• Bulletin of the Korean Chemical Society
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• v.19 no.12
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• pp.1351-1355
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• 1998

A simple apparatus for adding a modifying solvent to supercritical CO2 extractant was described. Small, fixed volumes (typically 100 μL) of liquid modifying solvents were delivered during the extraction process by use of an in-line high pressure loop injector and an air pump. Without disconnecting the extraction cell from the supercritical fluid extraction system, the modifying solvent was repeatedly delivered. The solvent modification device was optimized during the extraction of carbaryl and bis(acetylacetonato) copper(Ⅱ). Extraction recoveries from spiked filter paper and soil samples ranged between 22% and 109%, depending on the analyte and matrix components. The addition of polar modifying solvents were necessary to improve the extractability of the nonpolar CO2.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.2
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• pp.44-50
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• 2007

This paper deals with the problem of scheduling jobs and rate-modifying activities on parallel machines. A rate-modifying activity is an activity that changes the production rate of equipment such as maintenance and readjustment. If a job is scheduled after the rate-modifying activity, then the processing time varies depending on the modifying rate of the activity. In this study, we extend the single machine problem to parallel machines problem and propose algorithms is to schedule the rate-modifying activities and jobs to minimize the makespan on parallel machines which is NP-hard. We propose a branch and bound algorithm with three lower bounds to solve medium size problems optimally. Also we develop three heuristics, Modified Longest Processing Time, Modified MULTIFIT and Modified COMBINE algorithms to solve large size problems. The test results show that branch and bound algorithm finds the optimal solution in a reasonable time for medium size problems (up to 15 jobs and 5 machines). For large size problem, Modified COMBINE and Modified MULTIFIT algorithms outperform Modified LPT algorithm in terms of solution quality.

• Journal of the Korea Concrete Institute
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• v.11 no.6
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• pp.69-78
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• 1999

Hydroxyethyl cellulose -based-viscosity modifying admixture and melamine-basd-superplasticizer were selected to be admixtures for self-compacting concrete based on the test results of fluidity and air content of mortar using 3 different viscosity modifying admixtures. The experimental results show that the initial and final set of self-compacting concrete and fly ash concrete with viscosity modifying admixture only have been delayed approximately 5 hours and 8~9 hours, respectively. It is found that the optimum dosage of viscosity modifying admixtures, coarse aggregate and cement content are 0.2% of water content, under 742 kg/$\textrm{m}^3$ and over 364 kg/$\textrm{m}^3$, respectively. Test results also show that the optimum fly ash in replacement of cement is 10% of cement weight for the enhancement of fluidity and long-term strength.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.3
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• pp.177-184
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• 2000

The purpose of this study is to evaluate the performance of a new viscosity modifying admixture for concrete agent. For this purpose, selected test variables were the ratio of water to cement, the ratio of cement to fine aggregate, contents of superplasticizer, contents of viscosity modifying admixture. As a result of this study, it has been found that addition of viscosity modifying admixture to mortar modfies its fluidity and reduces its segregation by increasing the mortar viscosity. And it has been found that a new viscosity modifying admixture do not significantly affect the setting time, air content of mortar.

• Education of Primary School Mathematics
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• v.2 no.2
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• pp.133-144
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• 1998

We examined two kinds of problem posing, 'problem making' and 'problem modifying' to find which one is more effective for improving mathematical problem solving ability according to the student's learning-levels and sexes. The results showed that 'problem making' is more effective for high and middle-level groups than 'problem modifying'. There was no big difference according to the sexes. These facts implies that making a problem when a situation was presented is more effective to develop problem solving ability than modifying a problem ： modifying some conditions and contents of given problem.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.126-131
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• 2005

