• Title/Summary/Keyword: Logical model

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Exploring Pre-Service Earth Science Teachers' Understandings of Computational Thinking (지구과학 예비교사들의 컴퓨팅 사고에 대한 인식 탐색)

  • Young Shin Park;Ki Rak Park
    • Journal of the Korean earth science society
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    • v.45 no.3
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    • pp.260-276
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    • 2024
  • The purpose of this study is to explore whether pre-service teachers majoring in earth science improve their perception of computational thinking through STEAM classes focused on engineering-based wave power plants. The STEAM class involved designing the most efficient wave power plant model. The survey on computational thinking practices, developed from previous research, was administered to 15 Earth science pre-service teachers to gauge their understanding of computational thinking. Each group developed an efficient wave power plant model based on the scientific principal of turbine operation using waves. The activities included problem recognition (problem solving), coding (coding and programming), creating a wave power plant model using a 3D printer (design and create model), and evaluating the output to correct errors (debugging). The pre-service teachers showed a high level of recognition of computational thinking practices, particularly in "logical thinking," with the top five practices out of 14 averaging five points each. However, participants lacked a clear understanding of certain computational thinking practices such as abstraction, problem decomposition, and using bid data, with their comprehension of these decreasing after the STEAM lesson. Although there was a significant reduction in the misconception that computational thinking is "playing online games" (from 4.06 to 0.86), some participants still equated it with "thinking like a computer" and "using a computer to do calculations". The study found slight improvements in "problem solving" (3.73 to 4.33), "pattern recognition" (3.53 to 3.66), and "best tool selection" (4.26 to 4.66). To enhance computational thinking skills, a practice-oriented curriculum should be offered. Additional STEAM classes on diverse topics could lead to a significant improvement in computational thinking practices. Therefore, establishing an educational curriculum for multisituational learning is essential.

Determinants and Processes of IT Consolidation: A Case Study of Korean Conglomerates (IT 통합의 결정 요인과 과정: 국내 대기업들에 대한 사례 연구)

  • Zo, Hang-Jung;Song, Chan-Hoo;Han, Seung-Hun
    • Information Systems Review
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    • v.10 no.3
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    • pp.223-255
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    • 2008
  • This study explores the determinants and processes of IT consolidation of Korean conglomerates. Through an extensive analysis of cases, this study identifies the drivers, benefits and critical success factors of IT consolidation, and observes the transition of vision for the IT service subsidiaries in the conglomerates. The results show that most firms in this analysis have completed the organizational, physical, and logical consolidation of their IT resources, and currently some of them are preparing for the next stage of IT consolidation such as rational consolidation and virtualization. It is also found that the strategic factor was one of the most significant determinants in consolidating IT resources which leaded the transition of vision of the IT service firms in the conglomerates from "cost center" to "profit center". The results of this study can provide a fundamental and empirical basis for building a theory of IT consolidation, and be used as a valuable benchmarking model for the organizations which consider starting a project of IT consolidation.

Gamma Knife Radiosurgery for Intracranial Meningioma (두개강내 수막종에 대한 감마나이프 방사선수술)

  • Shim, Kyu Won;Chang, Jong Hee;Choi, Jae Young;Chang, Jin Woo;Park, Yong Gou;Chung, Sang Sup
    • Journal of Korean Neurosurgical Society
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    • v.30 no.11
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    • pp.1263-1270
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    • 2001
  • Objective : To analyze the radiosurgical results of intracranial meningiomas after Gamma Knife radiosurgery (GKS) and to assess the possible factors related to the outcome and complications in treating meningiomas. Patients and Methods : We retrospectively reviewed the clinical and radiological data in 179 patients(194 lesions) treated with GKS for intracranial meningiomas between May 1992 and October 2000. Radiosurgical responses were categorized as shrinkage, stasis and enlargement, and we defined the shrunken and static group as a radio-logical control. A Cox proportional hazards model was used to evaluate the correlation between the radiosurgical outcomes and various factors such as location and size of tumor, age and gender of patients, relation to venous sinus, pre-GKS degree of edema, treatment modality, radiosurgical parameters, and pathologic findings. Results : Patients were grouped into skull base meningiomas(57.7%), non-skull base tumor including convexity, parasagittal, and falx meningiomas(37.1%), and others(5.2%) according to the location of tumors. The mean maximum dose and the margin dose of tumor was 30.0Gy(19-45Gy) and 15.1Gy(9.5-24.5Gy), respectively. The mean volume of the tumors was 9.4cc(0.003-45.0cc). The radiologic control rate was 97.1%. The radiation induced imaging change with or without neurologic deficit was the most common complication(23.6%). There were seen mostly in convexity, parasagittal, and falx meningiomas which were deeply embedded in cortex. Conclusion : GKS for intracranial meningioma seems to be safe and effective treatments. However, GKS should be considered very cautiously in non-skull base tumor such as convexity, parasagittal, or falx meningiomas with regards to patient's age and general condition, size and location of tumor, pattern of embedding into cortex, presenting symptoms and patient's preference.

