• Journal of Convergence Society for SMB
• /
• v.5 no.3
• /
• pp.21-26
• /
• 2015

As mobile contents grow up, In App Billing is brisk at applications including mobile contents. But some of users don't pay and use charged content for free to use cheating payment module or hacking through applications. Call this bypass payment. Applications, helping bypass, are Freedom, IAP Cracker, and DNS server suggested by the hacker named Borodin. In case of mobile game, Despite sell a lot of charged content but income is different revenue in sales log with real profits. Because of users using bypass payment application. Management plan to bypass payment are checking OrderID, encrypting public key and verifying receipt.

• Journal of Korean Society for Quality Management
• /
• v.42 no.4
• /
• pp.747-756
• /
• 2014

Purpose: The purpose of this study is to apply the Bayesian estimation methodology for producing 'Korean Standard -Quality Excellence Index' model and prove the effectiveness of the new approach based on survey data by comparing the current index with the new index produced by Bayesian estimation method. Methods: The 'Korean Standard -Quality Excellence Index' was produced through the collected survey data by Bayesian estimation method and comparing the deviation with two results for confirming the effectiveness of suggested application. Results: The statistical analysis result shows that suggested estimator, that is, empirical Bayes estimator improves the effectiveness of the index with regard to reduce the error under specific loss function, which is suggested for checking the goodness of fit. Conclusion: Considering the Bayesian techniques such as empirical Bayes estimator for producing the quality excellence index reduces the error for estimating the parameter of interest and furthermore various Bayesian perspective approaches seems to be meaningful for producing the corresponding index.

• ETRI Journal
• /
• v.18 no.4
• /
• pp.265-286
• /
• 1997

This paper presents a new software development environment that supports an integrated methodology for covering all phases of software development and gives integrated methods with tools for ITUT (Telecommunication Standardization Section of the International Telecommunication Union) languages. The design of the environment to improve software productivity and quality is based on five main concepts: 1) formal specifications based on SDL (Specification and Description Language) and MSC (Message Sequence Charts) in the design phase, 2) verification and validation of those designs by tools, 3) automatic code generation and a safe separate compilation scheme based on CHILL (CCITT High-Level Language) to facilitate programming-in-the-many and programming-in-the-large. 4) debugging of distributed real-time concurrent CHILL programs, and 5) simulation of application software for integrated testing on the host machine based on CHILL. The application results of the environment compared with other approaches show that the productivity is increased by 19 % because of decreasing implementation and testing cost, and the quality is increased by 83 % because of the formal specifications with its static and dynamic checking facilities.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2004.10a
• /
• pp.292-297
• /
• 2004

The conventional computerized numerical controller (CNC) of machine tools has been increasingly replaced by a PC-based open architecture CNC (OAC) which is independent of the CNC vendor. The OAC and machine tools with OAC led the convenient environment where it is possible to implement user-defined application programs efficiently within CNC. Tis paper proposes a method of operational fault cause diagnosis which is based on the status of programmable logic controller (PLC) in machine tools with OAC. The operational fault is defined as a disability state occurring during normal operation of machine tools. The faults are occupied by over 70% of all faults and are also unpredictable as most of them occur without any warning. Two diagnosis models, the switching function (SF) and the step switching function (SSF), are propose in order to diagnose the fault cause quickly and exactly. The cause of an occurring fault is logically diagnosed through a fault diagnosis system (FDS) using the diagnosis models. A suitable interface environment between CNC and develope application modules is constructed in order to implement the diagnostic functions in the CNC domain. The diagnosed results were displayed on a CNC monitor for machine operators and provided to a remote site through a web browser. The result of his research could be a model of the fault cause diagnosis and the remote monitoring for machine tools with OAC.

• Proceedings of the Korean Information Science Society Conference
• /
• 2007.10d
• /
• pp.462-466
• /
• 2007

본 논문에서는 데이터 방송 환경에서의 DSM-CC 관련 Object Carousel Manager를 구현하고, 성능향상을 위한 캐싱 기법을 제안한다. Object Carousel Manger 구현은 다음과 같은 순서로 이루어진다. 먼저, 방송스트림에서 해당 PID별로 얻어온 모듈을 캐시에 저장한 후, 모듈에서 BIOP 메세지 오브젝트별로 분석한 뒤 파싱 한다. 그런 후, 파싱된 BIOP 메시지 오브젝트를 해당 서비스 게이트웨이, 디렉터리. 파일로 변환해준다. 마지막으로, 변환된 파일시스템에서 해당하는 Xlet Application을 실행시켜 주게 된다. 시스템성능 향상을 위해서 제안하는 캐싱 기법은 다음과 같다. DII의 Caching Priority Descriptor를 이용하여, Object들을 포함하고 있는 각각의 모듈에 대해서 Version Number를 Checking하는 주기인 Transparency_level을 부여하고, Application 실행 시 보여 주는 화면 순서대로 필요한 모듈에 대해 우선순위를 부여하여, 캐시에 업데이트 시 이를 반영하여, 시스템 전체의 성능을 향상시킨다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.2
• /
• pp.486-503
• /
• 2023

