• The Journal of Korean Academy of Prosthodontics
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• v.39 no.5
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• pp.463-476
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• 2001

Since the treatment of edentulous patients with osseointegrated implant was first introduced more than 30 years ago, implant therapy has become one of the most important dental treatment modalities today. Based on the previous experience and knowledge, $Br{\aa}nemark\;Novum^{(R)}$ protocol was introduced with the concept of simplifying surgical and prosthetic technique and reducing healing time recently. This protocol recommends the installation of three 5mm wide diameter futures in anterior mandible and the prefabricated titanium bars for superstructure fabrication. This study was designed to analyze the stress distribution at fixture and superstructure area according to changes of fixture number, diameter and superstructure materials. Four 3-dimensional finite element models were fabricated. Model 1 - 5 standard fixtures (13mm long and 3.75mm in diameter) & superstructure consisted of type IV gold alloy and resin Model 2- 3 wide diameter fixtures (13mm long and 5.0mm in diameter) & superstructure consisted of type IV gold alloy and resin Model 3-3 wide diameter fixtures (13mm long and 5.0mm in diameter) & superstructure consisted of titanium and resin Model 4-3 wide diameter fixtures (13mm long and 5.0mm in diameter) & superstructure consisted of titanium and porcelain A 150N occlusal force was applied on the 1st molar of each model in 3 directions - vertical($90^{\circ}$), horizontal($0^{\circ}$) and oblique($120^{\circ}$). After analyzing the stresses and displacements, following results were obtained. 1. There were no significant difference in stress distribution among experimental models. 2. Model 2, 3, 4 showed less amount of compressive stress than that of model 1. However, tensile stress was similar. 3. Veneer material with a high modulus of elasticity demonstrated less stress accumulation in the superstructure. Within the limites of this study, $Br{\aa}nemark\;Novum^{(R)}$ protocol demonstrated comparable biomechanical properties to conventional protocol.

• Journal of the Korean Geotechnical Society
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• v.21 no.8
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• pp.107-116
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• 2005

Generally, when the stability of the geosynthetic reinforced soil slopes is analyzed, the required tensile forces of each reinforcement layers are calculated from total reinforcement forces which are necessary to retain the equilibrium state of slip mass in which the slip surfaces are assumed to be a linear or bilinear. It is assumed that the reinforcement forces are increased or constant with depth. However, according to the instrumented field data and laboratory model test results, the maximum tensile strain of reinforcement in a reinforced soil slope is developed in a certain elevation, not a bottom of the slope. In the concept of reinforced soil, postulated failure surfaces are the traces of the position in which the reinforcement tensile forces are maximum in the layer, and the reinforcement tensile forces are related to the stress state on the postulated failure surface. Therefore, in this study, based on the distribution of normal stress on the slip surface, a new method for the evaluation of required tensile forces is suggested and a number of the instrumented field data are analyzed by newly suggested method. As a result, it is shown that the newly suggested method produces relatively accurate reinforcement tension forces.

• Journal of The Korean Association For Science Education
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• v.22 no.2
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• pp.276-285
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• 2002

In this study the concepts for science learning of physics and earth science presented in the seventh grade science textbooks for the seventh national curriculum of Korea approved by the ministry of education were analyzed in terms of the concrete and formal concept level. The parts of textbook analyzed for science learning consist of three sections in physics such as light, force, and waves, and three sections in earth science such as the structure of the earth, the substance of crust, and the movement and composition of the ocean. The analyzed results showed that the number of scientific concepts were differed from 54 to 74 in physics and from 86 to 120 in earth science depending upon publishers. In general, the concepts for science learning in the physics were found to be more in the formal level than the concrete level. However, the concepts for science learning in earth science were found to be more in the concrete level than the formal level. The analyzed results suggest that the concepts of science learning should be considered the learner's cognitive level and the sections should be disposed depending on the degree of difficulty for writing the science textbook. Therefore, it seems to be important to review carefully whether the textbook meets the object of the seventh curriculum of Korea during the process of the investigation for the science textbook.

• Journal of the Economic Geographical Society of Korea
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• v.4 no.1
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• pp.61-76
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• 2001

