• Journal of the Korean Chemical Society
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• v.45 no.5
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• pp.491-499
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• 2001

The purpose of this study was to examine for high school chemistry I textbooks published by the 6th curriculum and some foreign STS programs such as Chemistry in the Community, Science and Technology in Society, Chemistry: The Salter's Approach by analyzing STS contents, students' activity, overall structure of the books and space devoted to STS, and to provide improvement schemes for developing high school chemistry I textbooks to be developed by the 7th curriculum in future. It was found that STS topics in the high school chemistry I textbooks were related only to 'social problems and issues', 'applications of science', 'multiple dimensions of science', and STS contents were presented mostly by narration. Students' activities were limited to discussion and survey, and none of the topics were related to 'career awareness', and 'cooperative work on real problems' in high school chemistry I textbooks. On the contrary, a variety of STS topics and activities such as case study related to local and community, practicing decision-making strategies, role play, practical work career awareness were included in foreign STS programs. Desirable directions for the improvement of STS contents and structure of present high school chemistry I textbooks were proposed in this paper.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2003.05a
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• pp.389-402
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• 2003

미래의 기업 환경은 유형 자산으로서의 물질적인 자산보다는 지적재산권 등의 무형 자산에 대한 중요성이 더욱 강조될 것이다. 지적재산권 중 특허의 가치를 통하여 기업의 성과가 변화함을 보인 많은 선진국의 사례 연구-Machluo(1958)으로부터 시작하여 Mansfield(1965), Beck. R(1976), Parker. J(1978), Rosegger. G(1980), Scherer. F(1980) 등 1990년 이후는 무수히 많음-는 미래 기업 경쟁력이 질적 가치가 우수한 특허를 얼마나 보유하고 이를 얼마나 효율적으로 관리하는가에 달려있음을 보여주고 있다. 본 연구는 국내 화학기업의 특허관리 유형을 5가지 특허 지표들-국내특허출원건수(relative patent applications), 국내특허등록건수(patent granted), 유효특허건수 (valid patents), 집중도(concentration of patents in subclass), 국제특허출원건수(overall international patent applications)-을 통하여 구분하였으며, 이들 변수를 가지고 군집화 하였을 때 각각에 해당하는 클러스터에서 기업성과에 차이가 나타나는지 알아보았다. 본 연구에서 특허를 기업성과와 관련시켜 설명한 점은 기술혁신 능력 내지는 기술경쟁력을 측정하는 척도로서 특허를 바라본 것이며, 특허의 전략적 관리와 활용이 독점적 시장 우위의 확립과 경제적 성과 향상, 통합적인 경쟁력 강화 측면에서 기업의 성공을 가져올 것으로 보기 때문이다.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.442-446
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• 2003

이 연구는 제주도 한림 지역에서 지하수의 수질과 오염의 특성을 규명하고자 시행되었다. 2002년 8월과 11월에 걸쳐 34개 지점에서 지하수 시료를 채취하였고, 이를 분석하여 지하수의 수질을 유형별로 분류하였다. 연구지역은 주로 (Na,Mg)-HCO$_3$ 유형이 나타나며, 일부 지점에서는 Mg-(HCO$_3$+Cl), (Ca,Mg)-HCO$_3$ 유형 등이 나타난다. 이는 지하수의 유동 경로를 따라 서로 다른 수리지화학적 반응이 일어나며, 지표 오염물질의 유입 등이 지하수의 수질에 영향을 미치고 있음을 지시한다. 질산성 질소의 경우, 국내 먹는물 수질기준치 10 mg/L를 초과한 시료는 전체 시료의 8월 조사에서 약 32%, 11월 조사에서 약 27% 이었고, 공간적 분포 특성은 비교적 낮은 고도 150m 이하의 저지대에서 채취한 시료에서 주로 나타났다. 인위적인 오염물질의 유입 가능성이 있는 지점은 전체 시료의 79.4% 이었다.

