• Journal of information and communication convergence engineering
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• 제18권2호
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• pp.94-99
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• 2020

Real cyberterrors are invisible and difficult to identify. Even after a cyberattack, its origin and cause are difficult to determine. Cyberterrorism results in invisible cyberwars, and it is believed that World War IV will begin with a cyberwarfare. For national cybersecurity, information on cybersecurity must be collected, shared, and disseminated. In this study, we investigate a blockchain system designed based on the World Cybersecurity Agreement. National cybersecurity information is linked to the hyperledger blockchain system network through the National Cybersecurity Center. National cybersecurity information designs and uses a secure protocol for protection; further, it is collected, shared, and disseminated to treaty countries. National cybersecurity information is shared and spread by the hyperledger blockchain system, and it uses a cyberdefense system that responds to the cyberattacks and their origin. This paper serves as a policy and legislation guideline for forming a World Cybersecurity Agreement between countries.

• Nuclear Engineering and Technology
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• 제52권4호
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• pp.856-862
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• 2020

Defect inspection system for industrial applications takes the important portion. Non-destructive inspection method has been significantly improved. Infrared thermography, as one of method for non-destructive inspection, can provide relatively precise data and quick inspection time. This study, it was performed to measure defect according to the measurement limit of the non-visible areas such as the back surface of the pipe using reflection plate using reflection plate based on Infrared thermography. The materials of the reflection plate were determined in consideration of the space limitation and the thermal characteristics, and defects were detected by the manufactured reflection plate. Detection of defect in non-visible area using the candidate materials for reflection plate was conducted.

• 한국과학교육학회지
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• 제10권2호
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• pp.11-24
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• 1990

The objectives of this study are to find out the research methodology about misconception, the types of scientific concepts to be misconcepted the analysis methodology of causes of misconception, and remediation methodology of misconception. The research methods of this study are descriptive ques tionnare, interview, classroom observation and curriculum analysis. The results of this study are: ${\circ}$ The descriptive questionnaire is sufficient to obtain children's ideas. ${\circ}$ The types of science concepts to be misconcepted are 'the invisible natural phenomena,' 'the vague Understanding', 'the contents of teachers' lecture', 'the lack of children's cognitive development,'and 'the influence of nursery stories.' ${\circ}$ The Cause analysis methods of misconception are that the analysis of the cognitive level of the questionnaire items, the examining the item concepts are taught or not and the investigation about the agreement of the cognitive level of the questionnaire item and children. ${\circ}$ Remediation methods are visualijation and instrustion of invisible natural phenomena, concrete presentation of the scientific concepts, and acceleration of the cognitive development.

• 디지털산업정보학회논문지
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• 제5권4호
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• pp.161-168
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• 2009

There are many research for efficient, robust and invisible watermarking system that protects the digital contents like a image and animation according to growth of IT industry. First of all, frequency domain watermarking system like DWT(Descrete Wavelet Transform) is excellent because of minimum loss of original image and robustness of external attack. But, if we raise the insertion strength of watermark, then blazing of image occurs on existing DWT watermarking system and we should have a regular square image. In this study, we research the overflow check for preventing image from blazing and a robust and invisible watermarking algorithm. And we research a free-size DWT watermarking system using padding bytes, without a dependency of size.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.1701-1706
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• 2004

FRT design aims at high-tech vehicles of high efficiency and cleanness, it must materialize the meaning and role as new added value by applying car design aesthetics of a new future-oriented concept. In addition, different from ordinary vehicle design, FRT involves invisible factors such as pleasantness, safety, accessibility, controllability, movability, conveniency, culture, identity, brand image and fashionableness. Because FRT vehicles are transportation means used by various groups of people, they must be approached with the barrier-free design concept. Therefore, in order to enhance the potential of future transportation culture emphasizing creativity based on diversity, it is important to establish core design factors that create new added values and to apply new concepts to their roles.

• 전자공학회논문지S
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• 제35S권4호
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• pp.85-95
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• 1998

In this paper, a new watermarking method for a copy protectionof images is proposed. The proposed method adaptively embeds a watermark in the frequency domain of images using human visual system model. For this purpose, the Just Noticeable Differences(JNDs) of each frequency coeffeicient value of a luminance plane is first found using Watson and Solomon's visual system model. An invisible maximum watermark value with is different in every position according to the characteristics of images is determined usig JND and Minkowski metric. A low frequency domain is divided into two sets based on a PN-sequence to protect thewatermark from the attack. The watermarks are added to one set of coefficients and detecting a watermark, the difference between the mean values of absolute coefficient values of both sets is calculated. The embedded watermark is tested using statistical hypothesis based on test static dertermined by the ean difference. To demonstrate the perfromance of the proposed method, the new watermarking method is applied to a high frequency image and low frequency images. Experimenatal results show the watermark is invisible and robust to JPEGlossy compression and noise.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.845-848
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• 2007

Analysis of point defects invisible by a microscope has been studied on the a-Si thin film transistor panel. The point defects which were named Invisible Point Defect (IPD) is characterized by no particles or distortion of patterns on a pixel structure and randomly distributed on panels. To investigate the IPD, measurements were carried out: gray level driving, transistor transfer characteristic, focused ion beam (FIB), and secondary ion mass spectrometry (SIMS). The results showed that a contamination layer had a bad influence on an active surface. The contamination layer consisted of oxygen and iron from a water supply line during cleaning process. After the process tuning, IPD has been stabilized.

• 한국가정과학회지
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• 제3권2호
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• pp.47-57
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• 2000

We study on the housewives'social contribution through their household labor. By the method of literature review, we discuss about the housewives'social roles, their negative problems and the private and public efforts to solve the problems, and ultimate direction to the solutions. We find their four roles-Invisible labors In this capitalist society. consumers without any sovereignty, substitutes for incomplete social welfare system and agents to develop and sustain the social network. A few solutions which they have found out or the Korean society has devised are not enough. The utmost and ultimate solutions should include the housewives'autonomy. subjectivity and community.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.631-633
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• 2003

Invisible networks have hidden bits flows from human being and become the periphery in the Internet overload; technologies become invisible and everywhere computing. The appearance of the calm environment requires a new relationship between human being and machines and geographic features: a paradigm shift. However no one says what next steps to those environments on details are, a reason why lots of people focus on the endeavors. In this paper, we touch the geographic features on ubiquitous environments and research the transition step of GIS mobile applications in order to achieve a natural integration of connectivity, capability and functionality.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.24-27
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• 2005

The NDT(Non-Destructive Testing) is valid fur the defect detection of rolling stocks because it can be used to detect defects in invisible places. For example, in case of wheelsets fatigue cracks are initiated in the wheel seat that suffers from fretting fatigue damage. But the conventional ICFPD method can not be applied to detect such cracks in press-fit area of the axle by some technical problems. In this study, we introduced a new ICFPD (Induced Current Focusing Potential Drop) method that can be applied in press-fit area of the axle. And we performed the finite element analysis of the new ICFPD method using measured electromagnetic properties of the wheel and axle. It seems that our approach is very useful f3r the detection of defects in invisible places.