• Korean Journal of Construction Engineering and Management
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• v.18 no.3
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• pp.22-32
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• 2017

Judging from the past cases, the contractor has frequently suffered losses caused by disapproved requests or reduced payments since it has not known the conditions of the contract or it has filed a claim to the owner without any proper claim system. Therefore, the existing claim process needs to be reformed. In order to reform the claim process, the contractor should consolidate the organizational structure, grant accurate duty assignments to the claims manager, implement regular staff training on how to deal with claims. In addition to this reformation, the contractor needs to improve the management of construction period and process control, and manage related documents thoroughly. Regular meetings are also necessary in claims. This study attempts to prove the effectiveness of the reformed process applied to Project "A", where the owner was responsible for the delayed supply of materials, inaccurate oral instructions, insufficient information on the work, and frequent changes of design. The project was completed in 96 months, which was extended by 34 months from the initial construction period of 62 months. The reformed claim process is expected to be of great help not only to largescale construction works but also to smallscale ones.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3D
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• pp.441-450
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• 2011

Recent construction projects consist of large and complex facilities, which project management information system (PMIS) is used for managing construction cost and schedule. The ministry of land, transport and maritime affairs (MLTM) is using a continuous acquisition and life-cycle support (CALS) system for managing the public construction projects. This study attempts to survey some problems of the CALS system in practical application, and then suggests the new functions to improve practical application of the CALS system. All functions in each menu were analyzed in the practical application aspect. All projects ordered from MLTM should use the CALS system as a PMIS, but the practical application is limited in partial functions and special working group. And the utilization of system is focused on simple tasks and report process. One of main reason is that the system is using numerical data rather than graphical data. This study suggests new functions and a visualized management method that can improve the practical applicability using a 4D object in each current functions.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.3
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• pp.56-63
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• 2015

Several fields of science have demanded large-scale workflow support, which requires thousands of CPU cores or more. In order to support such large-scale scientific workflows, high capacity parallel systems such as supercomputers are widely used. In order to increase the utilization of these systems, most schedulers use backfilling policy: Small jobs are moved ahead to fill in holes in the schedule when large jobs do not delay. Since an estimate of the runtime is necessary for backfilling, most parallel systems use user's estimated runtime. However, it is found to be extremely inaccurate because users overestimate their jobs. Therefore, in this paper, we propose a novel system for the runtime prediction based on workload-aware clustering with the goal of improving prediction performance. The proposed method for runtime prediction of parallel applications consists of three main phases. First, a feature selection based on factor analysis is performed to identify important input features. Then, it performs a clustering analysis of history data based on self-organizing map which is followed by hierarchical clustering for finding the clustering boundaries from the weight vectors. Finally, prediction models are constructed using support vector regression with the clustered workload data. Multiple prediction models for each clustered data pattern can reduce the error rate compared with a single model for the whole data pattern. In the experiments, we use workload logs on parallel systems (i.e., iPSC, LANL-CM5, SDSC-Par95, SDSC-Par96, and CTC-SP2) to evaluate the effectiveness of our approach. Comparing with other techniques, experimental results show that the proposed method improves the accuracy up to 69.08%.

• Journal of dental hygiene science
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• v.20 no.1
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• pp.25-33
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• 2020

Background: This study investigated the status of oral health promotion activities for adult workers in public health centers and industrial dental offices and provided basic data for the model development of oral health promotion program for adult workers in Korea. Methods: A questionnaire was developed separately according to the person who in charge of the oral health promotion activities in public health centers nationwide and dental hygienists working in 20 industrial dental offices. This survey was conducted through postal survey and consisted of 29 items and 35 items respectively, including 19 common items for general information, oral health promotion program status and opinion. Statistical analysis was performed using the IBM SPSS ver. 23.0. Results: We analyzed the data of 147 public health centers (57.9%) and 9 industrial dental offices (45.0%). A workforce with a lack of practice was the biggest barrier to oral health promotion activities for adult workers. However, both groups showed high intention for the practice of adult worker's oral health promotion activities. Also, they showed willingness to work together in an organic partnership to perform their roles (94.4% and 77.8%, respectively). Regarding the scope of cooperation in the implementation of the industrial oral health promotion activity linked to the public health center, dental hygienists of industrial dental offices responded that they could coordinate necessary matters and schedule management. Conclusion: The development of an oral health promotion program aided by the relationship between public health centers and industrial dental offices is essential for the oral health promotion of adult workers. The possibility of cooperation between the abovementioned centers was confirmed through this study. In a long-term perspective, it would be necessary to identify a method to institutionalize industrial dental hygienists for the provision of continuous oral health care in workplaces.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.5
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• pp.31-38
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• 2000

We propose a new photorefractive demultiplexer(DMUX) which can select the 16 channel signal in WDM optical communication system using the wavelength selectivity and the demultiplexing property through multiple recording of holographic volume grating in photorefractive Fe-LiNbO$_{3}$ crystal. For the multiple writing of the 16 channels having uniform diffraction efficiency, the rotation multiplexing technique and the exposure time schedule are used. Designed DMUX has the 16 channels with 0.5nm spacing between 670nm and 677.5nm and the bandwidth of 0.16nm. From the experimental results, the diffraction efficiency of each channel is 8.3 $\pm$0.62%, the optical loss from fresnel reflection and absorption on the crystal is 0.4cm-1, the 3㏈ bandwidth is 0.16 $\pm$0.005nm and the channel spacing is 0.46~0.5nm.

