• The Transactions of the Korea Information Processing Society
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• v.1 no.4
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• pp.438-451
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• 1994

A low complexity, fault detecting computer architecture for utilisation in programmable logic controllers is designed. The cyclic operating mode of PLCs and a specification level, graphical programming paradigm based on the interconnection of application oriented standard software function modules are architecturally supported. Thus, by design, there is no semantic gap between the programming and machine execution levels enabling the safety licensing of application software by an extremely simple, but rigorous method, viz, diverse back translation.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.3
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• pp.145-154
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• 2007

Dynamic update of kernel can change kernel functionality and fix bugs in runtime. Dynamic update is important because it leverages availability, reliability and flexibility of kernel. An instruction-granularity update technique has been used for dynamic update. However, it is difficult to apply update technique for a commodity operating system kernel because development and maintenance of update code must be performed with assembly language. To overcome this difficulty, we design the function-granularity dynamic update system which uses high-level language such as C language. The proposed update system makes the development and execution of update convenient by providing the development environment for update code which is same for kernel development. We implement this system for Linux and demonstrate an example of update for do_coredump() function which is reported it has a vulnerable point for security. The update was successfully executed.

• The KIPS Transactions:PartD
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• v.14D no.1 s.111
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• pp.97-106
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• 2007

In this paper, the business process was easily modeled by distinguishing between the business process and work logic. Based on this model, B2Bi collaboration Workflow modeling tool, which facilitates collaboration, was designed and implemented. The collaboration workflow modeling tool consists of 3 components; business process modeling tool, execution engine and monitoring tool. First, a business process modeling tool is used to build a process map that reflects the business logic of an application in a quick and accurate manner. Second an execution engine provides a real-time execution environment for business process instance. Third, a monitoring tool provides a real-time monitoring function for the business process that is in operation at the time. In addition to this, it supports flexibility and expandability based on XML and J2EE for the linkage with the legacy system that was used previously, and suggests a solution for a new corporate strategy and operation.

• The KIPS Transactions:PartC
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• v.9C no.4
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• pp.453-458
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• 2002

Recently, the number of hacking, that use buffer overflow vulnerabilities, are increasing. Although the buffer overflow Problem has been known for a long time, for the following reasons, it continuos to present a serious security threat. There are three defense method of buffer overflow attack. First, allow overwrite but do not allow unauthorized change of control flow. Second, do not allow overwriting at all. Third, allow change of control flow, but prevents execution of injected code. This paper is for allowing overwrites but do not allow unauthorized change of control flow which is the solution of extending compiler. The previous defense method has two defects. First, a program company with overhead because it do much thing before than applying for the method In execution of process. Second, each time function returns, it store return address in reserved memory created by compiler. This cause waste of memory too much. The new proposed method is to extend compiler, by processing after compiling and linking time. To complement these defects, we can reduce things to do in execution time. By processing additional steps after compile/linking time and before execution time. We can reduce overhead.

• The KIPS Transactions:PartD
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• v.17D no.2
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• pp.147-156
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• 2010

Conformance testing for embedded software is to check whether software was correctly implemented according to software specification or not. In conformance testing, test scenarios must be extracted to cover every test cases of software. In a general way, test scenarios simply focus on testing all functions at least one time. But, test scenarios are necessary to consider efficiency of test execution. In this paper, we propose a test scenario extraction method by considering function's execution time and waiting time for user interaction. A test model is a graph model which is generated from state machine diagram and test cases in software specification. The test model is augmented by describing test execution time and user interaction information. Based on the test model, test scenarios are extracted by a modified Dijkstra's algorithm. Our test scenario approach can reduce testing time and improve test automation.

• Archives of design research
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• v.15 no.3
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• pp.115-126
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• 2002

The occupational execution technique and the ability of people has been changed along with the change of thinking and the development of complicated social structure. The needs of learner's self-controlled learning system is arise to increase the occupational execution technique and adaptation in such a changing social environment. To meet these needs, we must develop systematic approach on the module-type educational material system. The purpose of this study lies on developing the module-type educational material system and its application in aspects of occupational execution ability. Based on the job analysis of advertising design, 1 analyze the learning ability for the occupational execution and abstract knowledge, function, attitude from each learning category of each learning ability. All these processes are the basis of developing the module-type educational material system. and the system will be appreciated in many other fields not only on advertising design.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.4
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• pp.919-928
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• 2018

