• Korean Journal of Construction Engineering and Management
• /
• v.12 no.3
• /
• pp.73-82
• /
• 2011

The term 'green' has become an important way of survival for the construction industry in 21th century in accordance with the emergence of the environmental crisis due to the climatic change. Especially the policy of carbon taxation, planed to be introduced from 2012, is expected to be a considerable burden to the construction industry which has abundant carbon emission during the resource transportation due to the complexity of resources and local distribution of the construction sites. In this regard, this study shows an optimizing strategy for delivery frequency, which downsizes the net distribution costs based on the assumption that, despite of its other advantagements, the frequent small lot mode of JIT delivery would take negative effects due to the increase of costs of transportation and carbon emission once the carbon taxation policy carried out. To simulate the efficiency of the management strategies, the System Dynamics modeling has been used. The results show that the frequent small lot transportation strategy is now always efficient method to these changes, and that the frequency of transportation should be re-determinated according to the extent of the imposition of carbon tax. This study provides the conceptual frame for an efficient management of transportation system of the construction industry, showing necessity of change of the resource transportation systems through analysing JIT deliver system in accordance with the global changes in environmental economy.

• Journal of KIISE:Databases
• /
• v.27 no.1
• /
• pp.53-63
• /
• 2000

The mobile computing service market is increasing rapidly due to the development of low-cost wireless network technology and the high-performance mobile computing devices. In recent years, several methods have been proposed to effectively deal with restrictions of the mobile computing environment such as limited bandwidth, frequent disconnection and short-lived batteries. Amongst those methods, much study is being done on the caching method - among the data transmitted from a mobile support station, it selects those that are likely to be accessed in the near future and stores them in the local cache of a mobile host. Existing cache replacement methods have some limitations in efficiency because they do not take into consideration the characteristics of user mobility and spatial attributes of geographical data. In this paper, we show that the value and the semantic of the data, which are stored in the cache of a mobile host, changes according to the movement of the mobile host. We argue it is because data that are geographically near are better suited to provide an answer to a users query in the mobile environment. Also, we define spatial location of geographical data has effect on, using the spatial attributes of data. Finally, we propose two new cache replacement methods that efficiently support user mobility and spatial attributes of data. One is based on the location of data and the other on the meaningful region of data. From the comparative analysis of the previous methods and that they improve the cache hit ratio. Also we show that performance varies according to data density using this, we argue different cache replacement methods are required for regions with varying density of data.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37C no.11
• /
• pp.1170-1181
• /
• 2012

Wireless Sensor Networks(WSNs) are used in diverse applications. In general, sensor nodes that are easily deployed on specific areas have many resource constrains such as battery power, memory sizes, MCUs, RFs and so on. Hence, first of all, the efficient energy consumption is strongly required in WSNs. In terms of event states, event-driven deliverly model (i.e. surveillance and reconnaissance applications) has several characteristics. On the basis of such a model, clustering algorithms can be mostly used to manage sensor nodes' energy efficiently owing to the advantages of data aggregations. Since a specific node collects packets from its child nodes in a network topology and aggregates them into one packet to relay them once, amount of transmitted packets to a sink node can be reduced. However, most clustering algorithms have been designed without considering can be reduced. However, most clustering algorithms have been designed without considering characteristics of event-driven deliverly model, which results in some problems. In this paper, we propose enhanced clustering algorithms regarding with both targets' movement and energy efficiency in order for applications of surveillance and reconnaissance. These algorithms form some clusters to contend locally between nodes, which have already detected certain targets, by using a method which called CHEW (Cluster Head Election Window). Therefore, our proposed algorithms enable to reduce not only the cost of cluster maintenance, but also energy consumption. In conclusion, we analyze traces of the clusters' movements according to targets' locations, evaluate the traces' results and we compare our algorithms with others through simulations. Finally, we verify our algorithms use power energy efficiently.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.12
• /
• pp.546-554
• /
• 2019

Typically, closed-circuit television (CCTV) monitoring is mainly used for post-processes (i.e. to provide evidence after an incident has occurred), but by using a streaming video feed, machine-based learning, and advanced image recognition techniques, current technology can be extended to respond to crimes or reports of missing persons in real time. The multi-CCTV cooperation technique developed in this study is a program model that delivers similarity information about a suspect (or moving object) extracted via CCTV at one location and sent to a monitoring agent to track the selected suspect or object when he, she, or it moves out of range to another CCTV camera. To improve the operating efficiency of local government CCTV control centers, we describe here the partial automation of a CCTV control system that currently relies upon monitoring by human agents. We envisage an integrated crime prevention service, which incorporates the cooperative CCTV network suggested in this study and that can easily be experienced by citizens in ways such as determining a precise individual location in real time and providing a crime prevention service linked to smartphones and/or crime prevention/safety information.

