• School Mathematics
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• v.18 no.4
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• pp.819-838
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• 2016

This research analyzed proportional reasoning abilities of the 5th grade students who learned only the basis of ratio and rate and 6th grade students who also learned proportion and cross product strategy. Data were collected through the proportional reasoning tests and the interviews, and then the achievement of the students and their proportional reasoning strategies were analyzed. In the light of such analytical results, the conclusions are as follows. Firstly, there is not much difference between 5th and 6th grade students in the achievement scores. Secondly, both 5th and 6th graders are less familiar with the geometric, qualitative and comparisons tasks than the other tasks. Thirdly, not only 5th graders but also 6th graders used informal strategies much more than the formal strategy. Fourthly, some students can't come up with other strategies than the cross product strategy. Finally, many students have difficulties in discerning proportional situation and non-proportional situations. This study provided suggestions for improving teaching proportional reasoning in elementary schools in Korea as follows: focusing on letting students use their informal strategies fluently in geometric, qualitative, and comparisons tasks as well as algebraic, quantitative, and missing value tasks focusing on the concept of ratio and proportion instead of enforcing the formal strategy.

• Journal of Korea Water Resources Association
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• v.45 no.1
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• pp.91-99
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• 2012

In this study, it was proposed that extension techniques of 8 day interval recorded stream-flow data which has been produced at the mouth of unit watersheds for TMDLs to daily one. The concept of this method was that the missing data at partial recording station was filled by using the daily data at a nearby, hydrologically similar streamgaging station. First, same day stream-flow was extracted from the daily stream-flow. Then, the extension equation was developed based on the sample data when the same day stream-flow from daily data and the partially recorded stream-flow was deeply related each other. The missing data was interpolated or extrapolated by the equation. Especially the maintenance of variance extension (MOVE) technique was used to derive the equation and was validated. Finally the 8-day interval recorded stream-flow at the mouth of unit watersheds in Han River Basin for TMDLs was extended to continuously daily data by using the method proposed in this study. And the low flow at each unit watershed was evaluated according to the flow-duration curve.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.2
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• pp.209-222
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• 2011

Missing anterior teeth can be replaced using any of a number of methods. Patients may choose to replace missing teeth with a prosthesis that is either removable, fixed, or retained with implants. For patients faced with financial, anatomical, and/or esthetic limitations, the edentulous region can be restored successfully and esthetically with a properly designed and fabricated rotational path RPD. The rotational path RPD is a partial removable dental prosthesis that incorporates a curved, arcuate, or variable path of placement allowing one or more of the rigid components of the framework to gain access to and engage an undercut area. The rigid retainer must gain access to the infrabulge portion of the tooth by rotating into place. Either a minor connector or proximal plate provides retention through its intimate contact with a proximal tooth surface. A specially designed dovetails or asymmetric rest seats provides support and embracing effects. Correctly designed and fabricated rotational path RPD can provide improved esthetics, cleanliness, and retention. But rotational path RPDs are technique sensitive since the rotational path RPD has little margin of laboratory error that rigid retainers cannot be adjusted like conventional clasps can, RPD framework must be remade once the retention is lost. The sufficient understanding of the concept for the rotational path RPD is required for clinically successful treatment. This clinical report describes in detail the theoretical, laboratory considerations and the treatment of a patient with an anterior maxillary edentulous area treated by an AP path rotational RPD that had a difficulty in long term maintenance and describes another clinical case in which more reasonable treatment procedures were approached after analyzing the former case.

• Archives of design research
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• v.17 no.2
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• pp.479-486
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• 2004

We need to seek after new direction and order of design that puts more value on the spirits and culture of human beings in the 21st century, creating a new, all-inclusive value in which individual human being, the society and the environment can co-exist in a peaceful relationship by overcoming the materialistic, analytical, competitive, and differentiated values of traditional industrial society. The aim of this study, then, is to present a new method of design that can meet the demands of the 21st century in a civic age of information, knowledge and culture, by focusing on Monistic ideals derived from a deeply rooted Oriental philosophy. The concept of Monism is embodied by a mind set that treasures the benefit to others over rewards to the self, puts more importance on the spiritual life hidden behind physical phenomena, thinks more of what lacks than what exceeds, elevates the mind over the body, and seeks after beauty via a total harmony of balance and development that can be feasible only by combining all these elements. Ultimately, the new design principle based on the Monism consists of three basic elements: (1) identification of the subject and the object between things under the perception that all things are one (Unification); (2) the ability that helps things exist with appropriate beauty maintaining balance and stability (Harmony); and (3) the attitude of sharing to maintain sustainable vitality by filling up what lacks or is missing in a whole(Change).

