• Title/Summary/Keyword: Movement data

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19th-Century Morality Dispute in Context of History of Thought - From Four-Seven Dispute to Morality Dispute (사상사(思想史)의 맥락에서 본 19세기 심설논쟁(心說論爭) - 사칠논쟁(四七論爭)에서 심설논쟁(心說論爭)까지 -)

  • Choi, Young-sung
    • The Journal of Korean Philosophical History
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    • no.59
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    • pp.9-38
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    • 2018
  • Joseon Neo-Confucianism had important disputes throughout its hundred years of history. Starting in mid-16th century, Four-Seven Dispute focused on 'Qing (情, emotion)' while Horak Dispute that emerged in early 18th century put emphasis on whether people and things have the same 'Xing (性, nature).' These two disputes lasted until late Joseon. In that process, their issues were clearly recognized and consequently, characteristics of Joseon Neo-Confucianism were well demonstrated. With Western power surging in since mid-18th century, Joseon Neo-Confucianism should develop logic to cope with the Western power. One of responding logics was Zhulilun (主理論, theory of reason) in Neo-Confucianism. Diverse discussions particularly on 'Xin (心, mind)' were expansively made. From the notion of Xin Tong Xing Qing (心統性情) that Xin converges with Xing and Qing, an argument that Xin should be seen as 'Li (理, reason)' and another that Xin is basically 'Qi (氣, force of nature)' were up against each other. The academia heated up with issues raised such as whether Xin and Mingde (明德, bright virtue) are the same notion and whether Mingde should be seen as 'Li' or 'Qi', etc. Defining morality dispute in the late Joseon along with Four-Seven Dispute and Horak Dispute as 'three major disputes in Joseon Neo-Confucianism,' this paper focuses on clarifying their status, actuality and significance. Morality dispute was not only a theoretical dispute. It has significance in the aspect of 'topicality.' It directly and indirectly affected movements against Western and Japanese power, loyal troop's activities and independence movement as well. Compared to Four-Seven Dispute and Horak Dispute, morality dispute is more complex and expansive. In addition, it requires systematic organization of data. Intercomparison of three major disputes is one of key topics to determine characteristics of Joseon Neo-Confucianism.

International and domestic research trends in longitudinal connectivity evaluations of aquatic ecosystems, and the applicability analysis of fish-based models (수생태계 종적 연결성 평가를 위한 국내외 연구 현황 및 어류기반 종적 연속성 평가모델 적용성 분석)

  • Kim, Ji Yoon;Kim, Jai-Gu;Bae, Dae-Yeul;Kim, Hye-Jin;Kim, Jeong-Eun;Lee, Ho-Seong;Lim, Jun-Young;An, Kwang-Guk
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.634-649
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    • 2020
  • Recently, stream longitudinal connectivity has been a topic of investigation due to the frequent disconnections and the impact of aquatic ecosystems caused by the construction of small and medium-sized weirs and various artificial structures (fishways) directly influencing the stream ecosystem health. In this study, the international and domestic research trends of the longitudinal connectivity in aquatic ecosystems were evaluated and the applicability of fish-based longitudinal connectivity models used in developed countries was analyzed. For these purposes, we analyzed the current status of research on longitudinal connectivity and structural problems, fish monitoring methodology, monitoring approaches, longitudinal disconnectivity of fish movement, and biodiversity. In addition, we analyzed the current status and some technical limitations of physical habitat suitability evaluation, ecology-based water flow, eco-hydrological modeling for fish habitat connectivity, and the s/w program development for agent-based model. Numerous references, data, and various reports were examined to identify worldwide longitudinal stream connectivity evaluation models in European and non-European countries. The international approaches to longitudinal connectivity evaluations were categorized into five phases including 1) an approach integrating fish community and artificial structure surveys (two types input variables), 2) field monitoring approaches, 3) a stream geomorphological approach, 4) an artificial structure-based DB analytical approach, and 5) other approaches. the overall evaluation of survey methodologies and applicability for longitudinal stream connectivity suggested that the ICE model (Information sur la Continuite Ecologique) and the ICF model (Index de Connectivitat Fluvial), widely used in European countries, were appropriate for the application of longitudinal connectivity evaluations in Korean streams.

