• Journal of KIISE:Software and Applications
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• v.34 no.7
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• pp.616-624
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• 2007

Sudoku can be regarded as a SAT problem. Various encodings are known for encoding Sudoku as a Conjunctive Normal Form (CNF) formula, which is the standard input for most SAT solvers. Using these encodings for large Sudoku, however, generates too many clauses, which impede the performance of state-of-the-art SAT solvers. This paper presents an optimized CNF encodings of Sudoku to deal with large instances of the puzzle. We use fixed cells in Sudoku to remove redundant clauses during the encoding phase. This results in reducing the number of clauses and a significant speedup in the SAT solving time.

• The KIPS Transactions:PartD
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• v.16D no.3
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• pp.371-380
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• 2009

Recently, lots of research on automated test data generation has been actively done. However, techniques for automated test data generation presented so far have been proved ineffective for programs with flag variables. It can present problems when considering embedded systems such as engine controllers that make extensive use of flag variables to record state information concerning devices. This paper introduces a technique for generating test data effectively for programs with flag variables. The presented technique transforms the test data generation problem into a SAT(SATisfiability) problem and makes advantage of SAT solvers for automated test data generation(ATDG). For the ends, we transform a program under test into Alloy which is the first-order relational logic and then produce test data via Alloy analyzer.

• The KIPS Transactions:PartD
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• v.15D no.6
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• pp.777-784
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• 2008

Recently in the field of model checking, to overcome the state explosion problem, the method of using a SAT-solver is mainly researched. To use a SAT-solver, the system to be verified is translated into CNF and the Boolean cardinality constraint is widely used in translating the system into CNF. In BCC it is dealt with set of boolean variables, but there is no translating method of the sequence among Boolean variables. In this paper, we propose methods for translating the problem, which is extracting a subsequence with length k from a sequence of Boolean variables, into CNF formulas. Through experimental results, we show that our method is more efficient than using only BCC.

• Journal of KIISE:Software and Applications
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• v.35 no.11
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• pp.661-670
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• 2008

In some applications of software engineering such as the verification of software model or embedded program, SAT solver is used. To practical use a SAT solver, a problem is encoded to a CNF formula, but because the formula has lower expressiveness than software models or source codes, optimal CNF encoding is required. In this paper, we propose optimal encoding techniques for the problem of "Selecting adjacent $k{\leq}n$ among n objects," Through experimental results we show the proposed constraint is efficient and correct to solve Japanese puzzle. As we know, this paper is the first study about CNF encoding for adjacency in BCC.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.320-324
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• 1995

Solubilization of microsomal ${\Delta}^{5}-3{\beta}$-hydroxy steroid acyl transfearse(${\Delta}^{5}-3{\beta}$-OH-SAT) of rat brain and its reconstitution into liposomes were investigated. Among the detergents utilized for the solubilization, deoxycholic acid was superior to Tween 80 or Triton X-100 for the reconstituted activity of ${\Delta}^{5}-3{\beta}$-OH-SAT. The enzyme activity was shown to be affected by the nature of phospholipids used for the preparation of the liposome. Phosphatidylcholines from egg yolk and soybean showed the highest activity of ${\Delta}^{5}-3{\beta}$-OH-SAT and phosphatidylethanolamine came next. However phosphatidylserine and phosphatidic acid showed a lower activity than those obtained before the reconstitution. This study suggests that the presence of quaternary ammonium salt or amine group in the phospholipids stimulates the activity of ${\Delta}^{5}-3{\beta}$-OH-SAT. However the presence of a carboxylic group or the absence of the amine group may have an inhibitory effect on the ${\Delta}^{5}-3{\beta}$-OH SAT.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.378-381
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• 2008

최근 정형 검증 분야에서 만족가능성 처리기를 사용한 연구가 많아지면서 이를 적용한 사례들이 많이 나타나고 있다. 만족가능성 처리기를 사용하기 위해서는 검증 되어야 할 시스템을 CNF식으로 변환해야 한다. 우리는 루빅 큐브를 만족가능성 처리기를 통해 풀어보기 위해 이를 CNF식으로 변환해 보았다. 루빅 큐브는 정육면체로 이루어진 퍼즐의 일종으로 모든 면이 각각 한가지 색으로만 채워져야 하는 문제이다. 우리는 본 논문에서 만족가능성 처리기를 사용한 사례 중에 아직 적용한적이 없는 루빅 큐브를 CNF식으로 변환해 풀었음을 보여준다.

• Journal of Life Science
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• v.20 no.7
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• pp.1012-1018
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• 2010

The aim of this study was to determine whether Alzheimer's amyloid precursor protein (APP) is dysregulated in adipose tissues of C57BL/6 male mice by high-fat diet (HFD) induced obesity, aging, or streptozotocin (STZ)-induced diabetes. APP mRNA expression was examined by quantitative real-time PCR (QPCR) in subcutaneous (SAT) and epididymal adipose tissues (EAT) from mice in 8 different condition groups. By combining conditions of age (16 weeks/26 weeks of age), diet (normal diet (ND)/high-fat diet), and induction of diabetes (non-diabetic/diabetic), 88 mice were divided into 8 different groups. QPCR demonstrated that APP expression in SAT was significantly increased by about two-fold in HFD-induced obese mice compared to both 16 week-old and 26 week-old mice in the ND group (16 weeks p=0.001; 26 weeks p<0.0001), but no changes in EAT was found. Particular effects of aging on APP gene expression were not observed in either adipose tissue depots. Significantly decreased APP expression was found in SAT in STZ-induced diabetic mice fed on ND or HFD at 16 weeks of age (ND p<0.05; HFD p<0.01). Linear regression analysis demonstrated that APP expression levels correlated with body weight in both the non-diabetic group (R=0.657, p<0.0001, n=39) and the diabetic group (R=0.508, p=<0.0001, n=49), but did not correlate with plasma glucose levels, which suggests that decreased APP expression in STZ-induced diabetic mice is most likely due to weight loss rather than hyperglycemia. These data confirm APP dysregulation by weight changes in humans and suggest a possible role linking midlife obesity with the later development of amyloidogenesis in the brain of older patients with Alzheimer's disease.