• Economic and Environmental Geology
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• v.49 no.3
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• pp.167-179
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• 2016

Water quality of Oseepchun, Dogye area, was investigated quantitatively for its origin and hydrogeochemistry in relation to the influence of groundwater. Groundwater appears to be the principal source of Oseepchun from the water-quality monitoring data including redox potentials, composition of dissolved ions and their correlations, hydrogen and oxygen stable isotopic ratios, and the distribution and occurrence of contaminants. Water-quality type of the surface water was grouped by the water-rock interactions as $Ca-HCO_3$ type originated from carbonated bed-rocks in the Joseon Supergroup, (Ca, Mg)-$SO_4$ type related with dissolution of surfide minerals in coal beds of Pyeongan Supergroup, and (Ca, Mg)-($HCO_3$, $SO_4$) type of the mixed one. Locally water pollution occurs by high $SO_4$ from mine drainage and $NO_3$ from waste-treatment facility. Intensive precipitation in summer has no effect on the water type of Oseepchun, but increases the inflow of nitrate and chloride originated from land surface. Results of this study direct that groundwater-surface water interaction is intimate, and thus surface-water resource management should begin with groundwater characterization.

• Journal of the Korean Chemical Society
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• v.57 no.4
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• pp.499-506
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• 2013

In this study, clicker, also known as classroom response system, was applied to the chemistry method course at the university in Gyeongbuk, and preservice chemistry teachers' perceptions of clicker were surveyed. Before starting lecture, operation and class application of clickers were introduced to preservice teachers, and then 4-5 questions were presented to them in most classes during the term. After preservice teachers were asked to answer the questions, lecturer gave feedback based on the class answer distribution. Questions presented to preservice teachers were recall and/or understanding questions on learning contents, opinion questions, and questions about muddiest point. At the end of semester, preservice teachers were asked to rate their perception of clikers in terms of likert scale and essay type. They had positive perceptions of clicker use in aspects of cognitive effects, affective effects and media characteristics. They preferred conceptual understanding questions and monitoring questions among 8 clicker question types. Some cases using clickers in lecture and educational implications were also included.

• Journal of the Korean Chemical Society
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• v.64 no.1
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• pp.38-48
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• 2020

The purpose of this study was to analysis characteristics and changes of epistemic thinking in middle school students on class-argument activities in an argument-based inquiry(ABI) science class. Data was collected from class recording video and activity worksheets of five subjects argument-based inquiry. Results of the analysis of student epistemic cognition characteristics show that experimental data was presented the most as evidence, and depending on the ABI activity, personal experience-based evidence and evidence based on scientific principles were used. As a result of analyzing the changes between claims made before and after class argumentations on five ABI activities in an argument-based inquiry science class, student claim modifications could be classified, according to reasons for the modification, into three types: correcting incorrect claims, clarifying unclear content, and expanding the concept.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.729-744
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• 2023

The value of lithium has significantly increased due to the rising demand for electric cars and batteries. Lithium is primarily found in pegmatites, hydrothermally altered tuffaceous clays, and continental brines. Globally, groundwater-fed salt lakes and oil field brines are attracting attention as major sources of lithium in continental brines, accounting for about 70% of global lithium production. Recently, deep groundwater, especially geothermal water, is also studied for a potential source of lithium. Lithium concentrations in deep groundwater can increase through substantial water-rock reaction and mixing with brines. For the exploration of lithim in deep groundwater, it is important to understand its origin and behavior. Therefore, based on a nationwide preliminary study on the hydrogeochemical characteristics and evolution of thermal groundwater in South Korea, this study aims to investigate the distribution of lithium in the deep groundwater environment and understand the geochemical factors that affect its concentration. A total of 555 thermal groundwater samples were classified into five hydrochemical types showing distinct hydrogeochemical evolution. To investigate the enrichment mechanism, samples (n = 56) with lithium concentrations exceeding the 90th percentile (0.94 mg/L) were studied in detail. Lithium concentrations varied depending upon the type, with Na(Ca)-Cl type being the highest, followed by Ca(Na)-SO₄ type and low-pH Ca(Na)-HCO₃ type. In the Ca(Na)-Cl type, lithium enrichment is due to reverse cation exchange due to seawater intrusion. The enrichment of dissolved lithium in the Ca(Na)-SO₄ type groundwater occurring in Cretaceous volcanic sedimentary basins is related to the occurrence of hydrothermally altered clay minerals and volcanic activities, while enriched lithium in the low-pH Ca(Na)-HCO₃ type groundwater is due to enhanced weathering of basement rocks by ascending deep CO₂. This reconnaissance geochemical study provides valuable insights into hydrogeochemical evolution and economic lithium exploration in deep geologic environments.

