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Wear leveling techniques have been studied to prolong the lifetime of NAND flash memory. Most of studies have used Program/Erase(P/E) cycles as wear index for wear leveling. Unfortunately, P/E cycles could not predict the real lifetime of NAND flash blocks. Therefore, these algorithms have the limited performance from prolonging the lifetime when applied to the SSD. In order to apply the real lifetime, wear leveling algorithms, which use raw Bit Error Rate(rBER) as wear index, have been studied in recent years. In this paper, we propose CrEWL(Cold data identification using raw Bit error rate in Wear Leveling), which uses rBER as wear index to apply to the real lifetime. The proposed wear leveling reduces an overhead of garbage collections by using HBSQ(Hot Block Sequence Queue) which identifies hot data. In order to reduce overhead of wear leveling, CrEWL does not perform wear leveling until rBER of the some blocks reaches a threshold value. We evaluate CrEWL in comparison with the previous studies under the traces having the different Hot/Cold rate, and the experimental results show that our wear leveling technique can reduce the overhead up to 41% and prolong the lifetime up to 72% compared with previous wear leveling techniques.

In this paper, we present an color quantization method by complementing the disadvantage of K-means color quantization that is one of the well-known color quantization. We named the proposed method “octree-means” color quantization. K-means color quantization does not use all of the clusters because it initializes the centroid of clusters with random value. The proposed method complements this disadvantage by using the octree color quantization which is fast and uses the distribution of colors in image. We compare the proposed method to six well-known color quantization methods on ten test images to evaluate the performance. The experimental results show 68.29 percent of mean square error(MSE) and processing time increased by 14.34 percent compared with K-means color quantization. Therefore, the proposed method improved the K-means color quantization and perform an effective color quantization.

In this paper, we propose a modified fuzzy clustering algorithm which can overcome the center deviation due to the Euclidean distance commonly used in fuzzy clustering. Among fuzzy clustering methods, Fuzzy C-Means (FCM) is the most well-known clustering algorithm and has been widely applied to various problems successfully. In FCM, however, cluster centers tend leaning to high density clusters because the Euclidean distance measure forces high density cluster to make more contribution to clustering result. Proposed is an enhanced algorithm which modifies the objective function of FCM by adding a center-scattering term to make centers not to be close due to the cluster density. The proposed method converges more to real centers with small number of iterations compared to FCM. All the strengths can be verified with experimental results.

In this paper, we propose a method of glasses detection in facial image. we develop a detection method of glasses with a weighted sum of the results that detected by facial element detection and glasses frame candidate region. Component of the face detection method detects the glasses, by defining the detection probability of the glasses according to the detection of a face component. Method using the candidate region of the glasses frame detects the glasses, by defining feature of the glasses frame in the candidate region. finally, The results of the combined weight of both methods are obtained. The proposed method in this paper is expected to increase security system's recognition on facial accessories by raising detection performance of glasses or sunglasses for using ATM

In this paper, we propose the horizontal line detection using the Haar-like features and linear regression in infrared images. In the marine environment horizon image is very useful information on a variety of systems. In the proposed method Haar-like features it was noted that the standard deviation be calculated in real time on a static area. Based on the pixel position, calculating the standard deviation of the around area in real time and, if the reaction is to filter out the largest pixel can get the energy map of the area containing the straight horizontal line. In order to select a horizontal line of pixels from the energy map, we applied the linear regression, calculating a linear fit to the transverse horizontal line across the image to select the candidate optimal horizontal. The proposed method was carried out in a horizontal line detecting real infrared image experiment for day and night, it was confirmed the excellent detection results than the legacy methods.

