• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.12
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• pp.1300-1310
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• 2003

In this paper, the performance of a multicarrier CDMA system using adaptive modulation and adaptive subchannel allocation scheme is analyzed in Rayleigh fading channel. The proposed adaptive modulator consists of modulation schemes using QPSK 16 QAM, 64 QAM and 256 QAM and constellations are pointed by Gray code. In addition, the threshold of the analysis is average E$\_$b//N$\_$o/ when the BER is 1 %. In the multicarrier system with adaptive subchannel allocation scheme, each DS waveform of user is transmitted over the K subchannels with the biggest fading among L subchannels. In case of the proposed system, total 4 subchannels are used and data are transmitted over 2 subchannels with the biggest fading, which results in the threshold of each channels is 5.2 dB, 9 dB, 13.2 dB and 8.4 dB, 12.2 dB, 16.3 dB. In the case of proposed system, the BER of 10$\^$-3/ is satisfied if average E$\_$b//N$\_$o/ is 8.1 dB. This is increased performance of 12.9 dB in comparison with conventional system. The BPS according to average channel is needed average E$\_$b//N$\_$o/ of about 15 dB in 7 bit. In the case of subchannel error, the BER of 10$\^$-3/ is 13.6 dB and is declined about 5.5 dB.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.65-73
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• 2019

The MODIS (Moderate Resolution Imaging Spectroradiometer) data in Hierarchical Data Format (HDF) have been processed using the Geospatial Data Abstraction Library (GDAL). Because of a relatively large data size, it would be preferable to build and install the data analysis tool with greater computing performance, which would differ by operating system and the form of distribution, e.g., source code or binary package. The objective of this study was to examine the performance of the GDAL for processing the HDF files, which would guide construction of a computer system for remote sensing data analysis. The differences in execution time were compared between environments under which the GDAL was installed. The wall clock time was measured after extracting data for each variable in the MODIS data file using a tool built lining against GDAL under a combination of operating systems (Ubuntu and openSUSE), compilers (GNU and Intel), and distribution forms. The MOD07 product, which contains atmosphere data, were processed for eight 2-D variables and two 3-D variables. The GDAL compiled with Intel compiler under Ubuntu had the shortest computation time. For openSUSE, the GDAL compiled using GNU and intel compilers had greater performance for 2-D and 3-D variables, respectively. It was found that the wall clock time was considerably long for the GDAL complied with "--with-hdf4=no" configuration option or RPM package manager under openSUSE. These results indicated that the choice of the environments under which the GDAL is installed, e.g., operation system or compiler, would have a considerable impact on the performance of a system for processing remote sensing data. Application of parallel computing approaches would improve the performance of the data processing for the HDF files, which merits further evaluation of these computational methods.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.322-326
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• 2014

According to Centers for Disease Control and Prevention (CDC, USA) recently it was reported that the children (< 5 year-old children) were more susceptible to Foodborne-illness. Confectionery products should be strictly controlled because they are children-preferred foods. Ministry of Food and Drug Safety (MFDS, South of Korea) tried to monitor contamination of organisms in confectionery products (such as biscuits, candies, chewing gums and ice candies) distributed in South Korea. MFDS evaluated the levels of indicator organisms: total aerobic bacteria, coliforms, Escherichia coli as well as the levels of food-borne illness organisms: Staphylococcus aureus, Bacillus cereus, Clostridium perfringens. Experimental plans for microbiological test were in accordance with the International Commission on Microbiological Specifications for Food (ICMSF). For this study, 1,005 samples were collected and from Seoul and Gyeongin region, South Korea. The average level of total aerobic bacteria in 1,005 samples was 1.7 log Colony Forming Unit(CFU)/g and the detection rate was 26.8%. The average level of Bacillus cereus was detected in 1.7 log CFU/g and the rate was 0.9%. There was no detection of coliforms, Escherichia coli, Staphylococcus aureus and Clostridium perfringens. The results of this study will be provided as the basic data to set the reasonable microbiological criteria of Korea Food Code.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.323-334
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• 2008

This experiment was carried out to analyze for pesticide residues in 17 different types of the special of geographical indication. We purchased 3 cereal grains, nuts and seeds, 3 fruits, 8 vegetables, mushrooms and other plants (Korean medicines) mainly at the agricultural cooperative's joints markets. Total 209 pesticides including multi-analysed pesticides (204) and single-analysed pesticides (5 ; acephate, methamidophos, monocrotophos, omethoate, vamidothion) were analysed with a GC/MS/MS, an HPLC/UVD (PDA) and a GC/FPD. No. 83 method and single-analysed method (Screening of multi-pesticide residue in the special products of geographical indication) of Korea Food Code was selected for validation in recovery and interferences of matrice. The results were as follows: among the selected 17 the special products, the residual pesticides were detected in 8 types of the special products (40 in 302 samples, detection ratio; 13.2%). All of the samples were not detected over MRLs, but tebuconazole, procymidone and isoprothioran were detected with considerable high frequency. These results could be used as KFDA official methods for the analysis of pesticide residues in foods and reference data will be provided to the related institutions.

