• Title/Summary/Keyword: Hypothesis-generating

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Forecast of Areal Average Rainfall Using Radiosonde Data and Neural Networks (상층기상자료와 신경망기법을 이용한 면적강우 예측)

  • Kim Gwang-Seob
    • Journal of Korea Water Resources Association
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    • v.39 no.8 s.169
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    • pp.717-726
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    • 2006
  • In this study, we developed a rainfall forecasting model using data from radiosonde and rain gauge network and neural networks. The primary hypothesis is that if we can consider the moving direction of the rain generating weather system in forecasting rainfall, we can get more accurate results. We assume that the moving direction of the rain generating weather system is same as the wind direction at 700mb which is measured at radiosonde networks. Neural networks are consisted of 8 different modules according to 8 different wind directions. The model was verified using 350 AWS data and Pohang radiosonde data. Correlation coefficient is improved from 0.41 to 0.73 and skill score is 0.35. Statistical performance measures of the Quantitative Precipitation Forecast (QPF) model show improved output compared to that of rainfall forecasting model using only AWS data.

The Role of the Cauchy Probability Distribution in a Continuous Taboo Search (연속형 타부 탐색에서 코시 확률 분포의 역할)

  • Lee, Chang-Yong;Lee, Dong-Ju
    • Journal of KIISE:Software and Applications
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    • v.37 no.8
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    • pp.591-598
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    • 2010
  • In this study, we propose a new method for generating candidate solutions based on the Cauchy probability distribution in order to complement the shortcoming of the solutions generated by the normal distribution. The Cauchy probability distribution has infinite mean and variance, and it has rather large probability in the tail region relative to the normal distribution. Thus, the Cauchy distribution can yield higher probabilities of generating candidate solutions of large-varied variables, which in turn has an advantage of searching wider area of variable space. In order to compare and analyze the performance of the proposed method against the conventional method, we carried out an experiment using benchmarking problems of real valued function. From the result of the experiment, we found that the proposed method based on the Cauchy distribution outperformed the conventional one for all benchmarking problems, and verified its superiority by the statistical hypothesis test.

The Content Analysis of the Elementary Science Textbooks in the 6th National Curriculum (제 6차 교육과정에 의한 초등학교 자연 교과서의 내용 분석)

  • 최영란;이형철
    • Journal of Korean Elementary Science Education
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    • v.17 no.2
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    • pp.55-65
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    • 1998
  • This study was intended to suggest the desirable direction in the 7th national curriculum revision through the analysis of the elementary science textbooks in the 6th national curriculum. The analysis system was composed of three categories, (1)knowledge (2)inquiry process and (3)attitude. And knowledge was divided into fact, concept and rule. And inquiry process was divided into thirteen subcategories such as manipulating experimental apparatus, observing, measuring, recording data, classifying, interpreting/ predicting, determining relationship/ causal explanation, extrapolating/ interpolating, drawing conclusions/ formulating a generalization or model, evaluating, formulating a problem, generating a hypothesis and designing an experiment/ controlling variables. Each sentence in the textbooks was considered as an analyzing unit. The frequency and percentage of each category were counted and the ratios were calculated. The findings could be summarized as follows: 1. The content of the elementary science textbooks was composed of knowledge 10.3%, inquiry process 88.8%, attitude 0.8% respectively. 2. As increasing the grades, the ratio of knowledge showed high frequency, but that of attitude showed low frequency. 3. In All the grades, the ratio of observing was the highest in inquiry process. 4. In the domain of physics and chemistry, the manipulating experimental apparatus showed high frequency. In the domain of biology and earth science, the role of observing was emphasized.