The purposes of this research are to examine the theoretical background and industrial policy issues with regard to building a Innovation System for encouraging industrial competitiveness and fostering regional industry in Korea. Knowledge has become the driving force of economic growth and the primary source of competitiveness in the world market. So since 1990s, Innovation Systems have been put emphasis on as new industrial development strategy in a knowledge-based economy. It can be understood that Innovation System is composed of National Innovation System(NIS) and Regional Innovation System(RIS) and interrelated the concept of clusters and networks, which are contribute to industry development throughout boosting innovation. As for the Korean industrial policy, when the former centralized policy decision making process became decentralized through the implementation of local autonomy, the role of local or state government in relation to regional industrial promotion intensified. But with the impotance of for fostering strategic industry in the region. new industrial policy issues in Korea are needed as follows; $\circled1$ Building a market-oriented support system for industrial cluster through providing the resource of innovation. $\circled2$ Establishing agency for regional industrial development. $\circled3$ Making a evolutionary vision for broader region including 2 or 3 province, $\circled4$ Fostering strategic industry which is selected in term of specialization and potential of the region. The RIS model for industry development is outlined in this paper but policy initiatives for building a RIS have to be extracted from further case studies.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.936-944
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• 2019

Submarines, which have been called an invisible force, are strategic underwater weapon systems that perform missions such as anti-surface warfare, anti-submarine warfare, and high payoff target strikes with the advantage of underwater covertness. A submarine should be able to withstand the hydrostatic pressure of the deep sea. In this respect, the submarine pressure hull, as the main structural system to resist the external pressure corresponding to the submerged depth, should ensure the survivability from hazards and threats such as leakage, fires, shock, explosion, etc. To do this, the initial scantling of the submarine pressure hull must be calculated appropriately in the concept design phase. The shape of the aft transition ring varies according to its connection with the submarine aft end conical structure, pressure hull cylindrical part, and non-pressure hull of the submarine; the design of the aft transition ring should not only take into account stress flow and connectivity but also the cost increase due to the increased man-hours of its complex geometry. Therefore, trade-off studies based on the four different shapes of the aft transition ring are carried out considering both the review of the structural strength through nonlinear finite element analysis (FEA) and economic feasibility by reviewing the estimations of the manufacturing working days and material costs. Finally, the most rational structural aft transition ring shape for a submarine amongst four reviewed types was proposed.

• Strategy21
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• s.44
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• pp.352-376
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• 2018

Through this research, the current state of naval coordination and guidance of shipping is reviewed whereupon which a suggestion is made for a novel role which satisfies the needs of the people and the country asked of the Navy. Taking into consideration the dynamic security environment, the developing relationship between the two nations on the Korean peninsula, and the influence that the Republic of Korea has on maritime security, it is made more urgent that the Navy takes a proactive course of action in terms of naval coordination and guidance of shipping. The current form of Korean naval coordination and guidance of shipping is adapted from the logical and flexible concepts of NCAPS and NCAGS and is one of many tasks that the Republic of Korea Navy must perform. However, when the Republic of Korea Navy develops blue-water capabilities with the ambitions of protecting its people and their way of life, naval coordination and guidance of shipping could potentially become one of the primary functions of the Republic of Korea Navy that the it must champion. Already, there are indications that foreign navies are, through many developments and commitment towards naval coordination and guidance of shipping, protecting its people and states' interests wherever is necessary. In the case of Chile, its Navy has taken the helm of naval coordination and guidance of shipping and has integrated various maritime organizations including the coast guard and the National Customs Service for the sake of maintaining regional maritime security, showing immediate force if necessary. Presently, as the Republic of Korea Navy looks to be a global naval power, it is important that a reprioritization of the Navy's mission is undertaken, all the while sustaining military readiness posture on the Northern Limit Line. It cannot be any more emphasized how crucial thorough military readiness posture is as a natural stance against the enemy. That being said, contributing towards international maritime security is consistent with the nation's standing. It is a fact that maritime security has been conceptualized and developed merely as a study within the Ministry of Maritime Affairs and Fisheries, the Republic of Korea Navy, and other governmental organizations, forces, and academia. Naval cooperation and guidance of shipping suggested by this research as a practical operational field is a concrete solution to what once was an abstract concept. To stand firm on its status as a maritime nation, the Republic of Korea must establish a Maritime Security Organization within its Navy and develop the appropriate doctrines. Attaining experts, developing doctrines, and cultivating the capability to deploy maritime forces will allow for the Republic of Korea to execute a primary role in keeping international maritime security and naval coordination and guidance of shipping. To fully achieve its latent potential necessitates the Republic of Korea Navy to expedite the introduction of naval coordination and guidance of shipping concepts and to establish the appropriate doctrines, operation plans, and organizations.