• Culinary science and hospitality research
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• v.22 no.5
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• pp.64-81
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• 2016

The study, based on existing studies, explored influencing relationship, suggesting app service quality and user reviews as previous elements to affect use satisfaction about users' comments based on big data and reuse intention. The study includes a comparative analysis of existing studies. Based on such analysis results, the authors looked into app service quality elements perceived by gourmet restaurant app users and the role of user reviews, and suggested practical implications that can help the development and operation of gourmet restaurant app contents. The study subjects were male and female consumers who over 20 years old throughout Korea who had not a searched smartphone gourmet restaurant app in the three months preceding the survey. The subjects were selected from consumers who search the restaurantsby using restaurant apps like Mango plate, Dining code, Hot place, and selecting restaurants. Among them, consumers with experience using restaurants were finally selected for the survey. According to the results, reliability, informativity, and system capability, among service quality, had positive influences on app use satisfaction, while design and mobility had no effect. App use satisfaction had positive influences on app reuse intention. User comment informativity played a controlling role. The study explored the importance of app service quality and user review informativity as elements that affect continued use of gourmet restaurant apps by dining-out consumers.

• Geophysics and Geophysical Exploration
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• v.14 no.1
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• pp.7-17
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• 2011

We have developed an inversion code for three-dimensional (3D) resistivity tomography including the anisotropy effect. The algorithm is based on the finite element approximations for the forward modelling and Active Constraint Balancing method is adopted to enhance the resolving power of the smoothness constraint least-squares inversion. Using numerical experiments, we have shown that anisotropic inversion is viable to get an accurate image of the subsurface when the subsurface shows strong electrical anisotropy. Moreover, anisotropy can be used as additional information in the interpretation of subsurface. This algorithm was also applied to the field dataset acquired in the abandoned old mine area, where a high-rise apartment block has been built up over a mining tunnel. The main purpose of the investigation was to evaluate the safety analysis of the building due to old mining activities. Strong electrical anisotropy has been observed and it was proven to be caused by geological setting of the site. To handle the anisotropy problem, field data were inverted by a 3D anisotropic tomography algorithm and we could obtain 3D subsurface images, which matches well with geology mapping observations. The inversion results have been used to provide the subsurface model for the safety analysis in rock engineering and we could assure the residents that the apartment has no problem in its safety after the completion of investigation works.

• The Journal of Korean Society for School & Community Health Education
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• v.14 no.3
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• pp.27-40
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• 2013

Objectives: This study was conducted at a request for cooperation through an analysis of the effect of toothbrushing facilities at a public health center in Seongdong-gu. Also, with the aim of furnishing basic data to the proposal of a program for improving the ability of school aged children in managing oral cavities and developing a correct toothbrushing habit, the study conducted an investigation of how toothbrushing facilities affect change in the oral environment management ability and behavior of oral health care. Methods: From among elementary schools located in Seongdong-gu, Seoul the study selected A Elementary School where toothbrushing facilities were established and have been operated since 2008, B Elementary School in an adjacent region within the jurisdiction of Seongdong-gu where the demographic environment was similar among schools where toothbrushing facilities were newly established in 2012, and C Elementary School without toothbrushing facilities. Then the study was aimed at first grade students of the schools and an investigation was carried out from April to December 2012. Through a dental checkup, the study evaluated the teeth and periodontal health conditions, and a test of the oral environment management ability was undertaken three times. Regarding change of oral health care behavior, the study carried out a self-recording survey. Results: 1. Concerning decayed and filled tooth(dft) and decayed and filled surface (dfs), A Elementary School where toothbrushing facilities have been established and operated from the past showed a relatively lower decayed, missing, and filled teeth index than B Elementary School where toothbrushing facilities were established in 2012 or C Elementary School without toothbrushing facilities; however, there was no significant difference (p>0.05). For CPI, there was no significant difference by school; however, in looking into the difference between boy students and girl students, Code (0) was discovered higher in boy students whereas Code (1) was shown higher in girl students. 2. In the PHP index test in accordance with the existence of toothbrushing facilities before the installation of toothbrushing facilities, for A Elementary School where toothbrushing facilities have been established and operated from the past, the school recorded 4.28 points whereas B Elementary School where the facilities were established in 2012 recorded 3.51 points. Meanwhile C Elementary School without the facilities posted 4.30 points. Therefore there was a statistically significant difference according to the existence of toothbrushing facilities (p<0.05). 3. In a comparison of teeth health care behavior according to the existence of toothbrushing facilities, the number of answers that the respondent did not brush their teeth after lunch over the past one week was higher in B Elementary School and C Elementary School where there were no toothbrushing facilities. Regarding the average number of brushing after lunch for one week, it was discovered higher in A Elementary School (p<0.01). 4. In change of teeth health care behavior before and after the establishment of toothbrushing facilities, the case of answering that the respondents did not brush their teeth after lunch for one week increased more after establishment than before establishment. Also the average number of teeth brushings after lunch for one week decreased further after the establishment of toothbrushing facilities; however, it did not show a significant difference (p>0.05). One of the reasons that they do not brush their teeth, "the lack of a place", decreased significantly after establishment than before establishment (p<0.05), whereas the answer, "because their friends do not brush their tooth" increased greatly after establishment than before establishment; however, there was no significant difference (p>0.05). 5. In the comparison of the degree of knowledge about dental health according to the existence of toothbrushing facilities, the degree of knowledge about dental health was shown significantly higher in A Elementary School with toothbrushing facilities than in B Elementary School and C Elementary School where there were no toothbrushing facilities (p<0.01). Conclusions: Given the above results, it is difficult to attract change in behavior only with an environmental improvement; therefore, it is deemed necessary to develop an educational program that will help children to make a habit of oral health care not only through a school but also through a related policy and financial support of government organizations as well as the construction of the basis of a systematic and consistent cooperative system with relevant organizations.

