• Journal of the Korean institute of surface engineering
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• v.51 no.3
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• pp.185-190
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• 2018

Dopant-free silicon heterojunction solar cells using Transition Metal Oxide(TMO) such as Molybdenum Oxide($MoO_X$) and Vanadium Oxide($V_2O_X$) have been focused on to increase the work function of TMO in order to maximize the work function difference between TMO and n-Si for a high-efficiency solar cell. One another way to increase the work function difference is to control the silicon wafer resistivity. In this paper, dopant-free silicon heterojunction solar cells were fabricated using the wafer with the various resistivity and analyzed to understand the effect of n-Si work function. As a result, it is shown that the high passivation and junction quality when $V_2O_X$ deposited on the wafer with low work function compared to the high work function wafer, inducing the increase of higher collection probability, especially at long wavelength region. the solar cell efficiency of 15.28% was measured in low work function wafer, which is 34% higher value than the high work function solar cells.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.10 no.1
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• pp.21-29
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• 2006

The method to construct a surface from point data are widely known. But the way to make a surface from derivative data is not usually used since derivative data in engineering appears very often. In this paper, if more than one types of data among three possible data such as point data, first derivative data, second derivative data are given, we can construct a surface. If only first derivative data are given, we add a function value at the one point. If only second derivative data are given, we add a linear function.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8C
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• pp.756-764
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• 2003

We investigate a probabilistic public key cryptosystem proposed by Paillier. It is based on the discrete logarithmic function and the messages are calculated from the modular product of two those functions, one of which has a fixed value depending on a given public key. The improvement is achieved by a good choice for the public key so that it is possible to get efficient schemes without losing the onewayness and semantic security. Also we suggest the method to get the public key for our schemes.

• Journal of Korea Multimedia Society
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• v.11 no.6
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• pp.845-851
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• 2008

The ID/password method is the most classical method among authentication techniques on the internet, and is performed more easily and successfully than other methods. However, it is a vulnerable method against attacks such as eavesdropping or replay attack. To overcome this problem, OTP technique is used. The most popular OTP is HOTP algorithm, which is based on one-way hash function SHA-1. As recent researches show the weakness of the hash function, we need a new algorithm to replace HOTP. In this paper we propose a new OTP algorithm using the MAC(Message Authentication Code) based on AES. We also show that the new OTP outperforms HOTP experimentally.

• Korean Journal of Child Studies
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• v.37 no.6
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• pp.19-33
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• 2016

Objective: This study aimed to examine the prospective links among perspective taking, attachment security, and executive function and the mediating role of executive function on the relationship between attachment security and perspective taking. Methods: The participants included 147 preschoolers living in Gyeonggi. The data-analysis methods included descriptive statistics, independent t-tests, one-way ANOVAs, Pearson's correlation analysis, hierarchical multiple regression analysis, and the Sobel test. Results: First, preschoolers' perspective taking was significantly related to attachment security, and executive function. Furthermore, there was a significant association between attachment security and executive function. As expected, the correlations were positive in all cases. Second, the effects of attachment security on intention and emotion perspective takings were fully mediated by executive function when holding children's age and vocabulary constant. However, executive function did not predict thought perspective taking, whereas attachment security did. Conclusion: Given that parent-child attachment security might play an important role in child cognitive and socio-cognitive development, parents' endeavors to enhance the quality of the attachment relationship could be a fruitful path for preschoolers' developing executive capacities and perspective taking.

• The Transactions of the Korea Information Processing Society
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• v.6 no.1
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• pp.225-233
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• 1999

One of the reasons that debugging distributed programs is much more difficult than sequential programs is the communication among processes. Even though there are many debuggers constructed on distributed system environment, no available debugger provides an efficient way to debug communication events.. In this paper, we show the way to debug RPC communication, which is regarded as one of the most popular communication protocol in distributed system development. This paper presents the implementation of the RPC event trace function based on the RPC event model, which is proposed to accommodate communication events into debugging objects. Analyzing conventional RPC protocols, we formalized library function calls as corresponding actions to sending and receiving of messages. B recognizing the locations of library calls the debugger can detect all occurrences of communication events, This RPC event trace function is implemented on the on-line distributed debugger UniVIEW system.

