• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.1
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• pp.94-131
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• 2007

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2004 and 2005 has been done. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, ventilation, sanitation and building environment. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation of facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat, humidity was also interesting for comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing topics. Well developed CFD and flow visualization(PIV, PTV and LDV methods) technologies were widely applied for developing facilities and their systems. (2) The research trends of the previous two yews are surveyed as groups of natural convection, forced convection, electronic cooling, heat transfer enhancement, frosting and defrosting, thermal properties, etc. New research topics introduced include natural convection heat transfer enhancement using nanofluid, supercritical cooling performance or oil miscibility of $CO_2$, enthalpy heat exchanger for heat recovery, heat transfer enhancement in a plate heat exchanger using fluid resonance. (3) The literature for the last two years($2004{\sim}2005$) is reviewed in the areas of heat pump, ice and water storage, cycle analysis and reused energy including geothermal, solar and unused energy). The research on cycle analysis and experiments for $CO_2$ was extensively carried out to replace the Ozone depleting and global warming refrigerants such as HFC and HCFC refrigerants. From the year of 2005, the Gas Engine Heat Pump(GHP) has been paid attention from the viewpoint of the gas cooling application. The heat pipe was focused on the performance improvement by the parametric analysis and the heat recovery applications. The storage systems were studied on the performance enhancement of the storage tank and cost analysis for heating and cooling applications. In the area of unused energy, the hybrid systems were extensively introduced and the life cycle cost analysis(LCCA) for the unused energy systems was also intensively carried out. (4) Recent studies of various refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and of alternative refrigerants including carbon dioxide. Efficiency of various compressors and expansion devices are also dealt with for better modeling and, in particular, performance improvement. Thermoelectric module and cooling systems are analyzed theoretically and experimentally. (5) According to the review of recent studies on ventilation systems, an appropriate ventilation systems including machenical and natural are required to satisfied the level of IAQ. Also, an recent studies on air-conditioning and absorption refrigeration systems, it has mainly focused on distribution and dehumidification of indoor air to improve the performance were carried out. (6) Based on a review of recent studies on indoor environment and building service systems, it is noticed that research issues have mainly focused on optimal thermal comfort, improvement of indoor air Quality and many innovative systems such as air-barrier type perimeter-less system with UFAC, radiant floor heating and cooling system and etc. New approaches are highlighted for improving indoor environmental condition as well as minimizing energy consumption, various activities of building control and operation strategy and energy performance analysis for economic evaluation.

• Journal of Korea Water Resources Association
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• v.56 no.11
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• pp.737-749
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• 2023

In this study, we analyzed the hydrological impacts of future climate change on Jeju Island using SSP-based climate change scenarios from 18 climate models and watershed modeling (SWAT-K). Despite discrepancies among climate models, we generally observed an increase in evapotranspiration due to rising future temperatures. Furthermore, a significant increase in runoff and recharge was noted due to increased precipitation. These increasing trends were particularly pronounced in the SSP5-8.5 scenario, and differences among GCM models became more significant in the late 21 century. When compared to the historical period (1981-2010), the projected changes for the far-future period (2071-2100) in the SSP5-8.5 scenario showed a 21.4% increase in precipitation, a 19.2% increase in evapotranspiration, a 40.9% increase in runoff, and a 16.6% increase in recharge on an annual average basis. On a monthly basis in the SSP5-8.5 scenario, precipitation was expected to increase by 24.5% in September, evapotranspiration by 34.1% in April, runoff by 58.1% in October, and recharge by 33.8% in September. To further assess projections based on extreme climate scenarios, we selected two models, CanESM5 and ACCESS-ESM1-5, which represented the maximum and minimum future precipitation forecasts, and compared the hydrological changes in the future scenarios. The results indicated that runoff and recharge rates were relatively higher in the CanESM5 model with the highest precipitation forecast, while evapotranspiration rates were higher in the ACCESS-ESM1-5 model with the lowest precipitation forecast. Based on the climate change scenarios used in this study, the overall available water resources on Jeju Island are more likely to increase. However, since results vary by season and region depending on the climate model and scenario, it is considered necessary to conduct a comprehensive analysis and develop response measures using various scenarios.

