• Journal of the Korean Data and Information Science Society
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• v.17 no.1
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• pp.95-113
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• 2006

The data resulting from a deterministic dynamic system may often appear to be random. However, it is important to distinguish a deterministic and a random processes for statistical analysis. In this paper, we propose a nonparametric test procedure to distinguish a noisy chaos from i.i.d. random process. The proposed procedure can be easily implemented by computer. We notice that the test is very effective to identify a low dimensional chaos process in some cases.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.3
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• pp.381-386
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• 1998

We frequently encounter stopped random sums when modelling queueing systems. We also notice occasional mishandling of stopped random sums in the literature. The purpose of this note is to prevent further mistakes by identifying and correcting typical mistakes about stopped random sums. As an example model, we use the two-phase M/G/1 queue with multiple vacations.

• Journal of Broadcast Engineering
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• v.23 no.4
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• pp.462-473
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• 2018

Steganography is to hide information in a media data so naturally that the other users can not notice the existence of hidden information. Data encryption focuses on the complex encoding methods of information data in order to make it difficult to decode the information even though the other users notice the existence of information. On the other hand, steganography methods concentrate on natural hiding information into other media. Since the other users do not recognize the existence of hidden information, the information can be better protected. This paper introduces the concept of image steganography that an image information is concealed into another image (cover image), and proposes a new discrimination method of steganography. This paper explains the spatial methods with LSB manipulation and frequency methods using DCT coefficients. Finally, this paper proposes a new discrimination method of image steganography by inspecting that an image information is correctly decoded.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.8
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• pp.663-671
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• 2013

Recently, the Wi-Fi Direct standard based on WLAN is getting more attention as a new technology for enabling D2D(Devide-to-Device) communications on mobile devices. However, due to limited power resource of mobile devices and, an energy inefficiency problem can be an issue. In order to solve this problem, the Wi-Fi Direct defines two power management schemes: Opportunistic scheme and Notice of Absence(NoA) scheme. However, there is no concrete description of which power management scheme would be better for when. In this paper, via comprehensive simulation studies using ns-3, we show that each scheme presents obviously different performance and energy efficiency according to data traffic patterns. We then propose more energy efficient way of dynamically switching the two power management schemes.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.19-25
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• 2008

We analyze the HACCP Prerequisites of National Veterinary Research and Quarantine Service (NVRQS), Korea Food and Drug Administration(KFDA), and US Food Safety and Inspection Service (FSIS) and recommend contents and ranges to be complemented and used for the preparation of guidelines. We used the HACCP Notice of the Processing Livestock Act, the HACCP Application Manual for Livestock Processing Plants, the HACCP Notice of the Food Sanitation Act, US GPO 9 CFR and 21 CFR, US FSIS Directive 11,000.1, and HACCP-based Inspection reference guide of Consumer Services, North Carolina Department of Agriculture. The Prerequisites of NVRQS and KFDA are composed of 66 and 84 items respectively, without detailed guidelines for their application. This may decisively affect the application in the field and the evaluation activities. Water supplies, washing and disinfection monitoring tools, and examining and correcting plan are required to be improved. If the standards of compliance of each Prerequisite item as well as performance guidelines are given, the application and evaluation will be performed more effectively. The evaluation items should be associated with Prerequisite operations such as non-compliance complement, self-evaluation, and record keeping. Hazards found during official inspection should be promptly controlled not to contaminate the work places and processing items. As the HACCP is expected to spread from farms to tables, the standardized Prerequisite program among the official governments should be prepared.

• The Journal of the Korea Contents Association
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• v.16 no.10
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• pp.467-476
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• 2016

With the development of information technology, Small office Home office(SOHO) is picking up. SOHO generally uses Wi-Fi. The wireless LAN environment using 802.11 protocol is easily affected by DoS attacks. To deal with these threats, there is Wireless Intrusion Detection System(WIDS). However, legacy products of WIDS cannot be easily used by SOHO because they are expensive and require management burden. In this paper, Smart WIDS for SOHO is proposed and implemented on Raspberry Pi2. And, it provides the interface for attack detection notice to android smart phone. Smart WIDS detects Masquerading DoS and Resource Depletion DoS based on IEEE 802.11 so that we notice the attempt of cracking Pre-shared Key(PSK), Man-In-The-Middle(MITM), and service failure.

