• Journal of the Korean Geosynthetics Society
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• v.19 no.4
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• pp.11-20
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• 2020

This study introduced the compact grouting method that can be used for improving soft ground and restoring buildings with unequal subsidence. The pump used in the traditional compact grouting method is a system that injects one hole each, which reduces the construction efficiency, and the analog injection method manually manages the construction by field workers, making it difficult to manage consistent quality. Pump and quality control system were developed to solve problems in existing construction. Since field supervisor determines amount of injected materials by using analog equipment and controls manually, it is difficult to manage consistent quality of construction. Therefore, the quality control system was developed in order to solve that problem. The quality control system consists of automatic mixing system of injection materials, multiple simultaneous injection pumps, and injection management monitoring system. Performance of the quality control system was verified through on-site testing, and ground improvement performance was verified through quality testing after testing and testing of the compact grouting method. Therefore, it is expected that the integrated quality control system developed will improve the quality assurance and efficiency and stability of construction at sites where construction and quality verification are difficult.

• The Transactions of the Korea Information Processing Society
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• v.4 no.7
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• pp.1821-1841
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• 1997

This paper presents an automated protocol conformance test sequence generation based on formal methods for LOTOS specification by using and applying many existing related algorithms and technique, such as the testing framework, Rural Chinese Postman tour concepts. We use the state-transition graphs obtained from LOTOS specifications by means of the CAESAR tool. This tool compiles a specification written in LOTOS into an extended Petri net, from which a transition graph of a event finite-state machine(EvFSM) including data is generated. A new characterizing sequence(CS), called Unique Event sequence(UE sequence) is defined. An UE sequence for a state is a sequence of accepted gate events that is unique for this state. Some experiences about UE sequence, partial UE sequence and signature are also explained. These sequences are combined with the concept of the Rural Chinese Postman Tour to obtain an optimal test sequence which is a minimum cost tour of the reference transition graph of the EvFSM. This paper also presents a fault coverage estimation experience of an automated method for optimized test sequences generation and the translation of the test sequence obtained by using our tool to TTCN notation are also given. A prototype of the proposed framework has been built with special attention to real application in order to generated the executable test cases in an automatic way. This formal method on conformance testing can be applied to the protocols related to IN, PCS and ATM for the purpose of verifying the correctness of implementation with respect to the given specification.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.2
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• pp.165-170
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• 2014

Shear horizontal (SH) waves propagate as a type of plate wave in a thin sheet. The dispersion characteristics of SH waves can be used for signal analysis. Therefore, SH-waves are useful for monitoring the structural health of a thin-sheet-structure. An electromagnetic acoustic transducer (EMAT), which is a non-contact ultrasonic transducer, can generate SH-waves easily by varying the shape and array of magnets and coils. Therefore, an EMAT can be applied to an automated ultrasonic testing system for structural health monitoring. When used as a sensor, however, the EMAT has a weakness in that electromagnetic interference (EMI) noise can occur easily in the automated system because of motors and electric devices. Alternatively, a fiber optic sensor works well in the same environment with EMI noise because it uses a light signal instead of an electric signal. In this paper, a fiber Fabry-P$\acute{e}$rot interferometer (FFPI) was proposed as a sensor to receive the SH-waves generated by an EMAT. A simple test was performed to verify the performance of the FFPI sensor. It is thus shown that the FFPI can receive SH-wave signals clearly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.11
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• pp.4460-4467
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• 2010

Recent advances in computer technology have brought more dependence on software to railway systems and changed to computer systems. Hence, the reliability and safety assurance of the vital software running on the embedded railway system is going to tend toward very critical task. Accordingly, various software test and validation activities are highly recommended in the international standards related railway software. In this paper, we presented an automated analysis tool and standard for software testing coverage in railway system, and presented its result of implementation. We developed the control flow analysis tool estimating test coverage as an important quantitative item for software safety verification in railway software. Also, we proposed judgement standards due to railway S/W Safety Integrity Level(SWSIL) based on analysis of standards in any other field for utilizing developed tool widely at real railway industrial sites. This tool has more advantage of effective measuring various test coverages than other countries, so we can expect railway S/W development and testing technology of real railway industrial sites in Korea.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.3_4
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• pp.186-193
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• 2003

In recent years the complexity of digital systems has increased dramatically. Although semiconductor manufacturers try to ensure that their products are reliable, it is almost impossible not to have faults somewhere in a system at any given time. As complexity of circuits increases, the necessity of more efficient organized and automated methods for test generation is growing. But, up to now, most of popular and extensive methods for test generation nay be those which sequentially produce an output for an input pattern. They inevitably require a lot of time to search each fault in a system. In this paper, corresponding test patterns are generated through the partitioning method among those based on the exhaustive method. In addition, the method, which can discovers faults faster than other ones that have been proposed ever by inserting a pattern in parallel, is designed and implemented.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.6
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• pp.1561-1567
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• 1990