In this paper, we propose the assistance method to enable safe driving through analysis of dangerous driving behavior using real-time alarm by vehicle speed, azimuth data and smartphone. For this method, smartphone is receiving driving data from digital tachograph using communication. Safe driving habit is a very important issue to commercial vehicle because that driver's long time driving than other vehicle type driver. Existing methods are very inefficient to improve immediately dangerous driving habits during driving because proceed driving behavior analysis after the vehicle operation. We propose the new safe driving assistance method that can prevent traffic accidents by real-time and improve the driver's wrong driving habits through real-time dangerous driving behavior analysis and notification the result to the driver. We have confirmed that the method in this paper will help to improve driving habits and can be applied through the proposed method implementation and simulation experiment

We propose a hybrid prefix caching scheme to enable high speed IP address lookup. All prefixes loaded in a prefix cache should not be overlapped in address range for correct IP lookup. So, every non-leaf prefix needs to be expanded not so as to be overlapped. The shorter expanded prefix is more preferable because it can cover wider address range just as an single entry in a prefix cache. We exploits advantages of two dynamic prefix expansion techniques, bounded prefix expansion technique and bitmap-based prefix expansion technique. The proposed scheme uses dual bound values whereas just one bound value is used in bounded prefix expansion. Our elaborated technique make the dual bound values be associated with several subtries flexibly using bitmap information, rather than with fixed subtries. We evaluate the performance of the proposed scheme in terms of the average length of the expanded prefixes and cache miss ratio. The experiment results show the proposed scheme has lower cache miss ratio than other previous schemes including both bounded prefix expansion and bitmap-based expansion irrespective of the cache size.

In this paper, we developed a Hospital Information System in which the business process is formalized and a wire/wireless integrated solution is used. This system consists of the administration office program, the medical office program, the ward management program and the rounds management program. The administration office program can enroll and accept patients, issue and reissue the RFID card. The medical office program inputs a medical examination and treatment, outputs a diagnosis, requests a hospitalization, retrieves the record of a medical examination and treatment, assigns the corresponding examination room to the accepted patients, and updates the number of an waiting patient and a patient number according to the examination room on real time. The ward management program handles hospitalizations and leaving hospital, a nurse's note, and an isolation ward monitoring. The rounds management program handles a medical examination and treatment, and a leaving hospital using PDA. This developed system can be built at low cost and increase the quality of the medical services highly by making it automated the medical administration automation. Also the small number of the medical staffs can manage the inpatients efficiently by using the monitoring functions.

In this paper, we draw a security assessment by analyzing possible vulnerabilities of the designated PC service which is supposed for strengthening security of current online identification methods that provide various areas such as the online banking and a game and so on. There is a difference between the designated PC service and online identification methods. Online identification methods authenticate an user by the user's private information or the user's knowledge-based information, though the designated PC service authenticates a hardware-based unique information of the user's PC. For this reason, high task significance services employ with online identification methods and the designated PC service for improving security multiply. Nevertheless, the security assessment of the designated PC service has been absent and possible vulnerabilities of the designated PC service are counterfeiter and falsification when the hardware-based unique-information is extracted on the user's PC and sent an authentication server. Therefore, in this paper, we analyze possible vulnerabilities of the designated PC service and draw the security assessment.

The heat conduction equation, a type of a Poisson equation which can be applied in various areas of engineering is calculating its value with the iteration method in general. The equation which had difference discretization of the heat conduction equation is the simultaneous equation, and each line has the characteristic of expressing in sparse matrix of the equivalent number of none-zero elements with neighboring grids. In this paper, we propose a data structure for sparse matrix that can calculate the value faster with less memory use calculate the heat conduction equation. To verify whether the proposed data structure efficiently calculates the value compared to the other sparse matrix representations, we apply the representative iteration method, CG (Conjugate Gradient), and presents experiment results of time consumed to get values, calculation time of each step and relevant time consumption ratio, and memory usage amount. The results of this experiment could be used to estimate main elements of calculating the value of the general heat conduction equation, such as time consumed, the memory usage amount.

Generally, the optimal solution of assignment problem can be obtained by Hungarian algorithm of two-sided optimization with time complexity O(n4) . This paper suggests one-sided optimal assignment and swap optimization algorithm with time complexity O(n2) can be achieve the goal of two-sided optimization. This algorithm selects the minimum cost for each row, and reassigns over-assigned to under-assigned cell. Next, that verifies the existence of swap optimization candidates, and swap optimizes with k-opt (k=2,3) . For 27 experimental data, the swap-optimization performs only 22% of data, and 78% of data can be get the two-sided optimal result through one-sided optimal result. Also, that can be improves on the solution of best known solution for partial problems.

