• The KIPS Transactions:PartB
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• v.15B no.2
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• pp.147-158
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• 2008

Fuzzy Cognitive Map (FCM) and Bayesian Belief Network (BBN) are two major frameworks for modeling, representing and reasoning about causal knowledge. Despite their extensive use in causal knowledge engineering, there is no reported work which compares their respective roles. This paper aims to fill the gap by providing a qualitative comparison of the two frameworks through a systematic analysis based on some inherent features of the frameworks. We proposed a set of comparison criteria which covers the entire process of causal knowledge engineering, including modeling, representation, and reasoning. These criteria are usability, expressiveness, reasoning capability, formality, and soundness. The results of comparison have revealed some important facts about the characteristics of FCM and BBN, which will help to determine how FCM and BBN should be used, with respect to each other, in causal knowledge engineering.

• Journal of The Korean Association of Information Education
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• v.20 no.1
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• pp.101-108
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• 2016

Most of a courseware evaluated negatively by short of instructional strategy to improve learning effects. Designing a courseware is a time-taking and challenging task. Therefore, a method is required that helps to easily design courseware that is effective to learning. This study proposed a method for designing and management courseware by utilizing a metacognitive strategy. We made a design the coursewase efficiently using concrete instructional model frameworks as metacognitive stragety and tried to improve the quality of courseware for learning effects. We applied our proposed method to teacher's college students in Korea who were taking the "Courseware Development" course. After analyzing it's effects, the responds can design courseware easily and monitor the design direction while their designing. Also, they can design the courseware systematically and implement detail instructional strategy by using concrete instruction model frameworks as metacognitive strategy. However, they were not easy to develop concrete instructional model frameworks at first and we need sharing it among the designers.

• Journal of Technologic Dentistry
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• v.42 no.2
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• pp.81-89
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• 2020

Purpose: This in vitro study was conducted to evaluate the marginal and internal fit of three-unit Co-Cr frameworks fabricated by computer-aided metal milling and direct metal laser sintering(DMLS) systems in comparison to conventional casting method. Methods: Three-unit Co-Cr frameworks were fabricated by conventional wax up with casting(CWC), computer-aided metal milling(MM) and direct metal laser sintering(DMLS)(n=10 each). The marginal and internal fit of specimens were examined using a light-body silicone impression material. The thickness of light-body silicone was measured at eight reference points each, divided in the mesio distal and bucco lingual directions. All measurements were conducted by a stereomicroscope. Digital photos were taken at 150× magnification and then analyzed using a measurement software. The Kruskal-Wallis test and Bonferroni correction were used for analyzing the results. Results: The mean(SD) is ㎛ for fabrication methods, the mean marginal fit were recorded respectively, DMLS 39(27), followed by CWC 63(38), MM 220(128). and the mean internal fit CWC 95(47), DMLS 116(49), MM 210(152). In addition, the largest gap was found in the occlusal surface area among the internal measurement areas of all groups. Conclusion: As a result, the direct metal laser sintering method showed better marginal and internal fit than the metal milling method. The marginal and internal fit were statistically different according to the three fabrication methods(p<0.001). Except the MM group, the marginal fit of the CWC and DMLS groups was below the clinical standard of 120 ㎛. Based on the results of this study, it can be applied to clinical use in the future.

• Korea journal of population studies
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• v.24 no.2
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• pp.47-78
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• 2001

The primary purpose of this paper is to critically examine the theoretical and methodological issues in the study of generations. The issues include: 1) the concept of generation: 2) the basis of generational formation: 3) internal differentiation of generations: 4) the boundary problems of generations: 4) the boundary problems of generations: and 5) generational differences and generational conflict. From the investigation of these issues, two conclusions are drawn. Firstly, Mannheim's basic concepts and theoretical frameworks are very useful to understand and explain the social movements and sociocultural changes. Secondly, however, further elaboration and modification of the several concepts and frameworks are needed to deal with the problems of generations in general which are not directly connected to social movements. Several points are suggested to elaborate Mannheim's frameworks, which include the reconceptualization of generation, and introducing the concepts of “generation sects” and “manifest-latent generational conflicts”.

• Transactions of the Korean hydrogen and new energy society
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• v.15 no.2
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• pp.108-118
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• 2004

To find out rational design and synthetic strategies toward efficient hydrogen storage materials, molecular modeling and quantum mechanical studies have been carried out on the MOFs(Metal-Organic Frameworks) having various organic linkers and nanocube frameworks. The calculation results about the free volume ratio, surface area, and electron density variation of the frameworks indicated that the capacity of the hydrogen storage of MOFs was largely dependent on the specific surface area and electron localization around benzene ring rather than the free volume of MOFs. The prediction of the modeling study could be supported by the hydrogen adsorption experiments using IRMOF-1 and -3, which showed more enhanced hydrogen storage capacities of IRMOF-3 compared with the IRMOF-1's at both experimental conditions, 77K, ∠ $H_2$ 1 atm and ambient temperature, ∠ $H_2$ 35 atm.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.2
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• pp.156-171
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• 2002