• The korean journal of orthodontics
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• v.24 no.4 s.47
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• pp.759-772
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• 1994

Orthodontists have experienced the treatment of cases with three lower incisors. Occasionally a lower incisor was either congenitally missing or so seriously damaged by injury or disease that its removal presented the best prospect for the patient. Sometimes the intentional extraction of a lower incisor is needed to produce enhanced functional and esthetic results with minimal orthodontic manipulation. Such cases have unfavorable anterior tooth size discrepancies and present difficulties in achieving good occlusal results. However such difficulties can be overcome by the sensible diagnosis and treatment plan. Three different cases are presented and the conclusions are listed. 1. It is important for orthodontist who tries to treat three lower incisor cases to measure and calculate accurately the degree of deviation of tooth size and morphology and the anterior tooth size ratio. 2. A diagnostic setup model should be made to determine whether the incisor extraction is appropriate and space closure is needed or not. It is the best way to be sure that the occlusal results, including overbite and overjet, will be acceptable and how far the degree of midline deviation is. It also shows the amount of interproximal reduction to achieve an acceptable occlusal result. 3. The class I relationship between the upper canine and the lower one must be obtained to establish the canine rise during eccentric movement by the concept of mutually protective occlusion. It also helps to maintain the stable occlusal result.

• Animal cells and systems
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• v.6 no.1
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• pp.13-18
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• 2002

Phylogenetic relationships of Korean Acidiella species were tested using mitochondrial 16S ribosomal RNA gene sequences. We used 16 published sequences as outgroup, and 10 new sequences for nine Korean Acidiella species as ingroup. The number of aligned sites was 1,281 bp, but 1,135 bp were used for the analysis after excluding sites with missing data or gaps. Among these 1,135 sites, 464 sites were variable and 340 were informative for parsimony analysis. Phylogenetic information was extracted from this data set using neighbor-joining, maximum likelihood and maximum parsimony methods and compared to a morphology-based phylogenetic hypothesis. Our molecular data suggest that: (1) the tribe Trypetini appears to be monophyletic even when the nine additional Acidiella species are added to our previous phylogenetic analysis; (2) all the Korean Acidiella species belong to the Trypeta group, but the genus Acidiella is not supported as monophyletic; (3) the close relationship of A. circumvaga, A. issikii, and A. sapporensis is supported; (4) the close relationship of A. pachypogon and two additional new Acidiella species is strongly supported; and (5) the possible presence of two or more cryptic species among the specimens previously identified as A. obscuripennis is suggested. Sequence data from the mitochondrial 16S rDNA allowed us to better understand the systematic status of Korean Acidiella species. They indicated that the current concept about the genus Acidiella is insufficient and needs to be refined further. This study also showed a few interesting relationships, that had not been recognized by morphological study alone. Based on this study, we were able to plan further experiments to analyze relationships within the Trypeta Group.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2000.11a
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• pp.56-58
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• 2000

