes, the nursing group was found to be most favorable while the reverse was true in the teaching group. A change in the negative direction as the class year advanced was found in the teaching group. 9) About questions related to fertility values-the 10 percent of respondents regardless of specialization indicated that they would maintain their single status in future, however no change was observed in the second year. The desired number of children was found to be two by the majority of students in nursing, medicine and teaching in order of high proportion. No changes in a different class year were observed. The childless marriage was seen by nursing students as a problem more than other students, but a slight change in positive direction was found when the nursing students became the second year. In summing, as data supported in the above, students in health profession demonstrated more favorable attitudes toward population related issues than the teaching students and this tendency became more apparent in the second year. It was noticed that health students were more conscious about the health aspect of population and family planning program while the teaching students gave more attention to the socioeconomic aspect. The sex variable seemed to have operated in the item related to the equality of sexes. In conclusion, as data presented in the above, the hypothesis of this study was accepted except in the few items. It should be noted that the limitation of this study is the short duration of the observation in measuring the possible attitude changes. It should include curriculum analysis for the respective specializations in order to indentify the area of curriculum impact on students in future study.

  • PDF