• Title/Summary/Keyword: System Frequency Response

Search Result 2,023, Processing Time 0.029 seconds

Catalog use study : with reference to universities in Daegu (대학도서관의 목록이용연구)

  • 최달현
    • Journal of Korean Library and Information Science Society
    • /
    • v.9
    • /
    • pp.241-266
    • /
    • 1982
  • This paper gives a summary and overview of a survey conducted at the catalogues of five universities in Daegu during November 1982. The major objective of this study was to secure information about user needs in order to improve the catalogue in Korean university libraries. Data was collected by a combined method of questionnaire and interview. A total of 379 respondents were taken on a randomly selected sample of catalogue users. Results of the survey can be summarized as follows: 1. Eighty-eight percent of the students answered that they had used the library more than twice a month. Nevertheless the number of students consulting the catalogue with the same frequency was only 220, or a n.0, pproximately 58 percent. Those who used the library most tended to use the catalogue more than those who rarely came to the library. 2. Those who had been shown how to use their own catalogue were only 32.5percent of which the students found the instruction sufficient for them to be able to use the catalogue were only 37.5 percent. In particular, they stated that instructions by printed materials and/or library orientation were so poor that they didn't give much help in using the catalogue. This problem makes many libraries to review their own method of instruction in order to encourage patrons to use the catalogue more effectively. 3. Most of the students consulted the catalogue in order to locate library materials. Known-item searches and subject searches were 84 and 16 percent respectively. While 70.5 percent of the students used the author-title catalogue without any difficulties, only 35.5 percent of those stated that using the classed catalogue was easy. 4. It was surprising that the number of students using title access in the search was far greater than that of students using author access. In contrast with this, other studies conducted by many earlier overseas investigators revealed that the great majority of patrons tended to use the latter first. Therefore, we should put more emphasis on the title entries in the catalogue itself as well as cataloging rules. 5. Most useful bibliographic elements in the entry were author, title, call number, date and publisher whereas edition, series statement and the location of publisher were rarely used compared with the other elements. Content note was the most desirable element in the entry to be involved, for many catalogers were used not to describe it on the note area. 6. The chief reason given for not using the catalogue was "I can manage without it" with "It's difficult to understand contents of the card entry." The other one was "It's useless to search materials by the catalogue because I've failed so many times to obtain them out of the stock." In response to this, circulation and acquisition system should be improved not to make such complaints any more.

  • PDF

A STUDY ON MENTAL HEALTH STATE OF HIGH SCHOOL STUDENTS (고등학생의 정신건강 상태에 관한 연구 -SCL-90을 이용, 서울시 인문계 1 . 3학년을 중심으로-)

  • 김은주
    • Korean Journal of Health Education and Promotion
    • /
    • v.5 no.2
    • /
    • pp.110-141
    • /
    • 1988
  • This study was conducted to find out the mental health state of high school students. First-year students and third-year students af liberal high schools is Seoul were subject to this study. Questionnaire of Symptom Checklist-90 and various factors was adopted for the survey. A total of 916 questionnaires was sellected for the analysis, and the results are obtained as follows; 1) The characteristics in responses to mental health scale showed that obsessive-compulsive scale score was the highest, followed by interpersonal-sensitivity, depression, hostility, and anxiety. The subject group of the students showed higher scores in nine symptom dimensions except somatization than other normal group. 2) Girl-students showed higher scores than boy-students in somatization, depression, and anxiety, whereas the opposite was true in hostility. 3) Third-year students got high scores, in somatization, anxiety and Depression. 4) Parental marriage state of the repondents showed significant differences in nine symptom dimensions of mental health. Scores of the students with parents was the lowest, followed by those of students with only mother, only father and the rest(no parents, divorced, sepaerated, step-parent) in increasing order. 5) Smoking students showed high score in obsessive-compulsive, depression, hostility, paranoid ideation, and psychoticism. Especially in hostility, they got much higher score. 6) Students with poor record at school got higher scores in every symptom dimension than those with good record at school, especially in obsessive-compulsive and depression scale. 7) Parents' attitude toward student showed significant effect on every scale. Students under over-expectation or indifference from parents were in bad mental health state. 8) Students who have advisor proved to be in better mental health state than those who never consult their personal problems with others. 9) He who has family history got higher scores in some scales. 10) Respondents who looked upon what they have learned in high school as being rather an obstacle to sound social life got high scores in all the symptom dimensions and next came those of the students who answered that there were a lot of unnecessary things in their learning. 11) Those for whom it would not quite necessary to enter college if there were little formal schooling discrimination in society got high scores in obsessive-compulsive, interpersonal sensitivity, depression, hostility, and in psychoticism, especially higher in obsessive-compulsive scale. 12) Mental health state of the students who are influenced by the social surroundings, mass media, and the home environments showed high score in 8 symptom dimensions. 13) Abnormal response frequency of this sample is as follows; 24.0% of boys, 23.8% of girls, 22.5% of the first-year students, and 26.9% of the third-year students. There were significant difference among the grades. 14) The factors of distinctive correlation between the dimensions of SCL-90 and 16 factors were the father's negative attitude and depression, negative responses on teaching contents and anxiety, and smoking and hostility. In conclusion, mental health state of liberal highschool students on the whole showed worse than other normal groups. It had close terms with relation with their parents, schoolwork, smoking, teaching contents, the social surrounding, mass media, and the home environments. Thus I believe there need not only mental health education of students, training of teachers, counceling of parents, but also changes in teaching contents, and the improvement of educational system and the social surroundings under the national support.

