• Title/Summary/Keyword: higher order elements

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A study on the improvement of shape design sensitivity in eigenvalue problems using semi-analytical method (반해석적 방법을 이용한 고유치 문제의 형상 설계 민감도 향상에 관한 연구)

  • 김현기;조맹효
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2001.10a
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    • pp.159-166
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    • 2001
  • Structural optimization often requires the evaluation of design sensitivities. The Semi Aanalytic method(SAM) for computing sensitivity is popular in shape optimization because this method has several advantages. But when relatively large rigid body motions are identified for individual elements, the SA method shows severe inaccuracy. In this paper, the improvement of design sensitivities corresponding to the rigid body mode is evaluated by exact differentiation of the rigid body modes. Moreover, the error of the SA method caused by numerical difference scheme is alleviated by using a series approximation for the sensitivity derivatives and considering the higher order terms. Finally, this paper shows that the refined SA method including the iterative method improves the results of sensitivity analysis in dynamic problems.

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The Use of Hermite Cubic Element for Inviscid Convective Equations (비점성 대류 방정식의 계산을 위한 Hermite 3차 요소의 사용에 대한)

  • 김진환
    • Journal of Ocean Engineering and Technology
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    • v.7 no.1
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    • pp.99-106
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    • 1993
  • The use of Hermite cubic element, as a possible finite element computation of transport equations containing shocks, has been invesigated. In the present paper the hermite cubic elements are applied to both linear and nonlinear scalar one and two dimensional equations. In the one dimensional problems, numerical results by the hermite cubic element show better than those by the linear element, and the steady state solution by the hermite cubic element yields result with good resolution. This fact proves the superiority of the hermite cubic element in space differencing. In two dimensional case, the results by the hermite cubic element shows a boundary instability, and the use of higher order time differencing method may be necessary for fixing the problem.

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Wavelet Packet Image Coder for Digital Contents Using Coefficients Partition Scan Order (계수분할을 이용한 디지털 컨텐츠의 웨이블릿 패킷 영상압축)

  • 한수영;이두수
    • Journal of the Korea Society of Computer and Information
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    • v.8 no.3
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    • pp.47-52
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    • 2003
  • In this paper. a new wavelet packet image coder is proposed for images that include many high-frequency components using the relation between subbands. The new algorithm presents parent-child relationship for reducing image reconstruction error using relations between individual frequency subbands. By parent-child relationship, every coefficient is partitioned and encoded for the zerotree structure. It demonstrates higher PSNR under the same bit rate. These results show that the encoding process of the proposed coder is more accurate than the conventional ones for images that include many high-frequency elements.

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Comparative analysis of nursing students' reflection levels before and after debriefing in simulation training in South Korea: qualitative analysis design

  • Sun-Young Lim;Mi-Jeong Bae
    • Child Health Nursing Research
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    • v.30 no.3
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    • pp.167-175
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    • 2024
  • Purpose: To measure the level of reflection, this study analyzes diaries written by third-year nursing students before and after the debriefing stage in simulation training. A qualitative study using diary entries from 15 nursing students to explore reflection depth. Methods: Students engaged in simulation training and the debriefing stage, documenting their reflections in diaries. Before and after debriefing, reflections were rated from Level 1 (reflectivity) to Level 7 (theoretical reflectivity). Results: The total number of reflection levels rose significantly from 545 to 829 post-debriefing, enhancing higher-order reflection. The shift signifies a move from superficial to deep reflection, highlighting debriefing's role in fostering critical thinking. Conclusion: The findings underscore the critical role of debriefing in enhancing reflective thinking in nursing education. There is a demonstrated need for further research into the specific elements of debriefing that are most effective at promoting deep reflection. Future studies should conduct comparative analyses of different debriefing methods and approaches across various educational settings. This research could lay the foundation for designing more effective debriefing strategies that foster critical thinking and improve learning outcomes in nursing education.

