• IE interfaces
• /
• v.24 no.4
• /
• pp.373-378
• /
• 2011

High level of accuracy in forecasting heat demand of each district is required for operating and managing the district heating efficiently. Heat demand has a close connection with the demands of the previous days and the temperature, general demand forecasting methods may be used forecast. However, there are some exceptional situations to apply general methods such as the exceptional low demand in weekends or vacation period. We introduce a new method to forecast the heat demand to overcome these situations, using the linearities between the demand and some other factors. Our method uses the temperature and the past 7 days' demands as the factors which determine the future demand. The model consists of daily and hourly models which are multiple linear regression models. Appling these two models to historical data, we confirmed that our method can forecast the heat demand correctly with reasonable errors.

• International Journal of Advanced Culture Technology
• /
• v.2 no.1
• /
• pp.1-13
• /
• 2014

In next-generation wireless networks, provisioning of IP-based network architecture and seamless transmission services are very important issues for mobile nodes. For this reason, a mobility management mechanism to support global roaming is highly regarded. These technologies bring a broader life by using a global roaming account through the connection of multiple devices or technology to mobile users; they also provide real-time multimedia services. This paper presents a comprehensive performance analysis of fast handover for hierarchical mobile IPv6 (F-HMIPv6), hierarchical mobile IPv6 (HMIPv6), Proxy Mobile IPv6 (PMIPv6), and fast Proxy Mobile IPv6 (FPMIPv6) using the fluid-flow model and random-walk model. As a result, the location update cost of the PMIPv6 and FPMIPv6 is better than that of HMIPv6 and F-HMIPv6. These results suggest that the network-based mobility management technology is superior to the hierarchical mobility management technology in the mobility environment.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.41 no.1
• /
• pp.127-143
• /
• 2016

This study applied DEA analysis to measure the relative efficiency of 35 companies that produce automobile body components. First, the input and output, the improvement target value of the calculated variables, and the reference group for benchmarking for inefficient groups to become efficient groups were established through DEA analysis. In addition, whether inefficiency was due to technical inefficiency or size was analyzed in connection with the cases of the actual companies through the measurement of scale efficiency. Second, a route for efficiency improvement was derived through DEA-Tier analysis by defining the possible group for benchmarking in actuality within the production industry of automobile body components where the primary cooperative company belonged. Third, the financial variables that generate the difference between efficient and inefficient groups were derived through logistic regression analysis. Financial strategies that determine the direction the indices should be improved to allow the inefficient group to become an efficient one were recommended. This research is expected to provide diagnostic methods for management efficiency and the direction of improvement to enhance the management efficiency of automotive parts makers by identifying the causes of the inefficiency of domestic automotive parts makers empirically. The study also provides financial strategies together with the target values of efficiency improvement for each individual company.

• Journal of Digital Convergence
• /
• v.9 no.2
• /
• pp.53-63
• /
• 2011

In connection with each other through social networks, individuals share valuable knowledge and information. Furthermore the knowledge and information based on the collective intelligence is growing. Collective intelligence with more peoples will grow by gathering intelligence to enhance the collective intelligence. This study investigates the collective intelligence using business management game, and observes forming process of collective intelligence. To achieve the objective to observe the forming process of collective intelligence, only the test subjects available were exposed to the Corporate Management Game with SNS space. During the experimentation, the interaction and feedback were observed. The results of the study show that different performance, feedback and interaction for each group.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.5 no.3
• /
• pp.288-293
• /
• 2010

In these information-communication society, the wireless system technologies are increasing to do all things with wireless solution for fast and convenient works. This trend drives ubiquitous solutions which are based on broadband wireless network that gives network connection whenever, everywhere. This paper deals a bookshelf management system using plower line communication and RFID module. This system includes a 900 MHz RFID reader, Passive RFID-Tags, an Atmeg128 microprocessor board attached LED Display Module, and a management PC with GUI Software. This system works well in power line communication, tag reading and LED display, and PC Management Software.

• Environmental Engineering Research
• /
• v.15 no.1
• /
• pp.29-33
• /
• 2010

In 2004, the Korean government launched comprehensive measures for nonpoint pollution that were intended to reduce their amount by 34.3% over of those forecast by 2020. During the first and second stages of their implementation; from 2004 to 2011, nonpoint source (NPS) measures have focused on systemic improvements and project management, as well as the introduction of optimal management techniques; accordingly, reductions have been small. However, during the third stage in 2011, serious reductions will be pursued. Accordingly, the gradual expansion of sites subject to NPS measures has focused on the establishment of a basis for reduction measures in connection with model projects during the first half of the plan, with full scale enforcement due in the second half. For Korea, rather than commencing NPS management en masse, it has been more appropriate to gradate NPS management into stages tailored to the different needs of new and existing businesses, as well as to the needs of large and small-scale businesses, in consideration of their specific circumstances. This has allowed sufficient time for such businesses to become accustomed to the concept of NPS management.

