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Effective Studying Methods during a School Vacation: A Data Mining Approach (데이타 마이닝을 사용한 방학 중 학습방법과 학업성취도의 관계 분석)

  • Kim, Hea-Suk;Moon, Yang-Sae;Kim, Jin-Ho;Loh, Woong-Kee
    • Journal of KIISE:Software and Applications
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    • v.34 no.1
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    • pp.40-51
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    • 2007
  • To improve academic achievement, the most students not only participate in regular classes but also take various extra programs such as private lessons, private institutes, and educational TV programs. In this paper, we propose a data mining approach to identify which studying methods or usual life patterns during a school vacation affect changes in the academic achievement. First, we derive various studying methods and life patterns that are thought to be affecting changes in the academic achievement during a school vacation. Second, we propose the method of transforming and analyzing data to apply them to decision trees and association rules, which are representative data mining techniques. Third, we construct decision trees and find association rules from the real survey data of middle school students. We have discovered four representative results from the decision trees. First, for students in the higher rank, there is a tendency that private institutes give a positive effect on the academic achievement. Second, for the most students, the Internet teaming sites nay give a negative effect on the achievement. Third, private lessons that have thought to be making a large impact to the achievement, however, do not make a positive effect on the achievement. Fourth, taking several studying methods in parallel nay give a negative effect on the achievement. In association rules, however, we cannot find any meaningful relationships between academic achievement and usual life patterns during a school vacation. We believe that our approach will be very helpful for teachers and parents to give a good direction both in preparing a studying plan and in selecting studying methods during a school vacation.

Analysis of Curriculum in the Field of Clothing Construction Fashion Related Courses -Focusing on Four-year Domestic University- (패션 관련 학과 의복구성분야 교육과정 현황분석 -국내 4년제 대학을 중심으로-)

  • Kim, KyungAe;Cho, KyeongSook
    • Journal of the Korean Society of Clothing and Textiles
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    • v.41 no.2
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    • pp.242-253
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    • 2017
  • We selected 81 universities (39.1%) for research and close analysis to analyze the current availability of courses in the field of clothing construction at four-year domestic universities. The results of the analysis shows that curriculum is currently composed of theoretical and practical courses that continue to be developed in diverse areas of study. Despite having classes with underlying similarities and differences, research shows that the course curriculum is constructed systematically with both theory and practice at each stage. Distribution of curriculum in the field of clothing construction were organized and analyzed by similar courses in 4 larger groupings and 9 sub-groups. Analysis of the large groupings showed that sewing courses (19.8%), pattern development courses (41.0%), advanced sewing courses (14.1%), and miscellaneous courses (26.1%) were established. Analysis of the sub-groups showed that basic theory and sewing courses (3.6%), sewing courses (16.1%), flat pattern courses (17.9%), draping pattern courses (14.6%), pattern CAD courses (7.3%), tailoring and advanced sewing courses (8.5%), scientific sewing and apparel production processing courses (1.4%), special sewing courses (3.9%), and miscellaneous and new subject courses (26.1%) were established. Overall analysis of the organization distribution was conducted in the order of pattern development (39.9%), miscellaneous & new subject (26.1%), basic theory and sewing (19.8%), and advanced sewing (14.0%). Field analysis from various angles indicates that pattern development, new subject courses, and miscellaneous courses had a relatively higher proportion than other major courses. From this it can be inferred that this trend is an effort to develop individuals to adapt to a rapidly changing fashion industry and environment. The composition of courses also shows great advancement towards diversification and course development. However, there is still insufficient exchange between industrial and education sites. As active exchange continue to be demanded, classification standards for new subject courses and titles of such studies have become unclear and have reached limitations.

Mechanism of Protoporphyrinogen Oxidase-inhibiting Herbicide, Oxyfluorfen Tolerance in Squash leaves of Various Ages (Protoporphyrinogen Oxidase 저해형 제초제 Oxyfluorfen에 대한 호박 엽령별 내성기작)

