• Journal of the korean Society of Automotive Engineers
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• v.15 no.1
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• pp.28-36
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• 1993

Present-day there are two of theories which have considerable scientific support to explain the knock phenomenon in S.I. engine, the detonation theory and the autoignition theory. But they still have some problems to explain effects of knock parameters, i.e.. compression ratio, spark timing, mixture quality, engine speed, ect, on knocking process in S.I. engine. Accordingly, it is essential to find out whish is more adequate theory of two and to develop the method of analyzing knock phenomenon, that is the aim of this paper. The Authors develop the method of predicting transient temperature and pressure at the end-gas zone during the combustion period and analyze knocking process by this method based on the knock theories. The caluculated values based on the autoignition theory show reasonablly correct relations between knock parameters and knock process but there is no evidence of knock occurred by detonation theory through the calculation according to the all parameters. The authors find out that the autoignition theory is more adequate than detonation theory to analyze knocking process in S.I. engine.

• Korean Journal of Child Studies
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• v.22 no.2
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• pp.375-390
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• 2001

본 연구는 혼잣말이 유아들의 인지적 과정에 중요한 역할을 한다는 비고츠키의 이론을 검증하는데 그 목적이 있다. 비고츠키의 혼잣말에 관한 이론을 확인하고자 하는 선행연구들은 일관된 결과를 보이지 못해 왔다. 이에 본 연구에서는 두 가지 과제해결조건, 즉 혼잣말을 억제하는 경우와 혼잣말을 격려하는 조건하에서 두 종류의 과제를 수행할 경우, 유아들의 혼잣말의 발생 빈도와 과제수행력은 어떠한 양상으로 나타나는지를 알아봄으로써 혼잣말의 인지적 기능을 확인하고자 한다. 30명의 5세 유아들을 대상으로 하여 이루어진 본 연구의 결과는 다음과 같았다. 유아들이 자발적으로 사용하는 혼잣말은 혼잣말이 적극 격려되는 조건일 때 그리고 언어적 과제유형보다는 공간-지각적 과제유형에서 더 높은 빈도로 관찰되었으며 높게 나타난 혼잣말은 공간-지각적 과제의 수행력에 긍정적인 영향을 보였다. 이는 비고츠키의 주장대로, 유아들의 혼잣말에 인지적 자기조절 기능이 있음을 지지하는 결과로 해석된다.

• School Mathematics
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• v.18 no.3
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• pp.733-747
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• 2016

To describe mathematics learning relying on a priori assumptions about the learners has a risk of assuming the learners as well-prepared subjects. In this study we investigate the epistemological perspective of Gilles Deleuze which is expected to give overcome this risk. Then we analyze the constructivist's epistemology and prior discussions about learning mathematics in the preceding studies accordingly. As a result, a priori assumption on which students are regarded as well-prepared for learning mathematics is reconsidered and we propose a new model of thought to highlight the involuntary aspect of the occurrence of thinking facilitated by the encounter with mathematical signs. This perspective gives a new vision on involuntary aspects of mathematics learning and the learner's confusion or difficulty at the starting point of learning.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.12
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• pp.3326-3334
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• 1994

To theoretically predict knock occurrence in S. I. engine as a function of engine design and operating parameters, transient local temperature and pressure, mixture density of flame front in combustion period are calculated. We next determined normal combustion period and auto ignition period of end gas using the prediction method on occurrence of spark knock which we suggested. We predict knock occurrence in S. I. engine by comparing consecutively normal combustion period with the auto ignition period of end gas in combustion period. Engine design and operating parameters such as compression ratio, engine speed, spark timing, inlet temperature and pressure are taken into account in this calculations. The predicted result are well matched with the experimental results in turbocharged engine. Therefore, this method will provide the systematic guideline for designing engines in view of knocking limits.

• Journal of the Korean Magnetics Society
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• v.17 no.3
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• pp.114-119
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• 2007

The single crystal $Nd_3Se_4$ with the $bcc-Th_3P_4$ type structure is grown and the temperature dependent magnetic susceptibilities are measured between 4 K and 300 K. The experimental data are compared with the theoretically calculated susceptibilities which depend on the splitting energies of the $Nd^{3+}$ ground state under the crystal field effect. We find that the magnetic susceptibility of the $Nd^{3+}$ ion in $Nd_3Se_4$ is not affected by the crystal field effect. The spontaneous magnetization curve below $T_c\;=\;53\;K$ of $Nd_3Se_4$ corresponds to the Brillouin function of $Nd_3Se_4$ with J=9/2.

• Journal of Korean Library and Information Science Society
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• v.55 no.1
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• pp.173-192
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• 2024

Through a survey of college students, this study explained the process and aspects of how Generation Z interacted with information while collaborating on a daily basis. Applying the Radical Change Theory, the study investigated the platforms through which university students engaged in challenges and their information behaviors. University students primarily participated in challenges using platforms such as Instagram and Naver Blog. In terms of changes in information seeking, which is the first type of information seeking in the theory, a wide and diverse range of information behaviors were observed, with the way of searching for information being quite different from when the digital age arrived 10 years ago. Information sources included not only digitalized ones but also traditional sources such as printed materials and personal contacts. The utilization of various media types was prominent, and collaborative efforts were voluntarily undertaken for challenges. In terms of changing perspectives, type 2 of information behavior, the main motivation for acquiring information and securing knowledge led to participation in the challenge. Participants exhibited a sense of community consciousness, including mutual influence awareness, social participation consciousness, and emotional connection.

