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The influences of individual personality types on ERP system's acceptance: a preliminary test (개인의 성격유형이 ERP수용에 미치는 영향에 관한 탐색적 연구)

  • Kim, Hyun-Sang;Lee, Jang-Hyung
    • Journal of Korea Society of Industrial Information Systems
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    • v.11 no.4
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    • pp.47-65
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    • 2006
  • The application of the ERP system is becoming more common to the businesses since a firm needs to reinforce positive competitiveness and to maintain competitive advantage. The ERP system is an enterprise integration solution that converts the whole business processes through information technology. Extant research provides plenty of results about the success factors of the ERP system; however, most of the researches focus on the exterior factors such as techniques rather than on the influences that a firm's employees' individual personality has in accepting the information technology of the ERP system. The objective of this study is to investigate the role of the employees' individual personality as a factor that makes the ERP system a success. The surveys--composed of the extent of information technology acceptance about the personality type of MBTI (Myers-Briggs type indicator) and the ERP system--were given to the companies applying the ERP system The personality type of MBTI is measured by 4 types of Myers, and Davis's TAM (technology acceptance model) is used for the information technology acceptance. The results of this study are summarized as follows. First the extraversion and the judging in the personality types of MBTI have a significant influence on the information technology acceptance of the ERP system. However, the thinking and the feeling in the personality types of MBTI were analyzed to not have a critical affect on the ERP system acceptance. Second as verified in the extant research the information technology acceptance verification related to the ERP system has a significant influence on perceived ease of use, perceived usefulness, behavioral intention and actual usage of the ERP system. The results of this study can be used for a successful application of the ERP system as follows. First it offers foundation of perception that the type of the individual personality is a significant key figure for the successful use of the ERP system. Second it provides a basis for the knowledge of combining the model of information technology acceptance and the psychological factors.

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Development of an Automatic Seed Marker Registration Algorithm Using CT and kV X-ray Images (CT 영상 및 kV X선 영상을 이용한 자동 표지 맞춤 알고리듬 개발)

  • Cheong, Kwang-Ho;Cho, Byung-Chul;Kang, Sei-Kwon;Kim, Kyoung-Joo;Bae, Hoon-Sik;Suh, Tae-Suk
    • Radiation Oncology Journal
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    • v.25 no.1
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    • pp.54-61
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    • 2007
  • [ $\underline{Purpose}$ ]: The purpose of this study is to develop a practical method for determining accurate marker positions for prostate cancer radiotherapy using CT images and kV x-ray images obtained from the use of the on- board imager (OBI). $\underline{Materials\;and\;Methods}$: Three gold seed markers were implanted into the reference position inside a prostate gland by a urologist. Multiple digital image processing techniques were used to determine seed marker position and the center-of-mass (COM) technique was employed to determine a representative reference seed marker position. A setup discrepancy can be estimated by comparing a computed $COM_{OBI}$ with the reference $COM_{CT}$. A proposed algorithm was applied to a seed phantom and to four prostate cancer patients with seed implants treated in our clinic. $\underline{Results}$: In the phantom study, the calculated $COM_{CT}$ and $COM_{OBI}$ agreed with $COM_{actual}$ within a millimeter. The algorithm also could localize each seed marker correctly and calculated $COM_{CT}$ and $COM_{OBI}$ for all CT and kV x-ray image sets, respectively. Discrepancies of setup errors between 2D-2D matching results using the OBI application and results using the proposed algorithm were less than one millimeter for each axis. The setup error of each patient was in the range of $0.1{\pm}2.7{\sim}1.8{\pm}6.6\;mm$ in the AP direction, $0.8{\pm}1.6{\sim}2.0{\pm}2.7\;mm$ in the SI direction and $-0.9{\pm}1.5{\sim}2.8{\pm}3.0\;mm$ in the lateral direction, even though the setup error was quite patient dependent. $\underline{Conclusion}$: As it took less than 10 seconds to evaluate a setup discrepancy, it can be helpful to reduce the setup correction time while minimizing subjective factors that may be user dependent. However, the on-line correction process should be integrated into the treatment machine control system for a more reliable procedure.