  • Kuk, Yong-In;Yun, Young-Beom
    • Korean Journal of Weed Science
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    • v.30 no.2
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    • pp.111-121
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    • 2010
  • Differential tolerance to protoporphyrinogen oxidase (Protox)-inhibiting herbicides, oxyfluorfen was observed between leaf ages in squash. Physiological responses to oxyfluorfen, including leaf injury, cellular leakage, accumulation of tetrapyrroles, and antioxidative enzymes activity, were investigated in leaf age classes of squash to identify mechanisms of oxyfluorfen tolerance. Leaf 1, 2, and 3 injuries for Joongangaehobak were >10,000, 1,286, and 1.6-fold higher than that of leaf 4, after treatment of oxyfluorfen. On the other hand, leaf 1, 2, and 3 injuries for Sintowjahobak were 725, 366, and >0.6-fold higher than that of leaf 4, after treatment of oxyfluorfen. However, in contrast to oxyfluorfen treatment results, leaf injury of squash leaf 4 treated with paraquat was much smaller than in leaves 1, 2 and 3. Electrolyte leakage from the tissues treated with oxyfluorfen was higher in the youngest leaf (Leaf 4) than in the older leaves 1, 2, and 3. Differential leaf response to oxyfluorfen of squash appears to be due in large part to differences in protoporphyrin IX (Proto IX), Mg-Proto IX, and Mg-Proto IX monomethyl ester accumulation in treated leaves. In contrast, leaf 4 had higher activities of superoxide dismutase, catalase, peroxidase, ascorbate peroxidase, and glutathione reductase than leaf 1 after treatment with oxyfluorfen. However, the induction in antioxidant activity in leaf 4 was not enough to overcome the toxic effects of a Protox inhibitor, oxyfluorfen, so the leaf eventually died.

Spatial Distribution Pattern of the Populations of Cephalanthera erecta at Mt. Ahop in Busan (부산시 아홉산의 은난초 집단의 공간적 분포 양상)

  • Huh, Man Kyu
    • Journal of Life Science
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    • v.26 no.8
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    • pp.881-886
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    • 2016
  • Cephalanthera erecta (Thunb. ex, Murray) is an herbaceous and a member of the genus Cephalanthera in the family Orchidaceae. The species is an herbaceous and has reputed Chinese medicinal value. It has been investigated the population density and spatial distribution of this species at Mt. Ahop in Korea during 2015. The spatial pattern of C. erecta was analyzed according to several patchiness indexes, population uniformity or aggregation under different sizes of plots by dispersion indices, and spatial autocorrelation. The mean crowding (M*) and patchiness index (PAI) showed positive values except one small plot (2 m × 2 m). Most natural individuals of C. erecta for plots were not uniformly distributed in the forest community. The small plots (2 m × 2 m, to 8 m × 16 m) of C. erecta were uniformly distributed in the forest community and large plots (16 m × 16 m and 16 m × 32 m) were aggregately distributed. Significant aggregations by Moran's I of C. erecta were partially observed within IV classes (12 m). Dissimilarity among pairs of individuals could found by more than 18.0 m. In conclusion, the geographic distribution of C. erecta is not even with varying degrees of size of plots and human activities give rise to density effects in the plots at Mt. Ahop in Korea.

Composition and Structure of the Major Forest Stands in Mt. Worak, Korea: On the National Long-Term Ecological Research Sites (월악산 주요 임분의 종조성과 구조: 국가장기생태연구지소를 중심으로)

  • Cho, Hyun-Je;Lee, Jung-Hyo;Bae, Kwan-Ho
    • Journal of Ecology and Environment
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    • v.29 no.6
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    • pp.531-537
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    • 2006
  • We assessed the species composition and structure of the three representative forest stands(Pinus densiflora stand, Quercus variabilis stand, and Ouercus mongolica stand), dominated in the National Long-Term Ecological Research Sites of Mt. Worak, Korea and established a benchmark series of permanent plots and transects with which future changes in forest composition and structure could be monitored. Species richness of Q. mongolica stand was greater than other two stands, due in large part to the greater habitat heterogeneity. Number of trees and species are decreased with increasing DBH classes. The successional trends of the three study stands would be mostly changed as Q. mongolica forest, regardless of forest types. Mean density ratio between alive trees and dead trees of three forest stands appeared with Q. mongolica stand 75:25, Q. variabilis stand 94:6, and P. densiflora stand 86:14, Q. mongolica stand appeared most highly from in three stands. This may be due to interspecific or intraspecific competition that it follows in various successesional stages. One side, when it saw the tree status which shows the tree health, the three forest stands all standing alive type (AS) appeared most highly with 75% to 85% and fallen dead type (DF) did not appear entirely. Remeasurement of permanent plots at periodic intervals will provide useful information on the dynamics of the forest vegetation that can be used in the development of adaptive conservation plans.