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A Study on the Concept of Digital Environmental Rights and Reinforcement of Information Subject (디지털 환경권 개념 정립과 정보교과 교육 강화에 대한 연구)

  • Yoo, Jiyeon
    • Journal of The Korean Association of Information Education
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    • v.24 no.2
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    • pp.189-199
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    • 2020
  • This study aims to emphasize the necessity of strengthening the information subject through the introduction of a new concept of rights called 'digital environmental rights' and proposes an improvement in the educational composition model of the information culture section in the information subject. Through the introduction of the concept of digital environmental rights, we intend to provide a logical basis for making the information subject a required subject. In addition, we intend to enhance the competencies required for living in a digital environment by improving the structure of the information culture section in the information subject. As a study on this, the logic of the concept of rights required in the digital environment is analyzed and the concept of digital environmental rights applied to it is established. Furthermore, by analyzing relevant curricula in major countries, including the United States, Australia, and Japan, which provide the main basis for digital environmental rights, an improvement plan for the educational composition in the information and culture education sector is formulated. The results of the study are as follows: First, digital environment rights are 'rights to enjoy a pleasant and safe digital environment'. Second, the components of digital environmental rights include rights for the environment (cyberethics), rights of the environment (cybersafety), and rights about the environment (cybersecurity). Third, in the major countries studied various educational structures are being implemented with regard to information-related education contents on the digital citizenship, code ethics, and new technology security.

A Comparative Study on the Logic Structure of Myeongri Old Law and New Law (명리학 고법과 신법의 논리구조 비교연구)

  • Na, Hyeok-Jin;Jung, Kyeong-Hwa
    • Industry Promotion Research
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    • v.5 no.3
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    • pp.61-71
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    • 2020
  • The purpose of this paper is to reaffirm the logical framework of the saju analysis method by recreating the saju model of old-law to study and organize the theories of frame in old-law Myeongri, and then by organizing and comparing the logic structure of the saju analysis method of new-law and old-law. Some believe that Myeongri Theory first appeared in the world in the Warring States Period when they were active with Gwigokja and Naknokja as origin, while others believe that it was origin that "Okjokyeong" was written by Kwak-Bak of Eastern Jin after a while. Since then, Myeongri Theory, which had been organized by Won-Cheongang and Yi-Heojung, has undergone a major transformation since reaching the Song Dynasty Seo-Japyeong. Based on this point, the Myeongri Theory of the previous generation is called the Old-law, and the subsequent theory is called the New-law. The changes in the logic structure of the old-law and the new-law leave a big difference and disconnect between those. But comparative studies have confirmed that the philosophy and logic structure due to natural laws that have not changed much such as the symbolic system of nature called Yinyang & five elements and Cheongan-jiji, the idea of a heavenly response projected in the Three Wonders of heaven, earth and human, and the concept of generation and time in the position of year-month-day-time.