Determination of shear wave velocity profiles in soil deposit from seismic piezo-cone penetration test (탄성파 피에조콘 관입 시험을 통한 국내 퇴적 지반의 전단파 속도 결정)

  • Sun Chung Guk;Jung Gyungja;Jung Jong Hong;Kim Hong-Jong;Cho Sung-Min
    • 한국지구물리탐사학회:학술대회논문집
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    • 2005.09a
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    • pp.125-153
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    • 2005
  • It has been widely known that the seismic piezo-cone penetration test (SCPTU) is one of the most useful techniques for investigating the geotechnical characteristics including dynamic soil properties. As the practical applications in Korea, SCPTU was carried out at two sites in Busan and four sites in Incheon, which are mainly composed of alluvial or marine soil deposits. From the SCPTU waveform data obtained from the testing sites, the first arrival times of shear waves were and the corresponding time differences with depth were determined using the cross-over method, and the shear wave velocity profiles (VS) were derived based on the refracted ray path method based on Snell's law and similar to the trend of cone tip resistance (qt) profiles. In Incheon area, the testing depths of SCPTU were deeper than those of conventional down-hole seismic tests. Moreover, for the application of the conventional CPTU to earthquake engineering practices, the correlations between VS and CPTU data were deduced based on the SCPTU results. For the empirical evaluation of VS for all soils together with clays and sands which are classified unambiguously in this study by the soil behavior type classification Index (IC), the authors suggested the VS-CPTU data correlations expressed as a function of four parameters, qt, fs, $\sigma$, v0 and Bq, determined by multiple statistical regression modeling. Despite the incompatible strain levels of the down-hole seismic test during SCPTU and the conventional CPTU, it is shown that the VS-CPTU data correlations for all soils clays and sands suggested in this study is applicable to the preliminary estimation of VS for the Korean deposits and is more reliable than the previous correlations proposed by other researchers.

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Function of the Korean String Indexing System for the Subject Catalog (주제목록을 위한 한국용어열색인 시스템의 기능)

  • Yoon Kooho
    • Journal of the Korean Society for Library and Information Science
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    • v.15
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    • pp.225-266
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    • 1988
  • Various theories and techniques for the subject catalog have been developed since Charles Ammi Cutter first tried to formulate rules for the construction of subject headings in 1876. However, they do not seem to be appropriate to Korean language because the syntax and semantics of Korean language are different from those of English and other European languages. This study therefore attempts to develop a new Korean subject indexing system, namely Korean String Indexing System(KOSIS), in order to increase the use of subject catalogs. For this purpose, advantages and disadvantages between the classed subject catalog nd the alphabetical subject catalog, which are typical subject ca-alogs in libraries, are investigated, and most of remarkable subject indexing systems, in particular the PRECIS developed by the British National Bibliography, are reviewed and analysed. KOSIS is a string indexing based on purely the syntax and semantics of Korean language, even though considerable principles of PRECIS are applied to it. The outlines of KOSIS are as follows: 1) KOSIS is based on the fundamentals of natural language and an ingenious conjunction of human indexing skills and computer capabilities. 2) KOSIS is. 3 string indexing based on the 'principle of context-dependency.' A string of terms organized accoding to his principle shows remarkable affinity with certain patterns of words in ordinary discourse. From that point onward, natural language rather than classificatory terms become the basic model for indexing schemes. 3) KOSIS uses 24 role operators. One or more operators should be allocated to the index string, which is organized manually by the indexer's intellectual work, in order to establish the most explicit syntactic relationship of index terms. 4) Traditionally, a single -line entry format is used in which a subject heading or index entry is presented as a single sequence of words, consisting of the entry terms, plus, in some cases, an extra qualifying term or phrase. But KOSIS employs a two-line entry format which contains three basic positions for the production of index entries. The 'lead' serves as the user's access point, the 'display' contains those terms which are themselves context dependent on the lead, 'qualifier' sets the lead term into its wider context. 5) Each of the KOSIS entries is co-extensive with the initial subject statement prepared by the indexer, since it displays all the subject specificities. Compound terms are always presented in their natural language order. Inverted headings are not produced in KOSIS. Consequently, the precision ratio of information retrieval can be increased. 6) KOSIS uses 5 relational codes for the system of references among semantically related terms. Semantically related terms are handled by a different set of routines, leading to the production of 'See' and 'See also' references. 7) KOSIS was riginally developed for a classified catalog system which requires a subject index, that is an index -which 'trans-lates' subject index, that is, an index which 'translates' subjects expressed in natural language into the appropriate classification numbers. However, KOSIS can also be us d for a dictionary catalog system. Accordingly, KOSIS strings can be manipulated to produce either appropriate subject indexes for a classified catalog system, or acceptable subject headings for a dictionary catalog system. 8) KOSIS is able to maintain a constistency of index entries and cross references by means of a routine identification of the established index strings and reference system. For this purpose, an individual Subject Indicator Number and Reference Indicator Number is allocated to each new index strings and new index terms, respectively. can produce all the index entries, cross references, and authority cards by means of either manual or mechanical methods. Thus, detailed algorithms for the machine-production of various outputs are provided for the institutions which can use computer facilities.

