Recently, Bitcoin which is digital currency and cryptocurrency is getting worldwide attention since Bitcoin has an ability to replace legal tender unlike other existing cyber currency. Especially, most Bitcoin trading is done between two traders such as P2P method and it does not require a third-party to make sure reliability and it records every transaction details, so it is more transparent then traditional financial trade, so the number of users is increasing. However, Bitcoin, which has been recognized for transparency, confidentiality and stability among traders has recently been threatened by illegal transactions such as money laundering and the attack on the exchange. These threats to Bitcoin are becoming social problems. At first, it seems that most of the digital currency is difficult to get hacked due to the Blockchain technology. However, threats such as digital money leaks by user account hacking and paralyzing the servers are increasing. In this paper, it will examine the features of the Bitcoin and the threatening elements to secure marketability of digital currency such as Bitcoin and receive more interest from public in domestic. The paper will examine the problems of Blockchain technology on speculative transactions and fraudulent behavior by analyzing the problems of Bitcoin transaction. Lastly, it will propose ways to make transparent and secure digital currency transactions.

The aerial support air sculptures currently exhibited in indoor spaces are similar to simple ad balloons, using multiple rope strands. Users now want more advanced unfixed sculptures, and hope these will develop into buoyant sculptures that can maintain the attitudes that users want on their own. This study investigated an attitude control system for unfixed levitation sculptures that can levitate with no rope and continuously maintain a certain attitude at a height specified by the user. To facilitate levitation, the exterior part of the sculpture was made of lightweight fibers, and the interior part was filled with helium gas. The controller was composed of a microprocessor of the dsPIC30F line from microchip, gyro, acceleration, and earth magnetic field sensors, and a highly efficient brushless DC (BLDC) electric motor. The attitude and position control system requires scheduling considering the trajectories of the sculpture and the control system, because the roles of the overall components are more important than those of a single controller. Furthermore, the system was designed like a fusion system that is expanded and controlled as a total controller, because it is interconnected with various sensors. The attitude control system of buoyant sculptures was implemented in this study, such that it can actively cope with the position, direction, stopping, and time aspects. The system performance was then evaluated.

Nowadays, networked computer systems play an increasingly important role in our society and its economy. They have become the targets of a wide array of malicious attacks that invariably turn into actual intrusions. This is the reason computer security has become an essential concern for network administrators. Recently, a number of Detection/Prevention System schemes have been proposed based on various technologies. However, the techniques, which have been applied in many systems, are useful only for the existing patterns of intrusion. Therefore, probe detection has become a major security protection technology to detection potential attacks. Probe detection needs to take into account a variety of factors ant the relationship between the various factors to reduce false negative & positive error. It is necessary to develop new technology of probe detection that can find new pattern of probe. In this paper, we propose an hybrid probe detection using Fuzzy Cognitive Map(FCM) and Self Adaptive Module(SAM) in dynamic environment such as Cloud and IoT. Also, in order to verify the proposed method, experiments about measuring detection rate in dynamic environments and possibility of countermeasure against intrusion were performed. From experimental results, decrease of false detection and the possibilities of countermeasures against intrusions were confirmed.

In this paper presents the MPPT tracking algorithm using angle control of flexible PV in BIPV. The proposed algorithm is based on MPPT tracking algorithm for curtain wall using flexible PV. It is an algorithm to find optimal power generation condition by controlling the angle of flexible PV using the air layer of window. The angle of flexible PV tests the power generation by separating the center of flexible PV into the interior angle in the interior direction and the external angle in the center of flexible PV. When the angle of flexible PV was used as interior angle, the generation amount was increased by 15.79% and increased by 8.45% compared with the external angle. MPPT tracking is performed on the generation amount of the interior angle which has the most power after comparing the generation amount according to the bending shape of the flexible PV. This algorithm can be the most efficient method for the curtain wall using flexible PV because the bending pattern with the greatest amount of power generation may be different because the environment of the building applying the curtain wall is different.

This paper presents hardware implementation of background timing-skew calibration technique for time-interleaved analog-to-digital converters (TI ADCs). The timing skew between any two adjacent analog-digital (A/D) channels is detected by using pure digital Finite Impulse Response (FIR) delay filter. This paper includes hardware architecture of the system, main units and small sub-blocks along with control logic circuits. Moreover, timing diagrams of logic simulations using ModelSim are provided and discussed for further understanding about simulations. Simulation process in MATLAB and Verilog is also included and provided with basic settings need to be done. For hardware implementation it not practical to work with all samples. Hence, the simulation is conducted on 512 TI ADC output samples which are stored in the buffer simultaneously and the correction arithmetic is done on those samples according to the time skew algorithm. Through the simulated results, we verified the implemented hardware is working well.

