• The KIPS Transactions:PartA
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• v.12A no.5 s.95
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• pp.365-374
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• 2005

Schedulability analysis is necessary to build reliable embedded real-time systems. For schedulability analysis, worst-case execution time(WCET) analysis that computes upper bounds of the execution times of tasks, is required indispensably. WCET analysis is done in two phases. The first phase is high-level analysis that analyzes control flow and finds longest paths of the program. The second phase is low-level analysis that computes execution cycles of basic blocks taking into account the hardware architecture. In this thesis, we design and implement integrated WCET analysis tools. We develop the WCET analysis tools for XScale-based system called WATER(WCET Analysis Tool for Embedded Real-time system). WATER consist of high-level flow analyzer and low-level execution time analyzer. Also, We compare real measurement for execution of program with analysis result calculated by WATER.

• Journal of Internet Computing and Services
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• v.17 no.4
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• pp.51-60
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• 2016

Embedded software has requirements such as real-time and environment independency. The real-time requirement is affected from worst-case execution time of loaded tasks. Therefore, to guarantee real-time requirement, we need to determine a program's worst-case execution time using static analysis approach. However, the existing methods for worst-case execution time analysis do not consider the environment independency. Thus, in this paper, in order to provide environment independency, we propose a method for measuring task's execution time from the source codes. The proposed method measures the execution time through the control flow graph created from the source codes instead of the executable codes. However, the control flow graph created from the source code does not have information about execution time. Therefore, in order to provide this information, the proposed method identifies the relationships between statements in the source code and instructions in the executable code. By parameterizing those parts that are dependent on processors based on the relationships, it is possible to enhance the flexibility of the tool that measures the worst-case execution time.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.7
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• pp.510-514
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• 2009

If the existing real-time systems are integrated based on SOA, real-time SOA should be developed. Generally, in real-time SOA a service can be divided into several small services and their estimated execution time is given by provider systems. However, an estimation, which analyzes time elements related to transmit and receive messages among requesters and providers, is needed. In order to enhance QoS of Web service, this paper proposes enhanced worst-case execution time estimation by considering WS-transaction and common use of multi-processors system.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.6
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• pp.1365-1376
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• 1997

In this paper, we designed real time mechanism control language and proposed execution time analysis technique. It was impossible to handle real-time mechanism control programs like programmable controller, numerical controller, distributed control system and robot controller with general purpose programming languages and operating systems because they have to process electric signals generated by thousands of sensors at the same at the same time and in real time. So we made it possible to predict plausibility of time constraint constructs of tiem constraint construct of a real time application program at compilation time by adding time constraint constructs and mechanism synchronization structure to conditional statement and iteration statement of a programming language and developing execution time analysis technique.

• International Journal of Computer Science & Network Security
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• v.23 no.7
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• pp.49-60
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• 2023

The amount of data generated by electronic systems through e-commerce, social networks, and data computation has risen. However, the security of data has always been a challenge. The problem is not with the quantity of data but how to secure the data by ensuring its confidentiality and privacy. Though there are several research on cloud data security, this study proposes a security scheme with the lowest execution time. The approach employs a non-linear time complexity to achieve data confidentiality and privacy. A symmetric algorithm dubbed the Non-Deterministic Cryptographic Scheme (NCS) is proposed to address the increased execution time of existing cryptographic schemes. NCS has linear time complexity with a low and unpredicted trend of execution times. It achieves confidentiality and privacy of data on the cloud by converting the plaintext into Ciphertext with a small number of iterations thereby decreasing the execution time but with high security. The algorithm is based on Good Prime Numbers, Linear Congruential Generator (LGC), Sliding Window Algorithm (SWA), and XOR gate. For the implementation in C, thirty different execution times were performed and their average was taken. A comparative analysis of the NCS was performed against AES, DES, and RSA algorithms based on key sizes of 128kb, 256kb, and 512kb using the dataset from Kaggle. The results showed the proposed NCS execution times were lower in comparison to AES, which had better execution time than DES with RSA having the longest. Contrary, to existing knowledge that execution time is relative to data size, the results obtained from the experiment indicated otherwise for the proposed NCS algorithm. With data sizes of 128kb, 256kb, and 512kb, the execution times in milliseconds were 38, 711, and 378 respectively. This validates the NCS as a Non-Deterministic Cryptographic Algorithm. The study findings hence are in support of the argument that data size does not determine the execution.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.4
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• pp.11-20
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• 1998