Recently, some reports of experimental research on the distribution of fatigue crack propagation rate have been published, and the reliability evaluation using the results of research for the mechanical structure has been executed. Since the thicknesses of specimens used in the published reports are limited to the thin ones, the applicability of the results into the mechanical structure with another thickness seems to be doubtful. That is, not only the quantitative evaluation, but also qualitative evaluation of the effect of specimen thickness has not been executed. In this study, an experimental investigation has been done by using the new type automated multi-stage fatigue testing machine which was developed by the author. The influence of specimen thickness for the distribution of fatigue crack propagation rate with the results is discussed.

• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.3
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• pp.261-266
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• 2002

Up to now a wide variety of researches on inpipe robots for inspection have been introduced, but it still seems to be difficult to construct a robot providing mobility sufficient to navigate inside the complicated configuration of underground pipelines. The robot for the inspection of pipelines should freely move along the basic configuration of pipelines such as along horizontal or vertical pipelines. Moreover it should be able to travel along reducers and elbows, and especially the capability for steering in branches is essential to it. In this report, citical points and technologies in the development of the inpipe inspection robots are introduced and inpipe robots developed for last several years are introduced.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1822-1830
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• 2002

The microsatellites are the short tandem repeats of 1 to 6 bp long monomer sequences that are repeated several times. These short tandem repeats are considered to be generated by the slipped strand mispairing. Based on the unique capability of alternating purine-pyrimidine residues to form Z-DNA, the possible role of the microsatellites in gene regulation has been proposed. The microsatellites are highly polymorphic, follow Mendelian inheritance and are evenly distributed throughout the genomes of eukaryotes. They are easy to isolate and the polymerase chain reaction based typing of the alleles can be readily automated. These properties make them the preferred markers for comparison of the genetic structure of the closely related breeds/populations; very high-resolution genetic mapping and parentage testing etc. The microsatellites have rapidly replaced the restriction fragment length polymorphism (RFLP) and the random amplified polymorphic DNA (RAPD) in most applications in the population genetics studies in most species, including the various farm animals viz. cattle, buffalo, goat, sheep and pigs etc. More and more reports are now available describing the use of microsatellites in pigs ranging from measurement of genetic variation between breeds/populations, developing high resolution genetic maps to identifying and mapping genes of biological and economic importance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.8
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• pp.1989-2009
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• 2013

How to discover router vulnerabilities effectively and automatically is a critical problem to ensure network and information security. Previous research on router security is mostly about the technology of exploiting known flaws of routers. Fuzzing is a famous automated vulnerability finding technology; however, traditional Fuzzing tools are designed for testing network applications or other software. These tools are not or partly not suitable for testing routers. This paper designs a framework of discovering router protocol vulnerabilities, and proposes a mathematical model Two-stage Fuzzing Test Cases Generator(TFTCG) that improves previous methods to generate test cases. We have developed a tool called RPFuzzer based on TFTCG. RPFuzzer monitors routers by sending normal packets, keeping watch on CPU utilization and checking system logs, which can detect DoS, router reboot and so on. RPFuzzer' debugger based on modified Dynamips, which can record register values when an exception occurs. Finally, we experiment on the SNMP protocol, find 8 vulnerabilities, of which there are five unreleased vulnerabilities. The experiment has proved the effectiveness of RPFuzzer.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.10
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• pp.3750-3770
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• 2021

This study investigates open-source dynamic XSS filters used as security devices in web applications to account for the effectiveness of filters in protecting against XSS attacks. The experiment involves twelve representative filters, which are examined individually by placing them into the final output function of a custom-built single-input-form web application. To assess the effectiveness of the filters in their tasks of sanitizing XSS payloads and in preserving benign payloads, a black-box testing method is applied using an automated XSS testing framework. The result in working with malicious and benign payloads shows an important trade-off in the filters' tasks. Because the filters that only check for dangerous or safe elements, they seem to neglect to validate their values. As some safe values are mistreated as dangerous elements, their benign payload function is lost in the way. For the filters to be more effective, it is suggested that they should be able to validate the respective values of malicious and benign payloads; thus, minimizing the trade-off. This particular assessment of XSS filters provides important insight regarding the filters that can be used to mitigate threats, including the possible configurations to improve them in handling both malicious and benign payloads.