• Journal of Korean Society for Geospatial Information Science
• /
• v.17 no.2
• /
• pp.19-26
• /
• 2009

The Ministry of Land, Transport and Maritime Affairs(MLTM) project for the DB construction of national geotechnical information was automatically computerized the geotechnical investigation results on the construction site in 2007. So 'the rule for computerizing of geotechnical investigation results and its application' were promoted the establishment and applicable project. It was promoted in earnest that all organization and affiliation of MLTM, local governments included the project because of stabilization of the law from 2008. We have analyzed a application-ratio of geotechnical information about users of geotechnical information system and distribution data and established a plan of applying enhancement for the DB construction and DB utilization in 2008. In this paper, we propose the result for application-ratio analysis and application plan through the application-case study of national geotechnical information DB. In the application-ratio analysis, the analysis in the field shows the most high as 39% in construction planning and preliminary investigation, the analysis in the effect of capabilities shows the most high as 25% in the increased efficiency of business. Also the analysis in the field of application shows the most high as 95% a application-ratio of geotechnical information in architecture and civil.

• Economic and Environmental Geology
• /
• v.49 no.5
• /
• pp.361-370
• /
• 2016

It is well known that the inflow of rainwater and the infiltration of groundwater to sewerage (I/I) increase the sewage and burden sewage treatment plants and lower their treatment efficiency. Therefore, it is important to estimate the amount of I/I. In this study, well groundwaters, public water supplies (PWSs), and sewage and rainwater channels were investigated to check whether oxygen and deuterium isotopes could be used as a tool for I/I estimation. This study shows that the isotopic composition of PWS in Jeonju area is very consistent over time and distinctly lighter than the circulating local rainwater (CLR) because it is supplied from Yongdam Dam, which is located about 40 km inland to the east in the mountainous area. Considering the fact that sewage mostly originates from the PWS, we could calculate the amounts of CLR in the sewerage from a monitoring station using unaffected rainwater and tap water as mixing end members. The calculation revealed that the CLR fraction ranged from 50% to 90% depending on observation time. This is well supported by the dilute natures of the sewages at the station. The fraction of PWS in investigated well waters were about 46%, indicating that leaking of PWS is very serious and is an important groundwater source in the study area. Since the infiltration of such groundwater may not alter the isotopic composition of sewage significantly, the actual I/I would be much greater than the calculated ones.

• Journal of Environmental Impact Assessment
• /
• v.13 no.3
• /
• pp.125-135
• /
• 2004

Environmental Impact Assessment(EIA) in Korea has been used to improve environmental conservation and decision-making. Since environmental impact statement(EIS) was introduced in 1981 with the promulgation of the Environmental Preservation Act in 1977, which replaced the Pollution Control Act legislated in 1963. With a rapid growth of environmental perception as well as the diversification of development activities, however, it has recently bring about a strong demand for a new assessment process related to the strategic level of policies, plan, programs. Method of this study includes analyses of the situation of local EIA and its problematic issues through survey and analysis of information and data, analysis of the level of environmental awareness of professionals and case studies including analysis of foreign strategic environmental assessment. Accordingly, I have elicited a concept of SEA. In addition, I have studied on costs of environmental assessment, and efficiency of internalization of HIA. The survey was carried between September and November 2003, and 177 professionals were asks to complete a questionnaire. As a result of questionnaire survey of environmental pundits, it revealed that 83.8% of participants were in favor of introduction of strategic assessment. This result demonstrated more or less higher approval rate than those of awareness survey done by the Ministry of Environment, i.e. 86.0% ayes, and 14.0% nays. 22.8% of participants agreed to the opinion; "For introduction of this system, earlier is better," 50% reported having an opinion such as, "Will introduce this system in an earliest possible time after correcting problems," 26.3% reported having an opinion such as, "Let's decide the time for introduction of this system after correcting problems first,' and 0.9% reported having an opinion, "it's too early to introduce this system." Specifically, the ratio of ayes on introduction of the system marked 72.8%, and it revealed that a majority of respondents have an opinion such as, "Will introduce this system in an earliest possible time after correcting problems." As means of solutions for the problem regarding the limits of applications that existed in SEA System, factors, such as collecting a wide variety of opinions, securing experts, and faithful implementation, etc. were reported important, and in addition to these factors, respondents revealed having opinions such as, consistent research and development, reflection of public interest, establishment of professional organization, enforcement of after-management service, expanding investments in large, systemizing reference materials, and encouraging public participation, etc. To improve problems involving with present EIA system, it has been identified through this study that SEA is efficient and useful. In order to have SEA introduced successfully, it has been cleared that internalization of effectiveness of environmental cost together with HIA must be accomplished.