MANET consists of only wireless nodes having limited processing capability. It processes routing and data transmission through cooperation among each other. And it is exposed to many attack threats due to the dynamic topology by movement of nodes and multi-hop communication. Therefore, the reliability of transmitted data between nodes must be improved and security of integrity must be high. In this paper, we propose a method to increase the reliability of transmitted data by providing a secure cryptography protocol. The proposed method used a hierarchical structure to provide smooth cryptographic services. The cluster authentication node issues the cluster authentication key pair and unique key to the nodes. The nodes performs the encryption through two steps of encryption using cluster public key and block encryption using unique key. Because of this, the robustness against data forgery attacks was heightened. The superior performance of the proposed method can be confirmed through comparative experiment with the existing security routing method.

Korean Identification card or driver license is usually used to verify one's identity in Korea. These are also used as an adult certification. Since the form of these ID card is an analog and it needs to be checked with naked eyes, it might be used maliciously. Someone who's got someone else's ID card can do other things. Therefore, it must be reported rapidly when ID card is lost or stolen. The most serious problem might be occurred when they do not recognize and report the loss. They might suffer from pecuniary or mental damage such as opening a mobile phone service, providing loan or credit card, opening a personal checking account, etc. Thus, this study suggests and compares the ways of avoiding these problems. First, the most effective way is to send the authorization code via mobile phones in consideration of build-up period and cost. The person in charge of business processing department using ID card sends the authorization code via registered mobile phone. The owners submits it to the person and their identifications are confirmed. Next effective way is that the person in charge of business processing department using ID card sends text messages via registered mobile phone. Lastly, the most ineffective way is to introduce and implement the electronic ID card ultimately even though it is expensive and takes a long time to build up the system.

The fifth generation(5G) of wireless networks will connect not only smart phone but also unimaginable things. Therefore, 5G cellular network is facing the soaring traffic demand of numerous user devices. To solve this problem, a huge amount of 5G base stations will need to be installed. The base station positioning problem is an NP-hard problem that does not know how long it will take to solve the problem. Because, it can not find an answer other than to check the number of all cases. In this paper, to solve the NP hard problem, we compare the tabu search and the genetic algorithm using real maps for optimal cell planning. We also perform Monte Carlo simulations to study the performance of the Tabu search and Genetic algorithm for 5G cell planning. As a results, Tabu search required 2.95 times less computation time than Genetic algorithm and showed accuracy difference of 2dBm.

This paper estimate a desired signal in a correlation wireless communication. The transmitted signal is mixed with the information signal, interference, and noise in wireless channel, and it is incident on the receiver. In this paper, we apply MUSIC algorithm and sub-array method to recover the total rank of the correlation matrix in order to estimation a desired signal among receiving signals. Through simulation, we analyze to compare the proposed method with the classical MUSIC algorithm. As a result of the simulation, the proposed method improved the resolution about 10degrees compared to the conventional MUSIC algorithm. We prove the superiority of the proposed method for the desired signal estimation in correlation channel.

It is the approach of development of teaching methods for competency development in business class. This study distinguishes areas that can be commonly applied to many business subjects. And we derive core competencies from the basic skills of NCS. The results of this study are as follows. First, we have established an opportunity to distinguish the subject field of business administration(personnel/organization/strategy, production/operation management, marketing, financial/finance/insurance, accounting, MIS). Second, we have proposed guidelines for the setting of the each subject goals and the setting of the professor's competency. Third, we have summarized teaching method which are studied as valid in business class(lecture method, problem based learning method, action learning teaching method, and management simulation teaching method) and we suggested how to apply teaching methods to the each subject.

Considered as the "new normal" mode of learning, BL has become popular in recent years especially in University education. BL is defined as a learning approach that combines e-learning and face-to-face classroom learning. BL allows for more interactive and reflective learning environment resulting in enhancing learner-directed learning. The adoption of BL in university has made it significant to probe the crucial determinants that would entice instructors and learners to use BL and enhance learning satisfaction. The primary purpose of this study is to investigate the affecting factors of the satisfaction of BL in universities in terms of leaner's aspects. Learner's role is very important in BL, because learner should self-directed study for effective performance and satisfaction in BL environment. Based on prior studies motivation, self-efficacy, and educational expectancy were identified as affecting factors of satisfaction in BL. According to the result of multiple regression, all factors(motivation, self-efficacy, and educational expectancy) were found to be significantly related to the learner's satisfaction in BL. It can provide practical guideline on effective operation strategy for BL in universities.