The Study on the High Nocturnal Concentration of Ground Level Ozone (야간 지표 고농도 오존에 관한 연구)

  • 김유근;홍정혜
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.6
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    • pp.545-554
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    • 1998
  • The diurnal variation of O3 concentration shows two peaks, the first peak at noontime and the secondary peak at night. In order to show why the secondary peak, high nocturnal O3 concentration, occurs without sunlight which is a essential factor of a photochemical response, the O3 concentration, several weather elements and synoptic weather map were used for June∼September at 1995, 1996. The mean concentration of high nocturnal O3 concentration days is higher by 5.4 ppb than that of low nocturnal O3 concentration days. The nocturnal O3 concentration is higher than that of diurnal O3 concentration during high nocturnal O3 concentration days, at July, 1995 and June, 1996. The high nocturnal O3 concentration is related to low air pressure, high cloud cover and high wind speed. The correlation coefficient, r. between nocturnal O3 concentration and wind speed, pressure and cloud cover is 0.387, -0.218, and 0.194, respeftiviely. It is interesting that the O3 concentration increases at Pusan when the typhoon passes by. The same result showed at Taegu when the typhoon FAYE passed by. According to the analysis of nocturnal O3 concentration for June∼September at 1995 and 1996, it seems that the high nocturnal O3 concentration relates to the trough and cyclones passing by Pusan.

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Dynamic Behaviors of Skewed Bridge with PSC Girders Wrapped by Steel Plate

  • Rhee, In-Kyu;Kim, Lee-Hyeon;Kim, Hyun-Min;Lee, Joo-Beom
    • International Journal of Railway
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    • v.3 no.3
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    • pp.83-89
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    • 2010
  • This paper attempts to extract the fundamental dynamic properties, i.e. natural frequencies, damping ratios of the 48 m-long, $20^{\circ}$ skewed real bridge with PSC girders wrapped by a steel plate. The forced vibration test is achieved by mounting 12 Hz-capacity of artificial oscillator on the top of bridge deck. The acceleration histories at the 9 different locations of deck surface are recorded using accelerometors. From this full-scaled vibration test, the two possible resonance frequencies are detected at 2.38 Hz and 9.86 Hz of the skewed bridge deck by sweeping a beating frequency up to 12 Hz. The absolute acceleration/energy exhibits much higher in case of higher-order twist mode, 9.86 Hz due to the skewness of bridge deck which leads asymmetric situation of vibration. This implies the test bridge is under swinging vertically in fundamental flexure mode while the bridge is also flickered up and down laterally at 9.86 Hz. This is probably by asymmetric geometry of skewed deck. A detailed 3D beam-shell bridge models using finite elements are performed under a series of train loads for modal dynamic analyses. Thereby, the effect of skewness is examined to clarify the lateral flickering caused by asymmetrical geometry of bridge deck.

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Chemical properties of Watercress(Oenanthe javanica D.C.) Depend upon Cultivating Methods (재배방법이 다른 미나리의 성분 특성)

  • Lee, Hong-Yeol;Yoo, Maeng-Ja;Chung, Hee-Jong
    • Journal of the Korean Society of Food Culture
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    • v.16 no.3
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    • pp.235-242
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    • 2001
  • Chemical properties of the different parts of watercress(Oenanthe javanica D.C.) grown and harvested from the culture fields under different cultivating methods were studied. In proximate analyses of watercress in parts, moisture contained more in stem than in root or in leaf, but crude protein and crude lipid contents were lower in stem than in root or in leaf. Crude ash in root contained up to about double amount in leaf or stem. Major mineral elements detected in watercress were Fe, Mg, Ca, and K, and their contents in root was higher than those in stem or leaf. Especially, Fe in root was significantly higher than that in stem or in leaf. Total free sugar composed mainly with fructose and glucose, was the highest in watercress from Hwasoon and followed the watercress from Jeonju and Donggok in order. Free sugar content was highest in leaf and the lowest in root. Major water-soluble vitamins were vitamin C, thiamin and biotin and the content of vitamin C was higher than others. These vitamins contained more in leaf than in stem or root. Niacin contained 6.09 mg/100 g in leaf of watercress from Hwasoon, which was much higher than others, but it was not detected in stem of watercress from Jeonju. Organic acids detected were oxalic acid, citric acid and malic acid and other 12 organic acids were not detected. In fatty acid composition, there were significant differences among watercresses from different parts and different culture fields. Linoleic acid, linolenic acid and palmitic acid were major fatty acids contained in watercress and it took about 80% of the total content. Amino acid content in leaf was higher than that in root and in stem. Glutamic acid and proline were major amino acids in stem of watercress from Jeonju and in stem of watercresses from Hwasoon and Donggok, respectively. In leaves of all three watercresses glutamic acid content was the highest.