Logs play an important role in mastering the health of the system, experienced operation and maintenance engineer can judge which part of the system has a problem by checking the logs. In recent years, many system architectures have changed from single application to distributed application, which leads to a very huge number of logs in the system and manually check the logs to find system errors impractically. To solve the above problems, we propose a method based on Message Middleware and ATT-GRU (Attention Gate Recurrent Unit) to detect the logs anomaly of distributed systems. The works of this paper mainly include two aspects: (1) We design a high-performance distributed logs collection architecture to complete the logs collection of the distributed system. (2)We improve the existing GRU by introducing the attention mechanism to weight the key parts of the logs sequence, which can improve the training efficiency and recognition accuracy of the model to a certain extent. The results of experiments show that our method has better superiority and reliability.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.31 no.2
• /
• pp.25-37
• /
• 2023

The purpose of this study is to develop and technically implement the design and scenario of cabin safety contents for virtual reality (VR)-based cabin safety learning for aviation service majors. The process for developing VR cabin safety learning contents consisted of a total of four stages: learning stage, research stage, verification stage, and application stage. The cabin safety scenario items for the production of VR learning contents reflected the occurrence of an emergency, the procedure for survival from impact, and the evacuation procedure from the aircraft as the core. For the technical implementation of learning contents, modeling work is conducted by checking scenario reviews, types and numbers of objects related to equipment and facilities, and items of interaction. In addition, the connection work with the actual metaverse platform is carried out to enable the utilization of the manufactured facilities and equipment objects. Finally, application tests were carried out to reconfirm supplementary items.

• International Journal of Computer Science & Network Security
• /
• v.24 no.1
• /
• pp.1-8
• /
• 2024

In contemporary education, the rapid advancement of digital technologies elevates demands for integrating the latest tools into the learning process. Mathematical analysis, as a discipline, benefits from computer mathematics in distance education, enhancing practical aspects and enabling individualized learning. This article addresses the integration of the Maple computer mathematics system into higher education, specifically in teaching "Mathematical Analysis." Emphasizing its role in distance learning, computer mathematics optimizes the educational environment, reducing the time required for knowledge acquisition. The article showcases the application of Maple in finding extremum points and introduces an educational software simulator, enabling students to practice the method. The simulator, developed within Maple, facilitates self-checking and enhances the study of functions. Conclusions drawn from the study highlight the positive impact of these tools on distance education, affirming Maple's role in enhancing professional training and information culture among higher education students.

• Journal of Korea Multimedia Society
• /
• v.8 no.7
• /
• pp.974-987
• /
• 2005

As the ad hoc networks have been received a great deal of attention to not only the military but also the industry applications, some security mechanisms are required for implementing a practical ad hoc application. In this paper, we propose a security architecture in ad hoc networks for the purpose of supporting ID-based public key cryptosystems because of the advantage that ID-based schemes require less complex infrastructure compared with the traditional public key cryptosystems. We assume a trusted key generation center which only issues a private key derived from IDs of every nodes in the system setup phase, and use NIL(Node ID List) and NRL(Node Revocation List) in order to distribute the information about IDs used as public keys in our system. Furthermore, we propose a collaborative status checking mechanism that is performed by nodes themselves not by a central server in ad-hoc network to check the validity of the IDs.

• Journal of KIISE:Software and Applications
• /
• v.29 no.12
• /
• pp.860-872
• /
• 2002

Fault tree analysis is the most widely used saftly analysis technique in industry. However, the analysis is often applied manually, and there is no systematic and automated approach available to validate the analysis result. In this paper, we demonstrate that a real-time model checker UPPAAL is useful in formally specifying the required behavior of safety-critical software and to validate the accuracy of manually constructed fault trees. Functional requirements for emergency shutdown software for a nuclear power plant, named Wolsung SDS2, are used as an example. Fault trees were initially developed by a group of graduate students who possess detailed knowledge of Wolsung SDS2 and are familiar with safety analysis techniques including fault tree analysis. Functional requirements were manually translated in timed automata format accepted by UPPAAL, and the model checking was applied using property specifications to evaluate the correctness of the fault trees. Our application demonstrated that UPPAAL was able to detect subtle flaws or ambiguities present in fault trees. Therefore, we conclude that the proposed approach is useful in augmenting fault tree analysis.