Exploring the Ways to Use Maker Education in School (학교 교육 활용을 위한 메이커 교육 구성 요소 탐색)

  • Kwon, Yoojin;Lee, Youngtae;Lim, Yunjin;Park, Youngsu;Lee, Eunkyung;Park, Seongseog
    • Journal of Korean Home Economics Education Association
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    • v.32 no.4
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    • pp.19-30
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    • 2020
  • Maker education started on the basis of the maker movement in which makers gathered in makerspace share their activities and experiences, and the educational value pursued in maker education is based on the constructivist paradigm. The purpose of this study is to present maker education components to be used in school education, focus on the characteristics and educational values of maker education, and explore ways to use them. To this end, this study explored the theoretical grounds to re-conceptualize maker education, drew statements based on in-depth interview data of teachers conducting maker education classes, and reviewed its validity through experts. Based on these statements, by deriving the components for the use of maker education, the direction of maker education in school education was set, and an example framework that could be used in subject class and creative experiential learning was proposed. Research shows that in maker education, makers cooperate to carry out activities, share ideas with others and try to improve them, and include self-direction such as learning, tinkering, design thinking, sharing and reflection. can see. In addition, maker education emphasizes experiential learning that can solve real problems that students face, rather than confining specific activities to student choices as needed. It emphasizes the learner's course of action rather than the outcome of the activity, tolerates the learner's failure, and emphasizes the role of the teacher as a facilitator to promote re-challenge. In the future, it can be used in various ways in each subject (curriculum expert, teaching/learning expert, elementary and middle school teachers, parents, local educators, etc.) and school activities, and it will contribute to setting future research directions as a basic research for school maker education.

Composition of Curriculums and Textbooks for Speed-Related Units in Elementary School (초등학교에서 속력 관련 단원의 교육과정 및 교과서 내용 구성에 관한 논의)

  • Jhun, Youngseok
    • Journal of Korean Elementary Science Education
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    • v.41 no.4
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    • pp.658-672
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    • 2022
  • The unique teaching and learning difficulties of speed-related units in elementary school science are mainly due to the student's lack of mathematical thinking ability and procedural knowledge on speed measurement, and curriculums and textbooks must be constructed with these in mind. To identify the implications of composing a new science curriculum and relevant textbooks, this study reviewed the structure and contents of the speed-related units of three curriculums from the 2007 revised curriculum to the 2015 revised curriculum and the resulting textbooks and examined their relevance in light of the literature. Results showed that the current content carries the risk of making students calculate only the speed of an object through a mechanical algorithm by memorization rather than grasp the multifaceted relation between traveled distance, duration time, and speed. Findings also highlighted the need to reorganize the curriculum and textbooks to offer students the opportunity to learn the meaning of speed step-by-step by visualizing materials such as double number lines and dealing with simple numbers that are easy to calculate and understand intuitively. In addition, this paper discussed the urgency of improving inquiry performance such as process skills by observing and measuring an actual object's movement, displaying it as a graph, and interpreting it rather than conducting data interpretation through investigation. Lastly, although the current curriculum and textbooks emphasize the connection with daily life in their application aspects, they also deal with dynamics-related content somewhat differently from kinematics, which is the main learning content of the unit. Hence, it is necessary to reorganize the contents focusing on cases related to speed so that students can grasp the concept of speed and use it in their everyday lives. With regard to the new curriculum and textbooks, this study proposes that students be provided the opportunity to systematically and deeply study core topics rather than exclude content that is difficult to learn and challenging to teach so that students realize the value of science and enjoy learning it.