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Analysis of Middle School Students' Thinking Processes in Galileo's Free Fall Thought Experiment (갈릴레오의 자유낙하 사고실험에 대한 중학생들의 사고과정 분석)

  • Jeong, Su-In;Park, Jong-Won
    • Journal of The Korean Association For Science Education
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    • v.21 no.3
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    • pp.566-579
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    • 2001
  • The purpose of this study was to investigate students' actual thinking processes during conceptual change about free fall. To do this, middle school students were made an interview designed based on a teaching model using thought experiment. From the study, it was found that strategy for generating cognitive conflict by suggesting opposite views was not effective. However, many students changed their prior conceptions when new explanatory hypothesis, which explained why heavy object and light object fall equally, was introduced. And finally, even though students realized that the changed idea did not accord with the real world, they could easily solve that problem by observing demonstration designed to show the effect of air resistance.

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Examination of the Effect of Employee Value Proposition(EVP) on Job Satisfaction and Organizational Loyalty (호텔기업의 제안된 직원가치(EVP: Employee Value Proposition), 직무만족도, 조직충성도의 구조적 관계에 대한 연구)

  • Kim, Hye-Lin;Kwon, Na-Kyung
    • The Journal of the Korea Contents Association
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    • v.13 no.7
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    • pp.369-378
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    • 2013
  • The purpose of this study is to examine the effect of Employee Value Proposition (EVP) on job satisfaction and organizational loyalty. As a result, the study clarifies the hotel's EVP system in addition to examining the relationships among EVP, job satisfaction, and organizational loyalty by generating theocratical and practical application related to those behaviors. Using a sample drawn from full-time workers in hotel, total 379 participants were included in the analysis. The study tested the hypothesis by using a structural equation modeling approach. The analysis results show that EVP has significant influence on job satisfaction and organizational behavior. However, job satisfaction does not influence organizational loyalty.

A Study on Analysis of Elementary School Students' Perception on Science Classes Using Abductive Strategies (귀추전략을 이용한 과학수업에 대한 초등학생들의 인식 분석)

  • KIM, Hee-Yeon;KANG, Beodeul;YOO, Pyoung-Kil
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.5
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    • pp.1492-1507
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    • 2016
  • The purpose of this study was to analyze elementary students' perception on science classes using abductive strategies. The participants were composed of 21 students(10 boys, 11 girls) from K Elementary School in Busan Metropolitan City. They were asked for questionnaires developed by researchers after 20 times of reframed science lessons using abductive strategies. The results were as follows. First, the science classes using abductive strategies were effective to improve students' interest(ave.=4.19) on science. Second, the analysis results on questionnaires asking utility of the classes showed the students' positive reactions to science lessons using abductive strategies. It was thought that the classes had a positive effect on all components of utility, i.e., overall science(4.48), generating hypothesis(4.19), conceptual understanding(4.19), and meta-cognition(3.76). Third, students perceived positively improvement on the science classes. The components of improvement, i.e., creativity(4.19), concentration(4.29), transfer(3.76), comprehension(4.29) were perceived positively by students. Fourth, students' satisfaction on the sciences classes showed ave.=3.71. Last, students expressed satisfaction on the science classes using abductive strategies and experienced a change of thinking about attitude toward science.

Multimedia Scaffolding Tools to Help Children's Scientific Investigation in a Virtual Field (가상 필드에서 초등학생들의 과학적 탐구를 도와주는 멀티미디어 보조 도구)

  • Choo Yongjoo;Park Kyoung Shin
    • The KIPS Transactions:PartB
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    • v.12B no.2 s.98
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    • pp.143-150
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    • 2005
  • The Field is a simulated virtual environment specifically designed to assist elementary students learn the basic scientific inquiry skills such as observation, data collection, and generating and verifying hypothesis. Over the last four years, the Field has been used to teach inquiry learning in the context of mathematics and science in an elementary school. During the studies, it was observed that students suffered from problems in navigation, wayfinding, and data collection. First, this papers discusses the problems and the technical aids we have iteratively developed to address these issues. We will then discuss the impact of the technical aids on the student's behaviors.