• Journal of KIBIM
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• v.2 no.1
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• pp.27-39
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• 2012

Public construction projects need complex and multi-functional management skill, since the most of public construction projects are comprised of multi-project and mega-projects. In order to effectively manage construction projects, PMIS is widely used. However the majority of the current PMIS have been developed as a single project-oriented business management system. Thus compatibility problems are encountered during the process of integrating the entire systems to manage the multi-complex projects. In addition, the form of orders applying BIM are increased recently, but the research and development of BIM based PMIS are still lacking. In this study, therefore, the functions of PMIS main objectives based on the analysis of PMIS As-Is and To-Be of PMIS, the dual management system utilizing Internet and Intranet will be proposed to integrate the individual PMIS with Integrated Program Management System. Rather than combining commercial BIM tool and PMIS directly, which is the common method of failure, the sequential process model to adopt BIM based PMIS is also explained. Step-by-step development method of BIM based PMIS is suggested to prepare for the activation of BIM technology in the nearest future.

• Korean Journal of Construction Engineering and Management
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• v.13 no.6
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• pp.143-152
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• 2012

As the Public Procurement Service announced the compulsory of BIM adaption in every public construction from 2016, the importance of BIM is increasing. Besides, automatic code checking takes significance in terms of the quality control for BIM based design. In this study, rule-sets were defined for Act on the Promotion and Guarantee of Access for the Disabled, the Aged, and Pregnant Women to Facilities and Information. Three analytic steps were suggested to shortlist the objective clauses from the entire code; the frequency analysis using project reviews for architectural code compliance, the clause analysis on quantifiability, and the analysis for model checking possibilities. The shortlisted clauses were transformed into the machine readable rule-set definition. A case study was conducted to verify the adaptiveness and consistency of rule-set definitions. In future study, it is required the methodologies of selecting objective clauses to be specified and its indicators to be quantified. Also case studies should be performed to determine the pre-conditions in modeling and to check interoperability issues and other possible errors in models.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.4
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• pp.375-382
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• 2011

There is no system to obtain the basic data and proceed data and user input interface is complex, thus there are some limitation to utilize the oil spill prediction model. It is difficult to build the scientific response strategy in order to respond oil spill accident rapidly because it is impossible to operate the oil spill prediction model any time. In this study, the optimum operational system for oil spil prediction model has been developed considering the present system. External real time data has been linked because of impossibility of building all basic data and minimum database has been build in this study. Through this data system, real time oil spill prediction model can be utilized. And the user interface has been designed to reduce the error of the interface between user and model and the output interface has been proposed to analyze the result of modeling at multidimensional aspect. While the system for oil spill prediction model as the result of this study has some uncertainties because of depending on external data, the thing that we can predict oil spill using operate the model rapidly as soon as the accident occurred can be meaning in the response field.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.4
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• pp.157-169
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• 2010

In this study, the applicability of SRTM(The Shuttle Radar Topography Mission) DEM(Digital Elevation Model) which is one of the remotely sensed shuttle's radar digital elevation was tested for use as the input data in a grid-based rainfall-runoff model. The SRTM DEM and digital topographic map derived DEM(TOPO DEM) were building with 500m spatial resolution for the Chungju-Dam watershed which located in the middle east of South Korea, and stream-burning method was applied to delineate the proper flow direction for model application. Similar topographical characteristics were shown as a result of comparing elevation, flow-direction, hydrological slope, number of watershed cell, and profile between SRTM DEM and TOPO DEM. Two DEMs were tested by using a grid-based rainfall-runoff model named KIMSTORM with 6 storm events. The results also showed no significant differences in average values of relative error for both peak runoff(0.91 %) and total runoff volume(0.29 %). The results showed that the SRTM DEM has applicability like TOPO DEM for use in a grid-based rainfall-runoff modeling.

