KJC Korea
Journal Central

In multi-core processors, Last Level Cache(LLC) can reduce the speed gap between the memory and the core. For this reason, LLC has big impact on the performance of processors. LLC is composed of shared cache and private cache. In computer architecture community, most researchers have mainly focused on the management techniques for shared cache, while management techniques for private cache have not been widely researched. In conventional private LLC, memory is statically assigned to each core, resulting in serious performance degradation when the workloads are not fairly distributed. To overcome this problem, this paper proposes the replacement policy for managing private cache of LLC efficiently. As proposed core-aware cache replacement policy can reconfigure LLC dynamically, hit rate of LLC is increases drastically. Moreover, proposed policy uses 2-bit saturating counters to improve the performance. According to our simulation results, the proposed method can improve hit rates by 9.23% and reduce the access time by 12.85% compared to the conventional method.

The goal of this paper is to provide performance improvement and stability for satellite data correction of some distortions due to cloud or radiance through distributed processing on cluster. To do this, we proposed and implemented SGE(Sun Grid Engine) based distributed processing methods using local storages and a status table. In the verification, the experiment result revealed that the proposed system on seven nodes improved the processing speed by 138.81% as compare to the existing system and provided good stability as well. This result showed that the proposed distributed processing work is more appropriate to process CPU bound jobs than I/O bound jobs. We expect that the proposed system will give scientists improved analysis performance in various fields and near-real time analysis services.

In this paper, we propose pre-arrangement based task scheduling scheme to reduce MapReduce job processing time. If a task and data to be processed do not locate in same node, the data should be transmitted to node where the task is allocated on. In that case, a job processing time increases owing to data transmission time. To avoid that case, we schedule tasks into two steps. In the first step, tasks are sorted in the order of high data locality. In the second step, tasks are exchanged to improve their data localities based on a location information of data. In performance evaluation,we compare the proposed method based Hadoop with a default Hadoop on a small Hadoop cluster in term of the job processing time and the number of tasks sorted to node without data to be processed by them. The result shows that the proposed method lowers job processing time by around 18%. Also, we confirm that the number of tasks allocated to node without data to be processed by them decreases by around 25%.

Feature normalization as a pre-processing step has been widely used in classification problems to reduce the effect of different scale in each feature dimension and error as a result. Most of the existing methods, however, assume some distribution function on feature distribution. Even worse,existing methods do not use the labels of data points and, as a result, do not guarantee the optimality of the normalization results in classification. In this paper, proposed is a supervised rank normalization which combines rank normalization and a supervised learning technique. The proposed method does not assume any feature distribution like rank normalization and uses class labels of nearest neighbors in classification to reduce error. SVM, in particular, tries to draw a decision boundary in the middle of class overlapping zone, the reduction of data density in that area helps SVM to find a decision boundary reducing generalized error. All the things mentioned above can be verified through experimental results

In this paper, security mechanism of internal network(CAN) of vehicle is a very incomplete state and the possibility of external threats as a way to build a test environment that you can easily buy from the market by the vehicle's ECU(Electric Control Unit) to verify and obtain a CAN message. Then, by applying it to ECU of the real car to try to attack is proposed. A recent study,Anyone can see plain-text status of the CAN message in the vehicle. so that in order to verify the information is vulnerable to attack from outside, analyze the data in a vehicle has had a successful attack, but attack to reverse engineering in the stationary state and buying a car should attempt has disadvantages that spatial, financial, and time costs occurs. Found through the car's ECU CAN message is applied to a real car for Potential threats outside of the car to perform an experiment to verify and equipped with a wireless network environment, the experimental results,proposed method through in the car to make sure the attack is possible. As a result, reduce the costs incurred in previous studies and in the information absence state of the car, potential of vehicle's ECU attack looks.

Camera performance of smartphone recently has been developed as much as the digital camera. Interest in applications As a result, many people take pictures and the number of people who are interested in application according to photos has been steadily increasing. However, there are only synthesis programs which are arraying some photos, overlapping multiple images. The model proposed in this paper, base on the emotion that is extracted from the facial expressions by combining the background and applying effects filters. And it can be also utilized in various fields more than any other synthesis programs.

In this paper, an effective scheme was proposed to estimate simple convex surface and simple concave surface which exist in image. This scheme is applied to input image to estimate simple convex surface or simple concave surface. When simple convex surface or simple concave surface exists, another proposed efficient interpolation scheme is used for the interpolated pixel to have the characteristics of simple convex surface or simple concave surface. The magnified image using the proposed schemes is more similar to the real image than the magnified image using the previous schemes. The PSNR values of the magnified images using the proposed schemes are greater than those of the magnified images using the previous interpolation schemes.