Post-genomics may be defined in different ways depending on how one views the challenges after the genome. A popular view is to follow the concept of the central dogma in molecular biology, namely from genome to transcriptome to proteome. Projects are going on to analyze gene expression profiles both at the mRNA and protein levels and to catalog protein 3D structure families, which will no doubt help the understanding of information in the genome. However complete, such catalogs of genes, RNAs, and proteins only tell us about the building blocks of life. They do not tell us much about the wiring (interaction) of building blocks, which is essential for uncovering systemic functional behaviors of the cell or the organism. Thus, an alternative view of post-genomics is to go up from the molecular level to the cellular level, and to understand, what I call, the "interactome"or a complete picture of molecular interactions in the cell. KEGG (http://www.genome.ad.jp/kegg/) is our attempt to computerize current knowledge on various cellular processes as a collection of "generalized"protein-protein interaction networks, to develop new graph-based algorithms for predicting such networks from the genome information, and to actually reconstruct the interactomes for all the completely sequenced genomes and some partial genomes. During the reconstruction process, it becomes readily apparent that certain pathways and molecular complexes are present or absent in each organism, indicating modular structures of the interactome. In addition, the reconstruction uncovers missing components in an otherwise complete pathway or complex, which may result from misannotation of the genome or misrepresentation of the KEGG pathway. When combined with additional experimental data on protein-protein interactions, such as by yeast two-hybrid systems, the reconstruction possibly uncovers unknown partners for a particular pathway or complex. Thus, the reconstruction is tightly coupled with the annotation of individual genes, which is maintained in the GENES database in KEGG. We are also trying to expand our literature surrey to include in the GENES database most up-to-date information about gene functions.

• Journal of the Korean School Mathematics Society
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• v.16 no.4
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• pp.719-743
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• 2013

Proportional reasoning is considered as a difficult concept to most elementary school students and might be connect to functional thinking, algebraic thinking, and mathematical thinking later. The purpose of this study is to analyze the sixth graders' development level of proportional reasoning so that children's problem solving processes on different proportional problem items were investigated in a way how the problem type of proportion and the degree of ill-structured affect to their levels. Results showed that the greater part of participants solved problems on the level of proportional reasoning and various development levels according to type of problem. In addition, they showed highly the level of transition and proportional reasoning on missing value problems rather than numerical comparison problems.

• Journal of Korean Society for Quality Management
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• v.35 no.3
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• pp.37-46
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• 2007

Our society is increasingly dependent on the Internet, and this trend will be accelerating in the ear of All-IP convergence. As the core infrastructure of the All-IP convergence, the next generation Internet should enable end-to-end Quality of Service(e2e QoS). For that purpose, major international standardization institutes such as ITU(International Telecommunication Union) and IETF(Internet Engineering Task Force) are building the concept and architecture of the Next Generation Network(NGN). However, these institutes focus only on technical issues, and leave many business/policy-oriented challenges unresolved. For example, the standards raised by ITU assume that the entire service delivery process for e2e QoS services is perfectly working. But required is a standardized business interface and process for seamless inter-operations across many stakeholders including ISPs(Internet Service Providers), CPs(Content Providers), so on. On the other hand, TMF(TeleManagement Forum) and QuEST(Quality Excellence for Suppliers of Telecommunication) Forum, global consortiums of telecom operators and vendors, present sets of interface rules and process which playa crucial role as de facto standards: for example, NGOSS/eTOM and TL9000 authorization system. However, these standards focus on telephone services, and provide little principle for the next generation Internet. Our study seeks a way to combine these two strains for a successful implementation of NGN. In particular, we find a missing link in the NGN architecture and the elements that could be complemented with the help of NGOSS/eTOM and TL9000. Finally, presented is a strategic direction that our standardization policy should purse in order to reinforce our global leadership for the next generation Internet.

• Environmental and Resource Economics Review
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• v.12 no.2
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• pp.347-382
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• 2003

The paper presents available options that Korea can adopt in an effort to promote eco-industrial development in a near future. What is missing and the reasons why Korea is behind the other countries in the area are: 1) Lack of holistic view and the integrated approach toward economy and environment in policy implementation, 2) Lack of understanding, among entrepreneurs, of the concept of productivity per input resource, and the fact that not only labor and capital productivity but also the total productivity enhancement is vital for industry's competitive edge; There has been no driving force in the market to develop economies of system integration to turn industrial wastes to valuable input resources, 3) Unsupportive regulatory system regarding the trade of by products, and 4) Lack of financing and incentive mechanism. 5) Lack of information forum. Regulatory reform should be taken for the direction that in effect increase the price of disposal and motivate firms to seek symbiotic relationship with other firms, and facilitate trade by-product between firms. Financing and incentive mechanism should be introduced in order for the industry to find easy access to the opportunities for organizing the network to transform wastes in negative value to the value added resources. Also information network should be established to provide a market for by-product exchange and public education to improve industry's environmental performance.