A Study on the Interpretalion of the Synthetic Unit Hydrograph According to the Characteristics of catchment Area and Runoff Routing (유역 특성과 유출추적에 의한 단위도 해석에 관한 고찰)

  • 서승덕
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.8 no.1
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    • pp.1088-1096
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    • 1966
  • The following is a method of synthetic unitgraph derivation based on the routing of a time area diagram through channel storage, studied by Clark-Jonstone and Laurenson. Unithy drograph (or unitgraph) is the hydrograph that would result from unit rainfall\ulcorner excess occuring uniformly with respect to both time and area over a catchment in unit time. By thus standarzing rainfall characteristics and ignoring loss, the unitgraph represents only the effects of catchment characteristics on the time distribution of runoff from a catchment The situation abten arises where it is desirable to derive a unitgraph for the design of dams, large bridge, and flood mitigation works such as levees, floodways and other flood control structures, and are also used in flood forecasting, and the necessary hydrologie records are not available. In such cases, if time and funds permit, it may be desirable to install the necessary raingauges, pruviometers, and stream gaging stations, and collect the necessary data over a period of years. On the otherhand, this procedure may be found either uneconomic or impossible on the grounds of time required, and it then becomes necessary to synthesise a unitgraph from a knowledge of the physical charcteristics of the catchment. In the preparing the approach to the solution of the problem we must select a number of catchment characteristic(shape, stream pattern, surface slope, and stream slope, etc.), a number of parameters that will define the magnitude and shape of the unit graph (e.g. peak discharge, time to peak, and base length, etc.), evaluate the catch-ment characteristics and unitgraph parameters selected, for a number of catchments having adequate rainfall and stream data and obtain Correlations between the two classes of data, and assume the relationships derived in just above question apply to other, ungaged, Catchments in the same region and, knowing the physical characteritics of these catchments, substitute for them in the relation\ulcorner ships to determine the corresponding unitgraph parameters. This method described in this note, based on the routing of a time area diagram through channel storage, appears to provide a logical line of research and they allow a readier correlation of unitgraph parameters with catchment characteristics. The main disadvantage of this method appears to be the error in routing all elements of rainfall excess through the same amount of storage. evertheless, it should be noted that the synthetic unitgraph method is more accurate than the rational method since it takes account of the shape and tophography of the catchment, channel storage, and temporal variation of rainfall excess, all of which are neglected in rational method.

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Partial Characterization of Two Cathepsin D Family Aspartic Peptidases of Clonorchis sinensis

  • Kang, Jung-Mi;Yoo, Won-Gi;Le, Huong Giang;Thai, Thi Lam;Hong, Sung-Jong;Sohn, Woon-Mok;Na, Byoung-Kuk
    • Parasites, Hosts and Diseases
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    • v.57 no.6
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    • pp.671-680
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    • 2019
  • Cathepsin D (CatD, EC 3.4.23.5) is a member belonging to the subfamily of aspartic endopeptidases, which are classified into the MEROPS clan AA, family A1. Helminth parasites express a large set of different peptidases that play pivotal roles in parasite biology and pathophysiology. However, CatD is less well known than the other classes of peptidases in terms of biochemical properties and biological functions. In this study, we identified 2 novel CatDs (CsCatD1 and CsCatD2) of Clonorchis sinensis and partially characterized their properties. Both CsCatDs represent typical enzymes sharing amino acid residues and motifs that are tightly conserved in the CatD superfamily of proteins. Both CsCatDs showed similar patterns of expression in different developmental stages of C. sinensis, but CsCatD2 was also expressed in metacercariae. CsCatD2 was mainly expressed in the intestines and eggs of C. sinensis. Sera obtained from rats experimentally infected with C. sinensis reacted with recombinant CsCatD2 beginning 2 weeks after infection and the antibody titers were gradually increased by maturation of the parasite. Structural analysis of CsCatD2 revealed a bilobed enzyme structure consisting of 2 antiparallel β-sheet domains packed against each other forming a homodimeric structure. These results suggested a plausible biological role of CsCatD2 in the nutrition and reproduction of parasite and its potential utility as a serodiagnostic antigen in clonorchiasis.

