• Journal of the Korea Safety Management & Science
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• v.15 no.4
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• pp.407-416
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• 2013

This paper proposes an approach to analyzing the relationship between technology and services, and to identifying promising service areas for technology-based firms with the analysis of business model (BM) patents. First, BM patents and technology patents are collected and classified into their relevant categories, respectively. Second, patent citation analysis is conducted to analyze the linkage and impacts between each technology and service field at macro level. Third, as a micro level analysis, patent co-classification analysis is employed to identify the interrelationships among specific technology and service areas. Finally, the promising service areas for technology-based firms seeking service areas for diversification is investigated with portfolio analysis. The working of the proposed approach is provided with the help of a case study of IT and mobile services. The proposed approach could guide and help managers of technology-based firms to discover the opportunity of the diversification to new areas in emerging service fields.

• Structural Engineering and Mechanics
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• v.4 no.3
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• pp.313-329
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• 1996

A mathematical model of a cable as a system of interacting wires with interwire friction taken into account is presented in this paper. The effect of friction forces and the interwire slip on the mechanical properties of tension cables is investigated. It is shown that the slip occurs due to the twisting and bending deformations of wires, and it occurs in the form of micro-slips at the contact patches and macro-slips along the cable. The latter slipping starts near the terminals and propagates towards the middle of the cable with the increase of tension, and its propagation is proportional to the load. As the result of dry friction, the load-elongation characteristics of the cable become quadratic. The energy losses during the extension are shown to be proportional to the cube of the load and in inverse proportion to the friction force, a result qualitatively similar to that for lap joints. Presented examples show that the model is in qualitative agreement with the known experimental data.

• Composites Research
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• v.18 no.4
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• pp.44-51
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• 2005

In this paper, we developed the direct numerical simulation(DNS) model considering the geometry of yams which consist of 3D orthogonal woven composite materials, and using this model, the dynamic behavior of under transverse low-velocity impact has been studied. To build up the micromechanical model considering tow spacing and waviness, an accurate unit structure is presented and used in building structural plate model based on DNS. For comparison, DNS results are compared with those of the micromechanical approach which is based on the global equivalent material properties obtained by DNS static numerical tests. The effects with yarn geometrical irregularities which are difficult to consider in a macroscopic approach are also investigated by the DNS model. Finally, the multiscale model based on the DNS concepts is developed to enhance efficiency of analysis with real sized numerical specimen and macro/micro characteristics are presented.

• Korean Journal of Remote Sensing
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• v.35 no.1
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• pp.137-149
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• 2019

Traffic emissions are the main cause of environmental pollution in cities and respiratory problems amongst people. This study developed a model based on an integration of support vector regression (SVR) algorithm and geographic information system (GIS) to map traffic carbon monoxide (CO) concentrations and produce prediction maps from micro level to macro level at a particular time gap in a day in a very densely populated area (Utara-Selatan Expressway-NKVE, Kuala Lumpur, Malaysia). The proposed model comprised two models: the first model was implemented to estimate traffic CO concentrations using the SVR model, and the second model was applied to create prediction maps at different times a day using the GIS approach. The parameters for analysis were collected from field survey and remote sensing data sources such as very-high-resolution aerial photos and light detection and ranging point clouds. The correlation coefficient was 0.97, the mean absolute error was 1.401 ppm and the root mean square error was 2.45 ppm. The proposed models can be effectively implemented as decision-making tools to find a suitable solution for mitigating traffic jams near tollgates, highways and road networks.

• Journal of Families and Better Life
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• v.26 no.1
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• pp.51-67
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• 2008

The study analyzes divorce rates in Korea and makes suggestions for the future research of divorce rates. Based on the data from Korea Statistical Information System (KOSIS) of the National Statistics Organization, trends for divorce rates change and the relations between divorce rates and macro environmental factors are analyzed. Macro environmental factors include socioeconomic factors such as, Korean War, Vietnam War, oil shock, IMP economic crisis and gross national income (GNI), whereas demographical factors include population structure, rates of female labor participation, and geographical location. The principle characteristics of divorce rates are as follows: 1) the Crude divorce rates (CDR) and the number of divorced had been increased from 1970 to 2004, then the trend changed to a decrease; 2) the slope of the change were the highest during 1998 to 2004 after the IMP economic crisis. The relations between socioeconomic factors are as follows: 1) during the war there was a small increase of CDR for a short period of time; 2) the economic crisis of the nation tend to increase the CDR, while the IMP economic crisis had a strong impact on an increase of CDR because of the interaction effect among the population structure, women's sex role changes as well as the level of standard of living. The increase in CDR from 1990 to 2000 can be explained partly by the population of baby Boomers passing through their marriage and divorce process. The number of population residing in the rural area and the middle class households, and the mobility of population also had an impact on the divorce rates changes. The recommendations for the future research were as follows: 1) the need to develop new divorce statistics that are based on a marriage cohort or a birth cohort because family behavior is a mixture of personal, social and political responses, and because CDR is not an accurate measure of divorce rate since it was influenced by population structure; 2) the need to include micro personal factors as well as macro social factors in a model to find an interaction effect between those variables.