  • PDF

Comparison of Deterministic and Probabilistic Approaches through Cases of Exposure Assessment of Child Products (어린이용품 노출평가 연구에서의 결정론적 및 확률론적 방법론 사용실태 분석 및 고찰)

  • Jang, Bo Youn;Jeong, Da-In;Lee, Hunjoo
    • Journal of Environmental Health Sciences
    • /
    • v.43 no.3
    • /
    • pp.223-232
    • /
    • 2017
  • Objectives: In response to increased interest in the safety of children's products, a risk management system is being prepared through exposure assessment of hazardous chemicals. To estimate exposure levels, risk assessors are using deterministic and probabilistic approaches to statistical methodology and a commercialized Monte Carlo simulation based on tools (MCTool) to efficiently support calculation of the probability density functions. This study was conducted to analyze and discuss the usage patterns and problems associated with the results of these two approaches and MCTools used in the case of probabilistic approaches by reviewing research reports related to exposure assessment for children's products. Methods: We collected six research reports on exposure and risk assessment of children's products and summarized the deterministic results and corresponding underlying distributions for exposure dose and concentration results estimated through deterministic and probabilistic approaches. We focused on mechanisms and differences in the MCTools used for decision making with probabilistic distributions to validate the simulation adequacy in detail. Results: The estimation results of exposure dose and concentration from the deterministic approaches were 0.19-3.98 times higher than the results from the probabilistic approach. For the probabilistic approach, the use of lognormal, Student's T, and Weibull distributions had the highest frequency as underlying distributions of the input parameters. However, we could not examine the reasons for the selection of each distribution because of the absence of test-statistics. In addition, there were some cases estimating the discrete probability distribution model as the underlying distribution for continuous variables, such as weight. To find the cause of abnormal simulations, we applied two MCTools used for all reports and described the improper usage routes of MCTools. Conclusions: For transparent and realistic exposure assessment, it is necessary to 1) establish standardized guidelines for the proper use of the two statistical approaches, including notes by MCTool and 2) consider the development of a new software tool with proper configurations and features specialized for risk assessment. Such guidelines and software will make exposure assessment more user-friendly, consistent, and rapid in the future.