Estimation of Smoking Prevalence among Adolescents in a Community by Design-based Analysis (설계기준 분석 방법에 의한 지역사회 청소년 흡연율 추정)

  • Park, Soon-Woo;Lee, Sang-Won;Park, Jung Han;Yun, Yeon-Ok;Lee, Won-Kee;Kim, Jong-Yeon
    • Journal of Preventive Medicine and Public Health
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    • v.39 no.4
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    • pp.317-324
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    • 2006
  • Objectives: This study was conducted to estimate the unbiased smoking prevalence and its standard errors among adolescents in a large city in Korea, by design-based analysis. Methods: All the students in Daegu city were stratified by grade, gender and region, and then schools as primary sampling units (PSU) were selected by probability proportional to size (PPS) sampling. One or two classes were sampled randomly from each grade, from 5th grade in elementary schools to the 3rd grade in high schools. The students anonymously completed a standardized self-administered questionnaire from October to December 2004. The total number of respondents was 8,480 in the final analysis, excluding the third graders in the general high schools because of incomplete sampling. The sampling weight was calculated for each student after post-stratification adjustment, with adjustment being made for the missing cases. The data were analyzed with Stata 8.0 with consideration of PSU, weighting and the strata variables. Results: The smoking prevalence (%) and standard errors for male students from the fifth grade in elementary schools to the second grade in high schools were $0.93{\pm}0.47,\;1.83{\pm}0.74,\;3.16{\pm}1.00,\;5.12{\pm}1.02,\;10.86{\pm}1.13,\;15.63{\pm}2.44\;and\;17.96{\pm}2.67$, and those for the female students were $0.28{\pm}0.28,\;1.17{\pm}0.73,\;3.13{\pm}0.60,\;1.45{\pm}0.58,\;3.94{\pm}0.92,\;8.75{\pm}1.86\;and\;10.04{\pm}1.70$, sequentially. Conclusions: The smoking prevalence from this study was much higher than those from the other conventional studies conducted in Korea. The point estimates and standard errors from the design-based analysis were different from those of the model-based analysis. These findings suggest the importance of design-based analysis to estimate unbiased prevalence and standard errors in complex survey data and this method is recommended to apply to future surveys for determining the smoking prevalence for specific population.

A Study on the Characteristics of Future Schools for Students with Future Convergent STEAM Talents (미래 융합형 과학기술인재(STEAM)를 위한 미래학교 특성 탐색)

  • Kwak, Misun;Kwak, Youngsun;Lee, Soo-Young
    • Journal of The Korean Association For Science Education
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    • v.39 no.4
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    • pp.479-488
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    • 2019
  • The purpose of this research is to derive competencies necessary for students with future convergent STEAM talents, and to explore ideal student images, teaching-learning strategies, evaluation methods, and teachers' competencies and their training methods for future schools developing students' competencies. In order to figure out the features of the future schools, 25 experts from related fields, including in-service teachers, administrators, and college students in science and technology, participated in a future workshop. According to the results, students with future convergent science and technology talents are expected to have flexible thinking and creative thinking competencies to solve problems in innovative ways rather than traditional ways. In other words, it takes the power to accept and accommodate unexpected situations and solve problems appropriately in those situations. To cultivate such competencies, therefore, future schools should also be flexible and proactive. Rigid schools delivering knowledge-based information make it impossible to cultivate flexible and creative talents. Future schools should change into leaner-centered project-based classes so that students can naturally cope with various situations and solve large and small problems, and prepare assessment systems that can provide feedback based on the student's performances rather than achievement standards.

Proposal of a Classification System of Checklists for Safety Management of On-Site Workers in Modular Construction (사례분석을 통한 모듈러 건축의 현장 작업자 안전관리 체크리스트의 분류 체계 제안)

  • Jun, Younghun;Kim, Kyoontai;Jeon, Eunbi
    • Korean Journal of Construction Engineering and Management
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    • v.22 no.6
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    • pp.120-130
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    • 2021
  • Recently, the government is reinforcing safety management at construction sites to prevent safety accidents in construction works, and the safety management plan of workers is an important situation. Meanwhile, modular construction is expected to be gradually expanded to middle and high-rise buildings, but active measures to ensure worker safety are insufficient. This study is a preliminary study of the development of a checklist for preventive worker safety management. The purpose of this study is to derive a checklist classification system for the safety management of workers in the field of modular construction by preceding studies, case analysis, and expert advisory opinions. The classification system consists of large categories of factory manufacturing, transportation, and on-site construction, and the sub-system consists of six sub-classes: foundation work, frame work, modular frame installation work, finishing work, and facility work. Among them, the sub-classification of modular frame installation work consists of 12 unit works, centering on module lifting and assembly module work, which are the main construction processes. And the classification system reflects the three main management factors and contents for defined safety management. It is expected that the research results of this study can contribute to efficient safety management at the modular construction site.