• Journal of Korean Academy of Nursing Administration
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• v.1 no.2
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• pp.268-284
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• 1995

This study was designed to test effects of nursing ethics education (NEE) on moral reasoning and ethical decision making of subjects. This NEE that was teached for 10 hours course was composed of these : Nurses' ethical code, moral responsibility, Moral value and professional accountability, Respect for human life, General ethics, Theory and Norms of biomedical ethics, Ethical decision making model and Discussion about hypothetical ethical dilemmas Twenty-five senior student nurses were sampled from four year college of nursing from Nov. 3rd, 1993 to Nov. 24th, 1993. Data were collected through self-reported questionnaires included two kinds of tests. Rest's Defining Issues Test was adopted to measure the stage of moral development, which was classified with the stage 2 (instrumental relativist orientation), the stage 3 (interpersonal concordance), the stage 4 (law and order), the stage 5A (societal consensus), and the stage 5B (intuitional humanism), the stage 6 (universal ethical practice). In particular, the level of principled thinking (P) was measured by summing these scores of the stages 5A, 5B, and 6. The possible range of P is 0 to 95. As for measuring the levels of morality and nursing dilemma, Crisham's Nursing Dilemma Test was adopted. This test generated the morality score(MS) and the dilemma score (DS). The data were analyzed by t-test, ANOVA, Kruskal-Wallis test, Mc Nemar's test and Pearson correlation coefficients. The results were as follows ; 1. For the Moral Reasoning both before and after NEE, The Mean score of the stage 5A was significantly higher than that of other stages.(P=0.0001) Before NEE, the mean score of the stage 4 was significantly different from stage 2, 3, 5A, and after NEE, different from stage 2, 5B,6. 2. The analysis of change of moral development level revealed that the score of stage 4 increased after NEE.(P=0.0004) 3. The Effect of NEE for the mean score of 5A, 6, P after education was significantly different by birth place. 4. With regard to the five dilemmas postulated such as forcing medication performing cardiac pulmonary resuscitation, reporting a medication error, informing diagnosis to terminally ill adult, and providing new-nurse orientation, the mean score of the MS and the DS was no significant difference with general characteristics of the students. Effect of NEE morality score and dilemma score after education was no significant difference. 5. As for the correlations between moral reasoning and decision making, the score of the stage 2, 5A, 6, DS was positively correlated with the scores of before and after. Positive correlation was also observed between the scores of stage 2 and stage 4, stage 3 and 6. On the other hand, the score of P was negatively correlated with the scores of stage 2 and of stage 4 and of stage 5A. The score of the stage 5A was also negatively correlated with the score of the sge 6.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.2
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• pp.357-367
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• 2018

As information technology of modern society develops, various malicious codes with the purpose of seizing or destroying important system information are developing together. Among them, ransomware is a typical malicious code that prevents access to user's resources. Although researches on detecting ransomware performing encryption have been conducted a lot in recent years, no additional methods have been proposed to recover damaged files after an attack. Also, because the similarity comparison technique was used without considering the repeated encryption, it is highly likely to be recognized as a normal behavior. Therefore, this paper implements a filter driver to control the file system and performs a similarity comparison method that is verified based on the analysis of the encryption pattern of the ransomware. We propose a system to detect the malicious process of the accessed process and recover the damaged file based on the cloud storage.

• Journal of IKEEE
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• v.1 no.1 s.1
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• pp.101-110
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• 1997

SVLIW processor architectures can resolve resource collisions and data dependencies between the instructions while scheduling VLIW instructions at run-time. As a result, long NOP word instructions can be removed from the object code produced for the processor. Thus, the occurrence of cache misses on the SVLIW processor would be lesser than that on the same cache size VLIW processor. Less frequent cache misses on the SVLIW processor would incur less frequent memory access, and thus, the total execution cycles to complete an application would be shortened compared with cases on the VLIW processor. Such a feature eventually compromises effects of longer instruction pipeline stages than those of the VLIW processor. In this paper, we formulate and compare two execution cycle models of the two architectures. A simulation results show that the longer memory access cycles when cache miss occurs, the total execution cycles of SVLIW processor would be shorter than those of VLIW processor.