A RFID Tag Anti-Collision Algorithm Using 4-Bit Pattern Slot Allocation Method (4비트 패턴에 따른 슬롯 할당 기법을 이용한 RFID 태그 충돌 방지 알고리즘)

  • Kim, Young Back;Kim, Sung Soo;Chung, Kyung Ho;Ahn, Kwang Seon
    • Journal of Internet Computing and Services
    • /
    • v.14 no.4
    • /
    • pp.25-33
    • /
    • 2013
  • The procedure of the arbitration which is the tag collision is essential because the multiple tags response simultaneously in the same frequency to the request of the Reader. This procedure is known as Anti-collision and it is a key technology in the RFID system. In this paper, we propose the 4-Bit Pattern Slot Allocation(4-BPSA) algorithm for the high-speed identification of the multiple tags. The proposed algorithm is based on the tree algorithm using the time slot and identify the tag quickly and efficiently through accurate prediction using the a slot as a 4-bit pattern according to the slot allocation scheme. Through mathematical performance analysis, We proved that the 4-BPSA is an O(n) algorithm by analyzing the worst-case time complexity and the performance of the 4-BPSA is improved compared to existing algorithms. In addition, we verified that the 4-BPSA is performed the average 0.7 times the query per the Tag through MATLAB simulation experiments with performance evaluation of the algorithm and the 4-BPSA ensure stable performance regardless of the number of the tags.

A Study on the Management & Utilization of School Drinking Water (학교음용수 관리 및 이용실태)

  • Hong, Jung-Ha;Park, Young-Soo
    • The Journal of Korean Society for School & Community Health Education
    • /
    • v.1 no.2
    • /
    • pp.87-104
    • /
    • 2000
  • The purpose of this study was to obtain the basic data as a improvement method through the fact-revealing concerning the drinking water management of school and utilization of student. The problems of the research are as follows: First, to investigate status of management of drinking water by area and school. Second, to investigate student's utilization of drinking water by area and school. 1,400 students was selected at 45 elementary and middle-high schools located in Kang-won province, and this study was constituted of two questionnaires(for school's questionnaire and student's questionnaire). The results was analyse through the frequency analysis, $x^2$-test on the basis of the above research problem by SPSS program. The findings of this research are as follows; 1) The Management of School Drinking Water First, the source of school drinking water was mostly piped water. Inspection of water quality has been fulfilled under four times a year, in the other hands, from the result inspection, the schools which was given inadequate determination was 22.2%. Second, reservoir cleaning and hygiene inspection failed far short of the regulations. Especially, reservoir cleaning was managed by exterior consignment industry not low-level officials. Third, school water drinking was the most supplied through the type of water purifier. Water purifier has been distributed to city-located and middle-high school highly, factually the water from water purifier was served with water cup. Fourth, the selection standard of water drinking manager showed slightly differently by school, accordingly there need to develope integrated system with the respective to its effective systematic management. Fifth, water cup was mostly treated by only water clear, which is to vindicate the problems concerning hygiene management. 2) Utilization of school student on Drinking Water First, Disbelief on drinking water of school student was very high. Especially, proportion of middle-high school student's disbelief of drinking water was higher than elementary school student, also girls higher than boys. Many of student have heard to don't drink water from around people. And there were showed meaningful differences by area and school. Second, It was showed many student recognize had to utilize water purifier, boiled water. However, they have still drunken the tap water or portable water from their home. Third, Many of student showed negative response with the respective to the management conditions of drinking water in classroom, There were showed meaningful differences by area and school. From the fact-revealing of water cup management, Students mostly answered to 'only water clear' and the answer of 'None use' or 'With personal cup' was higher. Fourth, In bad experience of Drinking Water, student mostly answered to 'occasionally' and there were showed meaningful differences by school. student's disease experience with school drinking water was few and there were showed meaningful differences by area and gender.

  • PDF

A Study on Buffeting Responses of a In-service Steel Cable-stayed Bridge Using Full-scale Measurements (실측 데이터를 이용한 공용중인 강사장교의 버페팅 응답 분석)