In this paper, we propose a new method for multi transmission method of data among near smart devices. Existing methods require the use of an extra application service where the operating system differs between smart devices. In contrast, the proposed method makes use of the smart device’s inner speaker and microphone to confirm the transmission signal. Then, real sharing data is transmitted via WiFi or LTE. Therefore, the proposed method overcomes operating system issues with existing methods. Besides, BUMP technology works in a similar way to the method we propose, it only supports one-to-one transmission. To evaluate the efficacy of the new method, we tested one-to-many data transmission in an experiment: the results showed a 96% success rate. As a result, we believe that the proposed method is an effective multi transmission method of data among near smart devices.

In this paper, we introduce the application of several currently-representative methods for mineral resources potential assessment on Geographic information system(hereinafter referred to as GIS), and combined with mineral resources potential assessment performed in China and with lead–zinc deposits taken as an example, summarized and divided minerals prediction and assessment models; on this basis, this paper presented the process of metallogenic prognosis based on MRAS platform, and made a simple analysis on existing problems.

This paper suggests heuristic algorithm with polynomial time complexity for rigging elections problem that can be obtain the optimal solution using linear programming. The proposed algorithm transforms the given problem into adjacency graph. Then, we divide vertices V into two set W and D . The set D contains majority distinct and the set D contains minority area. This algorithm applies divide-and-conquer method that the minority area D is include into majority distinct W . While this algorithm using simple rule, that can be obtains the optimal solution equal to linear programing for experimental data. This paper shows polynomial time solution finding rule potential in rigging elections problem.

This study analyzed the effect of the factors of introducing information technology(organizational and environmental characteristics) on non-financial performance. As detailed variables of each characteristic, the technical support/task force, users' IT capability, and education/training were used for the organizational characteristics while the degree of competition, external pressure, and uncertainty of environment were used for the environmental characteristics. In the results of the analysis, such factors like technical support/task force, users' IT capability, and education/training of the organizational characteristics had significant influence on non-financial performance. Also, factors such as degree of competition, external pressure, and uncertainty of environment of the environmental characteristics had significant influence on non-financial performance.

This paper is a study on applications providing information related to infant care. It classifies various mobile contents into a few types, compares and contrasts them. Also it analyzes the latest trend of the contents and the strengths of newest applications or app. books. Through the analysis, this study suggests an infant care application which provides information efficiently. It causes useful that people in need can gather information conveniently through this application. Furthermore, it offers opportunities to contribute to the society.

This study was to analyze the employment needs of people with disabilities used Internet Knowledge Search for their employment. The questions related to employment of people with disabilities used Naver's Knowledge-iN Search during the year of 2014 to the year of 2015 were analyzed. The results are the follows. First, people with intellectual disabilities, mental disorders and physical disabilities asked many questions related to employment. Second, most minor disabilities asked many questions related to employment than severe disabilities but exception for people with mental disorders. Third, their's questions related to employment had some different but various according to the types of disabilities. Fourth, their's expected occupation had some different but various according to the types of disabilities. Implications for employment activation of people with disabilities were proposed.

In this paper, we propose a smartphone addiction affected adjustment to college life and the moderating effects of impulsivity in the relations between smartphone addiction and adjustment to college life. For this, it conducted the questionnaire with 348 college students who showed higher use of smartphone and analyzed the data from the questionnaire. The results of the analysis are as follows. It was found that smartphone addiction had significant influences on the adjustment to college life. As a result of examining the moderating effects of impulsivity in the relations between smartphone addiction and adjustment to college life, there were the moderating effects of impulsivity. This study was available in giving useful suggestions to prevent smartphone addiction and help college students adjust to their college life through impulsivity control.