• Sleep Medicine and Psychophysiology
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• v.14 no.1
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• pp.33-41
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• 2007

Objectives: It has been known that the contents of dreams change according to neuro-developmental differences in sex, progression of age and various environments, unlike the established psychoanalytic theory. To investigate the changes, we collected "most recent dream report" and analyzed the contents of dreams by using Hall/Van de Castle System. Method: Most recent dream reports were gathered from age 12-14 years old, 2,673 middle school students (1,544 male 1,129 female) and analyzed those reports using Hall/Van de Castle System. The data were sorted in SAS and dream SAT. Result: There were prominent differences between male and female middle school students in Male/Female Percentage (male/ female；56%/35%), Familiarity Percentage (57%/69%), Aggression/Friendliness Percentage (79%/65%), Befriender Percentage (50%/33%), Physical Aggression Percentage (90%/70%), Indoor Setting Percentage (40%/55%), Negative Emotion Percentage (56%/68%) and Torso/Anatomy Percentage (51%/36%). There were significant differences in Male/Female Percentage (65%/44%), Friendliness, Physical Aggression and Self Negativity Percentage in male and there were significant differences in Friendliness, Familiarity and Friends Percent in female between 1st and 2nd grade. But, it showed much similar dream patterns between 2nd and 3rd grade in both gender. In male, Aggression/Character Index with male character is significantly increased by 2nd grade (1st/ 2nd/ 3rd；0.48/ 1.04/0.98), In female, Friendliness/Character Index with male character had significantly decreased by 2nd grade (0.38/ 0.19/0.20). Conclusion: There were apparent differences between age 12-14 years old male and female. Male adolescents have differences mostly in categories related with aggression, but female adolescents have differences in categories related with environment or character. It shows that developmental level of male are slower than female as of yet and male needs more active interpersonal relationship to find identity. Otherwise, the influences of passive attitude and actual circumferential environment are reflected in female's dream. There are no prominent differences among ages, but age 12-13 years old adolescents shows significant differences in interacting with the other gender. It means that circumferential environment and interpersonal relationship affect the contents of dreams and also the cognitive development related to age and sex. Afterwards, the development of dreams could be better understood through the neurocognitive study and dream analysis between other ages and nations.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.11
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• pp.24-35
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• 2012

In this paper, we propose a dynamic lane control scheme with a traffic predictor module and a rate controller for reconciling with commercial optical PHY modules in energy efficient optical Ethernet systems. The commercial high speed optical Ethernet system capable of 40/100Gbps employs 4 or 10 multiple optical transceivers over WDM or multiple optical links. Each of the transceivers is always turned on even if the link is idle. To save energy, we propose the dynamic lane control scheme. It allows that several links may be entirely turned off in a low traffic load and frames are handled on the remaining active links. To preserve the byte order even if the number of active links may be changed, we propose a rate controller to be sat on the reconciliation sublayer. The main role of the controller is to insert null byte streams into the xGMII of inactive lanes. For the PHY module, the null input streams corresponding to inactive lanes will be disregarded on inactive PMDs. It is very handy to implement the rate controller module with MAC in FPGA without any modification of commercial PHYs. It is very crucial to determine the number of active links based on the fluctuated traffic load, we provide a simple traffic predictor based on both the current transmission buffer size and the past one with different weighting factors for adapting to the traffic load fluctuation. Using the OMNET++ simulation framework, we provide several performance results in terms of the energy consumption.

• Research in Plant Disease
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• v.28 no.2
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• pp.82-91
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• 2022

Recently, several in vitro studies have reported antiviral activity of agents of systemic acquired resistance against plant virus infection, but the approach has not been applied in a wide range of agricultural fields. The objective of this study was to evaluate the inhibitory effect of the exogenous application of salicylic acid (SA), chitosan (CH), or eugenol (EG) in tomato yellow leaf curl virus (TYLCV) infection of greenhouse-grown tomato plants. In vitro, the initial time of symptom was observed in TYLCV-infected plants (VP) of the resistant cultivar 'Superdotaerang' at 12 days post inoculation (dpi) after application of antiviral agents. At 32 dpi, the disease rate of TYLCV in the CHT+VP (0.1% chitosan and virus infected control) treated plants was 87.5%, lower than that of the other treatment. However, the virus content in the CHT+VP treated plants was higher than those of the other treatments, and SA, EG, and CH did not show significant effect on plant height or shoot and root fresh weight. Our results from summer-cultivated greenhouse-grown tomatoes show that none of the tested agents had an inhibitory activity on viral infection or yield of tomato 'Dotaerangsola'cultivar. In contrast, all treated 'TY Giants' cultivars that possessed TYLCV resistance genes Ty-1 and Ty-3a did not show typical symptoms and the virus content was remarkably lower than those in the TYLCV treated plants in 'Superdotaerang'. The results of this research indicated that the planting of resistant tomato cultivars was effective method instead of using SA, EG, and CH (known as resistance-inducing factors for control) of TYLCV in the field.