Out-Of-Bounds (OOB) is one of the most powerful vulnerabilities in heap memory. The OOB vulnerability allows an attacker to exploit unauthorized access to confidential information by tricking the length of the array and reading or writing memory of that length. In this paper, we propose a method to automatically detect OOB vulnerabilities in heap memory using dynamic symbol execution and shadow memory table. First, a shadow memory table is constructed by hooking heap memory allocation and release function. Then, when a memory access occurs, it is judged whether OOB can occur by referencing the shadow memory, and a test case for causing a crash is automatically generated if there is a possibility of occurrence. Using the proposed method, if a weak block search is successful, it is possible to generate a test case that induces an OOB. In addition, unlike traditional dynamic symbol execution, exploitation of vulnerabilities is possible without setting clear target points.

• Journal of Korea Multimedia Society
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• v.10 no.9
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• pp.1197-1208
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• 2007

These days, most of SMART card, JAVA card, picked up the JAVA Card Platform gets the position as a standard. Java Card technology provides implantation, platform portability and high security function to SMART Card. Compared to normal Smart Card, JAVA card has a defect that is a low running speed caused by a distinctive feature of JAVA programming language. Factors that affect JAVA Card execution speed are the method how to save the data and install the applets of JAVA Card installation instrument. In this paper, I will offer the plan to improve JAVA Card program's loading and execution speed. At Java Card program, writing, updating and deleting process for data at EEPROM can be improved of Java Card speed by using high speed RAM. For this, at JAVA Card as a application of RAM, I will present prefetching LRU-ORL Buffer Cache Technique that is suitable for Java Card environment. As a data character, managing all data created from JAVA Curd at Buffer Cache, decrease times of recording at maximum for EEPROM so that JAVA Card program upload and execution speed will be improved.

• Korean Journal of Childcare and Education
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• v.15 no.1
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• pp.37-55
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• 2019

Objective: This study investigated whether executive function has a significant relationship to concrete, picture, and language clue tasks of the arithmetic story problem-solving ability, and its effects. Methods: The participants in the study were 112 young children at childcare centers. The following methods were used to evaluate executive function: Day-Night/Flag-Raising tasks, DCCS tasks, and digit span-reverse digit span methods. To measure the arithmetic story problem-solving ability concrete, picture, and language clue tasks were evaluated. Results: First, the higher the child's age, the higher their executive function and arithmetic story problem-solving abilities were. Second, there is a significant positive correlation between a young child's executive function and arithmetic story problem-solving ability. Third, when the task presentation method varied for concrete, picture, and language clue tasks, the effect of the subordinate factor of the execution function of the arithmetic story problem-solving ability also varied. Conclusion/Implications: Analysis confirmed the relationship between young children's executive function and arithmetic story problem-solving ability. The results are meaningful in showing that the sub-factors of the executive function have different influences on concrete, picture, and language clue tasks of the arithmetic story problem-solving ability.

• The KIPS Transactions:PartA
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• v.11A no.4
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• pp.243-250
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• 2004

Monitoring is used to see if a real-time system provides a service on time. Generally, monitoring for real-time focuses on investigating the current status of a real-time system. To support a stable performance of a real-time system, it should have not only a function to see the current status of real-time process but also a function to predict executions of real-time processes, however. The legacy prediction model has some limitation to apply it to a real-time monitoring. First, it performs a static prediction after a real-time process finished. Second, it needs a statistical pre-analysis before a prediction. Third, transition probability and data about clustering is not based on the current data. We propose the execution prediction model based on learning algorithm to solve these problems and apply it to real-time monitoring. This model gets rid of unnecessary pre-processing and supports a precise prediction based on current data. In addition, this supports multi-level prediction by a trend analysis of past execution data. Most of all, We designed the model to support dynamic prediction which is performed within a real-time process' execution. The results from some experiments show that the judgment accuracy is greater than 80% if the size of a training set is set to over 10, and, in the case of the multi-level prediction, that the prediction difference of the multi-level prediction is minimized if the number of execution is bigger than the size of a training set. The execution prediction model proposed in this model has some limitation that the model used the most simplest learning algorithm and that it didn't consider the multi-regional space model managing CPU, memory and I/O data. The execution prediction model based on a learning algorithm proposed in this paper is used in some areas related to real-time monitoring and control.