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A study on the job analysis of dental hygienist in Gwangju (광주광역시 치과위생사의 직무분석에 관한 조사 연구)

  • Ha, Myung-Ok;Youn, Hye-Jeong
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.5
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    • pp.807-817
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    • 2010
  • Objectives : The purpose of this study was to analyzes the job implementation of dental hygienist at dental hospital(university), dental clinic and general hospital in the city of Gwangju. Methods : The subjects in this study were dental hygienists who worked at dental hospital(university), dental clinic and general hospital in the city of Gwangju. A survey was conducted by post from June 10 to August 10. Out of the collected data, 204 answer sheets were analyzed. Results : 1. 'Medical & Dental history taking', 'Extra & Intra oral examination' and 'Dental hygiene care plane' in dental clinic were significantly higher than dental hospital(university) and general hospital(p<0.001). 'Remove of extrinsic stain' and 'Treatment of hypersensitivity tooth' in dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.001). 'Preventive dental caries treatment' and 'Diet control' were shown the low frequency of job implementation. 2. Almost task elements of dental assistance duty shown that dental hygienists under the 24 years old were significantly higher dental hygienists over the 30 years old(p<0.05) and dental clinic and general hospital were significantly higher than dental hospital(university)(p<0.05) in frequency of job implementation. 3. 'Dental staff supervision', 'Patient management' and 'Dental chart arrangement' shown that dental hygienists over the 30 years old were significantly higher than dental hygienists under the 24 years old in frequency of job implementation(p<0.05). 'Infection control' of dental hygienists over 30 years old was significantly lower than dental hygienists under the 24 years old(p<0.001). Conclusions : The results of this study indicate that a scope of dental hygienists' job need to extend also in order to accomplish a job efficiently, is suggested that the effort is necessary to improve a quality of dental hygienist and to change of recognition of the dentist about dental hygienists' job.

A Study on Reform Case of the Citizen Service Delivery System by using IT : Focused on the Implementation of Public Utility Charges Depreciation Simplification and its Implications (정보기술을 활용한 주민서비스 전달체계 개선사례 연구 : "공공요금 감면절차 간소화" 구현 및 성공요인 중심)

  • Kim, Wan Pyong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.6 no.3
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    • pp.221-230
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    • 2010
  • Citizens' demand, which has been previously focused on welfare, is now expanding to include elements for higher quality of life such as employment, housing, culture, and sports. Accordingly, the government, with an aim of effectively delivering resident services that satisfy various demands, is committed to transforming the central government-oriented service system into the integrated service system based on public-private partnership. The government is also dedicated to expanding services to 8 areas including not only welfare but also healthcare, employment, housing, education, sports, culture, and tourism, which are directly related to everyday lives of residents. This project is designed to support such reforms in the citizen service delivery system in order to enhance quality of life of local residents. This study is to draw implications from analysis for implementing the citizen service integrated information system in order to reform the citizen service delivery system effectively through examinations and analyses of citizen services provided by the central government. Especially focus on public utility charges depreciation simplification citizen service. Its implications are expected to offer a real contribution for central and local Governments that want to increase the productivity of implementing eGovernment service.

A Study on the Actual Condition of Drug Abuse by Some Juveniles in Seoul - Based on Third School Year Students of Some Senior High Schools - (서울 시내 일부 청소년의 약물남용 실태에 관한 조사 연구 - 고등학교 3학년 학생을 중심으로 -)

  • Koh, Hong-Kyeong;Kim, Myung
    • Korean Journal of Health Education and Promotion
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    • v.7 no.1
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    • pp.72-82
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    • 1990
  • The actual condition of drug abuse by some Juveniles in our country and effects of some elements on their drug abusing were observed providing basic materials for health education to juveniles to contribute to the health improvement of them and the reduction of the harmfulness of drug abuse. 1035 third school year students of some senior high schools in Seoul were subjected to the questionnaire survey. The results could be summarized as follows : 1. Among the twelve kinds of drug involved in the study, alcohol (72.0%), cigarette (44.2%), stimulants (23.9%), analgesics (7.9%) appeard abused in the order named. 2. As for the motives of using antitussives, 30.1% of students answered because of curiosity, then 28.8%, in order to get a calm condition, and then 16.4%, to get along with friends. 3. As the result from seeing how much each drug abuser is contact with his family, frends, school, social surroundings and himself, every abuser appeared having higher degree of discontentment with family, school, society and himself excepting friends. 4. And when analyzed the relationship between their misconducting and drug-abusing, a close relationship was shown : mere abusers among misconduct-experienced students, and more misconduct-experienced students among abusers.

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