Fault simulatior has been used to compute exact fault coverages of test vectors for digial circuits. But it is time consuming because execution time is proportional to square of circuit size. Recently, several algorithms for testability analysis have been published to cope with these problems. COP is very fast and accurate but cannot be used for sequential circuits, while STAFAN can be used for sequential circuits but needs vast amount of execution time due to good circuit simulation. We proposed EXTASEC which gave fast and accurate fault coverage. But it shows noticeable errors for a few sequential circuits. In this paper, it is shown that the inaccuracy is due to uninitializble flipflops, and we propose ITEM to improve the EXTASEC algorithm. ITEM is an improved evaluation method of fault coverage by analysis of backward lines and uninitializable flipflops. It is expected to perform efficiently for very large circuits where execution time is critical.

• Journal of Information Processing Systems
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• v.7 no.4
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• pp.707-716
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• 2011

It is important that desktop grids should be able to aggressively deal with the dynamic properties that arise from the volatility and heterogeneity of resources. Therefore, it is required that task scheduling be able to positively consider the execution behavior that is characterized by an individual resource. In this paper, we implement a log analysis system with REST web services, which can analyze the execution behavior by utilizing the actual log data of desktop grid systems. To verify the log analysis system, we conducted simulations and showed that the resource group-based task scheduling, based on the analysis of the execution behavior, offers a faster turnaround time than the existing one even if few resources are used.

• Journal of the Korea Society of Computer and Information
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• v.15 no.4
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• pp.37-45
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• 2010

A system which needs timely accuracy has to design and to verify correctly about execution-time for reliability. Accordingly, it is necessary for timing analysis tools, and much previous research worked. In timing analysis tool, there are two methods. One is a static analysis, and the other is a measurement based analysis. A static analysis is able to spend time less than a measurement based analysis method, but has low reliability of analysis result caused by hard to estimate time of I/O caused by various hardware. A measurement based analysis can be close analysis to real result, but it is hard to adapt to actual application, and spend a lot of time to get result of analysis. As such, this paper present a software monitoring architecture to supply reliability of static analysis process. In a presented architecture, it can select target as needed measurement through static analysis, and reuse result of measurement exist. Therefore, The architecture can reduce overload of time and performance for measurement, and improve the reliability which is the worst problem of static analysis.

• Journal of The Korean Association of Information Education
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• v.23 no.1
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• pp.19-27
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• 2019

This study analyzed the effect of an unplugged educational program which focuses on the algorithm execution time analysis on enhancing the computational thinking of the third grade students. An unplugged educational program was developed by following the procedures of the ADDIE model based on the result of the demand analysis conducted with 70 incumbent elementary school teachers and 120 third grade students. The developed program was applied to 24 third grade students for 36 classes in six days and a comparison was made through pre-post comparison tests with 24 students who were taught with a board game program for the same period of time. As a result, the unplugged education program which focuses on the algorithm execution time analysis is deemed to have positive effect on the computational thinking of the third grade students.

• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.69-72
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• 1999

In this paper, the implementation method for the extending real-time execution in MMS Implementation is proposed. For this, the method of MMS over ATM(Asynchronous Transfer Mode) and IEEE 802.12 network is analyzed. By the analysis of service response time, making the ASIC of encoding and decoding parts are proposed for one of the real time extension in MMS. The main goals of this paper to analyze and propose suitable methods to meet the real time requirements in MMS applied system.