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A Study on Relationships Between Environment, Organizational Structure, and Organizational Effectiveness of Public Health Centers in Korea (보건소의 환경, 조직구조와 조직유효성과의 관계)

  • Yun, Soon-Nyoung
    • Research in Community and Public Health Nursing
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    • v.6 no.1
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    • pp.5-33
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    • 1995
  • The objective of the study are two-fold: one is to explore the relationship between environment, organizational structure, and organizational effectiveness of public health centers in Korea, and the other is to examine the validity of contingency theory for improving the organizational structure of public health care agencies, with special emphasis on public health nursing administration. Accordingly, the conceptual model of the study consisted of three different concepts: environment, organizational structure, and organizational effectiveness, which were built up from the contingency theory. Data were collected during the period from 1st of May through 30th of June, 1990. From the total of 249 health centers in the country, one hundred and five centers were sampled non proportionally, according to the geopolitical distribution. Out of 105, 73 health centers responded to mailed questionnaire. The health centers were the unit of the study, and a various statistical analysis techniques were used: Reliability analysis(Cronbach's Alpha) for 4 measurement tools; Shapiro-Wilk statistic for normality test of measured scores of 6 variables: ANOVA, Pearson Correlaion analysis, regressional analysis, and canonical correlation analysis for the test of the relationships and differences between the variables. The results were. as follows : 1. No significant differences between forma lization, decision-making authority and environmental complexity were found(F=1.383, P=.24 ; F=.801, P=.37). 2. Negative relationships between formalization and decision-making authority for both urban and rural health centers were found(r=-.470, P=.002 ; r=-.348, P=.46). 3. No significant relationship between formalization and job satisfaction for both urban and rural health centers were found (r=-.242, P=.132, r=-.060, P=.739). 4. Significant positive relationship between decision - making authority and job satisfaction were found in urban health centers (r=.504, P=.0009), but no such relationship was observed in rural health centers. Regression coefficient between them was statistically significant($\beta=1.535$, P=.0002), and accuracy of regression line was accepted (W=.975, P= .420). 5. No significant relationships among formalization and family planning services, maternal health services, and tuberculosis control services for both urban and rural health centers were found. 6. Among decision-making authority and family planning services, maternal health services, and tuberculosis control services, significant positive relationship was found between de cision-making authority and family planning services(r=.286, P=.73). 7. A significant difference was found in maternal health services by the type of health centers (F=5.13, P=.026) but no difference was found in tuberculosis control services by the type of health centers, formalization, and decision-making authority. 8. A significant positive relationships were found between family planning services and maternal health services and tuberculosis control services, and between maternal health services and tuberculosis control services (r=-.499, P=.001 ; r=.457, P=.004 ; r=.495, P=.002) in case of urban health centers. In case of rural health centers, relationships between family planning services and tuberculosis control services, and between maternal health services and tuberculosis control services were statistically significant (r=.534, P=.002 ; r=.389, P=.027). No significant relationship was found between family planning and maternal health services. 9. A significant positive canonical correlation was found between the group of independent variables consisted of formalization and de cision-making authority and the group of dependent variables consisted of family planning services, maternal health services and tuberculosis control services(Rc=.455, P=.02). In case of urban health centers, no significant canonical correlation was found between them, but significant canoncial correlation was found in rural health centers(Rc=.578, P=.069), 10. Relationships between job satisfaction and health care productivity was not found significant. Through these results, the assumed relationship between environment and organizational structure was not supported in health centers. Therefore, the relationship between the organizational effectiveness and the congruence between environment and organizational structure that contingency theory proposes to exist was not able to be tested. However decision-making authority was found as an important variable of organizational structure affecting family planning services and job satisfaction in urban health centers. Thus it was suggested that decentralized decision making among health professionals would be a valuable strategy for improvement of organizational effectiveness in public health centers. It is also recommended that further studies to test contingency theory would use variability and uncertainty to define environment of public health centers instead of complexity.