  • Lee, Deok Keun;Kong, Min Joon;You, Dong Woo
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.36 no.3
    • /
    • pp.349-359
    • /
    • 2016
  • In order to analytically evaluate buffeting responses, the analysis of wind characteristics such as turbulence intensity, turbulence length, gust, roughness coefficient, etc must be a priority. Static aerodynamic force coefficients, flutter coefficients, structural damping ratios, aerodynamic damping ratios and natural frequencies affect the analytical responses. The bridge interested in this paper has being been used for 32 years. As the time passes, current terrain conditions around the bridge are different markedly from the conditions it was built 32 years ago. Also, wind environments were considerably varied by the climate change. For this reason, it is necessary to evaluate the turbulence intensity, length, spectrum and roughness coefficient of the bridge site from full-scale measurements using the structural health monitoring system. The evaluation results indicate that wind characteristics of bridge site is analogous to that of open terrain although the bridge is located on the coastal area. To calculate buffeting responses, the analysis variables such as damping ratios, static aerodynamic force coefficients and natural frequency were evaluated from measured data. The analysis was performed with regard to 4 cases. The evaluated variables from measured data are applied to the first and second analysis cases. And the other analysis cases were performed based on Design Guidelines for Steel Cable Supported Bridges. The calculated responses of each analysis cases are compared with the buffeting response measured at less than 25m/s wind speed. It is verified that the responses by the numerical analysis applying the estimated variables based on full-scale measurements are well agreed with the measured actual buffeting responses under wind speed 25m/s. Also, the extreme wind speed corresponding to a recurrence interval 200 years is derived from Gumbel distribution. The derived wind speed for return period of 200 years is 45m/s. Therefore the buffeting responses at wind speed 45m/s is determined by the analysis applying the estimated variables.

Preparation and Electrochemical Characteristics of Polymer Electrolyte Based on MCM-41/Poly(ethylene oxide) Composites (MCM-41/Po1y(ethylene oxide) 복합체로 구성된 고분자 전해질의 제조와 전기화학적 특성)

  • Kim Seok;Kang Jin-Young;Lee Sung-Goo;Lee Jae-Rook;Park Soo-Jin
    • Polymer(Korea)
    • /
    • v.29 no.4
    • /
    • pp.403-407
    • /
    • 2005
  • In this work, the solid polymer electrolyte (SPE) composites, which are composed of poly(ethylene oxide) (PEO), mesoporous mobil crystalline material-41 (MCM-41), and lithium salt, are prepared in order to investigate the influence of MCM-41 contents on the ionic conductivity of the composites. The crystallinity of the SPE composites was evaluated using differential scanning calorimeter (DSC) and X-ray diffraction (XRD). The ionic conductivity of the SPE composites was measured by the frequency response analyzer (FRA). As a result, the addition of MCM-41 into the polymeric mixture prohibited the growth of PEO crystalline domain due to the mesoporous structures of the MCM-41. The $P(EO)_{16}LiClO_4$/MCM-41 electrolytes show an increased ion conductivity as a function of MCM-41 content up to 8 $wt\%$ and a slightly decreased conductivity over 8 $wt\%$. These ion conductivity characteristics are dependent on a change of polymer crystallinity in the presence of MCM-41 system.

Factors Influencing Efficient Agrobacterium-mediated Transformation of Panicum spp. (Agrobacterium법에 의한 Panicum속 식물들의 효과적인 형질전환에 영향을 미치는 요인)

  • Seo, Mi-Suk;Takahara, Manabu;Takamizo, Tadashi
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.31 no.1
    • /
    • pp.1-8
    • /
    • 2011
  • Molecular techniques such as genetic transformation are powerful tools that can be used for the genetic modification of warm-season grasses. The P. meyerianum with high regeneration ability was used for establishing an Agrobacterium-mediated transformation system. We investigated various factors affecting Agrobacterium infection by examining GUS gene expression of pCAMBIA1304 vector. Among various concentration of acetosyringone and betaine tested for inoculation and co-cultivation, 10 mg/L acetosyringone and 60 mg/L betaine resulted in the highest transformation frequency in terms of GUS expression. The calli of 4 species of Panicum spp. with excellent tissue culture response were inoculated with Agrobacterium under the optimal infection conditions. The high activity of GUS gene was observed in all species and hygromycin-resistant calli expressing GFP were obtained in P. meyerianum, P. longijubatum, P. stapfianum and guineagrass Noh-PL1. Co-cultivated calli were transferred onto the selection medium containing hygromycin, and the hygromycin resistant calli were selected after 3 months. Hygromycin-resistant plantlets were then successfully regenerated from the calli and grown in a greenhouse. We confirmed stable insertion of hpt gene among the hygromycin-resistant plantlets of P. meyerianum by PCR analysis.