The Trend of Cigarette Design and Tobacco Flavor System Development

  • Wu, Jimmy Z.
    • Journal of the Korean Society of Tobacco Science
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    • v.24 no.1
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    • pp.67-73
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    • 2002
  • In light of addressing consumer health concern, coping with anti-tobacco movement, and promoting new product, tobacco industry is actively pursuing to make a new generation of cigarettes with low tar and nicotine deliveries, and less harmful substances. Low tar and low nicotine cigarettes increases their market shares dramatically world wide, especially in KT&G, multinational tobacco companies, EU countries, even in China regulated by CNTC to set up yearly target to lower tar and nicotine deliveries. On the other hand, to design a new cigarette with reduced harmful substances begins to gain speed. The "modified Hoffmann list" publishes thirty plus substances in tobacco leaf and main smoke stream, which is the prime suspect causing health problems. Various ways and means are developed to reduce such components including new tobacco breeds, new curing method, tobacco leaf treatment before processing, selected filtration system, innovated casing system to reduce free radicals, as well as some non conventional cigarette products. In TSRC held this year, the main topic is related to reduce tobacco specific nitrosamines in tobacco leaf. The new generation of cigarette is in the horizon. It still needs a lot help to produce commercial products with satisfied taste and aroma characters. The flavor industry is not regulated by many governments demanding which ingredients might or might not be for tobacco use. However, most of the cigarette companies self impose a list of ingredients to guide flavor suppliers to design flavors. Unfortunately, the number of ingredients in those lists is getting shorter every year. It is understandable that the health is not the only reason. Some cigarette companies are playing safe to protect the company from potential lawsuit, while others are just copying from their competitors. Moreover, it is obvious that it needs more assistance from casings and flavors to design new generation of cigarettes with missing certain flavor components in tobacco leaf and main smoke stream. These flavor components are either non-existed or at lower level at new form of cured tobacco leaf or filtered in the main smoke stream along with reduced harmful substances. The use of carbon filters and other selected filtration system poses another tough task for flavor system design. Specific flavor components are missing from the smoke analysis data, which brings a notion of "carbon taste" and "dryness" of mouth feel. It is ever more demanded by cigarette industry to flavor suppliers to produce flavors as body enhancer, tobacco notes, salivating agents, harshness reducer, and various of aromatic notes provided they are safe to use. Another trend is that water based flavor or flavor with reduced ethanol as solvent is gaining popularity. It is preferred by some cigarette companies that the flavor is compounded with all natural ingredients or all ingredients should he GMO free. The new generation of cigarettes demands many ways of new thinking process. It is also vital for tobacco industry. It reflects the real needs for the consumers that the cigarette product should be safe to use as well as bearing the taste and aroma characters smokers always enjoyed. An effective tobacco flavor system is definitely a part of the equation. The global trend of tobacco industry is like trends of any other industries lead by consumer needs, benefited with new technology availability, affected by the global economy, and subjected for various rules and regulations. Anti-tobacco organizations and media exceptionally scrutinize cigarette, as a legal commercial product. Cigarette is probably the most studied commercial product for its composition, structure, deliveries, effects, as well as its new developmental trend. Therefore, any new trend of cigarette development would be within these boundaries. This paper is trying to point out what it would be like for tobacco industry in the next few yews and what concerns the tobacco industry. It focuses mostly on the efforts to produce safer cigarettes. It is such a vital task for the tobacco industry and its affiliate industries such as cigarette papers, filters, flavors, and other materials. The facts and knowledge presented in this paper might be well known for the public. Some of the comments and predictions are very much personal opinion for a further discussion.