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Nondestructive Examination of PHWR Pressure Tube Using Eddy Current Technique (와전류검사 기술을 적용한 가압중수로 원전 압력관 비파괴검사)

  • Lee, Hee-Jong;Choi, Sung-Nam;Cho, Chan-Hee;Yoo, Hyun-Joo;Moon, Gyoon-Young
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.3
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    • pp.254-259
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    • 2014
  • A pressurized heavy water reactor (PHWR) core has 380 fuel channels contained and supported by a horizontal cylindrical vessel known as the calandria, whereas a pressurized water reactor (PWR) has only a single reactor vessel. The pressure tube, which is a pressure-retaining component, has a 103.4 mm inside diameter ${\times}$ 4.19 mm wall thickness, and is 6.36 m long, made of a zirconium alloy (Zr-2.5 wt% Nb). This provides support for the fuel while transporting the $D_2O$ heat-transfer fluid. The simple tubular geometry invites highly automated inspection, and good approach for all inspection. Similar to all nuclear heat-transfer pressure boundaries, the PHWR pressure tube requires a rigorous, periodic inspection to assess the reactor integrity in accordance with the Korea Nuclear Safety Committee law. Volumetric-based nondestructive evaluation (NDE) techniques utilizing ultrasonic and eddy current testing have been adopted for use in the periodic inspection of the fuel channel. The eddy current testing, as a supplemental NDE method to ultrasonic testing, is used to confirm the flaws primarily detected through ultrasonic testing, however, eddy current testing offers a significant advantage in that its ability to detect surface flaws is superior to that of ultrasonic testing. In this paper, effectiveness of flaw detection and the depth sizing capability by eddy current testing for the inside surface of a pressure tube, will be introduced. As a result of this examination, the ET technique is found to be useful only as a detection technique for defects because it can detect fine defects on the surface with high resolution. However, the ET technique is not recommended for use as a depth sizing method because it has a large degree of error for depth sizing.

Mitigation of Greenhouse Gases by Water Management of SRI (System of Rice Intensification) in Rice Paddy Fields (논에서 SRI (System of Rice Intensification) 물 관리 방법을 적용한 온실가스 저감 효과)

  • Kim, Gun-Yeob;Lee, Seul-Bi;Lee, Jong-Sik;Choi, Eun-Jung;Ryu, Jong-Hee
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.1173-1178
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    • 2012
  • Water competition among domestic, industrial and agricultural sectors has been gradually heightened recently in Korea as the lack of water supply is expected in the near future. About 46% of nation's water use is consumed in paddy farming to produce rice. And the conservation of water resource and quality in agricultural sector is a pending issue in the nation's long term water management plan. New paddy rice farming techniques that use significantly less irrigation water are urgently required. System of Rice Intensification (SRI) that is now well known to produce more rice with less water consumption has not been tried in Korea yet. And environmental effect of SRI on greenhouse gases (GHGs) has not been well investigated. The objective of this study was to measure the effect of SRI on GHGs as well as water use and rice yield in a Korean paddy condition. Three experimental runoff plots $5{\times}15m$ in size were prepared at an existing paddy field. Runoff, GHGs emission and water quality were measured during the 2011 growing seasons while a Japonica rice variety was cultivated. Rice plants grew better and healthier in SRI plots than in continuously flooded (CF) and intermittently drained (ID) plots. Rice yield from SRI plots increased 112.8 (ID)~116.1 (CF)% compared with CF and ID plots. Irrigation requirement of SRI plots compared to CF plot reduced by 52.6% and ID plot reduced by 62.0%, meaning that about 37.9~47.4% of irrigation water could be saved. GHGs emission from SRI plots reduced by 71.8% compared to that from CF plot and by 18.4% compared to that from ID plot, meaning that SRI could help contribute to ease the greenhouse gas accumulation in the atmosphere. It was believed that SRI is a promising paddy farming technique that could increase rice yield, and reduce irrigation water requirement and GHGs emission not just in Korea but also other rice farming countries all over the world. However, it was recommended that long term studies under different conditions including rice variety, soil texture, water source, climate need to be conducted for reliable data for the development of environmental policies related to GHGs emission control and management.

