• Journal of the Korea Institute of Building Construction
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• 제13권5호
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• pp.498-505
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• 2013

The main processes involved in a defect dispute are consulting, reviewing, and finally judging as an arbiter. This process of defect consulting produces a defect consulting report, but business practices and standards of judgment will differ among consultants, and have many problems. This study reviews the structure of a defect consulting report and considers the structure's problem, which is that it is not standardized. To achieve this, data of sixteen defect consulting report were collected involving defect lawsuit cases before or after 2010. The structure and index of the defect consulting reports were then reviewed, and the results are as follows. As for a structure based on fourteen index, there are suitable that judge a outline, a cost estimate data and a consulting work item by a consulting standard. Furthermore, analysis by each common parts and private parts is considered as appropriate about consulting items and estimate by standard. However, consulting item in construction progress and responsibility period for security that related on a cause and a responsibility of defect need to complement. Meanwhile, the first thing of issues are connected a defect consulting is urgent a standardization for a defect type.

• Structural Engineering and Mechanics
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• 제63권6호
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• pp.751-760
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• 2017

In recent years, multifractal-based analysis methods have been widely applied in engineering. Among these methods, multifractal detrended cross-correlation analysis (MFDXA), a branch of fractal analysis, has been successfully applied in the fields of finance and biomedicine. For its great potential in reflecting the subtle characteristic among signals, a structural health monitoring (SHM) system based on MFDXA is proposed. In this system, damage assessment is conducted by exploiting the concept of multifractal theory to quantify the complexity of the vibration signal measured from a structure. According to the proposed algorithm, the damage condition is first distinguished by multifractal detrended fluctuation analysis. Subsequently, the relationship between the q-order, q-order detrended covariance, and length of segment is further explored. The dissimilarity between damaged and undamaged cases is visualized on contour diagrams, and the damage location can thus be detected using signals measured from different floors. Moreover, a damage index is proposed to efficiently enhance the SHM process. A seven-story benchmark structure, located at the National Center for Research on Earthquake Engineering (NCREE), was employed for an experimental verification to demonstrate the performance of the proposed SHM algorithm. According to the results, the damage condition and orientation could be correctly identified using the MFDXA algorithm and the proposed damage index. Since only the ambient vibration signal is required along with a set of initial reference measurements, the proposed SHM system can provide a lower cost, efficient, and reliable monitoring process.

• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.621-631
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• 2017

In this paper, we study the various impacts of connecting distributed generation (DG) to the distribution network. The comprehensive evaluation index system (CEIS) of four hierarchies is established, considering economy, reliability and voltage quality, and the calculation methods of different indexes are presented. This paper puts forward an improved triangular fuzzy number analytic hierarchy process (ITFNAHP) to weight the second level indexes (SLI) and the third level indexes (TLI), and calculates the variation coefficient to weight the fourth level indexes (FLI). We calculate the comprehensive weight coefficients based on the weight coefficients of the SLI, TLI and FLI, and then calculate the comprehensive evaluation of satisfaction (CES) of different access schemes. On the basis of the IEEE 33-bus example system, simulations of the calculation methods and the comprehensive evaluation method are carried out under different DG access schemes according to the same total investment cost and the same permeability, respectively, and the simulation results are analyzed and discussed.

• Journal of Korean Biological Nursing Science
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• 제12권1호
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• pp.1-7
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• 2010

Purpose: This research is to promote an walking exercise program for the subjects to continue exercise by mitigating stresses with increase in increase their physiological index. Methods: The research design was a non-equivalent control group, quasiexperimental study. The research has been executed from August 1st to September 30th 2008 by operating walking exercise program to 50 subjects. Only 24 patients who continued this program to the last were could be investigated. Results: Among the subjects who participated in the program had shown significant differences in weight and BMI. Despite of an insignificant change in skeletal muscle mass, fat mass, body fat ratio and WHR, average value for skeletal muscle mass showed an increasing tendency, while the average values for fat mass, body fat ratio and WHR showed a decreasing tendency. Conclusion: In conclusion, walking exercise program was design for the subjects to be able to exercise without an extra cost for a special tool to exercise with an positive effect on increasing health problem.

