• Water Engineering Research
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• 제5권1호
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• pp.47-54
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• 2004

Several computer programs have been developed to make stochastically generated weather data from observed daily data. But they require fully dataset to run WGEN. Mostly, meterological data frequently have sporadic missing data as well as totally missing data. The modified WGEN has data filling algorithm for incomplete meterological datasets. Any other WGEN models have not the function of data filling. Modified WGEN with data filling algorithm is processing from the equation of Matalas for first order autoregressive process on a multi dimensional state with known cross and auto correlations among state variables. The parameters of the equation of Matalas are derived from existing dataset and derived parameters are adopted to fill data. In case of WGEN (Richardson and Wright, 1984), it is one of most widely used weather generators. But it has to be modified and added. It uses an exponential distribution to generate precipitation amounts. An exponential distribution is easier to describe the distribution of precipitation amounts. But precipitation data with using exponential distribution has not been expressed well. In this paper, generated precipitation data from WGEN and Modified WGEN were compared with corresponding measured data as statistic parameters. The modified WGEN adopted a formula of CLIGEN for WEPP (Water Erosion Prediction Project) in USDA in 1985. In this paper, the result of other parameters except precipitation is not introduced. It will be introduced through study of verification and review soon

• Journal of Information Processing Systems
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• 제13권4호
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• pp.668-676
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• 2017

Recently, the importance of big data has been emphasized with the development of smartphone, web/SNS. As a result, MapReduce, which can efficiently process big data, is receiving worldwide attention because of its excellent scalability and stability. Since big data has a large amount, fast creation speed, and various properties, it is more efficient to process big data summary information than big data itself. Wavelet histogram, which is a typical data summary information generation technique, can generate optimal data summary information that does not cause loss of information of original data. Therefore, a system applying a wavelet histogram generation technique based on MapReduce has been actively studied. However, existing research has a disadvantage in that the generation speed is slow because the wavelet histogram is generated through one or more MapReduce Jobs. And there is a high possibility that the error of the data restored by the wavelet histogram becomes large. However, since the wavelet histogram generation system based on the MapReduce developed in this paper generates the wavelet histogram through one MapReduce Job, the generation speed can be greatly increased. In addition, since the wavelet histogram is generated by adjusting the error boundary specified by the user, the error of the restored data can be adjusted from the wavelet histogram. Finally, we verified the efficiency of the wavelet histogram generation system developed in this paper through performance evaluation.

• 한국컴퓨터정보학회논문지
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• 제24권3호
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• pp.159-166
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• 2019

The collection and manipulation of Internet of Things (IoT) data is increasing at a fast pace and its importance is recognized in every sector of our society. For efficient utilization of IoT data, the vast and varied IoT data needs to be reliable and meaningful. In this paper, we propose an IoT framework to realize this need. The IoT framework is based on a four layer IoT architecture onto which context aware computing technology is applied. If the collected IoT data is unreliable it cannot be used for its intended purpose and the whole service using the data must be abandoned. In this paper, we include techniques to remove uncertainty in the early stage of IoT data capture and collection resulting in reliable data. Since the data coming out of the various IoT devices have different formats, it is important to convert them into a standard format before further processing, We propose the RDF format to be the standard format for all IoT data. In addition, it is not feasible to process all captured Iot data from the sensor devices. In order to decide which data to process and understand, we propose to use contexts and reasoning based on these contexts. For reasoning, we propose to use standard AI and statistical techniques. We also propose an experiment environment that can be used to develop an IoT application to realize the IoT framework.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권10호
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• pp.3419-3437
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• 2022

Anonymization technology is an important technology for privacy protection in the process of data release. Usually, before publishing data, the data publisher needs to use anonymization technology to anonymize the original data, and then publish the anonymized data. However, for data publishers who do not have or have less anonymized technical knowledge background, how to configure appropriate parameters for data with different characteristics has become a more difficult problem. In response to this problem, this paper adds a historical configuration scheme resource pool on the basis of the traditional anonymization process, and configuration parameters can be automatically recommended through the historical configuration scheme resource pool. On this basis, a privacy model hybrid recommendation algorithm for user satisfaction is formed. The algorithm includes a forward recommendation process and a reverse recommendation process, which can respectively perform data anonymization processing for users with different anonymization technical knowledge backgrounds. The privacy model hybrid recommendation algorithm for user satisfaction described in this paper is suitable for a wider population, providing a simpler, more efficient and automated solution for data anonymization, reducing data processing time and improving the quality of anonymized data, which enhances data protection capabilities.