Evaluation of Agro-Climatic Index Using Multi-Model Ensemble Downscaled Climate Prediction of CMIP5 (상세화된 CMIP5 기후변화전망의 다중모델앙상블 접근에 의한 농업기후지수 평가)

  • Chung, Uran;Cho, Jaepil;Lee, Eun-Jeong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.17 no.2
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    • pp.108-125
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    • 2015
  • The agro-climatic index is one of the ways to assess the climate resources of particular agricultural areas on the prospect of agricultural production; it can be a key indicator of agricultural productivity by providing the basic information required for the implementation of different and various farming techniques and practicalities to estimate the growth and yield of crops from the climate resources such as air temperature, solar radiation, and precipitation. However, the agro-climate index can always be changed since the index is not the absolute. Recently, many studies which consider uncertainty of future climate change have been actively conducted using multi-model ensemble (MME) approach by developing and improving dynamic and statistical downscaling of Global Climate Model (GCM) output. In this study, the agro-climatic index of Korean Peninsula, such as growing degree day based on $5^{\circ}C$, plant period based on $5^{\circ}C$, crop period based on $10^{\circ}C$, and frost free day were calculated for assessment of the spatio-temporal variations and uncertainties of the indices according to climate change; the downscaled historical (1976-2005) and near future (2011-2040) RCP climate sceneries of AR5 were applied to the calculation of the index. The result showed four agro-climatic indices calculated by nine individual GCMs as well as MME agreed with agro-climatic indices which were calculated by the observed data. It was confirmed that MME, as well as each individual GCM emulated well on past climate in the four major Rivers of South Korea (Han, Nakdong, Geum, and Seumjin and Yeoungsan). However, spatial downscaling still needs further improvement since the agro-climatic indices of some individual GCMs showed different variations with the observed indices at the change of spatial distribution of the four Rivers. The four agro-climatic indices of the Korean Peninsula were expected to increase in nine individual GCMs and MME in future climate scenarios. The differences and uncertainties of the agro-climatic indices have not been reduced on the unlimited coupling of multi-model ensembles. Further research is still required although the differences started to improve when combining of three or four individual GCMs in the study. The agro-climatic indices which were derived and evaluated in the study will be the baseline for the assessment of agro-climatic abnormal indices and agro-productivity indices of the next research work.

A Study on Avant-Garde Fine Art during the period of Japanese Colonial Rule of Korea, centering on 'Munjang' (a literary magazine) (일제강점기 '전위미술론'의 전통관 연구 - '문장(文章)' 그룹을 중심으로)

  • Park, Ca-Rey
    • The Journal of Art Theory & Practice
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    • no.4
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    • pp.57-76
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    • 2006
  • From the late 1920s to the 1930s, Korea's fine art community focused on traditional viewpoints as their main topic. The traditional viewpoints were discussed mainly by Korean students studying in Japan, especially oil painters. Such discussions on tradition can be divided into two separate halves, namely the pre- and post-Sino-Japanese War (1937) periods. Before the war, the modernists among Korea's fine art community tried to gain a fuller understanding of contemporary Western modern art, namely, expressionism, futurism, surrealism, and so forth, on the basis of Orientalism, and borrow from these schools' in order to create their own works. Furthermore, proponents of Joseon's avant-garde fine arts and artists of the pro-fine art school triggered debate on the traditional viewpoints. After the Sino-Japanese War, these artists continued to embrace Western modern art on the basis of Orientalism. However, since Western modern fine art was regressing into Oriental fine art during this period, Korean artists did not need to research Western modern fine art, but sought to study Joseon's classics and create Joseon's own avant- garde fine art in a movement led by the Munjang group. This research reviews the traditional view espoused by the Munjang group, which represented the avant-garde fine art movement of the post-war period. Advocating Joseon's own current of avant-garde fine art through the Munjang literary magazine, Gil Jin - seop, Kim Yong-jun and others accepted the Japanese fine art community's methodology for the restoration of classicism, but refused Orientalism as an ideology, and attempted to renew their perception of Joseon tradition. The advocation of the restoration of classicism by Gil Jin-seop and Kim Yong-jun appears to be similar to that of the Yasuda Yojuro-style restoration of classicism. However, Gil Jin-seop and Kim Yong-jun did not seek their sources of classicism from the Three-Kingdoms and Unified Silla periods, which Japan had promoted as a symbol of unity among the Joseon people; instead they sought classicism from the Joseon fine art which the Japanese had criticized as a hotbed of decadence. It was the Joseon period that the Munjang group chose as classicism when Japan was upholding Fascism as a contemporary extremism, and when Hangeul (Korean writing system) was banned from schools. The group highly evaluated literature written in the style of women, especially women's writings on the royal court, as represented by Hanjungnok (A Story of Sorrowful Days). In the area of fine art, the group renewed the evaluation of not only literary paintings, but also of the authentic landscape paintings refused by, and the values of the Chusa school criticized as decadent by, the colonial bureaucratic artists, there by making great progress in promoting the traditional viewpoint. Kim Yong-jun embraced a painting philosophy based on the painting techniques of Sasaeng (sketching), because he paid keen attention to the tradition of literary paintings, authentic landscape paintings and genre paintings. The literary painting theory of the 20th century, which was highly developed, could naturally shed both the colonial historical viewpoint which regarded Joseon fine art as heteronomical, and the traditional viewpoint which regarded Joseon fine art as decadent. As such, the Munjang group was able to embrace the Joseon period as the source of classicism amid the prevalent colonial historical viewpoint, presumably as it had accumulated first-hand experience in appreciating curios of paintings and calligraphic works, instead of taking a logical approach. Kim Yong-jun, in his fine art theory, defined artistic forms as the expression of mind, and noted that such an artistic mind could be attained by the appreciation of nature and life. This is because, for the Munjang group, the experience of appreciating nature and life begins with the appreciation of curios of paintings and calligraphic works. Furthermore, for the members of the Munjang group, who were purists who valued artistic style, the concept of individuality presumably was an engine that protected them from falling into the then totalitarian world view represented by the Nishita philosophy. Such a 20th century literary painting theory espoused by the Munjang group concurred with the contemporary traditional viewpoint spearheaded by Oh Se-chang in the 1910s. This theory had a great influence on South and North Korea's fine art theories and circles through the Fine Art College of Seoul National University and Pyongyang Fine Art School in the wake of Korea's liberation. In this sense, the significance of the theory should be re-evaluated.