Richadella dulcifica, a native shrub in tropical West Africa, gives red berries that have the unusual property of modifying a sour taste into a sweet taste. The red berries contain a taste-modifying protein named miraculin. A synthetic gene encoding miraculin was placed under the control of constitutive promoters and transferred to lettuce. High expression of miraculin was obtained, with accumulation of up to 1% total soluble protein in lettuce leaf. In addition, the miraculin expressed in lettuce possesses a taste-modifying activity.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.32 no.2
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• pp.171-179
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• 2022

Self-Modifying-Code is a code that changes the code by itself during execution time. This technique is particularly abused by malicious code to bypass static analysis. Therefor, in order to effectively detect such malicious codes, it is important to identify self-modifying-codes. In the meantime, Self-modify-codes have been analyzed using dynamic analysis methods, but this is time-consuming and costly. If static analysis can detect self-modifying-code it will be of great help to malicious code analysis. In this paper, we propose a static analysis method to detect self-modified code for binary executable programs converted to LLVM IR and apply this method by making a self-modifying-code benchmark. As a result of the experiment in this paper, the designed static analysis method was effective for the standardized LLVM IR program that was compiled and converted to the benchmark program. However, there was a limitation in that it was difficult to detect the self-modifying-code for the unstructured LLVM IR program in which the binary was lifted and transformed. To overcome this, we need an effective way to lift the binary code.

• Journal of Plant Biotechnology
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• v.43 no.4
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• pp.397-404
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• 2016

Sweet and taste modifying proteins are natural alternatives to synthetic sweeteners and flavor enhancers, and have been used for centuries in different countries. Use of these proteins is limited due to less stability and availability. However, recent advances in biotechnology have enhanced their availability. These include production of sweet and taste modifying proteins in transgenic organisms, and protein engineering to improve their stability. Their increased availability in the food, beverage or medicinal industries as sweeteners and flavor enhancers will reduce the dependence on artificial alternatives. Production of transgenic plants using sweet and taste modifying genes, is an interesting alternative to the extraction of these products from natural source. In this review paper, we briefly describe various sweet and taste modifying proteins (such as thaumatin, monellin, brazzein, curculin and miraculin), their properties, and their application for plant development using biotechnological approaches.

• Journal of the Korea Society of Computer and Information
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• v.23 no.8
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• pp.85-93
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• 2018

In this research, it is proposed that a method to hide data by modifying directory index entry information. It consists of two methods: a directory list hiding and a file contents hiding. The directory list hiding method is to avoid the list of files from appearing in the file explorer window or the command prompt window. By modifying the file names of several index entries to make them duplicated, if the duplicated files are deleted, then the only the original file is deleted, but the modified files are retained in the MFT entry intact. So, the fact that these files are hidden is not exposed. The file contents hiding is to allocate data to be hidden on an empty index record page that is not used. If many files are made in the directory, several 4KB index records are allocated. NTFS leaves the empty index records unchanged after deleting the files. By modifying the run-list of the index record with the cluster number of the file-to-hide, the contents of the file-to-hide are hidden in the index record. By applying the proposed method to the case of hiding two files, the file lists are not exposed in the file explorer and the command prompt window, and the contents of the file-to-hide are hidden in the empty index record. It is proved that the proposed method has effectiveness and validity.

• Korean Management Science Review
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• v.30 no.1
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• pp.15-24
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• 2013

We consider the single machine scheduling problem with a rate-modifying activity and time-dependent deterioration after the activity. The class of scheduling problems with rate-modifying activities and the class of scheduling problems with time-dependent processing times have been studied independently. However, the integration of these classes is motivated by human operators of tasks who has fatigue while carrying out the operation of a series of tasks. This situation is also applicable to machines that experience performance degradation over time due to mal-position or mal-alignment of jobs, abrasion of tools, and scraps of operations, etc. In this study, the integration of the two classes of scheduling problems is considered. We present a mathematical model to determine job-sequence and a position of a rate-modifying activity for the integration problem. Since the model is difficult to solve as the size of real problem being very large, we propose genetic algorithms. The performance of the algorithms are compared with optimal solutions with various problems.