• Journal of Digital Convergence
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• v.14 no.11
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• pp.241-247
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• 2016

As a domestic traffic control signal system, either the system with which a traffic signal turns into green at regular intervals or the system with which an amber or a red signal flickers on local roads without heavy traffic at midnight has been utilized. However, when the former system is used for roads with light traffic at midnight, delays and congestion can be incurred. Besides, in case of the latter signal system, the risk of vehicle crash is high. This study proposes a response type of flickering green signal system that rearranges signal system after analyzing beacon messages including sensor data. The proposed system, on a trunk road or a branch road at midnight, makes the signal keep flickering in green; When a vehicle enters the range of RSE, the transfer coverage, it transmits beacon messages regularly and Agent System analyzes the messages and alters the signal. It is a system by which vehicles move following the altered signal system, which will not only ensure smooth flow but also prevent vehicles from crashing on a road with light traffic. As a result of a simulation, traffic throughput and the average waiting time displayed 10 to 30 percent better improvement than existing signal systems, in terms of performance.

• Informatization Policy
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• v.25 no.3
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• pp.3-28
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• 2018

The purpose of this study is to analyze the research trends and present future research directions in the field of Cyber Physical System (CPS), a key element in the 4th Industrial Revolution, Industry 4.0, and Smart Manufacturing that are currently promoted as important innovation agenda both at home and abroad. In this study, (1) the concepts of industry 4.0, smart manufacturing and CPS are summarized; (2) analysis criteria of these fields are established; and 3) analysis results are presented and future research direction is proposed. 74 overseas and 8 domestic literature on manufacturing CPS from 2013 to 2017 are identified through 'Google Scholar Search'. Major results of the analysis are summarized as follows: (1) research on a common methodology and framework for the manufacturing CPS needs to be done based on the analysis of the existing methodologies and frameworks of various perspectives; (2) in order to improve the maturity of the manufacturing CPS, it is necessary to study actual deployment and operations of CPS, including the existing systems; (3) it is necessary to study the diagnostic methodology that can evaluate manufacturing CPS and suggest improvement strategy; and (4) as for the detailed model and tool, it is necessary to reinforce research on SCM production planning and human-machine collaboration while considering the characteristics of CPS.

• Journal of Digital Convergence
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• v.12 no.5
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• pp.213-220
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• 2014

The purpose of this present study is to empirically analyze the variables affecting socio-economic performance of social enterprises. For this purpose of 107 enterprises, located in Seoul, was performed under the hypothesis that the authentication properties (authentication type, authentication year) of social enterprises will affect the socio-economic performance. The analysis showed that first; authentication type among the characteristics of social enterprises showed significant effects on the social performance. Second, authentication year among the characteristics of social enterprises showed significant effects on the economic performances. In addition, since the job-creating type showed higher social performance, it would be desirable to raise the certification rate of this type in the future. The analysis implied that longer the years of accreditation, the greater positive effects on the socio-economic performance of social enterprises was shown. Therefore, the present study suggest the need to diversify support policies according to the number of authentication years in order to secure sustainability by maximizing the socio-economic performance of social enterprise because the monolithic support is not very effective for continued growth and self-reliance of social enterprises.

• Child Health Nursing Research
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• v.19 no.1
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• pp.59-68
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• 2013

Purpose: This study was conducted to identify current health care management and barriers in health care management according to ecological systems, and to develop an ecological model for enhancing health care in child care centers. Methods: Focus group interviews were conducted with directors and teachers of child care centers, and with parents of children enrolled in child care. Data were analyzed by the latent content analysis method. Results: Twelve categories of health care management were identified. Barriers to child health care included knowledge deficit and lack of competence in health care by teachers, lack of useful health care manuals, non-existence of professional child health care personnel in child care centers, lack of mutual information sharing and disagreement on child health conditions between child care personnel and parents, lack of specific health related child care inspection criteria and time flexible child care centers with a lack of policy on collaboration with health care facilities. The ecological model developed included specific strategies to improve health care management in child care. Conclusion: The proposed ecological model to improve child health care management should be useful to plan future health care program considering both the immediate and indirect social environment surrounding children in child care.

• Korean Journal of Construction Engineering and Management
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• v.14 no.2
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• pp.184-193
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• 2013

Procurement System for Korean construction industry has mainly been controlled by the complicated regulatory system which has been recognized as unflexible and remotely separated from the global standard. This has been identified by many Korean construction experts as one of the main reasons that hamper the Korean construction industry becoming the global leader. One commonly discussed regulatory system is the compulsory multiple contracting system that has been enforced for a long time. According to the Korean governmental contracting law 68-3, all construction projects cannot be divided into separate contracting packages with a few exceptions. Exceptions stated in the law include construction activities related electrical, Information communication, fire-fighting, and cultural assets which all are governed by the separate laws/acts controlled by the different governmental bodies. This research is to closely investigate multiple prime contracting system that has been compulsory in Korean construction industry and to provide policy recommendations to these restrictions. Although, there has been a long history of this compulsory contracting system, this study attempted to provide objective analysis on current status of the system as well as global standard on the issue. This study suggests main considerations when considering different contracting system such as rights of owners, flexibilities of regulatory systems, and efficiencies of conducting a construction project. It is envisioned that recommendations from this study, if accepted by the regulatory bodies, would improve the Korean construction contraction system by making it more compatible with global standard. Moreover, these would help making the Korean industry more effective in terms of regulatory restrictions.