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Research on Mechanized Upland Reclamation Works An Experiment for the Selection of Optimum Teeth Interval and the Analysis of Efficiency of Stumping and Root-Clearing Methods by Rake Dozer. (Report 1) (야산 기계화 개간공법에 관한 연구 -레이크 도저의 적정 이빨 간격의 선택과 발배근작업능률 시험(제1보)-)

  • 류한열;정하우박승우
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.17 no.3
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    • pp.3860-3871
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    • 1975
  • This experiment was carried out to establish the mechanized methods in stumping and root-clearing, which were the most important works in the reclamation of sloping uplands. The determination of optimum teeth interval of rake blades and its operation methods to reduce the quantity of transported topsoil during the works, are the aims of this investigation. A newly designed rake blade, whose net teeth intervals could be regulated by three stages as 15cm, 25cm, and 35cm, was manufactured to attach to the bulldozer of 13ton. The experiments were carried out at Kilsang-Myon, Kwangwha-Gun, from Aug. 9 to Aug. 23, 1975. For each interval, 36 test plots of 50${\times}$10mn in size, which were regulated under three levels of land slopes of 10, 20, and 30% and two different tree stand density of high or medium values, were randomly chosen and arranged by two-replicated split-split plot design. Each stump classified by its diameter was stumped and cleared by the rake dozer to be related between diameter and stumping time. The results obtained in this experiment can be summarized as follows: 1. Stumping times for the diameters ranging from 6 to 18cm of stumps are almost the same and they are not varied by the difference of teeth intervals of rake dozer. 2. By back-ward stumping method, the number of stumps which can be stumped per hour ranges almost from 100 to 170, showing significant difference with respect to the teeth intervals. The working area is sharply varied with not only the stand density of stumps but the teeth intervals. 3. Optimum stumping distance for each teeth interval of rake dozer to minimize the quantity of transported topsoil are varied with such the rates as it is 15m or 20m for 15cm of teeth interval, but 25m for 25cm or 35cm, respectively. The clearing distance could be chosen almost double as long as the operating distance. 4. The working areas per hour of the simultaneous stumping and clearing methods are no significant difference among the various treatments of working conditions, but they are affected by the operating techniques. However, the influencing factors of the working conditions as classified before and the working directions are ranged from 10 to 15 per cent of total working area, respectively. 5. The residual rates of stumps which are not stumped by the rake dozer in each test plot are generally reduced as the teeth interval gets narrower, but there are no significant difference among them. The mean residual rates average to be about 4% for the simultaneous stumping and clearing method. The back-ward stumping method are recommended to be supervised and directed by more than one man, to show the operator where the stumps are located. 6. The results according to the stumping and clearing methods are summarized as Table IV-2. And the selection of working methods is recommended to follow as shown in Fig. IV-9 with respect to the stand density of the field. 7. Generally speaking, the narrower the teeth interval, the better become the working results, but the more the quantity of transported topsoil is increased. Therefore, it is recommended that the teeth interval should be reduced from the present distance of more than 30cm to 25cm or 15cm, by developing suitable working methods through more field works and experiments.

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