Geometry and Kinematics of the Northern Part of Yeongdeok Fault (영덕단층 북부의 기하와 운동학적 특성)

  • Gwangyeon Kim;Sangmin Ha;Seongjun Lee;Boseong Lim;Min-Cheol Kim;Moon Son
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.1
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    • pp.55-72
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    • 2023
  • This study aims to identify the fault zone architecture and geometric and kinematic characteristics of the Yeongdeok Fault, based on the geometry and kinematic data of various structural elements obtained by detailed field survey and anisotropy of magnetic susceptibility (AMS) of the fault rocks. The Yeongdeok Fault extends from Opo-ri, Ganggu-myeon, Yeongdeok-gun to Gilgok-ri, Maehwa-myeon and Bangyul-ri, Giseong-myeon, Uljin-gun, and cuts various rock types from the Paleo-proterozoic to the Mesozoic with a range of 4.6-5.0 km (4.77 km in average) of right-lateral offset or forms the rock boundaries. The fault is divided into four segments based on its geometric features and shows N-S to NNW strikes and dips of an angle of ≥ 54° to the east at most outcrops, even though the outcrops showing the westward dipping (a range of 54°-82°) of fault surface increase as it goes north. The Yeongdeok Fault shows the difference in the fault zone architecture and in the fault core width ranging from 0.3 to 15 m depending on the bedrock type, which is interpreted as due to differences in the physical properties of bedrock such as ductility, mineral composition, particle size, and anisotropy. Combining the results of paleostress reconstruction and AMS in this and previous studies, the Yeongdeok Fault experienced (1) sinistral strike-slip under NW-SE maximum horizontal principle stress (σHmax) and NE-SW minimum horizontal principle stress (σHmin) in the late Cretaceous to early Cenozoic, and then (2) dextral strike-slip under NE-SW maximum horizontal principle stress (σHmax) and NW-SE minimum horizontal principle stress (σHmin) in the Paleogene. It is interpreted that the deformation caused by the Paleogene dextral strike-slip movement was the most dominant, and the crustal deformation was insignificant thereafter.

Development of a prototype simulator for dental education (치의학 교육을 위한 프로토타입 시뮬레이터의 개발)

  • Mi-El Kim;Jaehoon Sim;Aein Mon;Myung-Joo Kim;Young-Seok Park;Ho-Beom Kwon;Jaeheung Park
    • The Journal of Korean Academy of Prosthodontics
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    • v.61 no.4
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    • pp.257-267
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    • 2023
  • Purpose. The purpose of the study was to fabricate a prototype robotic simulator for dental education, to test whether it could simulate mandibular movements, and to assess the possibility of the stimulator responding to stimuli during dental practice. Materials and methods. A virtual simulator model was developed based on segmentation of the hard tissues using cone-beam computed tomography (CBCT) data. The simulator frame was 3D printed using polylactic acid (PLA) material, and dentiforms and silicone face skin were also inserted. Servo actuators were used to control the movements of the simulator, and the simulator's response to dental stimuli was created by pressure and water level sensors. A water level test was performed to determine the specific threshold of the water level sensor. The mandibular movements and mandibular range of motion of the simulator were tested through computer simulation and the actual model. Results. The prototype robotic simulator consisted of an operational unit, an upper body with an electric device, a head with a temporomandibular joint (TMJ) and dentiforms. The TMJ of the simulator was capable of driving two degrees of freedom, implementing rotational and translational movements. In the water level test, the specific threshold of the water level sensor was 10.35 ml. The mandibular range of motion of the simulator was 50 mm in both computer simulation and the actual model. Conclusion. Although further advancements are still required to improve its efficiency and stability, the upper-body prototype simulator has the potential to be useful in dental practice education.