• 한국전자거래학회지
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• 제1권1호
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• pp.117-140
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• 1996

CALS is recognized as a national response to the new chapter of information society. It is essential that the standardization in Korea should be constructed compatible with not only domestic but also international standardization trend. This study aims to propose a proper direction of CALS standardization in Korea, based on the international CALS standardization movement. This paper classifies standard into five types and provides a proper direction and guidance far each standard. As a trend of CALS standard, all ten data files are converted using SGML standard far the interchangeability of data among heterogenous systems. CAD and Graphic data arc also moving toward to the STEP as their standard. In this regard, this paper discusses how to implement SGML and STEP Model. Finally, this paper proposes a method how to construct an EDI system with CALS standard and how to establish a standard authorization institute which will be responsible far the standard authorization. Furthermore, this paper also proposes the CALS Test Network (CTN) as its experimental method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.101-104
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• 2002

This paper propose that is algorithm of power dissipation reduction in the high level synthesis design for DSP(Digital Signal Processor), as the portable terminal system recently demand high power dissipation. This paper obtain effect of power dissipation reduction and switching activity that increase correlation of operands as input data of function unit. The algorithm search loop or repeatedly data to the input operands of function unit. That can be reduce the power dissipation using the new low power high level synthesis algorithm. In this Paper, scheduling operation search same nodes from input DFG(Data Flow Graph) with correlation coefficient of first input node and among nodes. Function units consist a multiplier, an adder and a register. The power estimation method is added switching activity for each bits of nodes. The power estimation have good efficient using proposed algorithm. This paper result obtain more Power reduction of fifty percents after using a new low power algorithm in a function unit as multiplier.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.1151-1156
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• 2002

This paper describes the examples of Noise, Vibration and Harshness(N.V.H) development applying Computer Aided Engineering(CAE). Some Commercial Software was used to reduce the cost, development time and to predict the Noise and vibration phenomenon of new vehicle design. This paper is including measured and analysis data, and tried to prove the good correlation between measured and calculated data, so test and analysis data were compared seriously and carefully. Analysis models, which were used to predict and develop the NVH phenomenon, analysis method, and a field of --0application are explained briefly. Also, model pictures are presenting in this paper. This paper describes the analyzing method of the calculated results, design modification and development procedure, and NVH performance target setting up and procedure.

• Smart Structures and Systems
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• 제30권3호
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• pp.263-271
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• 2022

In this paper we present an overview of damage diagnosis algorithms that have been developed over the past two decades using vibration signals obtained from structures. Then, the paper focuses primarily on algorithms that can be used following an extreme event such as a large earthquake to identify structural damage for responding in a timely manner. The algorithms presented in the paper use measurements obtained from accelerometers and gyroscope to identify the occurrence of damage and classify the damage. Example algorithms are presented include those based on autoregressive moving average (ARMA), wavelet energies from wavelet transform and rotation models. The algorithms are illustrated through application of data from test structures such as the ASCE Benchmark structure and laboratory tests of scaled bridge columns and steel frames. The paper concludes by identifying needs for research and development in order for such algorithms to become viable in practice.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제11권2호
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• pp.51-58
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• 2022

블록체인 기술은 블록체인 네트워크에 참여하는 사용자의 데이터가 분산 처리되어 저장되는 시스템이다. 비트코인과 이더리움을 필두로 세계적으로 관심을 받고 있으며, 블록체인의 활용성은 무궁무진한 것으로 예측되고 있다. 하지만 블록체인의 모든 데이터를 네트워크 참여자에게 공개하는 투명성으로 인해 블록체인 데이터 프라이버시 보호에 대한 필요성이 개인정보를 처리하는 각종 금융, 의료, 부동산 분야에서 떠오르고 있다. 기존 블록체인 데이터 프라이버시 보호를 위해서 스마트 컨트랙트, 동형암호화, 암호학 키 방식을 사용하는 연구들이 주를 이루었으나, 본 논문에서는 기존의 논문들과 차별화된 매트릭스 문자 재배치 기법을 사용한 데이터 프라이버시 보호를 제안한다. 본 논문에서 제안하는 접근방안은 원본 데이터를 매트릭스 문자 재배치 하는 방법, 배치된 데이터를 다시 원본으로 되돌리는 방법, 크게 두 가지로 구성이 되어있다. 정성적인 실험을 통해 본 논문에서 제안하는 접근방안의 안전성을 평가하였으며, 매트릭스 문자 재배치가 적용된 데이터를 원본 데이터로 되돌릴 때 걸리는 시간을 측정하여 프라이빗 블록체인 환경에서도 충분히 적용이 가능할 것이라는 것을 증명하였다.

• 정보기술과데이타베이스저널
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• 제6권2호
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• pp.101-114
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• 1999

Data Naming has been a long-lived issue in data management. A data name is a basic vehicle to convey meanings of data. Thus, names are organized in such a way that anyone can understand their meanings with ease; however, Korean data names have been organized based on English-like naming scheme. This paper proposes a Korean data naming scheme. For this, we specify information that data names should include. Secondly, we propose rules to organize data names. For real world applications, a database system is proposed to manage data names. The database is expected to provide a starting point that on organization can develop its own data name repository.