• International Journal of Reliability and Applications
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• v.2 no.3
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• pp.147-160
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• 2001

The reliability of computer software is of prime importance for all developers of software. The complicated nature of detecting and removing faults from software has led to a plethora of models for reliability growth. One of the most basic of these is the Jelinski Moranda model, where it is assumed that there are N faults in the software, and that in testing, bugs (or faults) are encountered (and removed when defected) according to a stochastic process at a rate which at a given point in time is proportional to the number of bugs remaining in the system. In this research, we consider the possibility that imperfect repair may occur in any attempt to remove a detected bug in the Jelinski Moranda model. We let p represent the probability that a fault which is discovered or detected is actually perfectly repaired. The possibility that the probability p may differ before and after release of the software is also considered. The distribution of both the number of bugs detected and perfectly repaired in a given time period is studied. Cost models for the development and release of software are investigated, and the impact of the parameter p on the optimal release time minimizing expected costs is assessed.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.1
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• pp.111-115
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• 2008

We present a simple and effective method to reduce loop-related false alarms raised by buffer-overrun static program analyzer. Interval domain buffer-overrun analyzer raise many false alarms in analyzing programs that frequently use loops and arrays. Firstly, we classified patterns of loop-related false alarms for loop-intensive programs, such as embedded programs or mathematical libraries. After that we designed a simple and effective false alarm refiner, specialized for the loop-related false alarms we classified. After the normal analysis of program in which alarms considered as false. We implemented this method on our buffer-overrun analyzer with the result that our refinement method decreased the number of false alarms by 32% of total amount the analyzer reported.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.9
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• pp.3885-3906
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• 2020

Hybrid fuzzing which combines fuzzing and concolic execution, has proved its ability to achieve higher code coverage and therefore find more bugs. However, current hybrid fuzzers usually suffer from inefficiency and poor scalability when applied to complex, real-world program testing. We observed that the performance bottleneck is the inefficient cooperation between the fuzzer and concolic executor and the slow symbolic emulation. In this paper, we propose a novel solution named EPfuzzer to improve hybrid fuzzing. EPfuzzer implements two key ideas: 1) only the hardest-to-reach branch will be prioritized for concolic execution to avoid generating uninteresting inputs; and 2) only input bytes relevant to the target branch to be flipped will be symbolized to reduce the overhead of the symbolic emulation. With these optimizations, EPfuzzer can be efficiently targeted to the hardest-to-reach branch. We evaluated EPfuzzer with three sets of programs: five real-world applications and two popular benchmarks (LAVA-M and the Google Fuzzer Test Suite). The evaluation results showed that EPfuzzer was much more efficient and scalable than the state-of-the-art concolic execution engine (QSYM). EPfuzzer was able to find more bugs and achieve better code coverage. In addition, we discovered seven previously unknown security bugs in five real-world programs and reported them to the vendors.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1449-1453
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• 2008

Galla Rhois is a nest of parasitic bug, has been traditionally used for the treatment of the therapy of diarrhea, peptic ulcer, hemauria, etc., that showed various anti-inflammatory activity, and other biological properties. We studied the effect of Galla Rhois ethanol extract. we investigated whether compounds isolated from the ethanol extract of Galla Rhois, could modulate iNOS and COX-2 expression in RAW 264.7 macrophages stimulated with lipopolysaccharide (LPS). We found compounds that suppressed LPS-induced iNOS and COX-2 expression. Suppression of the expression of iNOS and COX-2 was in parallel with the comparable inhibition of the production of nitric oxide (NO) and prostaglandin E2 (PGE2). Our results suggest that compounds can inhibit NO and PGE2 productions through suppression of LPS-induced iNOS and COX-2 expression. Because COX-2- or iNOS-dependent mechanisms are involved in inflammation and tumor progression, our findings provide a new uncovering mechanism responsible for anti-inflammatory and antitumor effects of Galla Rhois.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.90-93
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• 2003

The function, which represents the closed curve, is found from the sampling data by S-System in this study. Two methods are proposed. One is the extension of S-System. The data x and y are regarded as input data, and the data z=0 as output data. To avoid the trap into the invalid function, the judgment points (x$\_$j/, y/sug j/) are introduced. They are arranged in the inside and the outside of the closed curve. By introducing this concept, the functions representing closed curve are found by S-System. This method is simple because of a little extension of S-System. It is, however, difficult for the method to find the complex function like a hand-written curve. Then another method is also proposed. It uses the system incorporating the argument function. The closed curve can be expressed by the argument function. The relatively complex function, which represents the closed curve like a hand-written curve, is found by utilizing argument function.