Performance Evaluation of Monitoring System for Sargassum horneri Using GOCI-II: Focusing on the Results of Removing False Detection in the Yellow Sea and East China Sea (GOCI-II 기반 괭생이모자반 모니터링 시스템 성능 평가: 황해 및 동중국해 해역 오탐지 제거 결과를 중심으로)

  • Han-bit Lee;Ju-Eun Kim;Moon-Seon Kim;Dong-Su Kim;Seung-Hwan Min;Tae-Ho Kim
    • Korean Journal of Remote Sensing
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    • v.39 no.6_2
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    • pp.1615-1633
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    • 2023
  • Sargassum horneri is one of the floating algae in the sea, which breeds in large quantities in the Yellow Sea and East China Sea and then flows into the coast of Republic of Korea, causing various problems such as destroying the environment and damaging fish farms. In order to effectively prevent damage and preserve the coastal environment, the development of Sargassum horneri detection algorithms using satellite-based remote sensing technology has been actively developed. However, incorrect detection information causes an increase in the moving distance of ships collecting Sargassum horneri and confusion in the response of related local governments or institutions,so it is very important to minimize false detections when producing Sargassum horneri spatial information. This study applied technology to automatically remove false detection results using the GOCI-II-based Sargassum horneri detection algorithm of the National Ocean Satellite Center (NOSC) of the Korea Hydrographic and Oceanography Agency (KHOA). Based on the results of analyzing the causes of major false detection results, it includes a process of removing linear and sporadic false detections and green algae that occurs in large quantities along the coast of China in spring and summer by considering them as false detections. The technology to automatically remove false detection was applied to the dates when Sargassum horneri occurred from February 24 to June 25, 2022. Visual assessment results were generated using mid-resolution satellite images, qualitative and quantitative evaluations were performed. Linear false detection results were completely removed, and most of the sporadic and green algae false detection results that affected the distribution were removed. Even after the automatic false detection removal process, it was possible to confirm the distribution area of Sargassum horneri compared to the visual assessment results, and the accuracy and precision calculated using the binary classification model averaged 97.73% and 95.4%, respectively. Recall value was very low at 29.03%, which is presumed to be due to the effect of Sargassum horneri movement due to the observation time discrepancy between GOCI-II and mid-resolution satellite images, differences in spatial resolution, location deviation by orthocorrection, and cloud masking. The results of this study's removal of false detections of Sargassum horneri can determine the spatial distribution status in near real-time, but there are limitations in accurately estimating biomass. Therefore, continuous research on upgrading the Sargassum horneri monitoring system must be conducted to use it as data for establishing future Sargassum horneri response plans.

An Investigation on the self-consciousness Symptoms of the Clerical Workers attendant upon Office Automation (사무 자동화에 따른 사무직 근로자의 건강과 연관된 자각 증상에 대한 조사연구)

