• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.8
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• pp.2764-2782
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• 2021

Existing city-level boundary nodes identification methods need to locate all IP addresses on the path to differentiate which IP is the boundary node. However, these methods are susceptible to time-delay, the accuracy of location information and other factors, and the resource consumption of locating all IPes is tremendous. To improve the recognition rate and reduce the locating cost, this paper proposes an algorithm for city-level boundary node identification based on bidirectional approaching. Different from the existing methods based on time-delay information and location results, the proposed algorithm uses topological analysis to construct a set of candidate boundary nodes and then identifies the boundary nodes. The proposed algorithm can identify the boundary of the target city network without high-precision location information and dramatically reduces resource consumption compared with the traditional algorithm. Meanwhile, it can label some errors in the existing IP address database. Based on 45,182,326 measurement results from Zhengzhou, Chengdu and Hangzhou in China and New York, Los Angeles and Dallas in the United States, the experimental results show that: The algorithm can accurately identify the city boundary nodes using only 20.33% location resources, and more than 80.29% of the boundary nodes can be mined with a precision of more than 70.73%.

• Smart Structures and Systems
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• v.24 no.5
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• pp.617-630
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• 2019

Currently most of the vision-based structural identification research focus either on structural input (vehicle location) estimation or on structural output (structural displacement and strain responses) estimation. The structural condition assessment at global level just with the vision-based structural output cannot give a normalized response irrespective of the type and/or load configurations of the vehicles. Combining the vision-based structural input and the structural output from non-contact sensors overcomes the disadvantage given above, while reducing cost, time, labor force including cable wiring work. In conventional traffic monitoring, sometimes traffic closure is essential for bridge structures, which may cause other severe problems such as traffic jams and accidents. In this study, a completely non-contact structural identification system is proposed, and the system mainly targets the identification of bridge unit influence line (UIL) under operational traffic. Both the structural input (vehicle location information) and output (displacement responses) are obtained by only using cameras and computer vision techniques. Multiple cameras are synchronized by audio signal pattern recognition. The proposed system is verified with a laboratory experiment on a scaled bridge model under a small moving truck load and a field application on a footbridge on campus under a moving golf cart load. The UILs are successfully identified in both bridge cases. The pedestrian loads are also estimated with the extracted UIL and the predicted weights of pedestrians are observed to be in acceptable ranges.

• Journal of the Korean Society of Safety
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• v.24 no.5
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• pp.63-68
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• 2009

The urgent VAI method development is required since "The Act of Physical Protection and Radiological Emergency that is established in 2003" requires an evaluation of physical threats in nuclear facilities and an establishment of physical protection in Korea. The VAI methodology is developed to (1) make a sabotage model by reusing existing fire/flooding/pipe break PSA models, (2) calculate MCSs and TEPSs, (3) select the most cost-effective TEPS among many TEPSs, (4) determine the compartments in a selected TEPS as vital areas, and (5) provide protection measures to the vital areas. The developed VAI methodology contains four steps, (1) collecting the internal level 1 PSA model and information, (2) developing the fire/flood/pipe rupture model based on level 1 PSA model, (3) integrating the fire/flood/pipe rupture model into the sabotage model by JSTAR, and (4) calculating MCSs and TEPS. The VAT process is performed through the VIPEX that was developed in KAERI. This methodology serves as a guide to develop a sabotage model by using existing internal and external PSA models. When this methodology is used to identify the vital areas, it provides the most cost-effective method to save the VAI and physical protection costs.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.103-113
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• 2020

The construction industry is undergoing a digital transformation in which Building Information Modelling (BIM) is a key technology. The potential of BIM in several areas such as design optimization, time management, cost management, and asset management/facility management (AM/FM) is widely acknowledged by the AECO (Architecture, Engineering, Construction, and Operation) industry around the world. However, BIM implementation in construction projects is faced with problems such as project delay and cost overruns. The lack of identification of risks in BIM projects and standard guidelines on mitigation techniques furthers poor performance, dissatisfaction, and disputes between employers and project participants, which results in low BIM adoption rates. Therefore, the objective of this paper is to identify the potential risks in BIM implementation under the primary categories - (1) technical, (2) contractual, (3) management-related, and (4) personnel-related risks in BIM projects and present solutions to reduce, manage, and mitigate risks. To meet the objective of this paper, a survey was designed and conducted in the Hong Kong construction industry in which over 140 respondents from different disciplines, with experience in BIM projects, have participated. Based on the analysis of the survey data, the most severe and frequently occurring BIM risks and their potential mitigation strategies were identified and discussed in this paper.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.32 no.1
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• pp.28-38
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• 2024

Due to globalization, the air transport industry plays a key role in the global economy. In particular, the air transport industry is highly dependent on human resources, and the capabilities of the cabin crews in managing safety and providing service in a cabin depend on the service quality and the success of the company's human resource management. Therefore, systematic support and interest in competitive key personnel are believed as very important factors. Airlines need to improve the work engagement of airline cabin crew through organizational supportive efforts. Thus this paper surveyed 309 cabin crews who worked at low cost carrier and conducted an empirical analysis based on survey results. The study validates hypotheses pertaining the relationship between organizational identification and job commitment of cabin crew according to the airline's perception of organizational support. The comprehensive analysis reveals that perceived organization support has a significantly positive impact on cabin crews' work engagement.