• Journal of the Korea Computer Industry Society
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• v.4 no.10
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• pp.559-570
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• 2003

Automation of programming-error detection is an important part of intelligent programming language tutoring systems. In this paper, a new programming error detection approach for novice programmers is proposed by plan matching and program execution. Program execution result is used to resolve the restricted programming plan representation and to provide a confirming evidence for the plan matching differences. By checking the values of shared variable between the related plans, we can detect the cause-effect relationship between the plans. With this relationship and the test data, we can explain the program's unexpected behaviors according to the bug's cause and resulting effects.

• The Microorganisms and Industry
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• v.25 no.2
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• pp.11-18
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• 1999

The sweet potatoes infected with witches'-broom disease were collected in the growing fields in Jeon-bug area, Korea. As a possible control plant, Ipomoea batatas L.var. Suwon 147 was selected. The pathogen was identified by various methods ; such as mechanical transmission, antibiotic reactions and electron microscopy. In the results attained the author believed the pathogen of the sweet potato infected with witches' broom to be a mycoplasma-like organism. the results are as follows : 1. Mycoplasma-like bodies were occurred in the phloem region of the sweet potatoes infected with witches'-broom and its particles were sized in the range of about 200-2,500m.mu.. The membrane of the pathogen was observed to be made of an unit. 2. Responsibilities to the antibiotices were sensitive in case of tetracycline and terramycin, and root dipping method showed remarkable than foliage spray. 3. The infection was developed by the grafting transmission but by the insects, Myzus persicae and Cicadella viridis. 4. rosette, witches'-broom, stunt, yellowish, mosaic and necrosis were observed as the symptomps of the disease.

• Journal of the Korean Professional Engineers Association
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• v.5 no.17
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• pp.3-10
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• 1972

This report is the result of the basic geologic investigation for the purpose of preparing the long-term development program of the U-jeon Consolidated Coal kline. The Consolidated Coal Mine is located at Gujeol-ri, Wangsan-myeon, Myeongju-gun, and Yucheon-ri, Bug-myeon, Jeongseon-gun, Gan-gweon Province (128$^{\circ}$ 43′10.4"-128$^{\circ}$ 46′10. 4"of east long-ititude, 37$^{\circ}$ 30′-37$^{\circ}$ 33′ of north latitude). This region, the western part of Taebaek mountain range, shows a ragged mountinous feature. Formations of the Pyeongan System of Paleozoic Era are distribu ted in the region with the surrounding Great Limestone Series of Joseon System which covers the south-eastern part of the region. The Pyeongan System is divided into four formations, namely, the Hongjeom, the Sadong, the Gobang and the Hongam, in ascending order. The sadong Formation intercalates several coal beds, and two coal beds out of them are minable. The coal beds are variable in thickness, having the repeated swelled or poket and the pinched parts, which suggest all intense disturbance caused by folding. The heat value of the coal is 5, 500cal. on the average. The total amount of coal reserves of the U-jeon consolidated Coal Mine is estimated at about thirty million metric tons.

• Korean journal of applied entomology
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• v.56 no.1
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• pp.87-92
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• 2017

The Samurai wasp, Trissolcus japonicus (Ashmead) (Hymenoptera: Platygasteridae) is recognized as a solitary parasitoid on eggs of the stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), an economic pest causing severe damage to fruits, in South Korea. The wasp appears to be a potential biological agent of the pest. In addition, T. itoi Ryu and T. nigripedius (Nakagawa) were found to parasitize eggs of Eurydema gebleri Kolenati and Dolycoris baccarum Linnaeus, respectively. Diagnostic characters and photographs are provided for identification, and host records of Korean Trissolcus species are also given.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.281-282
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• 2019

We have developed a composition containing three kinds of plant extracts (Deris, Citronella, and Cinnamon) and supplements (xanthan gum and silicone-based compounds) having high control effects on Metcalfa pruinosa. This composition had more than 90% of the nymph bug control effect in the ginseng plantation. In addition, since the insecticidal rate is high for other absorptive pests, it is considered that it can be used as a countermeasure against the implementation of the PLS (positive list system).