• Journal of Korean Library and Information Science Society
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• v.9
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• pp.145-178
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• 1982

This is a survey of the circulation system for students in college & university libraries in Korea. The survey used a questionnaire with 14 questions on 6 items concerning the various aspects of the circulation system in 82 libraries responded among 85 college & university libraries as of 1981. The survey results discovered many problems needing improvement. The following list describes the measures needed to better the problems found in the survey results of 82 libraries. 1. 67.1% of the libraries shows the restricted volumes loaning less than 2 volumes, and 81.7% of the libraries shows the loan periods less than a week, but it is desirable to extend them, when comparing with the size of holdings and the higher educational system at present. 2. It is desirable that the number of a staff in charge of circulation works places one person per average 75-85 books borrowed a day, when calculating an adequate number of the staff on the basis of the correlation between books borrowed a day and number of the staff. 3. 59.8% of the libraries does not have reserved book system, but it is desirable to take it for increasing reliability about the circulation services. 4. More than half of the libraries takes a method of a public announcement on a notice-board for claims of overdue books, but it is desirable to send a claim notice to the individual in viewpoint of keeping their privacies. 5. More than half of the libraries to take the open access system uses a call slip, but it is desirable not to use it in viewpoint of simplicity and economical efficiency of the charging system, because of demanding the unnecessary records. 6. Most of libraries shows many problems of the charging system, especially in factors of the records and filing system, but it is desirable to improve it on the basis of 4 basic factors of the charging system, that is, simplicity, economical efficiency, promptitude and accuracy.

• Survey Research
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• v.11 no.3
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• pp.57-79
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• 2010

This study evaluated the policy performance of i) Public Notice of Critical Information, ii) Substantiation of Facts in Labeling and Advertising, iii) Temporary Injunctions, and iv) Advertisement Correcting Misrepresented Facts, which were main policies belonged to Fair Labeling and Advertising Act(hereinafter referred to as "FLA Act"). The data was collected by visiting 76 persons personally, who were consumer policy and law experts, labeling and advertising staffs of corporations, and persons in charge of policies including public officials dealing with consumer policies at Korea Fair Trade Commission, while using a structured questionnaire at the same time. The survey was performed to examine the general policy performance and evaluation the results of FLA Act by evaluation methods. The results of the analysis are comprehensively summarized as follows. There were differences in the ranking of policies evaluated by labeling and advertising staffs of corporations and persons in charge of policies according to evaluation methods, and, in Simple Evaluation, higher scores were gained compared to Weighted Evaluation which reflected weighted values or Fuzzy Evaluation. The result shows that evaluation results can vary in policy performance evaluation according to evaluation methods.

• Fashion & Textile Research Journal
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• v.4 no.2
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• pp.145-155
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• 2002

In order to investigate how upper limb motion gives influence on clothing, this study measured tests by following standards: Front Vertical motion, Side-Vertical motion, and Horizontal motion. For this study, the procedures in the order of alphabet are applied. A. Eeach of testee's pattern was copied by the motion with a method of tight fitting technique. B. Analyzing each of the size-change on measuring item. C. Studying the moving aspects at each datum points. The results shows that the biggest change can be found in the following items. 1) In vertical motion of F4 (the length to shoulder point from A-point) 2) In horizontal motion of F5 (the length to front-width point from A-point), the check-result gained by checking the notice between motions shows that the most noticeable items are F4 (the length to shoulder point from A-point), F5 (the length to front-width point from A-point), F6 (the length to armpit point from A-point), B7 (the length to side-waist point from B-point). In result of the study of datum point's movement by motion, the items which were measured with the longest on straight-distance in vertical motion are the front and rear-shoulder, and the rear-shoulder, front-armpit in horizontal motion each. In the movement of each datum points by length, the check-result gained by checking the notice between motions shows that the most remarkable item is the front-shoulder.

• The Korean Journal of Community Living Science
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• v.19 no.4
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• pp.559-568
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• 2008

Even though snacks or meals purchased by teenagers have dramatically increased in Korea, it has not been investigated whether teenagers know and take notice of the nutrition label. Therefore, in this study, we investigated the usefulness and utilization of food and nutrition labels amongst teenagers. Questionnaires were distributed 814 of junior-high school students and were completed by self-administrated questionnaires. Questionnaires included questions regarding general characteristics, perception and utilization of food and nutrition labels and degree of necessity and satisfaction on food products and nutrition labels. Data was analyzed with regards to sex and school year by using a SAS package program. Significant differences of each variable were tested by using the $x^2$-test, t-test and ANOVA. Only 4.4% of participants were well informed about food and nutrition labels, while 26.0% of them did not know about it. Most of participants(78%) perceived that food and nutrition labeling system is necessary but are not satisfied with it. More of them did not check the food and nutrition label when they purchased food. Students usually checked the food and nutrition label to know about the nutritional value, and additives. The survey showed that more than three quarters of participants take notice of the food and nutrition label on products whereas only 57.7% of them knew what the food and nutrition actually meant. This study showed that most teenagers did not know the food and nutrition label, didn't have right information and didn't use it. Therefore, it is necessary to include an educational program about the food and nutrition label in the school curriculum and that will help students use the nutrition label and help them choose healthy food.