This paper introduces a touch recognition method for touch screen systems based on the SIFT(Scale Invariant Feature Transform) algorithm for stable touch recognition under strong noises. This method provides strong robustness against the noises and makes it possible to effectively extract the various size of touches due to the SIFT algorithm. In order to verify our algorithm we simulate it on the Matlab with the channel data obtained from a real touch screen. It was found from the simulations that our method could stably recognize the touches without regard to the size and direction of the touches. But, our algorithm implemented on a real touch screen system does not support the realtime feature because the DoG(Difference of Gaussian) of the SIFT algorithm needs too many computations. We solved the problem using the DoM(Difference of Mean) which is a fast approximation method of DoG.

In this paper, we propose a fast video retargeting method which preserves the contents of a video and converts the image size. Since the conventional Seam Carving which is the well-known content-aware image retargeting technique uses the dynamic programming method, the repetitive update procedure of the accumulation energy is absolutely needed to obtain seam. The energy update procedure cannot avoid the processing time delay because of many operations by the image full-searching. By applying the proposed method, frames which have similar features in video are classified into a scene, and the first frame of a scene is resized by the modified Seam Carving where multiple seams are extracted from candidate seams to reduce the repetitive update procedure. After resizing the first frame of a scene, all continuous frames of the same scene are resized with reference to the seam information stored in the previous frame without the calculation of the accumulation energy. Therefore, although the fast processing is possible with reducing complexity and without analyzing all frames of scene, the quality of an image can be analogously maintained with an existing method. The experimental results show that the proposed method can preserve the contents of an image and can be practically applied to retarget the image on real time.

In the RFID system, multiple tags respond in the process of identifying multiple tags in the reader's interrogation zone, resulting in collisions. Tag collision occurs when two or more tags respond to one reader, so that the reader cannot identify any tags. These collisions make it hard for the reader to identify all tags within the interrogation zone and delays the identifying time. In some cases, the reader cannot identify any tags. The reader needs the anti-collision algorithm which can quickly identify all the tags in the interrogation zone. The proposed algorithm efficiently divides tag groups through an efficient separation to respond, preventing collisions. Moreover, the proposed algorithm identifies tags without checking all the bits in the tags. The prediction with efficient separation reduces the number of the requests from the reader.

In Instant message service, the server should process instant messages and request messages which include many presence resources for users. And it also precesses massive notification messages generating from the subscribed presence resources. In this paper a new architecture of instant message service with multiple servers which can distribute loads efficiently as the number of users increases has been suggested. It also provides various functions to users using extended call processing language. The user subscribes presence information and call processing language script which describes user's functions. The server processes instant messages, presence services and call processing language scripts. New extended presence information data structure has been suggested and new call processing language operation tags have been added. Therefore extendability of the system can be increased and various services which combine presence service and call processing can be provided in this system. Furthermore instant message processing module has been integrated in the server to decrease the amount of SIP(Session Initiation Protocol) messages, and it also improves system efficiency, The performance of our proposed system has been analysed by experiments.

Mobile mobility and data reliability should be guaranteed as well as amounts of data services are essential in the era of smart media. In order to improve the reliability of high-speed data,strong channel coding and modulation techniques are required. In this paper, the structure of Turbo TCM decoder, applying high-order modulation techniques and the DPSAM method which improves performances in time-selective fading channels in the case of burst errors are suggested through the optimal decoding method and iteration decoding so as to improve bandwidth efficiency in Turbo Codes with excellent encoding gain. The proposed method in comparison with the existing method is that 3dB is superior in case that BER is 10­­-² and the number of iterations is 3. In addition, the function is improved at approximately 6dB in case that BER is 10­­-³ and the number of iterations is 7. The proposed method requires additional bandwidth; however, the bandwidth loss can be overcome through Turbo TCM technology on the additional bit rate from the bandwidth loss.

In this paper, we suggest a secure data dissemination by Lightweight Individual Encryption Multicast scheme over wireless sensor networks using the individual encryption method with Forward Error Correction instead of the group key encryption method. In wireless sensor networks,a sink node disseminates multicast data to the number of sensor nodes to update the up to date software such as network re-programming and here the group key encryption method is the general approach to provide a secure transmission. This group key encryption approach involves re-key management to provide a strong secure content distribution, however it is complicated to provide group key management services in wireless sensor networks due to limited resources of computing,storage, and communication. Although it is possible to control an individual node, the cost problem about individual encryption comes up and the individual encryption method is difficult to apply in multicast data transmission on wireless sensor networks. Therefore we only use 0.16% of individually encrypted packets to securely transmit data with the unicast to every node and the rest 99.84% non-encrypted encoded packets is transmitted with the multicast for network performance.

In this paper, we proposed SSL VPN-based network access control technology which can verify user authentication and integrity of user terminal. Using this technology, user can carry out a safety test to check security services such as security patch and virus vaccine for user authentication and user terminal, during the VPN-based access to an internal network. Moreover,this system protects a system from external security threats, by detecting malicious codes, based on behavioral patterns from user terminal's window API information, and comparing the similarity of sequential patterns to improve the reliability of detection.