• The Journal of Information Technology and Database
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• 제7권2호
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• pp.47-59
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• 2000

In this paper, we analyze the applicability of a general optimization algorithm to a database optimization problem. The index selection problem Is the problem to choose a set of indexes for a database in a way that the cost to process queries in the given workload is minimized subject to a given storage space restriction for storing indexes. The problem is well known in database research fields, and many optimization and/or heuristic algorithms have been proposed. Our work differs from previous research in that we formalize the problem in the form of non-linear Integer Programming model, and investigate the feasibility and applicability of a general purpose optimization algorithm, called OPBDP, through experiments. We implemented algorithms to generate workload data sets and problem instances for the experiment. The OPBDP algorithm, which is a non-linear 0-1 Integer Programming problem solver based on Davis-Putnam method, worked generally well for our problem formulation. The experiment result showed various performance characteristics depending on the types of decision variables, variable navigation methods and ocher algorithm parameters, and indicates the need of further study on the exploitation of the general purpose optimization techniques for the optimization problems in database area.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• 제22권3호
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• pp.459-464
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• 2013

The purpose of a micro-mixing device is to enhance the mixing by increasing the diffusion effect between different types of flows. There have been many attempts to actively or passively increase mixing. However, those studies were limited to lab-scale experiments because the production of devices requires a series of processes, time, cost, and the mixing quality itself. For this reason, this study attempted to develop a quick and simple process for micro-mixing device fabrication by using conventional machining and bonding processes and applying ultrasonic waves from the outside of the mixing device. The mixing quality was quantified by using the mixing index, and the results showed that the proposed system increases the mixing from ~33% to ~10% with respect to the flow rates.

• Journal of Electrical Engineering and Technology
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• 제8권5호
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• pp.991-1001
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• 2013

Instead of building new substations or transmission lines, proper installation of flexible AC transmission systems (FACTS) devices can make the transmission networks accommodate more power transfers with less expansion cost. In this paper, the problem to maximize power system loadability by optimally installing two types of FACTS devices, namely static var compensator (SVC) and thyristor controlled series compensator (TCSC), is formulated as a mixed discrete-continuous nonlinear optimization problem (MDCP). To reduce the complexity of the problem, the locations suitable for SVC and TCSC installations are first investigated with tangent vector technique and real power flow performance index (PI) sensitivity factor and, with the specified locations for SVC and TCSC installations, a set of schemes is formed. For each scheme with the specific locations for SVC and TCSC installations, the MDCP is reduced to a continuous nonlinear optimization problem and the computing efficiency can be largely improved. Finally, to cope with the technical and economic concerns simultaneously, the scheme with the biggest utilization index value is recommended. The IEEE-14 bus system and a practical power system are used to validate the proposed method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권11호
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• pp.5692-5716
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• 2019

One of the best means to safeguard the confidentiality, security, and privacy of an image within the IoT-Cloud is through encryption. However, looking through encrypted data is a difficult process. Several techniques for searching encrypted data have been devised, but certain security solutions may not be used in IoT-Cloud because such solutions are not lightweight. We propose a lightweight scheme that can perform a content-based search of encrypted images, namely EEIRI. In this scheme, the images are represented using local features. We develop and validate a secure scheme for measuring the Euclidean distance between two descriptor sets. To improve the search efficiency, we employ the k-means clustering technique to construct a searchable tree-based index. Our index construction process ensures the privacy of the stored data and search requests. When compared with more familiar techniques of searching images over plaintexts, EEIRI is considered to be more efficient, demonstrating a higher search cost of 7% and a decrease in search accuracy of 1.7%. Numerous empirical investigations are carried out in relation to real image collections so as to evidence our work.

• Journal of Computing Science and Engineering
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• 제3권1호
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• pp.1-4
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• 2009

In a given text T of size n, we need to search for the information that we are interested. In order to support fast searching, an index must be constructed by preprocessing the text. Suffix array is a kind of index data structure. The compressed suffix array (CSA) is one of the compressed indices based on the regularity of the suffix array, and can be compressed to the $k^{th}$ order empirical entropy. In this paper we improve the lookup time complexity of the compressed suffix array by using the multi-ary wavelet tree at the cost of more space. In our implementation, the lookup time complexity of the compressed suffix array is O(${\log}_{\sigma}^{\varepsilon/(1-{\varepsilon})}\;n\;{\log}_r\;\sigma$), and the space of the compressed suffix array is ${\varepsilon}^{-1}\;nH_k(T)+O(n\;{\log}\;{\log}\;n/{\log}^{\varepsilon}_{\sigma}\;n)$ bits, where a is the size of alphabet, $H_k$ is the kth order empirical entropy r is the branching factor of the multi-ary wavelet tree such that $2{\leq}r{\leq}\sqrt{n}$ and $r{\leq}O({\log}^{1-{\varepsilon}}_{\sigma}\;n)$ and 0 < $\varepsilon$ < 1/2 is a constant.

• Journal of Digital Contents Society
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• 제3권1호
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• pp.11-22
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• 2002

The purpose of this study was to develop indicators for information and communication technology(ICT) use in elementary education, which are useful tools for forecasting and deciding the policy of education in the society of information technology. We analyzed prior studies on information and communication indicators, and suggested a survey forms to collect data and an equation for each indicator in order to calculate an index from the data without additional survey-cost. They can be intended to be explored on definitions of ICT use in education, indicators for ITC use in elementary education, illustration of utilizing the indicators, and an analysis of differences among schools on the indicators.