• Journal of the Korea Society of Computer and Information
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• v.11 no.4 s.42
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• pp.221-230
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• 2006

Changing drastically, the life in a modern city has forced citizens to gradually shorten their average period of settlement, which has weakened the identity of city habitation, thus causing serious crimes and damaging the security of city greatly. Haying a highly composite structure with not only macro, but micro characteristics, city is grasped as a very composite phenomenon shown in the social, economic and spatial constitution relationships, including the personal motives of criminals. Accordingly, this study puts stress on the necessity of any crime prediction program to predict the occurrence of crimes by analyzing the occurrence patterns of sharply increasing intra-city crimes of violence on a typical, time and spatial basis and clarifying their structural dynamic relationships in a both macro and micro manner. Moreover, the deduction of various factors closely related to crime occurrence will contribute to elucidating the occurrence structure of city crimes.

• Korean Journal of Materials Research
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• v.31 no.3
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• pp.115-121
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• 2021

MnO2 can be potentially utilized as an electrode material for redox capacitors. The deposition of MnO2 with poor electrical conductivity onto porous carbons supplies them with additional conductive paths; as a result, the capacitance of the electrical double layer formed on the porous carbon surface can be utilized together with the redox capacitance of MnO2. However, the obtained composites are not generally suitable for industrial production because they require the use of expensive porous carbons and/or inefficient fabrication methods. Thus, to develop an effective preparation procedure of the composite, a suitable structure of porous carbons must be determined. In this study, MnO2/C composites have been prepared from activated carbon gels with various pore sizes, and their electrical properties are investigated via cyclic voltammetry. In particular, mesoporous carbons with a pore size of around 20 nm form a composite with a relatively low capacitance (98 F/g-composite) and poor rate performance despite the moderate redox capacitance obtained for MnO2 (313 F/g-MnO2). On the other hand, using macro-porous carbons with a pore size of around 60 nm increases the MnO2 redox capacitance (399 F/g-MnO2) as well as the capacitance and rate performance of the entire material (203 F/g-composite). The obtained results can be used in the industrial manufacturing of MnO2/C composites for supercapacitor electrodes from the commercially available porous carbons.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.11a
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• pp.7.2-7.2
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• 2009

Nanoporous bioactive glass(NBG) ceramic with well interconnected pore structures were fabricated bytriblock copolymer templating and sol-gel techniques. Hierarchically porous BGbeads were also successfully synthesized by controlling the condition of solvent.The beads have hierarchically nano- and macro-pore structure with a sizesbetween several tens nanometers and several hundred micrometers. Both NBG andBG beads show superior bone-forming bioactivity and good in vitrobiodegradability. Biocompatibility both in vitro and in vivo were examed andwas revealed that it largely relies on the pore morphology as well ascomposition. Our synthetic process can be adapted for the purpose of preparingvarious bioceramics, which have excellent potential applications in the fieldof biomaterials such as tissue engineering and drug storage.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.118-130
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• 1995

Fuel spray in a gasoline engine is a significant factor for the decision of engine power, pollutant emission and the design of intake manifold system. Three kinds of fuel which has other physical properties are chosen in this study, and it is observed using an image processing method that the mechanism and structure of free fuel spray with a throttle type gasoline injector, and the detailed characteristics of droplet size and velocity distributions are obtained by macro and micro-scopic measuring method respectively. It is verified that the initial breakup behaviors are depended on We like the result of Reitz's study, and also observed that the spray of octane and solvent with Re of 210~330 and 270~330 respectively are better than ethanol which has relatively high density and viscosity.

• Structural Monitoring and Maintenance
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• v.3 no.1
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• pp.71-90
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• 2016

The paper reports a wide overview of the scientific activities on Structural Health Monitoring (SHM) in Italy. They are classified on three different conceptual scales: national territory (macro); regional area (medium); single structure (small). In the latter case differences have been pointed out between permanent installation and short-term experimental campaigns. A particular focus has been dedicated to applications devoted to cultural heritage which have an important historic, strategic and economic value for Italy. Two specific cases, the first related to the permanent monitoring of an historical Basilica and the second regarding the dynamic testing of a modern structure, have been presented as a basis for a general discussion.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.579-581
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• 1988

This paper proposes the logic simulation for hierarchical logic network with function descriptor base data structure and algorithm on which a macro cell is considered as a logic elements. Function descriptor base data structure is useful when many logic elements of which type is same exist in a network, for it lessens the computer memory size used during the simulation. And the proposed simulation algorithm may improve the simulation speed.