• The Journal of the Acoustical Society of Korea
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• v.34 no.5
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• pp.385-393
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• 2015

The speed of train has rapidly been increased in accordance with the developed railway technology. Nowadays, high-speed trains were introduced which has the speed faster than 400 km/h. In Korea, a lots of efforts were undertaken to increase the speed of train faster than 350 km/h, however noise and vibration are still the main problems to solve for realization of the high-speed train. In the case of operation speed faster than 350 km/h, it can be easily presumed that the noise and vibration damages could be increased in the train stations which are close to the passing railway tracks. Thus, the noise in the five different types of high-speed train stations were analyzed including stations built on the ground, underground, under rail, and two types on rail. The present paper predicts noises inside the stations depending on the speed of the passing trains and analyze the noise comparing with noise criteria (NC). Sound insulation performance of each part of buildings was calculated using the transmission noise formula and computer modeling, Finally, a series of processes were introduced to satisfy the aural environment with the optimum interior noise criteria by changing interior finishing materials.

• The Journal of the Korea Contents Association
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• v.20 no.6
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• pp.653-667
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• 2020

The Purpose of this study is to propose an effective service delivery system for children and youth considering service users and developmental stage. To accomplish this purpose, this study examined public service utilization for children and youth focusing on age difference, using statistical method and network analysis. The key results were as follows. The significant difference of service utilization among different age groups appeared in community center, youth training center, healthy family support center, public health center, public office and office of education. In terms of service utilization for special needs, the differences in Wee Center, Wee School and community child center were significant. Top value of degree centrality in network analysis showed on public heath center for elementary school, youth training center for middle school, and community center for high school. Finally, modeling results by Concor presented several distinctive relationship patterns in public service utilization for children and youth according to different age groups. On the base of these results, building a gateway applying age difference and developing a individualized service utilization database were suggested to improve the quality of service delivery system for children and youth.

• Korean Journal of Cognitive Science
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• v.28 no.2
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• pp.111-131
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• 2017

The connectionist model is one approach to studying language processing from a computational perspective. And building a representation in the connectionist model study is just as important as making the structure of the model in that it determines the level of learning and performance of the model. The connectionist model has been constructed in two different ways: localist representation and distributed representation. However, the localist representation used in the previous studies had limitations in that the unit of the output layer having a rare target activation value is inactivated, and the past distributed representation has the limitation of difficulty in confirming the result by the opacity of the displayed information. This has been a limitation of the overall connection model study. In this paper, we present a new method to induce distributed representation with local representation using abstraction of information, which is a feature of restricted Boltzmann machine, with respect to the limitation of such representation of the past. As a result, our proposed method effectively solves the problem of conventional representation by using the method of information compression and inverse transformation of distributed representation into local representation.

• Journal of Korea Spatial Information System Society
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• v.1 no.2 s.2
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• pp.99-113
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• 1999

The role of a GIS as a tool for a national information infrastructure can best be fulfilled once GIS standards are implemented. In this paper, we have identified what the contents of GIS standards in other countries are, and what should be the future direction for implementing a nation's GIS standards. Based on a detailed review on GIS standards in the USA, Australia, Japan and the United Kingdom, we derived the following: (1) A nations's GIS standards should include both geographic information content standards and geographic information service standards: (2) A nation's GIS standards should be a profile of ISO GIS standards: (3) Each GIS standards should be developed on the bassis of the Entity-Relationship Model using Unified Modeling Language: and (4) Experts in GIS should pay much more attention on studies on GIS service standardization. As for building the national GIS Standards for Korea, we recommend both GIS Content Standards and GIS Service Standards be simultaneously developed. GIS Content Standards include geographic feature content standard, feature classification standard, portrayal standard, rules for application standards, spatial reference model and terminology. GIS Service Standards include standards for data sharing such as metadata standard and transfer standard, quality standard, quality principle and portrayal standards.