Improvement of the Calculation Standard for Prolongation cost of Long-term Continuing Contracts Construction Project (장기계속계약공사의 공기연장 추가간접비 산정 개선방안)

  • Jeong, Kichang;Lee, Jaeseob
    • Korean Journal of Construction Engineering and Management
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    • v.18 no.2
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    • pp.30-37
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    • 2017
  • In Korea, additional indirect costs generated from the time period extension of public construction projects have been studied. Practical claims against such costs are increasing. There are no clear criteria for calculating the delay cost caused by the extension, and thus calculation methods differ across entities. Logical valid calculation methods have also not been researched. Further, there are no Korean studies on the additional indirect cost caused by a suspension in a public construction project on a long-term continuing contract. The purpose of this research is to propose a method of calculating the indirect cost incurred by construction time extension that reflects the characteristics of Korean public construction projects. The cost patterns generated during construction periods were analyzed, and then the current criteria of calculating the indirect costs caused by the extension were examined. Following this, actual conditions and practices in the field were surveyed and the current calculation method was applied to a model case to compare the actual cost and that determined from the current calculation method. Issues with the current method were identified by this comparison. Based on this, this research proposes a method of calculating the total actual cost caused by a suspension in a public construction project that is appropriate for calculating the additional indirect cost generated by a suspension in a public construction project on a long-term continuing contract.

Scalable RDFS Reasoning using Logic Programming Approach in a Single Machine (단일머신 환경에서의 논리적 프로그래밍 방식 기반 대용량 RDFS 추론 기법)

  • Jagvaral, Batselem;Kim, Jemin;Lee, Wan-Gon;Park, Young-Tack
    • Journal of KIISE
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    • v.41 no.10
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    • pp.762-773
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    • 2014
  • As the web of data is increasingly producing large RDFS datasets, it becomes essential in building scalable reasoning engines over large triples. There have been many researches used expensive distributed framework, such as Hadoop, to reason over large RDFS triples. However, in many cases we are required to handle millions of triples. In such cases, it is not necessary to deploy expensive distributed systems because logic program based reasoners in a single machine can produce similar reasoning performances with that of distributed reasoner using Hadoop. In this paper, we propose a scalable RDFS reasoner using logical programming methods in a single machine and compare our empirical results with that of distributed systems. We show that our logic programming based reasoner using a single machine performs as similar as expensive distributed reasoner does up to 200 million RDFS triples. In addition, we designed a meta data structure by decomposing the ontology triples into separate sectors. Instead of loading all the triples into a single model, we selected an appropriate subset of the triples for each ontology reasoning rule. Unification makes it easy to handle conjunctive queries for RDFS schema reasoning, therefore, we have designed and implemented RDFS axioms using logic programming unifications and efficient conjunctive query handling mechanisms. The throughputs of our approach reached to 166K Triples/sec over LUBM1500 with 200 million triples. It is comparable to that of WebPIE, distributed reasoner using Hadoop and Map Reduce, which performs 185K Triples/sec. We show that it is unnecessary to use the distributed system up to 200 million triples and the performance of logic programming based reasoner in a single machine becomes comparable with that of expensive distributed reasoner which employs Hadoop framework.

Comparison of Brain Uptakes for Brain Drug Delivery Vector Synthesized by Chemical and Genetical Engineering Method (화학적 및 유전공학적으로 제조한 뇌송달 벡터의 뇌수송량 비교)