• Journal of the Korean Chemical Society
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• v.43 no.6
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• pp.699-706
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• 1999

The purpose of this study was to investigate high school students' conceptions and conceptual types on molecular kinetic theory of gases. Data was collected by a series of semi-structured and in-depth interviews, and has been analyzed. This study showed that the students came to science classes with various prior conceptions of many disciplinary topics. Their conceptual types of their prior knowledge were distinguished as superficial terms-speaking, partial sense-making, and causal sense-making by the degrees of organization and elaboration of conceptual networks. These conceptual types had influence on the ways students understand and think of science, a stability of their conceptions, a tendency to distinguish school science from everyday science, and building a meaning of concept in contexts. It was referred that the students didn't have proper understanding on the nature of scientific knowledge and had been limited their participations as active learners. Therefore, in order for students to experience conceptual change, they must have opportunities of manifesting their own thinking, taking part in discussions, and promoting their motivations and metacognition of knowing and learning science.

• Economic and Environmental Geology
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• v.31 no.3
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• pp.201-213
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• 1998

From the Jungwon and Munkyeong areas which are among the famous producers of the carbonate-type groundwaters in Korea, various kinds of natural waters (deep groundwater, shallow groundwater and surface water) were collected between 1996 and 1997 and were studied for hydrogeochemical and environmental isotope (${\delta}^{34}S_{so4}$, ${\delta}^{18}O$, ${\delta}D$)systematics. Two types of deep groundwaters (carbonate type and alkali type) occur together in the two areas, and each shows distinct hydrogeochemical and environmental isotope characteristics. The carbonate type waters show the hydrochemical feature of the 'calcium(-sodium)-bicarbonate(-sulfate) type', whereas the alkali type water of the 'sodium-bicarbonate type'. The former type waters are characterized by lower pH, higher Eh, and higher amounts of dissolved ions (especialJy, $Ca^{2+}$, $Na^{+}$, $Mg^{2+}$, $HCO_3{^-}$ and $SO_4{^{2-}}$). Two types of deep groundwaters are all saturated or supersaturated with respect to calcite. Two types of deep groundwaters were both derived from pre-thermonuclear (about more than 40 years old) meteoric waters (with lighter 0 and H isotope data than younger waters, i.e., shallow cold groundwaters and surface waters) which evolved through prolonged water-rock interaction. Based on the geologic setting, water chemistry, and environmental isotope data, however, each of these two different types of deep groundwaters represents distinct hydrologic and hydrogeochemical evolution at depths. The carbonate type groundwaters were formed through mixing with acidic waters that were derived from dissolution of pyrites in hydrothermal vein ores (for the Jungwon area water) or in anthracite coal beds (for the Munkyeong area water). If the deeply percolating meteoric waters did not meet pyrites during the circulation, only the alkali type groundwaters would form. This hydrologic and hydrogeochemical model may be successfully applied to the other carbonate type groundwaters in Korea.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.384-387
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• 2004

강원도 지역 탄산수에 대해 혼합에 의한 용존 희유원소의 거동특성 및 탄산염 침전물 형성에 따른 REE 분별작용을 살펴보았다. 탄산수들은 화학적으로 $Na-HCO_3형,\; Ca-Na-HCO_3형\; 및\; Ca-HCO_3$형으로 구분되며, 동위원소조성도 유형에 따라 명확히 구분되는 특징을 보인다. 지화학 및 동위원소 자료의 해석 결과, $Na-HCO_$형 탄산수는 지하심부에서 심부 기원 $CO_2$의 공급에 의해 형성된 반면, 다른 두 유형의 탄산수들은 $Na-HCO_$ 형 탄산수와 천부지하수 간의 혼합에 의해 생성되었음을 지시하였다. 탄산수 내 용존 REE 함량은 물 유형에 따라 변화하지만, ∑REE 함량은 TDS, pH, alkalinity, $\delta^{18}O$$\delta^{18}O$ 및 tritium 함량과 좋은 상관성을 보여주어, 천부 지하수와의 혼합된 특징을 나타내었다. Na-HCO$_3$형 탄산수의 용존 REE 패턴은 강한 HREE 부화를 보여주어 이른바 'S-shape'을 나타내는 반면, $Na-HCO_$ 형은 분산되어 있으며 LREE 부화를 보여주었다. $Ca-Na-HCO_3$형은 약한 HREE 분화 패턴을 보여주었다. 탄산수로부터 침전된 침전물과 침전물을 제거한 잔류물의 REE 패턴은 원 탄산수와 거의 유사한 형태를 보여주어, 탄산염 침전물과 잔류물 간의 REE 분별작용은 일어나지 않았음을 나타낸다.지 않았음을 나타낸다.