• International Journal of Highway Engineering
• /
• v.8 no.4 s.30
• /
• pp.37-47
• /
• 2006

The road sign is one of street furnitures functioning to guide directions for drivers. The road sign should be employed and designed to help drivers find their destinations easily and accurately. It is obvious that the road sign is one of the main components that enhance efficiency and safety of driving environments. The current way of guiding strategy at road signs in Korea is a system for mainly guiding 'points' although a new system guiding 'road names' and 'street numbers' with the introduction of new address system is now being introduced on urban areas. When the regional territory management offices and local governments try to employ current road sign systems, they are supposed to follow the sign regulations which contains standard project processes, selection methods of guiding points, character size and design, and location selection for each road sign. However, the current road sign regulations are very complex to understand and unclear for a person in charge to do tasks described above. Especially, selection process and criteria of guiding points are cumbersome and controversial. Furthermore, non sufficient ways of selecting guiding points considering road functions and geographic characteristics decrease the connectivity of guiding points. This study develops enhanced ways of increasing connectivity of successive guiding points through three case studies. Developed ways will help highway agencies and officials understand how to improve the connectivity of road signs.

• Journal of Korean Society on Water Environment
• /
• v.28 no.3
• /
• pp.375-383
• /
• 2012

Soil erosion has been emphasized as serious environmental problem affecting water quality in the receiving waterbodies. Recently, Best Management Practices (BMPs) have been applied at a field to reduce soil erosion and its effectiveness in soil erosion reduction has been monitored with various methods. Although monitoring at fields/watershed outlets would be accurate way for these ends, it is not possible at some fields/watersheds due to various limitations in direct monitoring. Thus modeling has been suggested as an alternative way to evaluate effects of the BMPs. Most models, which have been used in evaluating hydrology and water quality at a watershed, could not reflect rainfall intensity in runoff generation and soil erosion processes. In addition, source codes of these models are not always public for modification/enhancement. Thus, runoff-sediment evaluation system using hourly rainfall data and vegetated filter strip (VFS) evaluation module at field level were developed using open source MapWindow GIS component in this study. This evaluation system was applied to Bangdongri, Chuncheonsi to evaluate its prediction ability and VFS module in this study. The NSE and $R^2$ values for runoff estimation were 0.86 and 0.91, respectively, and measured and simulated sediment yield were 15.2 kg and 16.5 kg indicating this system, developed in this study, can be used to simulate runoff and sediment yield with acceptable accuracies. Nine VFS scenarios were evaluated for effectiveness of soil erosion reduction. Reduction efficiency of the VFS was high when sediment inflow was small. As shown in this study, this evaluation system can be used for evaluation BMPs with local rainfall intensity and variations considered with ease-of-use GIS interface.

• Land and Housing Review
• /
• v.7 no.2
• /
• pp.87-95
• /
• 2016

Housing benefits service that was implemented according to the National Basic Livelihood Security Act in 2002 has been changed with the enactment of "Housing benefits Law"(2014.1.24). Though the service was conducted for 13 years to improve the living environment of recipient households and create self-supporting jobs for low-income, there was a limit to ensure the efficiency due to variations in the administrative act and implementation in local governments. For that reason, the sales account and the profits of self-supporting enterprises and their cooperative in housing welfare sector that played a pivotal role had gone through many ups and downs and that is why the national coalition of self-supporting enterprises that were newly formed are forced to take self-effort and play a leading role for the improvement of future beneficiaries' satisfaction, namely to develop the level of service to keep the decent jobs consistent for low-income while responding institutional policy change and the demands for improving the home-amelioration system. Accordingly, this article has attempted to supplement existing research on housing-benefits service and determine how the field can keep pace with the new institutional environment. As a result, first, Central self-supporting enterprises provide high specialized-quality services to low-income families, second, central self-supporting enterprises induce to transition customized service agencies for improving the quality of residential housing benefits, Third, Housing self-supporting enterprises should correspondence with institutional change through the provision of explicit guidelines in relating to housing-service amelioration, the last, business practical process shall be accompanied by a consistent basis for innovative and procedural standards.