• Journal of Korea Port Economic Association
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• v.19 no.1
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• pp.139-159
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• 2003

This study deals sith some problems of foreign direct investment and seeks for the ways of activating foreign direct investment (hereafter F.D.I.) by analyzing the Korean economic structure that is faced with the neo-protectivism and nationalism of the advanced or foreign countries currently. During a transformational process in the transitional period of world trade environment, it is necessary for Korea not only to learn the higher technology for advanced countries, but also to apply techonology to their economic structure in order to enter into competition with the advanced countries. Based on the experiences and accomplishments from their investments, Korean enterprises should turn their business into F.D.I. and act appropriately in order to keep the balance between indoor and outdoor investment. Looking through the ways to activate F.D.I., we may make conclusions as follows: 1. Government policy transparency 2. Prudential Macro Economic policy 3. International policy coorperation system 4. Solidification of Foreign Commercial intercourse to Developing countries 5. Globalixation base of domestic coorperation 6. High efficiency- low cost of business coorperation enterprise 7. Attacktive investiestment strategies on conclusive competive advantage 8. Multilateral investment Area 9. New recognixation on marketing investment etc. F.D.I. strategies

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.7
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• pp.2326-2336
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• 1996

So most practical combustor is considered to the swirl flame, it is very important to examinate swirl flame structure and combustion characteristics. Recently, attention has been paid to the flame diagnostic by radical luminous intensity. For swirl flame structure and combustion characteristic, reverse flow boundary, temperature, ion current and radical luminous intensity were measured in the double-coaxial swirl combustor which was used principle of multi-annular combustor. This study had three experimental condition, S-type, C-type, SC-type. S-type and C-type flames were formed recirculation zone, but SC-type flame wasn't formed. C-type flame had two recirculation zone. The position with maximum value of ion current and CH-radical, temperature and OH-radical had similarity distribution almost. Therefore, it is possible that the macro structure of flame was measured by radical luminous intensity in the high intensity of turbulent combustion field which was formed by swirl.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.02a
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• pp.266-273
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• 2002

Milli-structure components are classified as a component group whose size is between macro and micro scales, that is, about less than 20mm and larger than 1mm. The bending of these components of thin sheets has a typical phenomenon of bulk deformation because of the forming size. The recent trend towards miniaturization causes an increased demand for parts with very small dimensions. The conceptual miniature bending process enables the production of such parts with high productivity and accuracy. The stress values of the flow curve decrease with miniaturization, which means that coarse grained materials show a higher resistance against deformation, when the grain size is in the range of the sheet thickness. In this paper, a new numerical approach is proposed to simulate intergranular milli-structure in forming by the finite element method. The grain element and grain boundary element are introduced to simulate the milli-structure of strip in the bending. The grain element is used to analyze the deformation of individual grain while the grain boundary element is for the investigation on the movement of the grain boundary. Also, the result of the finite element analysis is confirmed by a series of milli-sized forming experiments.

• Journal of the Korea institute for structural maintenance and inspection
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• v.7 no.1
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• pp.279-288
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• 2003

This study is the development of method on repairing concrete structure for progressing the durability of reinforced concrete. This method is wet spray method which compress and conduct mortar pre-mixed with polymer powder to hose by high pressure pump and spray it on the section of concrete structure through nozzle made specially. Characters of this method are that materials are selected with the sort of structure and the cause of deterioration and macro pores are removed in repaired section by conducting with high pressure and spraying with high velocity for progressing the durability of concrete structure. This study has carried out that the minimum capacity of rebound was measured with various condition and physical properties of sample made by spray method were estimated in comparing with sample made by previous hand method. Also, properties of long-term have carried out after this method was applied on site. According to experimental study, the capacity of rebound showed below 5% and physical properties of sample made by spray method were superior to that of sample made by hand method and physical and durable properties of long-term showed excellence.