• 한국디지털정책학회:학술대회논문집
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• 2006.06a
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• pp.379-390
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• 2006

For the domestic digital contents, it is particularly important that the planning and mediating functions should cover the whole industries so that in order for dividends and assistance to reach all the way back to the primary contents-creating level, where economic risks are especially high. A proactive cooperation system or framework between the government, the businesses and research institutions, which would allow for free flow of interaction among these players, can play that role. We can broadly define cooperation frameworks into two; one between the central and the local governments and one among private-sector groups, such as companies, associations and groups. These player sin the framework have differing, sometimes, conflicting views regarding the digital contents industry whether the digital contents should aim for skilled applicability or the abstract or whether the emphasis should rest on public interest or profitability. Immature competition and lack of trust among these players also give rise to such inefficiencies as overlap in investments, inexpertness and inefficient use of resources. We have proposed and realized the National Integrated Cooperation System to bridge these gaps among the major players in the industry. The National Integrated Cooperation System rests on the following major functions. The first major function of the NICS is to decipher any ambiguity that may be embedded in external inputs by stratified role and bias. The second function is to create cooperative groups that will deal with the ambiguities based on its consequent situation. The third is a feedback function that will draw out a new cooperative way by re-feeding the capacities and the conflicts that stem from the existing organizations and strategies into cooperation and adjustment process. Our NICS has compared and evaluated with England and Australia digital content industry models under AHP(Analytic Hierarchy Process) method. NICS has turned out to be well designed and have strong points based on OECD innovation and cooperation criteria.

• The KIPS Transactions:PartC
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• v.9C no.1
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• pp.1-8
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• 2002

Digital image watermarking is a technique for the purpose of protecting the ownership of the image by embedding proprietary watermarks in a digital image. It is required for the digital image watermarking scheme to pursue the robustness against water marking attacks and the perceptual Invisibility more than usual in steganography area, to guarantee not a hidden watermarking algorithm but the publicity of water-marking algorithm details and hidden use of key, which can protect the unauthorized user access from detection. In this paper we propose a new copyright watermarking scheme, which is barred on one-way hash functions using ElGamal functions and modular operations. ElGamal functions are widely used in cryptographic systems. Our watermarking scheme is robust against LSB(least significant bit) attacks and gamma correction attack, and also perceptually invisible. We demonstrate the characteristics of our proposed watermarking scheme through experiments. It is necessary to proceed as the future work the algorithm of achieving at the same time both the pseudo-randomness for the steno-key generation and the asymmetric-key generation.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.5
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• pp.957-962
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• 2016

Current terrestrial Digital Multimedia Broadcasting (T-DMB) is conducting the emergency alert broadcast, or can view a variety of broadcasting. However, propagation shadow area is a situation where the service is limited due to limitations of facilities investment. In addition, there is the problem of T-DMB broadcasting is for viewing only a restricted area and a mobile device because the mobile is also T-DMB viewing device impossible. In this paper, it receives a T-DMB broadcasting as a way to solve the problems of the T-DMB system, which was studied the re transmission to the mobile device. Accordingly, by receiving the broadcast may be watched in the mobile device the T-DMB reception impossible. Also provides a one-way/two-way authentication mechanism using a conditional access function, and the system was configured so that the user can watch only the registered broadcasting.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.10
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• pp.1608-1618
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• 2008

This research was conducted to define the different conventional meanings of face painting, we can come across easily in recent days, in different times and different cultures. The conclusions of the research are as followed. First, the face painting was mainly done for the symbolic function. Second, in un-cultivated groups, face painting was one way of body art expression and in some cases, the color and the pattern was the tool to give a symbolic massage that was more powerful than a language. The characteristics of the patterning was that they adopted wide range of patterns include geriatrics, abstract, animals, plants and especially the abstract patterns have the groups unique symbolic meanings such as specific pattern appears guard god which was the effort of having a wholeness with the pattern. Third, it is known that in un-cultivated cultures, face painting has a symbolic function whereas in modern society, there is an emphasis on a decorative function. Lastly, the various expressions of modern body decorations are seen as a result of social/cultural states of the settlement ethnic culture and the modern life style of the people who want to have direct and active opinions and individualize and differentiate themselves.