A teacher needs documented information includes basic information about students and lectures to teach students. Currently, both non-electronic and electronic teachers diary are used in most of the field of education. designed and implemented. The electronic teachers diarys only driven on desktop PC. Therefore, managing school affairs with this un-portable system is very inefficient. In this paper, we designed and Implementation Smart Teachers Diary System to check students’information in any time and place with own smart device.

This research is to suggest a method for investigating car number plates among the information managed in parking facilities. The investigation of car number plate is generally used to know how long vehicles are parked. Also, it can provide the information about the parking turnover rate and the mean parking duration of parked vehicles. This research performs the investigation using cameras at a distance of time. That is, the given distance of time from cameras is assigned to each parked vehicle, and then it can find the mean parking time of parked vehicles. Also, it can check the parking turnover rate of parked vehicles at a space unit of parking lot in an hour. The information such as the mean parked duration and the parking turnover rate of parked vehicles taken from this method is helpful to find and understand the inefficient use of parking facilities. With this suggested method, this research attempted to check the mean parking duration and the parking turnover rate of parked vehicles.

The purpose of this study was to analyze the impact of internet addiction by self-esteem level. Most of the existing research has introduced a variety of methods to treat the addiction but the study for casual factors are not entirely satisfactory. Internet addiction is intensified by a variety of casual factors, but during the survey to validate the hypothesis that the biggest impact is the self-esteem level. According to this study, psychological factors of self-esteem is caused an internet addiction than social environmental factor and familial factor. The results of this study can be utilized in a variety of programs to increase the level of self-esteem as a reference for the treatment of internet addiction.

This paper proposes a O(E) polynomial-time algorithm that has been devised to simultaneously solve edge-coloring problem and graph classification problem both of which remain NP-complete. The proposed algorithm selects an edge connecting maximum and minimum degree vertices so as to determine the number of edge coloring χ′(G′). Determined χ′(G′) is in turn either △(G) or △(G)+1. Eventually, the result could be classified as class 1 if  χ′(G′)= △(G) and as category 2 if  χ′(G′)= △(G)+1. This paper also proves Vizing's planar graph conjecture, which states that 'all simple, planar graphs with maximum degree six or seven are of class one, closing the remaining possible case', which has known to be NP-complete.

TIn this paper, we find the face in color images and the ability to track the face was implemented. Face tracking is the work to find face regions in the image using the functions of the computer system and this function is a necessary for the robot. But such as extracting skin color in the image face tracking can not be performed. Because face in image varies according to the condition such as light conditions, facial expressions condition. In this paper, we use the skin color pixel extraction function added lighting compensation function and the entire processing system was implemented, include performing finding the features of eyes, nose, mouth are confirmed as face. Lighting compensation function is a adjusted sine function and although the result is not suitable for human vision, the function showed about 4% improvement. Face features are detected by amplifying, reducing the value and make a comparison between the represented image. The eye and nose position, lips are detected. Face tracking efficiency was good.

In this paper, we proposed that the functionality of teenage school girl cosmetics to improve the performance of the new product development and efficient production of information, analysis and policy analysis system for the SNS. The proposed system functional cosmetics of high school girls on the SNS efficient algorithms to analyze the content and methodology proposed to maximize the throughput of the system, to minimize the execution time of each task. In addition, functional cosmetics of high school girls in the state by identifying the symbols, the analytical results in the development and production of products to reflect propose a visual methodology. Therefore, the proposed system only in cosmetics, as well as an analysis similar to rapidly changing consumer preferences in the manufacturing sector can be applied in various ways

This study first aims to investigate from the users' perspective what service is the most efficient to users and what service is relatively the most effective in contrast to investment among a variety of services provided by smartphone manufacturers, telecommunication companies, and related corporations. In addition, this research suggests implicatively important elements for making the future model of smartphone services. For this end, this study finds out the factors which generate users' positive or negative attitudes towards smartphone use through a questionnaire of those who are using smartphones at present. In particular, by applying Theory of Planned Behavior, this study analyzes the influence exerted by the user's belief towards the kinds of services by setting up Attitudinal Belief, Subjective Norms, and Control Belief which have an influence on attitude from the perspective of smartphone providing detailed services. The results of this study will eventually help the smartphone manufacturers, telecommunication companies, and related corporations to establish smartphone marketing strategy as well as to select the smartphone services which will have popular appeal to their users.