• Journal of Convergence for Information Technology
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• v.7 no.6
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• pp.209-218
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• 2017

To propose a contents model for children's smart watch, this study interview 15mothers who have a child using smart watches. Most mothers purchase smart watches for children to warrant their security and manage their schedules, and they use them for sending a call or text to their children, tracking or managing children's location and schedule. Mothers were satisfied with a smart watch's function of communication and safety management, but dissatisfied learning-oriented contents and worrried about bad influenced on children development. Through in-depth interviews, this study propose a persona model for children's smart watch for enhancing parent-child interaction and physical cognitive language socioemotional convergence play contents.

• Land and Housing Review
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• v.1 no.1
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• pp.9-17
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• 2010

Due to the variety of processes that are mainly influenced by the modification of law and regulations, it is difficult to propose a formal procedure of urban renewal projects. In addition, conflicts among various participants and stake-holders have made urban renewal difficult to manage. Needs for new systems to support management of this type of projects have been raised. This system should enable users to manage program aspects as well as projects given that the urban renewal consists of several projects. According to analysis of current context, the requirements of the system are classified as follows: a method to create flexible systems to cope with various process; functions to provide data on cost and schedule; user-friendly visualized tools enhancing understand of non-experts or less-experienced participants. This paper summarizes the background, requirements, concept and model of the system. Currently, prototype systems have been developed. Regarding outputs presented so far, potential benefits of the system are presented as well.

• Convergence Security Journal
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• v.11 no.1
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• pp.39-48
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• 2011

QoS(Quality of Service) is defined "The collective effect of service performance which determines the degree of satisfaction of a user of the service" by ITU-T Rec. E.800. The final goal of information system is to secure the performance efficiency within the required time. The security QoS framework is the modeling of the QoS measurement metrics, the measurement time schedule, instrument, method of measurement and the series of methodology about analysis of the result of measurement. This paper relates to implementing issue and performance measuring about blended mechanism between networking technology and security technology. We got more effectiveness in overall network security, when applying and composing amalgamated security mechanism between network technology and security technology. In this paper, we suggest techniques being used on infrastructure system and also offers a security QoS methodology as a model of more effective way. Methodology proposed in this research has proven that it is possible to measure response time through the scheduled method.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.467-476
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• 2014

According to the expanding of construction machinery works, the number of civil complaints demanding compensations are increasing continuously from surrounding residents due to the noise from construction fields. However, the noise is usually managed restrictedly during the construction phase rather than prevented in advance. So, the efforts to solve the noise problem are occurring only after complaints have been made. Also, excessive cost and time consuming in order to solve the complaints negatively affects to construction companies. Therefore, the purpose of this study is to develop an optimized scheduling process model for controlling the noise in construction field by considering the planned time, cost, and the number of equipment before construction. In addition, this process model is expected to provide a useful information about the cost comparison between the original planned cost plus compensation and the optimized cost considering noise limitation so that the site managers can manage their projects effectively.

• Journal of Communications and Networks
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• v.17 no.2
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• pp.184-197
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• 2015

This paper builds on a recent method, chain routing with even energy consumption (CREEC), for designing a wireless sensor network with chain topology and for scheduling the communication to ensure even average energy consumption in the network. In here a new suboptimal design is proposed and compared with the CREEC design. The chain topology in CREEC is reconfigured after each group of n converge-casts with the goal of making the energy consumption along the new paths between the nodes in the chain as even as possible. The new method described in this paper designs a single near-optimal Hamiltonian circuit, used to obtain multiple chains having only the terminal nodes different at different converge-casts. The advantage of the new scheme is that for the whole life of the network most of the communication takes place between same pairs of nodes, therefore keeping topology reconfigurations at a minimum. The optimal scheduling of the communication between the network and base station in order to maximize network lifetime, given the chosen minimum length circuit, becomes a simple linear programming problem which needs to be solved only once, at the initialization stage. The maximum lifetime obtained when using any combination of chains is shown to be upper bounded by the solution of a suitable linear programming problem. The upper bounds show that the proposed method provides near-optimal solutions for several wireless sensor network parameter sets.