• International conference on construction engineering and project management
• /
• 2017.10a
• /
• pp.192-200
• /
• 2017

With the acceleration of construction industrialization, the buildings that China has adopted the construction of industrialization technology are increasing day by day, and Precast Concrete (PC) Structure technology is one of the main technologies of construction industrialization. Compared with the traditional cast-in-place concrete structure, PC structure is more conducive to shorten the construction period, reduce the number of construction workers and the site construction waste. Nevertheless, PC structure improves the requirements of hoisting machinery in the construction site, and the lay-out and selection of hoisting machinery become an important factor influencing the construction cost. The paper regards the typical tower crane in China as the research object, and establishes the time optimization model for the lifting scheme. The influence of the different precast rate on the selection of the tower crane is analyzed. This paper obtains the time variation of the tower crane under different precast rate, provides a theoretical basis for the design of precast concrete structures under the influence of assembly construction, and lays the foundation for the selection of tower crane under the precast rate.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.10 no.6
• /
• pp.53-62
• /
• 2011

Although the demand of Variable Message Sign(VMS) has become pervasive in fulfilling the ITS policy, there are still several unsolved problematic issues. The most critical ones of them are inequality and inefficiency of providing traffic information. This paper proposes the Infra-free Variable Message Sign in order to provide useful informations such as road condition, weather, and traffic of the area, where constructing the infrastructure of communication and power supply is relatively very hard. First of all, the characteristics of infra-free Variable Message Sign are studied and analyzed in deep because of differences between normal Variable Message Sign and Infra-free Variable Message Sign in the configuration and the operating method due to the nature of the Infra-free Variable Message Sign. Futhermore, for effective power management of operating Infra-free Variable Message Sign with limited power acquired through stand-alone PV system, new battery connection structure and dynamically variable power managements for the differently shown messages on Variable Message Sign are proposed. The proposed structure in this paper can be applied to not only power management for Infra-free Variable Message Sign but also power management for the various applications using parallel connection battery system.

• Korean Security Journal
• /
• no.3
• /
• pp.83-116
• /
• 2000

Many concerns have been raised for importance of disaster management after 1990's numerous urban disasters in Korea. When the primary function of government is to protect lives and property of citizens, disaster management should be included in the mainstream of public administration and many hazard countermeasures should be carried out for that purpose. The principal purpose of this research is to establish ways and means needed to improve the disaster management system in Korea. This paper is split into five chapters. Chapter I is the introduction part. Chapter II introduces the reader to a disaster management theory, and deals with various disaster management systems of foreign countries such as the U.S.A. and Japan, Chapter III describes and characterizes the Korea's current disaster management system. The Korean disaster management system has been reestablished through the enactment of the Disaster Management Act of 1995 and the full revision of Natural Hazards Management Act of 1995 after series of catastrophic man-made disasters since 1993. Chapter IV is devoted to the establishment of an effective disaster management system in Korea. In this chapter, I discusses measures needed to improve the quality of CDMB(Central Disaster Management Bureau)'s service to the people. I strongly reemphasize the effectiveness of a comprehensive risk-based, all-hazard national emergency management system that addresses preparedness, mitigation, response, and recovery. To that end the Administration should develop legislation, new policies, and organizational plans to invigorate the agency with a refocussed mission. Chapter V is a conclusion. As the demand for citizens'welfare has been continuously increased in the localization, the importance of disaster management is emerging subject in the public sector. The disaster management carries out complicated affairs and manages diverse objects, the cooperation/connection system of the central-local government and citizens, and non-governmental organization should be established.

• Journal of the Korea Institute of Building Construction
• /
• v.2 no.1
• /
• pp.155-162
• /
• 2002

In this research, I finally came to a conclusion analyzing the connection among managing of each items in management expenses, the size of each complex and stories, and the term of using. (1) In the managing cost regarding to the management manner, although the managing cost of self-governing management is less imposed than the one of commission management, there is slight difference between those Costs. And it is more important to consider the effectiveness of management than to emphasize reduction of management cost. (2) The higher the stories, the higher the managing cost of elevator per the unit area. It Is caused by the fact that the father the distance of the elevator operating, the higher the electric charges. (3) The third of one of total management cost goes to pay the personnel expenses. So I found that the effective management of the expenses is available to reduce management cost. (4) The higher the stones, the lower the cost of personnel expenses including the cleaner cost. (5) The sum of costs assigned in repairment and management increases in proportion to the term of using. The costs assigned in special repairment and management are interacting to each other. (6) To reduce the management cost, we have to cut down the personnel in security guard that occupies one third of total management cost with application to the joint security system and operation of the self-governing guard. Through this process, it will be easy to accomplish the rationalization of contract with an outside order. Because the improvement of management service is not only the responsibility of owner but also the one of dwellers. And it Is imperative to realize the importance of cooperation and trust between the owner and dwellers. And the establishment of effective managing system which has convenience and rationality must be settled without delay.