• Journal of Digital Convergence
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• v.12 no.10
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• pp.201-209
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• 2014

The purpose of this study is to analyze subjective and objective factors for the successful operation of One-Person Creative Firms and find significant variables in accordance with the sales and net profit that are representing business performances. Additionally, we were trying to find that what One-Person Creative Firms have had a government assistance need the supports in order to achieving a good performance in sales and net profit. In the result of this study, the sales volume is related that two(2) subjective(Judgment, Planning) and four(4) objective factors(Patent Application, Patent Registration, Business Duration, Initial Capital). The net profit is related that Challenging Spirits in subjective factors and Run-up to the Business, Business Duration, Initial Capital in objective factors. Ultimately, these factors are important variables for the sales and net profit in relationship both the positive(+) and negative(-). This is an exploratory nature of the study rather than the rigorous hypothesis testing. Therefore, a rigorous hypothesis test study model to derive a more detailed study is needed based on the results of this study in the future.

• The KIPS Transactions:PartA
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• v.19A no.1
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• pp.35-44
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• 2012

Traditional technologies that are used to improve the performance of hard disk drives show many negative cases if they are applied to solid state drives (SSD). Access time and block sequence in hard disk drives that consist of mechanical components are very important performance factors. Meanwhile, SSD provides superior random read performance that is not affected by block address sequence due to the characteristics of flash memory. Practically, it is recommended to disable prefetching if a SSD is installed in a personal computer. However, this paper presents a combinational method of a prefetching scheme and a memory management that consider the internal structure of SSD and the characteristics of NAND flash memory. It is important that SSD must concurrently operate multiple flash memory chips. The I/O unit size of NAND flash memory tends to increase and it exceeded the block size of operating systems. Hence, the proposed prefetching scheme performs in an operating unit of SSD. To complement a weak point of the prefetching scheme, the proposed memory management scheme adaptively evicts uselessly prefetched data to maximize the sum of cache hit rate and prefetch hit rate. We implemented the proposed schemes as a Linux kernel module and evaluated them using a commercial SSD. The schemes improved the I/O performance up to 26% in a given experiment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.737-743
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• 2021

In this paper, the current status of marine industrial facilities, regulatory legal systems, and emission status of hazardous and noxious substances (HNS) in these facilities were analyzed, and the direction of improvement of the regulatory system was presented accordingly. As a result of the analysis, it is estimated that about 1,100 marine industrial facilities are subject to the Marine Environment Management Act of 2007. It is estimated that 190 kinds of hazardous substances are discharged from these marine industrial facilities and are highly likely to flow into the ocean, of which 20 are estimated to be discharged into the water system. However, due to the lack of relevant laws and regulation, it is difficult to clearly determine whether the discharged material corresponds to an exceptional discharged material, making it difficult to effectively enforce regulations in the field. For this reason, effective regulatory enforcement is difficult in the regulatory field. The marine environment management law should clearly stipulate the exceptional emission standards and types of substances, and clarify the selection system, risk assessment system, and emission information collection and monitoring system for related Hazardous and Noxious Substances.

• 한국사회정책
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• v.25 no.1
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• pp.161-194
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• 2018

The purpose of this study is to investigate the factors that interrupt the use of social security of elderly North Korean refugees. As a result of qualitative content analysis using interview data, it is found that the elderly North Korean defectors have a lower access to the social security system. The main reason for hindering the use of social security system is low awareness due to limited information channels, psychological distance to South Korean society and residents. Moreover, this psychological distance is a factor that reduces the geographical accessibility of elderly North Korean defectors by preferring to use services in specific institutions for North Korean, while South Korean elderly people can use the service elsewhere. In addition, there are many cases in which the elderly in North Korean defectors do not receive sufficient social security due to low income. On the other hand, social security systems with high accessibility of older North Korean refugees are characterized by the fact that they are provided by experts who have formed sufficient rapport with North Korean refugees. Therefore, it seems possible to improve the accessibility of elderly defectors' friendly system by professional workers with cultural competence. In addition, a multidimensional approach is needed to fully cope with the complex desires of elderly North Korean defectors and a mechanism should be set up to reflect their opinion in system operation.

• KIPS Transactions on Computer and Communication Systems
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• v.8 no.1
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• pp.17-28
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• 2019

In the financial investment management strategy, the distributed investment selecting and combining various financial assets is called portfolio management theory. In recent years, the blockchain based financial assets, such as cryptocurrencies, have been traded on several well-known exchanges, and an efficient portfolio management approach is required in order for investors to steadily raise their return on investment in cryptocurrencies. On the other hand, deep learning has shown remarkable results in various fields, and research on application of deep reinforcement learning algorithm to portfolio management has begun. In this paper, we propose an efficient financial portfolio investment management method based on Asynchronous Advantage Actor-Critic (A3C), which is a representative asynchronous reinforcement learning algorithm. In addition, since the conventional cross-entropy function can not be applied to portfolio management, we propose a proper method where the existing cross-entropy is modified to fit the portfolio investment method. Finally, we compare the proposed A3C model with the existing reinforcement learning based cryptography portfolio investment algorithm, and prove that the performance of the proposed A3C model is better than the existing one.