• Journal of Korean Society of Archives and Records Management
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• v.4 no.1
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• pp.23-42
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• 2004

Lenin's decree of 1 June 1918 'On the reorganization and centralization of archives in the RSFRS' is appreciated as an institutional and conceptional basis for Socialist archival theory and practice not only in USSR but also in most countries of the socialist community. In spite of its importance to the making role to build the 'landmark' in the history of russian archives. This paper focuses on the activities and achievements of archivists in 'RAD Union(Union of Russian archives activists)' in revolutionary situation of 1917-1920. To preserve documental heritage with historical values in difficult situation of 1917 historians and archivists in 'RAD Union' voluntarily cooperated with new governments. This special situation led them to make more efforts at reformulating national archival system, namely, the state Archival Fond (Gosudarstvennyi Arkhivnyi Fond) as a new base for the centralization and arrangement of all archival materials throughout the country. Their experience was reflected in every articles of the archival decree of June 1918.

• Knowledge Management Research
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• v.23 no.3
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• pp.153-171
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• 2022

With the global ESG management craze, domestic and foreign companies voluntarily declare sustainable management and actively respond by establishing strategies. The Financial Services Commission mandates the disclosure of sustainability reports representing ESG management sequentially and will expand to SMEs in the future. Information disclosure of sustainability reports is mainly done through international standards such as GRI, SASB, and TCFD, and many domestic companies use GRI Standards guidelines. This study examines the composition system of sustainability reports and compares public and private companies with GRI Standards to analyze sustainable management by type. This study revealed that public enterprises focused on social and labor, while private enterprises focused on the economy and environment through TF-IDF modeling. In addition, the electronic and information communication industries focused on product responsibility. Unlike previous studies that quantified and analyzed sustainability management according to grade, the current study analyzed sustainability reports, which are unstructured data. Therefore, the results of this study are expected to provide valuable theoretical and practical implications for researchers and supervisors interested in ESG management.

• Journal of the Korean School Mathematics Society
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• v.8 no.2
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• pp.291-314
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• 2005

The purpose of this paper was to investigate the difficulties experienced by the novice elementary school teachers in the mathematics classes and suggest some implications for teacher education and effective adaptation of novice teachers. The researchers observed mathematics lessons of 6 novice elementary school teachers and interviewed on the difficulties that they experience in teaching mathematics. The data were collected by lesson observations, interviews, discussion and email communications and categorized the data the types of difficulties those the teachers experience. The difficulties were difference between theory and practice, explanation, questioning, differentiated lesson, application of teaching method, evaluation, and understanding of mathematics. The implication from this study is that novice teachers need to supported by the administration as well as actively participate at various types of educational meetings.

• Proceedings of The Korean Society of Health Promotion Conference
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• 1999.07a
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• pp.9-36
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• 1999

21C기를 맞이하면서 미국의 보건소가 당면한 과제는 시민들을 상해질병에서 보호하고 예방하는 것이다. 금세기 초 남녀 평균수명은 50세에 불과하였으나 후반에 이르러서는 남자 평균 수명 72세, 여자 79세로 늘어나게 되었는데 이것은 공중보건의 기여라고 볼 수 있다. 지난 10년 동안 미국의 보건의료정책은 격변기를 맞았으며 지역사회 병원들은 점차 보건소 활동분야인 예방사업에도 침투하고 있어서 지방보건소 활동과 경쟁하게 되었다. 이로 인하여 지방보건소는 지역사회에서 보다 광범위한 보건증진계획을 세워야 했고 동반자의 참여를 절실해하고 있다. 미국 의학연구소는 "공중보건의 장래" 라는 지침서를 발간하였고 10대 필수보건수칙이 지방보건소를 위하여 정해졌다. 이를 수행하기 위해선 지방보건소가 갖추어야 할 사항은 1) 건강 평가 2) 정책수립 3) 행정력 4) 건강증진 계획 5) 시민건강 보호대책 6) 질적 확인 체재수립 7) 직원교육 훈련 8) 지역사회 자발력 및 참여 고취 등이 있다. 보건교육 사업이란 그 과제와 재능과 개념 등이 다양해 이의 포괄적인 수용이 모색되어야하며, 그래서 이 논문은 건강증진 사업에 대한 "새 눈의 시야"와 같다고 볼 수 있다. "보건교육/보건증진" 이란 공중보건의 이론과 실제를 일체화하는데 있다고 볼 수 있다. 미국은 2010년 보건의료 정책수립에 "건강증진/ 보건교육" 역할을 문서화하였고, "보건교육/ 건강증진" 사업은 지역사회 안에서 체계화하여 "건강한 사회에 건강한 시민" 이라는 사회운동의 청사진으로 이어지고 있다. 이 논문은 콜로라도의 "건강한 사회에 건강한시민" 운동을 한 예로 들고 있으며 "보건교육/건강증진" 사업에 대한 표준 설정을 위하여 노스캐롤라이나주 지방보건소의 "보건교육/건강증진" 표준체제를 예로 들었다. 다음으로, 경제적인 효율면에서 볼 때 "보건교육/건강증진" 사업에는 단기 혹은 장기 투자가치가 있는가 하는 것이다. 새로 태어나는 미국 지방 보건소의 "보건교육/건강증진" 활동은 지역 시민 및 그 단체가 광범위하고도 자연 다발적으로 참여할 때만 성공할 수 있다고 결론 지울 수 있다.