  • Jung, Mi Wha
    • Korean Journal of Occupational Health Nursing
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    • v.3
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    • pp.54-70
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    • 1993
  • According as the automation of clerical work(OA ; Office Automation) develops, the use of VDT(Visual or Video Display Terminal) is increasing suddenly. But, in proportion to the spread of office automation(OA tendency), the self-conciousness syptom attendant upon the work is appearing also (Kim, Jung Tae, Lee, Young Ook, 1990). The apparatuses of office enable the clerical workers to be convenient and perform mass businesses. But, they are increasing the opportunity to be exposed to VDT syndrom, techno stress, computer terminal disease, pain by muscle strain(RSI), bradycausia of noise nature, and electromagnetic waves, etc. which are referred to as the new type of occupational diseases to the workers. It is the real situation that the workers to use VDT is complaining of the physical inconvenience sense in the recent newspaper and literature, it is the point of time that the sydrome to come from VDT use and computer terminal disease, etc. must be classified into the occupational disease(Lee, Kwang Young 1990, Lee, Kyoo Hak 1990, Lee, Won Ho 1991, Lee, Si Young 1991, Lee, Joon 1991, Choi, Young Tae 1991, Heo, Seung Ho 1989). In addition, it is the real situation that the scientifitic study result about the scope that electromagnetic waves has influence on the human body has not been suggested yet, and criticism on the stable exposure permission standard about electromagnetic waves to be emitted from VDT and on the problem in the health about electromagnetic waves is continuing. (IEEE Spectrum, 1990). In addition according to the experience of nursery business of industry field, it is the real situation that the patients who consult complaining of physical and mental inconvenience sence, among the users of apparatus of office automation, are reaching 10% of the patients coming to doctor's room. Therefore, it is necessary to confirm the self-consciousness symptom that the clerical workers complain of multilaterally with the actual state examination about the use of the apparatuses of offices automaton. Thus, this study was tried as th basic data for the cosultation and education for the maintenance and furtherance of the health of workers as the nurse of industry field, by confirming the contents of self-consciousness symptom attendant upon the use of the apparatus for office outomation making the financial institution in which the spparatus for office automation in most frequently used as the subject, and by examining whether there is the difference according to the subject of study, the data were collected, by using the questionnaire method, making 200 workers who consented to the study participation as the subject, among the persons who have spent over 3 months since they used the apparatuses for office automation and didn't receive the treatment in hospital due to the clerical disease for recent 3 years. The period of data collection was from Oct. 9, 1991 to Oct. 12. As for the measurement instrument about the complaint if self-consciousness symptom attendant upon the use of apparatuses fo office automation, the question item on the complaint symptom of health problem attendant upon the treatment of VDT that Kim(1991) developed and on CMI health problem and the question items on the fatigue degree due to industry were used by previous examination to 25 persons. Collected data were analyzed with the statistical method such as percentage, arithmetic mean, Person correlation coeffient, Kai square verfication, t-test, ANOVA, etc. by using SPSS/PC+ program, and the result is as follows : 1. The self-consciousness symptom that the clerical workers complained of most frequetly appeared high in 'My eyes are tired'(99.4%), 'I feel fatigue and weariness'(99.4%), 'I feel that my head is heavy5(90.0%), 'eyesight fell'(88.8%), 'I have a stiff neck'(88.8%), 'I fell pain in the shoulder'(85.0%), 'I feel cold and painful in the eyes'(76.9%), 'I feel the dry sense of eyeball'(76.2%), 'My nerves are edgy, and I an fretful, (75.6%), 'I feel pain in the waist'(73.2%) and 'I fell pain in the back'(72.8%). It emerged that the subject use the apparatuses for office automation complained of self-consciousness symptoms related to visual symptoms and musculoskeletal symptoms. 2. As for the general feature of examination subjects, the result to see the distribution by classifying into sex, age, school career, use career of apparatuses for office automation, skillfulness degree of the use of apparatus for office automation, use hours of the apparatuses for office automation per 1 day, type of business of the apparatus for office automation, rest hours during the use of apparatus for office automation, satifaction degree of business of office automation, and work circumstance, etc. emerged as follows : As for the sex of subjects, the distribution showed that men were 58.8% and women were 41.3%, Age was average 26.9. As the distribution of school career, the distribution showed that4below the graduation of high school' was 58.8%, 'graduation from junior college-university' was 35.0%, and 'over graduate school' was 6.3%. In the question to ask the existence or non-existence of experience of health consultation in connection with the work of office automation, the response that I had the consultation exprience and I feel the necessity emergerd as 90.1% And, the case that the subject who didn't wear the glasses or lens before using the OA apparatus wear glasses or lens after using OA apparatus emerged as 28.3% of whole. As for the existence or non-existence of use career of OA apparatus, the case under 3 years was highest as 52. 7%. As for the skillfulnness degree about the use of apparatus for office automation, most of them are skillful with the fact that 'common' was 44.4%, 'skill' was 42.5%, and 'unskillful' was 13.1% As for the use average hours of the apparatus for office automation per 1 day, the distribution showed that the case under 3-6 hours was 33.1%, the case under 6-9 hours was 28.1%, the case under 3 hours was 30.6%, and the case over 9 hours was 8.1% Main OA business and the use hours for 1 day showed in the order of keeping and retrieval, business of information transmission(162min), business of information transmission(79.3 min), business of document framing(55.5 min), and business of duplication and printing(25.4min). as for the rest during the use of apparatus for affice automation, that I take rest occasion demands the major portion, but that I take after completing the work emerged as 33.8%. Though the subiness gets to be convenient by the use of the apparatus for of office automation, respondents who showed the dissatisfaction about the present OA business emergd high as 78.1%. The work circumstances of each office was good with the fact that the temperature of office was 21.8, noise was average 42.7db, and the illumination was average 364.4 lx, in the light of ANSi/HFS 100 Standard. 3. Sight syptom, musculoskeletal symptom, skin and other symptoms showed the significant difference according to the extent of skillfulness of the apparatus for office automation. All the symptoms exept skin symptom showed the difference according to the use hours of the apparatus for office automation. All the question items exept the sytoms of digestive organs and the rest hours during the apparatus for office automation showed the signicant difference. The question item which showed the signicant difference from the satisfaction degree of present OA business showed the significant difference from all the question item classified into 6 groups. But, age and school career didn't significant difference from the complaint of any self-consciousness symptoms.