• Journal of the Korean Society of Costume
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• v.22
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• pp.23-44
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• 1994

The purpose of this study was to clarify the cultural characteristic of dress and adornments by examining articles on dress adornments and related items in Korean newspaper over periods historically and objectively by means of content analysis. This study attempted to at-tain a macro-cultural view by analysing to at-tain a macro-cultural view by analysing closely the cultural characteristics of dress and adornments as a micro-cultural system through culturally based model suggested by hamilton. The two-hundreds and eighty articles on dress and adornments were selected from newspapers(most by form Chosun Ilbo and partly from Maeil Shinbo) pulished between 1920 and 1990. The results were as follows: 1. The culture of dress and adornment received much attention during the 1930's and 1960's and little during 1950's. 2. Various cultural characteristics of dress and adornments appeared on and after 1960's: reporting more foreign news items showing foreign-oriented and future-oriented features showing cultural relativism. In the 1920's and 1970's the contents of news items on dress and adornments show the most common- mass- oriented character. Foreign-oriented cultural tendencies in cloth-ing were increasing during from 1960's to 1970's but the tendencies were turned to rather tradition-oriented features on and after 1980's compare with 1960's-1970's. Advisory critical articles on dress and adornments were small in number and insignificant but compare with other periods these received much atten-tion during the 1920's and 1980's. 3. Ideological components received much at-tention on and after 1920's to 1990. Techo-nological components received much attention during 1920's and little during 1960's. The social structural components received a little attention on and after 1920's-1940's and 1990. 4. News items on women's dress and adornments received much attention from the 1920's to 1960's and news items on both men's and women's dress and adorments were in-creasing and received much attention on and after the 1970's. 5. The pragmatic cultures were mostly re-lated to techonological components and evaluative-normative culture were mostly re-lated to ideological and social structural components. In the light of these results dress and adorments as a cultural sub-system comprise a dynamic inteacting system that articulated directly with the macro-cultural system.

• Health Policy and Management
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• v.19 no.4
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• pp.33-52
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• 2009

Health promotion policies have needed to assess in detailed and evidence-based work to set a policy goal and clear future directions of health promotion in Korea. To identify the major factors related with health promotion, we assessed the associations between public health outcome (potential years of life loss, PYLL) and national health determinants. For this purpose, we used a pooled cross sectional time-series regression analysis with corrected fixed effect models involving sixteen member countries of the Organisation for Economic Cooperation and Development during the period 1970 to 2001. The PYLL was positively associated with tobacco and alcohol consumption (model 1 and 2) and calories intake (model 2 and 3) while the PYLL was negatively associated with GDP, fruit and vegetable intake (model 2), number of doctors (model 3), coverage rates of health care security, and elderly population rates (model 4). In conclusion, health behaviors related with tobacco, alcohol, and nutrition were significant health determinants for health outcome. Overall analysis results of this study will provide a guidance toward improved macro- and micro-policy development for future health promotion policy in Korea.

• Structural Engineering and Mechanics
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• v.80 no.5
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• pp.523-538
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• 2021

The mechanical behaviour and stability of coal mining engineering underground is significantly affected by ground water. In this study, nuclear magnetic resonance imaging (NMRI) technique was employed to determine the water distribution characteristics in coal specimens during saturation process, based on which the functional rule for water distribution was proposed. Then, using discrete element method (DEM), an innovative numerical modelling method was developed to simulate water-weakening effect on coal behaviour considering moisture content and water distribution. Three water distribution numerical models, namely surface-wetting model, core-wetting model and uniform-wetting model, were established to explore the water distribution influences. The feasibility and validity of the surface-wetting model were further demonstrated by comparing the simulation results with laboratory results. The investigation reveals that coal mechanical properties are affected by both water saturation coefficient and water distribution condition. For all water distribution models, micro-cracks always initiate and nucleate in the water-rich area and thus lead to distinct macro fracture characteristics. With the increase of water saturation coefficient, the failure of coal tends to be less violent with less cracks and ejected fragments. In addition, the core-wetting specimen is more sensitive to water than specimens with other water distribution models.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4975-4983
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• 2010

In this paper, the ordinariest and strongest simulator that many used to power electronics circuits and many different control technology can apply to more easily understand modeling the element, PSPICE and MATLAB are adapted a micro IGBT, a macro IGBT, PWM generator and to library moeling of validity of the Induction motor is interpreted. Micro IGBT model of demagnetization quality proved for modeling accuracy to through experiment, macromodel IGBT were simulated which the applied to voltage type PWM inverter to the cyclo-converter and induction motor of demagnetization.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.67-70
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• 2004

An investigation was performed to study the impact damage of the laminated composite plates caused by a low- velocity foreign object with multi-scale modeling based on the concepts of Direct Numerical Simulation (DNS)[4]. In the micro-scale part, we discretize the composite plates through separate modeling of fiber and matrix for the local microscopic analysis. A micro-scalemodel was developed for predicting the initiation of the damage and the extent of the final damage as a function of material properties, laminate configuration and the impactor's mass, etc. Anda macro-scale model was developed for description of global dynamic behavior. The connection betweenmicroscopic and macroscopic is implemented by the tied interface constraints of LS-DYNA contact card. A transient dynamic finite element analysis was adopted for calculating the contact force history and the stresses and strains inside the composites during impact resulting from a point-nose impactor. The low-velocity impact events such as contact force, deformation, etc. are simulated in the macroscopic sense and the impact damages, fiber-breakage, matrix cracking and delamination etc. are examined in the microscopic sense.