• Journal of Korea Technology Innovation Society
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• v.11 no.2
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• pp.264-286
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• 2008

In 2006, the share of energy in Korea amounted to 28% from the total import, 97% from overseas dependency, and 83% for the national Greenhouse Gas (GHG) emission in 2004. Thus, from the aspects of economical and environmental policies, an energy analysis is very important, for the industry to cope with the imminent pressure for climate change. However, the estimation of GHG gas emissions due to an energy use is still done in a primitive way, whereby each industry's usage is multiplied by coefficients recommended from international organizations in Korea. At this level, it is impossible to formulate the prevailing logic and policies in face of a new paradigm that seeks to force participation of developing countries through so called post-Kyoto Protocol. In this study, a hybrid energy input-output (E-IO) analysis is conducted on the basis of the input-output(IO) table of 2000 issued by the Bank of Korea in 2003. Furthermore, according to economic sectors, emission of the GHG relative to an energy use is characterized. The analysis is accomplished from four points of view as follows: 1) estimating the GHG emission intensity by 96 sectors, 2) measuring the contribution ratio to GHG emissions by 14 energy sources, 3) calculating the emission factor of 3 GHG compounds, and 4) estimating the total amount of national GHG emission. The total amount estimated in this study is compared with a national official statistical number. The approach could be an appropriate model for the recently spreading concept of a Life Cycle Analysis as it analyzes not only a direct GHG emission from a direct energy use but also an associated emission from an indirect use. We expect this model can provide a form for the basis of a future GHG reduction policy making.

• Journal of KIISE:Information Networking
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• v.30 no.4
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• pp.474-483
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• 2003

The secret sharing is the basic concept of the threshold cryptosystem and has an important position in the modern cryptography. At 1995, Jarecki proposed the proactive secret sharing to be a solution of existing the mobile adversary and also proposed the share renewal scheme for (k, n) threshold scheme. For n participants in the protocol, his method needs O($n^2$) modular exponentiation per one participant. It is very high computational cost and is not fit for the scalable cryptosystem. In this paper, we propose the efficient share renewal scheme that need only O(n) modular exponentiation per participant. And we prove our scheme is secure if less that ${\frac}\frac{1}{2}n-1$ adversaries exist and they static adversary.

• Journal of Korean Medical Ki-Gong Academy
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• v.19 no.1
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• pp.1-24
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• 2019

Objective : The purpose of this study is to understand a medical Gigong's view of the human body through the analysis of medical Gigong techniques, and to understand the concept and treatment principle of Whidam's Su-Gi therapy as the Angyo(按蹻) Method of Doin Angyo(導引 按蹻) Methods : Among Medical Gigong, Sojucheon practice, Moosim-Gigong Riding stance, Moosim-Gigong Doinbeop, Hwalinsimbang Doinbeop and Donguibogam Jang-Bu Doinbeop were selected to analyze the practice method. The medical Gigong's views of the human body are organized into overviews and pathological perspective. The main concepts and clinical techniques of Whidam's Su-Gi therapy were summarized. Discussion : Understanding the principles of medical Gigong is necessary in order to understand the Angyo method of Doin Angyo. The principle of medical Gigong is to circulate around Three-Danjeon(丹田) on the human belly and Three-Gwan(關) on the human back by practicing medical Gigong, and to strengthen the life force by activating the viscera function by communicating between the limbs and the body. If there are Jeokchwi(積聚) and deviation, Whidam's Su-Gi therapy eliminates the Jeokchwi and adjusts the deviation. Conclusions : 1. The Angyo method of Doin Angyo originates from the practice of training to establish Danjeon for the right body and the right flow of air. 2. The principles of medical Gigong obtained through the analysis of Sojucheon(小周天) practice, Moosim-Gigong Riding stance, Moosim-Gigong Doinbeop, Hwalinsimbang Doinbeop and Donguibogam Jang-Bu Doinbeop are the medical Gigong's view of the human body and pathological perspective. 3. Whidam's Su-Gi therapy, which focuses on the elimination of Jeokchwi and the adjustment of deviation based on the medical Gigong's view of the human body, is a manual therapy that inherits the principle of the Angyo Method of Doin Angyo.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.8
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• pp.359-368
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• 2017

What is the term "intelligence information society", which is a term that has been continuously discussed recently? This means that the automation beyond the limits of human ability in the whole societies based on intelligent information technology is a universalized social future. In particular, it is a concept that minimizes human intervention and continuously pursues evolution to data (or big data) -based automation. For example, autonomous automation is constantly aiming at unmanned vehicles with artificial intelligence as a key element. However, until now, intelligent information research has focused on the intelligence itself and has made an effort to improve intelligence logic and replace human brain and intelligence. On the other hand, in order to replace the human labor force, we have continued to make efforts to replace workers with robots by analyzing the working principles of workers and developing optimized simple logic. This study proposes important strategies and directions to implement intelligent information education policy and intelligent information technology research strategy by suggesting access strategy, education method and detailed policy road map for intelligent information technology research strategy and educational service. In particular, we propose a phased approach to intelligent information education such as basic intelligence education, intelligent content education, and intelligent application education. In addition, we propose education policy plan for the improvement of intelligent information technology, intelligent education contents, and intelligent education system as an important factor for success and failure of the 4th industrial revolution, which is centered on intelligence and automation.