• Journal of the Korean Operations Research and Management Science Society
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• v.30 no.2
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• pp.185-199
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• 2005

With the growth of internet shopping malls, there is increasing interest in comparison shopping mall. However most comparison sites compare only book prices by collecting simple XML data and do not provide .the exact comparison Including precise shipping costs. Shipping costs vary depending on each customer's address, the delivery method, and the category of selected goods, so rule based system is required in order to calculate exact shipping costs. Therefore, we designed and implemented comparison shopping mall which compares not only book prices but also shipping costs using rule based inference. By adopting the extensible Rule Markup language (XRML) approach, we proposed the methodology of extracting delivery rules from Web pages of each shopping mall. The XRML approach can facilitate nearly automatic rule extraction from Web pages and consistency maintenance between Web pages and rule base. We developed a ConsiderD system which applies our rule acquisition methodology based on XRML. The objective of the ConsiderD system is to compare the exact total cost of books including the delivery cost over Amazon.com, BarnesandNoble.com, and Powells.com. With this prototype, we conducted an experiment to show the potential of automatic rule acquisition from Web pages and illustrate the effect of delivery cost.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.66 no.3
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• pp.123-128
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• 2017

Electric utilities has been considered the necessity to introduce AM(asset management) of electric power facilities in order to reduce maintenance cost of existing facilities and to maximize profit. In order to make decisions in terms of repairs and replacements for power transformers, not only measuring by counting parts and labor costs, but comprehensive comparison including reliability and cost is needed. Therefore, this study is modeling input cost for power transformer during its entire life and also the life cycle cost (LCC) technique is applied. In particular, this paper presents an application of heuristic harmony search(HS) optimization algorithm to the convergence and the validity of economic life assessment of power transformer from LCC technique. This recently developed HS algorithm is conceptualized using the musical process of searching for a perfect state of harmony. It uses a stochastic random search instead of a gradient search so that derivative information is unnecessary. The effectiveness of the proposed identification method has been demonstrated through an economic life assessment simulation of power transformer using HS optimization algorithm.

• Journal of Korean Academy of Nursing
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• v.22 no.2
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• pp.185-206
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• 1992

In this study nursing activities were examined to determine the nursing cost. A professional nursing group developed a tool for the investigation. 128 nursing activities were identified by the tool in 16 nursing care areas as referenced in the literature. Each activity was examined for four essential factors to define nursing cost ; time consumed for the care, level of professional skill, degree of independency and performer of the care. The activity was rated by a five point Likert scale. This investigation was conducted with the nursing staffing working in the 21 university hospitals in Korea and having more than four years experience especially in medical or surgical wards. The participating nursing staff were screened on the basic of the recommendation of the nursing director. The data were gathered from June 12th to August 12th, 1989. All the data were analyzed for mean, standard deviation, percent, and correlation coefficients between items. The results are summarized as follows : 1. Direct nursing care was classified into 16 large areas and 128 small activities. 2. No significant correlation was found between the study items of each activity. 3. Among 128 nursing activities, Those performed less than 50% of the time by a nurse were excluded from the nursing cost. Also excluded activities which were given less than 9 marks in all three items, time consumed, level of professional skill, and degree of independency. As a result, 83 activities in 14 nursing care areas were selected for the proposal to estimate nursing cost.

• Structural Engineering and Mechanics
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• v.71 no.4
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• pp.391-405
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• 2019

Compared to the ambient vibration test mainly identifying the structural modal parameters, such as frequency, damping and mode shapes, the impact testing, which benefits from measuring both impacting forces and structural responses, has the merit to identify not only the structural modal parameters but also more detailed structural parameters, in particular flexibility. However, in traditional impact tests, an impacting hammer or artificial excitation device is employed, which restricts the efficiency of tests on various bridge structures. To resolve this problem, we propose a new method whereby a moving vehicle is taken as a continuous exciter and develop a corresponding flexibility identification theory, in which the continuous wheel forces induced by the moving vehicle is considered as structural input and the acceleration response of the bridge as the output, thus a structural flexibility matrix can be identified and then structural deflections of the bridge under arbitrary static loads can be predicted. The proposed method is more convenient, time-saving and cost-effective compared with traditional impact tests. However, because the proposed test produces a spatially continuous force while classical impact forces are spatially discrete, a new flexibility identification theory is required, and a novel structural identification method involving with equivalent load distribution, the enhanced Frequency Response Function (eFRFs) construction and modal scaling factor identification is proposed to make use of the continuous excitation force to identify the basic modal parameters as well as the structural flexibility. Laboratory and numerical examples are given, which validate the effectiveness of the proposed method. Furthermore, parametric analysis including road roughness, vehicle speed, vehicle weight, vehicle's stiffness and damping are conducted and the results obtained demonstrate that the developed method has strong robustness except that the relative error increases with the increase of measurement noise.

• The KIPS Transactions:PartD
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• v.9D no.1
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• pp.91-102
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• 2002

We need a component-based system to reflect software changes in user's requirements, to implement a system at a rapid speed as well as to efficiently manage the system in a maintenance phase and to easily change software. Moreover, the component-based system has a merit in development cost. However, existing component development methodology for implement of component-based system is inefficient in object identification for component identification. Moreover, the existing component development methodology also fails to provide any method to identify system component. It merely provides procedures and methods to identify business component focused on a whole system domain. In addition, it has another problem that it considerably relies on developer's experiences and intuitions for component identification. Therefore, according to this paper, RUP (Rational Unified Process) is applied from a requirement analysis phase to an object identification phase in order to improve the inefficiency of object identification. In addition, this paper procedures and methods for system component identification, and identifies business components based on the identified system component, rather than on the whole system domain. This paper also provides and applies cohesion metric and coupling metric so as to overcome the problem that component identification depends on developer's intuitions and experiences. Accordingly, the component identification method proposed in this paper, may identify components more effectively based on facility of object identification, functional reusability of components, traceability, and independence of components.