Research on Sex Education of Young Children's Mothers (유아 어머니의 자녀 성교육 실천정도)

  • Guem, Sun-Hee;Kim, Myung-Hee;Kang, In-Soon
    • Korean Parent-Child Health Journal
    • /
    • v.8 no.1
    • /
    • pp.49-63
    • /
    • 2005
  • Purpose: The present study is a descriptive research on the content of sex education conducted at home by the mothers of young children who are attending five kindergartens located in Busan, Korea. This study aims to provide basic materials for systematic sex education at home and in the school. Method: Based on the literature review and prior researches, the writer made a questionnaire consisting of 30 items regarding necessities, contents and difficulties of sex education. The 307 questionnaires were collected out of 480 which were distributed by the kindergarten teachers. Data was analysed with frequency and percentage using the SPSS Win 10.0 Program. The main subjects of the study were mothers in their thirties, who understood the necessity of sex education. However, they were lack of enough sexual knowledge in accordance with the transforming sexual culture and lack of suitable materials. They did not plan to educate their children according to their developmental stages, but just taught them verbally rather than using common materials for the situation. Result Regarding the origin of life that children often asks, mothers did not give a scientific and correct response to satisfy their curiosity about sex, saying that a baby was created after marrying a loved one. While more mothers than the prior research responded correctly to the queries of the path of delivery, some mothers did not. It may cause some children to suppress the questions, which may result a distorted sexual knowledge. That is because mothers understood that sex education was to deliver sexual knowledge, but not realized that sex education was a human education carried out throughout life. Mothers fell short of sexual knowledge, capability, and confidence, comparing with swift social changes and children's capacity. As a result, it is necessary to inspire sexual awareness into mothers and educate them through training. It is also needed to secure a training program similar to a teacher training program. Conclusion: It is essential to develop and to provide evaluation tools as well as proper materials in accordance with the children's developmental stage, so that organic management system among home, education institute and society must lead sex education Further, it is necessary to provide teaching methods and materials to mothers regularly, so that the school and home may conduct sex education together to cope with difficulties.

  • PDF

Exposure to Dithiopyr Alters Swimming Performance Parameters in Zebrafish (Dithiopyr에 노출이 zebrafish의 유영 행동에 미치는 영향)

  • Oh, Junyoung;Park, Eun-Jin;Kang, Seongeun;Lee, Seungheon
    • Journal of Life Science
    • /
    • v.26 no.2
    • /
    • pp.181-189
    • /
    • 2016
  • The aim of this study was to identify the effects of dithiopyr (DTP), a herbicide, on behavior in zebrafish. The toxicity of DTP has rarely been investigated in fish. In the present study, zebrafish were exposed to different concentrations of DTP in the range of 10-20 μM for 48 h in a test container, in order to measure the value of median lethal concentrations (LC50). Behavioral experiments were performed, including the novel tank test (NTT) and the open field test (OFT), to assess stress responses or locomotion. After exposure to the DTP solution at a sublethal concentration of 2.5–10 μM for 6 min, the behavior of the zebrafish was observed for 6 min. In the acute toxicity test, the LC50 value of DTP showed as 14.49 μM in the zebrafish. The NTT showed that the duration of immobility and the velocity were significantly increased by exposure at a concentration of 5 μM of DTP, compared with a control group (p<0.05). However, compared with the control group, DTP significantly decreased the distance moved and the frequency at the top of the tank, and significantly increased the turn angle and duration at the bottom, in a concentration-dependent manner (p<0.05). In addition, in the OFT, exposure to DTP significantly decreased the distance moved and velocity compared with the control group (p<0.05). Exposure to DTP also significantly increased the duration of immobility, the turn angle, and the meandering movement, in a concentration-dependent manner (p<0.05). Further, exposure to DTP at a low concentration elevated whole-body cortisol levels in the zebrafish. The results of this study thus suggest that DTP induces a toxic response and negative effects on behavior and the endocrine system in zebrafish.