There is no absolute leadership through East and West. Just as past and present conditions are not the same, it is not easy for past leadership to apply to the present. The best leadership will be the leadership that can represent and lead the changing situation. In that sense, the creative leadership is the most appropriate leadership required by the present age. In the society, research on creative leadership is actively conducted in schools and companies, but there is no research on creative leadership in the military. This is the first study in the military about creative leadership. It is meaningful to understand the understanding of creative leadership and the applicability of the military and to provide a basis for future research. First, we measured the organizational effectiveness of creative leadership. The data were analyzed by factor analysis, correlation analysis, and regression analysis using SPSS 18.0. The results of this study were as follows. First, the organizational effectiveness of creative leadership and organizational goals and achievement were measured, and it was found that there was significant influence on the relationship between creative leadership and organizational effectiveness. I could confirm some. This would be meaningful in that it suggested the possibility of applying the leadership of the creative leadership to lead the change of society and to implement the military command.

This study aims to investigate the effect of personality traits (Big5) of local government officials on job exhaustion. First, we examine the correlation between personal characteristics of individual employees and self-efficacy and the correlation between factors of civil servants' personality characteristics and job stress. Also, it was confirmed whether self-efficacy had a significant effect on job exhaustion and whether job stress had a significant effect on job exhaustion. In order to empirically study this research model, we held a survey based on the employees of Gangnam-gu, Seoul. The main results of this study are as follows : First, it was confirmed that sincerity among personality characteristics affects positive self-efficacy and neuroticism affects negative self-efficacy. However, it was confirmed that extroversion, affinity, and openness were not correlated with self-efficacy. Second, neuroticism has a positive influence on job stress and openness has a negative effect on job stress. However, there was no correlation between extroversion, affinity, sincerity and job stress. Third, the relationship between self-efficacy and job exhaustion turned out to give a negative effect. Finally, job stress was positively influenced by job exhaustion. Therefore, it is necessary to apply the study on personality characteristics (Big5), job stress, and job exhaustion, which have been studied based on service industries, to local government officials. The purpose of this study is to suggest job training for enhancing personality traits that can help reduce the job burden of local government officials.

This study is to discover and substantiate the casual relation between Learning Organization and Organizational Citizenship Behavior, with Supervisor Trust used as moderating variable. Learning Organization and Organization Citizenship Behavior are used, respectively, as independent and dependent variable, Supervisor Trust as moderating variable. The data for this study was collected from 340 public officials who participated in the training program. Data collection tools were used to collect structured questionnaire questionnaires, and dissemination and retrieval of questionnaires were carried out over 6 weeks from February 6 to March 10, 2017. Of the questionnaire distributed, the questionnaire was finally recovered from the questionnaire, with a recall rate of 91.8 %, showing a very high rate of recall. The result showed that Learning Organization is a significant factor for Organization Citizenship Behavior and also that Supervisor Trust plays a role in the control of the relationship between Learning Organization and Organization Citizenship Behavior; thus, in order for Public Organizations to achieve advanced competitiveness, vitalizations of Learning Organization is important.

The objective of this paper is to investigate the effect of character traits of employees of consulting firm on job satisfaction through self-leadership and self-efficacy. The proposed model is based on big5 model of Coasta and McCrae(1992). To validate the proposed model, structural equation model is analyzed with the valid 140 questionnaires collected from Seoul and nearby cities by using Smart PLS 3.0. The results are as follows. First, extraversion has a positive effect on self-leadership, not on self-efficacy. Second, agreeableness has a positive effect on self-leadership, not on self-efficacy. Third, conscientiousness has a positive effect on both self-leadership and self-efficacy. Fourth, emotional stability does not have a positive effect on both self-leadership and self-efficacy. Fifth, openness to experience has a positive effect on both self-leadership and self-efficacy. Sixth, self-leadership has a positive effect on self-efficacy. Seventh, self-leadership has a positive effect on job satisfaction. Last, self-efficacy has a positive effect on job satisfaction. This research proves that, while the character of employees generally forms the meaningful relationship with self-leadership and self-efficacy, in some entries of Big 5 character elements it has still produced the different results with the previous researches, which betrays that the relationship between one's character and self-leadership and self-efficacy can differ according to the characteristic of jobs. It requires further study to prove how each of Big 5 elements differently effects on self-leadership and self-efficacy according to diverse characteristic of jobs.