  • Kang, Young-Sook;Seo, Kyung-Hee
    • Journal of Pharmaceutical Investigation
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    • v.29 no.2
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    • pp.87-92
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    • 1999
  • Drug delivery to the brain may be achieved by producing chimeric peptide, attaching the drug to protein 'vectors' which are transported into the brain from the blood by a receptor-mediated transcytosis through the blood-brain barrier (BBB). Since the BBB expresses high concentrations of transferrin receptor, and it was reported that anti-transferrin receptor mouse monoclonal antibody (OX26) undergoes transcytosis through the BBB, it is logical to assume that a drug delivery system via transferrin receptor-mediated transcytosis is a promising strategy. In the present study, therefore, we tested feasibility of several OX26 based vectors for the brain delivery of a model drug. Avidin-based delivery vectors such as OX26-streptavidin (OX26-SA), OX26-neutralite avidin (OX26-NLA) were chemically synthesized vectors and OX26 immunoglobulin G 3 type $C_{H}3$ fusion avidin $(OX26\;IgG3C_H3-AV)$ was genetically engineered. To improve the efficiency of producing chimeric peptide, we used avidin-biotin technology. Pharmacokinetics of $[^3H]biotin$ bound to OX26-SA, OX26-NLA and $OX26\;IgG3C_H3-AV$ was determined by intravenous injection technique, and their stabilities in plasma were analyzed using HPLC. The brain delivery of $[^3H]biotin$ bound to OX26-SA, OX26-NLA and OX26\;$IgG3C_{H}3-AV$ (expressed as %ID/g brain) was $0.22{\pm}0.01$, $0.18{\pm}0.01$ and $0.25{\pm}0.09$, respectively. The areas under the plasma concentration versus time curve (AUC) for OX26-SA, OX26-NLA, $OX26\;IgG3C_H3-AV$ from time zero to 60 min were $209{\pm}10$, $195{\pm}9$, $134{\pm}29\;%ID\;min/ml$ respectively and their total clearances $(CL_{tot})$ were $1.00{\pm}0.09$, $1.08{\pm}0.07$ and $1.54{\pm}0.29\;ml/min/kg$, espectively. These results showed that these vectors possess preferable pharmaceutical (e.g., resonable stability) and pharmacokinetics (e.g., significant brain uptake and enhanced AUC) for brain delivery. Therefore, these vectors may be broadly useful in the brain delivery of drugs that are not transported into the brain to a significant extent.

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Development of a decision supporting system for forest management based on the Tabu Search heuristic algorithm (Tabu Search 휴리스틱 알고리즘을 이용한 산림경영 의사결정지원시스템 구현)

  • Park, Ji-Hoon;Won, Hyun-Kyu;Kim, Young-Hwan;Kim, Man-Pil
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.10
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    • pp.229-237
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    • 2010
  • Recently, forest management objectives become more complex and complicated, and spatial constraints were necessarily considered for ecological stability. Now forest planning is required to provide an optimized solution that is able to achieve a number of management objectives and constraints. In this study, we developed a decision supporting system based on the one of dynamic planning techniques, Tabu Search (TS) heuristic algorithm, which enable one to generate an optimized solution for given objectives and constraints. For this purpose, we analyzed the logical flow of the algorithm and designed the subsequence of processes. To develop a high-performance computing system, we examined a number of strategy to minimize execution time and workloads in each process and to maximize efficiency of using system resources. We examined two model based on the original TS algorithm and revised version of TS algorithm and compared their performance in optimization process. The results showed high performance of the developed system in providing feasible solutions for several management objectives and constraints. Moreover, the revised version of TS algorithm was appeared to be more stable for providing results with minimum variation. The developed system is expected to use for developing forest management plans in Korea.

Characteristics of Explanatory Hypothesis Formation by Anxiety Types in High School Students Cognitive Conflict about Action-Reaction Task (II) (작용 반작용 과제에서 고등학생의 인지갈등 불안유형에 따른 설명가설 형성의 특성(II))

  • Kim, Yeoun-Soo;Cho, Yeoung-Hean;Kwon, Jae-Sool
    • Journal of The Korean Association For Science Education
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    • v.25 no.3
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    • pp.400-410
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    • 2005
  • According to the cognitive conflict process model, student anxiety factor is known to have both positive and negative effects on student response behaviors in a conflict situation for conceptual change learning. However, there is little research that reveals what type of anxiety, either constructive or destructive, is related when conducting step-by-step experiments to resolve cognitive conflicts. This study attempted to learn the characteristic of explanatory hypothesis according to anxiety type after conducting five step-by-step experiments related to action and reaction concept. Results found that students who belonged to the types of 'conviction in logical misconception', 'insisting on additional variables', and 'reasonable modification' suggested explanatory hypothesis close to physical nature. On the other hand, those who showed the other five types of anxiety ('compatible predictions', 'dependence on others', 'fusion of past experience', 'lack of confidence', and 'conflict with past experience') suggested temporary supported hypothesis or simple explanatory hypothesis according to student intuition and simple observation. These results indicate that students in the above-mentioned five categories need more external interactions with instructors based on the type of anxiety related to student behavior. In addition, the results present student characteristics which instructors should be more attentive to when using step-by-step experiments to resolve cognitive conflicts.