    . In conclusion, the self-consciousness symptoms of the subjects to use OA apparatus appeared differently, according to sex distiction, skillfull degree of OA apparatus, use hours of OA apparatus, the rest hours during th use of OA apparatus, and the satiafaction degree of persent business. Therefore, it is necessary that the nurse in the inuctry field must recognize to receive the education about the human technological physical condition which is most proper for te use of OA apparatus and about the proper rest method until they get accustomed to the use of OA apparatus. In addition, the simple exercise relax the tention of muscle due to the repetitive simple movement, and the education for the protection of eyesight are necessary.

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  • A Rheological Study on Creep Behavior of Clays (점토(粘土)의 Creep 거동(擧動)에 관한 유변학적(流變學的) 연구(研究))

    • Lee, Chong Kue;Chung, In Joon
      • KSCE Journal of Civil and Environmental Engineering Research
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      • v.1 no.1
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      • pp.53-68
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      • 1981
    • Most clays under sustained load exhibit time-dependent deformation because of creep movement of soil particles and many investigators have attempted to relate their findings to the creep behavior of natural ground and to the long-term stability of slopes. Since the creep behavior of clays may assume a variety of forms depending on such factors as soil plasticity, activity and water content, it is difficult and complicated to analyse the creep behavior of clays. Rheological models composed of linear springs in combination with linear or nonlinear dashpots and sliders, are generally used for the mathematical description of the time-dependent behavior of soils. Most rheological models, however, have been proposed to simulate the behavior of secondary compression for saturated clays and few definitive data exist that can evaluate the behavior of non-saturated clays under the action of sustained stress. The clays change gradually from a solid state through plastic state to a liquid state with increasing water content, therefore, the rheological models also change. On the other hand, creep is time-dependent, and also the effect of thixotropy is time-function. Consequently, there may be certain correlations between creep behavior and the effects of thixotropy in compacted clays. In addition, the states of clay depend on water content and hence the height of the specimen under drained conditions. Futhermore, based on present and past studies, because immediate elastic deformation occurs instantly after the pressure increment without time-delayed behavior, the factor representing immediate elastic deformations in the rheological model is necessary. The investigation described in this paper, based on rheological model, is designed to identify the immediate elastic deformations and the effects of thixotropy and height of clay specimens with varing water content and stress level on creep deformations. For these purposes, the uniaxial drain-type creep tests were performed. Test results and data for three compacted clays have shown that a linear top spring is needed to account for immediate elastic deformations in the rheological model, and at lower water content below the visco-plastic limit, the effects of thixotropy and height of clay specimens can be represented by the proposed rheological model not considering the effects. Therefore, the rheological model does not necessitate the other factors representing these effects. On the other hand, at water content higher than the visco-plastic limit, although the state behavior of clays is visco-plastic or viscous flow at the beginning of the test, the state behavior, in the case of the lower height sample, does not represent the same behavior during the process of the test, because of rapid drainage. In these cases, the rheological model does not coincide with the model in the case of the higher specimens.

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