The purpose of this study was to measure and compare the strains produced by screw-tightening implant frameworks fabricated by aye different fabrication methods; (1) one-piece cast using plastic sleeve, (2) one-piece cast using gold cylinder, (3) laser welding, (4) soldering, and (5) electrical discharge machining, and also to measure and compare the strains produced when the order of screw tightening was changed A research model incorporating eighteen strain gages was made to measure the fit of implant frameworks in three dimensions. Three implants aligned in an arc were fixed on the top ends of the L-shape aluminum bars of the research model, and standard abutments were joined to the implants with abutment screws. Five types of implant framework were placed on the abutments and screwed by a torque wrench using 10 Ncm. Under the conditions of this study, the following conclusions were drawn: 1. The electrical discharge machining group showed the smallest magnitude of strain, followed by the soldering group, the laser welding group, the one-piece cast group using gold cylinder, and the one-piece cast group using plastic sleeve. However, among the magnitude of strain for the remaining groups except the electrical discharge machining group, there were not significant differences. 2. When the order of screw tightening was changed, there were not significant differences in the magnitude of strain. 3. In comparison with the electrical discharge machining group, the laser welding group and the one-piece cast groups showed greater horizontal distortion and the soldering group showed greater horizontal and vertical distortion.

• Journal of the Korea Society of Computer and Information
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• v.13 no.1
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• pp.161-167
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• 2008

As the authentication and the integrity methods based on the hash chain are popular, several certificate status validation methods based on the same function are proposd at the moment. In NOVOMODO, a CA generates and releases the hash value to each user. In Jianying Zhou's framework and Jong-Phil Yang's framework, a user generates and releases the hash value to verifier. Therefore, the CA loads are distributed to each user. However, these frameworks are based on the assumption that the CA's secret key is not lost or compromised and the certificates issued by the CA are error-free. Therefore, these frameworks are not suitable in real PKI environments. In this paper, as one hash value generated by CA is included in the user's certificate in addition, the certificate revocation published by CA using that value can be managed. The hash value included in user's certificate is the same for all users. The computation costs, the storage amounts and the release costs are small in the CA. And we modify the procedure for the signature and its validation in Jong-Phil Yang's framework. Our solution is more suitable than those frameworks in real PKI environments.

• The Journal of Society for e-Business Studies
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• v.12 no.2
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• pp.195-217
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• 2007

B2B registries provide spaces to register and retrieve information which is necessary to support B2B transactions among business partners or potential business partners. Business process specifications are one of important contents in B2B registries, and there is high complexity of representation due to complex and dynamic characteristics of business processes. Also, currently there exist several competing specification frameworks such as ebXML BPSS, WSBPEL, BPMN, and so on. This paper proposes a metadata schema to register business process specifications which are represented by different specification frameworks. The proposed schema has extensibility to register business process specifications which are represented by various different specification frameworks. Also, it extends reuse level from whole business specification processes to their components. To show the usefulness of the proposed schema, this paper demonstrates metadata extraction from business process specifications which are represented by two representative XML-based business process specification languages, ebXML BPSS and WSBPEL.

• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3777-3787
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• 2012

Three kinds of 3D isomorphous and isostructural coordination polymers, namely, $\{[Ln_2(PDA)_3(H_2O)_3]{\cdot}0.25H_2O\}_{\infty}$ (Ln = La(1), Sm(2), and Gd(3)) ($PDA^{2-}$ = pyridine-2,6-dicarboxylate anion) have been synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectroscopy, thermal analyses and single crystal X-ray diffraction. In these MOFs, Ln(III) centers adopt eight-coordinated and nine-coordinated with the $N_1O_7$ and $N_2O_7$ donor sets to construct distorted trianglar dodecahedron geometry and tricapped trigonal prism configurations, respectively. Based on the building block of tetranuclear homometallic $Ln_4C_4O_8$ unit (16-membered ring), 1-3 are connected into highly ordered 2D sheets via O-C-O linkers and further constructed into 3D architectures through hydrogen bonds. Crystallographic parameters suggest that the lanthanide contraction effect exist in these coordination polymers. Luminescent properties of the lanthanide-based MOFs (metal-organic frameworks) have been measured at room temperature, which reveal that they presenting ionselective characters toward certain metals, such as $Mg^{2+}$, $Cd^{2+}$ and $Pb^{2+}$ ions.

• Journal of The Korean Association For Science Education
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• v.23 no.5
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• pp.484-493
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• 2003

This case study exemplifies science classroom observation and analysis. Data from two-day classroom observation, pre- and post-instruction interviews with the teacher and instructional materials were used to analyse the features of a science classroom. A teacher's classroom practices were examined in terms of the following six categories: (1)curriculum and science content, (2)teaching and learning methods, (3) teacher' s knowledge about learners, (4)classroom environment, (5)assessment, and (6)teacher's efforts for professional development. The teacher in this case study not only improved his own classroom practices, but also took an active role in teachers' in-service education to share his practical knowledge with others. Implications that valid evaluation(or observation) frameworks of classroom practices have on teacher education and teachers' inservice education are also discussed. These evaluation frameworks should provide teachers with a vision of highly accomplished practices.