The purpose of this study was to analyze university student's standard of self-efficacy and subjective well-being by the Encouragement Group Counseling Program which would be able to help the students to secure their reaction capability on changing social environment as well as school adaption. Thus, this study investigated how an application of the Encouragement Group Counseling Program affects on unive rsity students' self-efficacy and subjective well-being. As a result, it was revealed that the application of the Encouragement Group Counseling Program has a significant influence on both self-efficacy and subjective well-being. It seemed that people can be positive and have both self-confidence and psychological stability when they are encouraged. Therefore, this study suggested a necessity of the Encouragement Group Counseling Program which supports undergraduate students to have encouragement themselves.

This study divides and traces experience courses of families’ disorganization and reorganization of North Korean refugees in North Korea, China, and South Korea after settlement respectively,from the course of their escaping North Korea to entering South Korea. Through these results, the study is to propose political implications. Main data for the study were analyzed through a case study as a qualitative study method, targeting eight people from July in 2012 to March in 2013. From the study result, though North Korean refugees seemed to disorganize and leave family relations in the course of escaping North Korea, it was found out that this is not disorganization but a preparatory stage which saves families standing at the crossroads of life and death and makes a chance to live with them someday. In these courses, in order for them to overcome their situations and survive, while repeating disorganization and reorganization of families, they used them as a way of saving themselves and their families. It was discovered that these phenomena always occurred simultaneously.

This research paper examined to the influencing factors to adopt national policies of international organization's environment. For this a multivariate regression model has been used to examine cross-national differences in environmental policy adoption. The data analysis was conducted by regression analysis, the indexed point of international environmental agreements were ratified by each nation on the measure of independent variables for a sample of 130 countries in all parts of the world. From analysis results, overall, the regression analysis illustrates that the regression model generally fits our predictions for independent variables. The finding has revealed that external determinants are stronger than internal ones in explaining the level of national environmental policy adoption in relation to international environmental cooperation. Namely, All international environmental organizations, international nongovernmental organizations, and regional multinational institutes proved to function in a positive way in influencing number nations to have a favorable attitude toward international environmental policies. The findings of this study will provide helpful information on how to improve the efficacy of the Korean environmental policy system.

Cybersquatting is a type of conflicts between a trademark and a domain, and refers to “behaviors of registering, retaining, transferring, and using the identical or similar domain name in bad faith for the profit from the mark such as trademark”. That is, it is preoccupying behavior to abuse the fact that the domain name in the Internet can be freely registered on a first come, first served basis and can’t duplicate. Though this should be prohibited, given the reality that most of our daily lives are based in the Internet, this is creating many problems in IT environment beyond social structure in rule of law. Therefore, this study has the purpose that it provides cybersquatting-related information and suggests legislative implications hereafter through the analysis of cybersquatting-related precedent from the Supreme Court.

This study critically review the textbooks and the syllabus of computer network courses currently used at universities, and the specifications of the certifications concerned to provide the students with the competitive and optimized course contents. Considering the vitality of the practicum in the computer network courses, we also suggest a new learning-instruction case study that focuses on the practice by analyzing the computer network practice test simulators which are certified nationally and the internationally. The proposed learning-instruction case study for computer network courses includes the weekly core lessons and contents, study goals and key points, the practice theme, handy tools based on two track of lecture and practice. Therefore it is expected to be a quite resourceful and practical teaching plan for the teacher, and a highly achievement of learning outcomes through motivation which can facilitate CCNA certification enrolling in the field of network aspect for the learner

The purpose of this study is to analyse the effects of social network service on the collaborative learning. Four groups were categorized depending on the use of different types of the social network services – Kakao Talk, Facebook, both Kakao Talk and Facebook, and unused group. A preliminary test revealed that there was no difference in mobile efficacy, career decision making self-efficacy, course interest among the four groups. In the post test, the groups that used either Kakao Talk group or the group that used both Kakao Talk and Facebook retained significantly higher average score in team collaboration scale than Facebook group and unused group. The analysis of the messages in Facebook exhibited that the group used both Kakao Talk and Facebook generated larger number of messages, read, replies, clicks of “good” than the groups used only Facebook. These results strongly support the statistical significance.

This research was conducted to analyze parents’ attitudes on the issues related to the Smart Education Initiative Korea. The questions included the usefulness of major digital tools for educational purposes, knowledge on the Smart Education, necessity for better educational methods, and Bring Your Own Devices (BYOD) policy. A total of 432 response cases from the parents were analyzed considering the parents’ age, academic level, and income. As a result parents regarded desktop PCs as more effective tools for learning when compared to tablet PCs. Meanwhile, mobile devices and SNSs were hardly considered as instructional tools. Second,familarity and understanding of the Smart Education were proportional to household income and mothers’ education levels. Third, parents needed for the change in educational methods and agreed with the importance of students’ self-regulated learning, collaboration, inquiry ability and creativity. Fourth, regarding BYOD, parents were willing to buy devices with a reasonable price. In conclusion, it is required to reflect the results of the study when implementing the Smart Education throughout the nation.