Exploration and Exploitation in Supply Chain Management Practices, Competitive Advantage, Firm Performance, and Boundary Conditions (양면적 공급사슬관리 활동과 경쟁우위)

  • Huh, Moon-Goo
    • Asia-Pacific Journal of Business
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    • v.11 no.3
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    • pp.107-122
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    • 2020
  • Purpose - This paper investigates the relations among exploratory and exploitative supply chain management practices, competitive advantage, and firm performance. Design/methodology/approach - This study takes a hypothesis-generating study to capture the tradeoffs between exploration and exploitation and develops some hypotheses which involve the relations among SCM practices, competitive advantage, and short-term and long-term performance. Findings - Exploitative SCM practices have more positive effects on short-term performance rather than long-term performance, whereas exploratory SCM activities affect long-term performance. Further competitive strategy, environmental dynamism, and organizational slack moderates the relationship between SCM and performance. Exploitative SCM is more desirable when a firm uses low cost strategy, lacks slack resources, and faces stable environment, while exploratory SCM is more effective when a firm employs differentiation strategy, has slack resources, and confront dynamic environment. Research implications or Originality - In order to understand the performance effects of a variety of SCM practices, we should distinguish between exploitative and exploratory SCM activities. Further the relationship between SCM and performance may differ depending upon some contingent variables such as external environment, competitive strategy and organizational slack.

Cases and Features of Abductive Inference Conducted by a Young Child to Explain Natural Phenomena in Everyday Life

  • Joung, Yong-Jae
    • Journal of The Korean Association For Science Education
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    • v.28 no.3
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    • pp.197-210
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    • 2008
  • The purpose of this study is to explore the cases and features of the abductive inference used by young children when trying to explain natural phenomena in everyday life. From observing a 5-year-old's daily activities with his family, and analyzing the data according to the criterion extracted from the form of abductive inference described by C. S. Peirce, a few cases where the child used abductive inferences to explain natural phenomena were found. The abductive inferences in the cases were conducted: (a) based on figural resemblance and behavioral resemblance (b) under the influence by individual belief and communal belief, then (c) resulted in new categorization accompanied by over generalization. Such features of the abductive inference showed the 'double faces'; sometimes encourages and sometimes discourages children's generating better scientific hypotheses and explanations. These results suggest that even young children use abductive inference to explain doubtful natural phenomena in everyday life, although we need to consider carefully with the double aspects of the features of abductive inference for the practical applications to the fields of science education. Finally, several suggestions and following studies for science education are proposed.

Drawing Elements of Inquiry in Field Geology and Analyzing Field Geology Education in Previous Studies (야외 지질학 탐구 요소 추출 및 지질 답사 교육 문헌 분석)

  • Jung, Chanmi;Shin, Donghee
    • Journal of The Korean Association For Science Education
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    • v.37 no.3
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    • pp.465-481
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    • 2017
  • This study is a research synthesis analyzing how field geology education is conducted in domestic and foreign countries in the recent 20 years and how it reflects the characteristics of authentic geologic inquiry. For these purposes, we first drew five elements of inquiry in field geology (observation, representation, abductive reasoning, spatial thinking, and diachronic thinking) considering the field geologists' actual research method as well as its pedagogical significance in science education. We developed analysis criteria for field geology education. The 53 cases were analyzed based on each element of inquiry in field geology and its sub-elements, and also the tendency of overall elements. As a result, observation and representation were included in most cases, but there appeared less frequency in order of abductive reasoning, spatial thinking, and diachronic thinking. For observation, the ratio of purposive observation and autonomous observation is high. For representation, both visualizing and linguistic type of representation and free-form representation appear frequently. For abductive reasoning, the step of generating hypothesis is often included and the hypothesis tends to be about the geological formatting process. For spatial thinking, type of self-location and perception of the spatial configuration of the structure appear at a high rate. For diachronic thinking, type of stratigraphic sequence is the most frequent. The proportions of the cases including three or more elements of inquiry in field geology consist 87% of the total. We suggested implications for improving geological fieldwork as authentic science inquiry in the future.