This study is looking to do a new model which overcomes emotional isolation phenomenons of aged people through using an advanced technology in our community approaching an aging society. Senior welfare has been oriented to economically, medically supported welfare model so far. An ageing society going on, even if the scale of welfare cost is bigger and bigger, the level of satisfaction has been decreasing. This is the fact that the expansion of economical support for the aged in emotional alienation is not only a solution for them suffering from emotional isolation phenomenons ,which requires a new model for senior welfare. Above all, because the senior welfare oriented to economically, medically supported welfare model can not be continued any more, a new model is required to be sustainable in national finance. This study has a purpose that recovers emotional life of the aged, improves their quality of life , and offers emotional welfare model to be sustainable economically.

In this paper, a standardized phonological rule should be embodied for all people who want to use Hangul beyond nationality. This researcher suggested a phonological process protocol in unicode for the purpose of developing a computer system-based program as one of methods to pronounce Hangul correctly. First of all, to solve a problem of standardizing Hangul pronunciation, it is necessary to develop a phonological process system. In other words, when a mobile phone or a keyboard is used, inputted strings should be changed exactly by an automatic device made according to the phonological rule. For this, a phonological process table is the most important and unicode which digitalizes Hangul is the most effective. Therefore, the purpose of this study is to complete a phonological process table, suggest an algorithm by the table, and develop a computer program pursuing correct Hangul pronunciation. For the methodology of this study, the features of unicode was used to solve a problem of coding each syllable by phonemes after strings were inputted from the phonological process program. This study suggested a protocol that sounds of inputted strings were automatically changed via recombination using a phonological process table. The ultimate purpose of the study was to help pronounce Hangul correctly according to the pronunciation rule.

This study is intended to provide a basis for the planning of local governments to, analyzed in Gwangju Metropolitan City area D sixth regional health plans and Tertiary regional social welfare plans, establishing phase, the evaluation phase side. Based on the study results suggest the following implications. First, Specifically, it should be established to systematically planning process. Second, Plan's vision, key challenges, businesses are logical and details should be provided consistently. Third, It should be evaluated focusing on residents of the area change. Fourth, Change of plan indicators, performance indicators, etc. must be presented in detail.

Empirical studies of superior’s ethical leadership on organizational effectiveness of organization member have been done in various fields. However, it is difficult to find the previous research on civil servant in public sector. Therefore, the purpose of this study is to analyse causal relationship of ethical leadership and organizational effectiveness and to suggest theoretical and political implication for enhancing the level of civil servant’s organizational citizenship behavior. As the result of analysing the causal relationship of superior’s ethical leadership and organizational citizenship behavior, the factor of organizational effectiveness as the public attitude, this study shows that normative behavior, communication, reinforcement, and right decision-making have significant effect on organizational citizenship behavior. Based on these results, this study suggested theoretical and political implication and the limitations of study

Permutation p-values are provided for the agreement measures for multivariate interval data among many raters. Three agreement measures, Berry and Mielke's measure, Janson and Olsson's measure, and Um's measure are described and compared. Exact and resampling permutation methods are utilized to compute p-values and empirical quantile limits for three measures. Comparisons of p-values demonstrate that resampling permutation methods provide close approximations to exact p-values, and Berry and Mielke's measure and Um's measure show similar performance in terms of measuring agreement.

It is important to maintain information system (IS) following the business and institutional change. Even if successfully developed information systems, we cannot gain the benefit from the systems without the proactive maintenance activities. However, the importance of IS maintenance has not been considered as much as the system development, and we don’t have any specific performance management structure. The objective of this study is to identify the relationship between IS maintenance activities and utilization. For empirical test of the hypothesis model, the sample data is collected from public information system sites. Results from multiple regression analysis reveal that proactive maintenance activities including IS maintenance cost increase, improving functionality, and enhancing ease of use have a causal effect on the IS utilization.

In this paper, we propose a Science subject program based on programming learning to improve computational thinking ability in middle school. As the necessity of software education rises recently, the subject of information was designated as the mandatory subject in elementary, middle and high schools. In order to cultivate the ability that enables the leaners to search the knowledge in need by themselves and raise troubleshooting method, not the existing indoctrination, his thesis was willing to improve Computational Thinking ability and improve the ability of considering and thinking the matters by using scratch language. For that, this thesis developed and suggested science subject program that utilizes the programming learning.