• Journal of the Korean Society of Environmental Restoration Technology
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• 제23권3호
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• pp.91-104
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• 2020

This study was conducted to analyze the characteristics of defects according to the type of block and spatial type by quantitatively examining defects occurring in block pavement in apartment complex. According to the research results, depending on the type of block, defects have occurred 1,394.3ea/100㎡ in interlocking paver blocks, 464.8ea/100㎡ in clay brick paver blocks, and 235.1ea/100㎡ in shot blasted paver blocks. By space type, the defects were occurred 1,576.0ea/100㎡ on the access road paved by interlocking paver blocks and the defects were found 1,139.6ea/100㎡ in interlocking paver blocks, 235.1ea/100㎡ in shot blasted paver blocks, and 797.1ea/100㎡ in clay brick paver blocks, on the sidewalk. Also the defects are occurred 455.6ea/100㎡ on the resting space and 403.2ea/100㎡ on the gym space paved by clay brick paver blocks. Through the size analysis of the defects in the block paver, in the case 'peeling', the largest volume of 2,539.0㎣ on the sidewalk paved with shot blasted paver blocks, and 'Subsidence' occurred at the widest area of 2,096.0㎠ on the sidewalk where interlocking paver block was constructed. The difference in defect occurrence according to the type of block is considered to be influenced by the block production process, and the space type is considered to be caused the difference in the occurrence of defects according to the cause of construction and the usage pattern of residents. This study conducted a survey on defects in block and analyzed the defect characteristic according to paver material and space type. Base on this, it is judged that it can be used as an efficient basic data for material replacement, improvement, paver planning and construction in the future.

• Journal of Korean Society of Transportation
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• 제26권2호
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• pp.109-119
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• 2008

The number of card users has grown steadily after the adaption of smart card. Considering the diverse information from smart card data, the increase of card usage rate leads to various useful implications meaning in travel pattern analysis and transportation policy. One of the most important implications is the possibility that the data enables us to generate transit O/D tables easily. In the case of generating transit O/D tables from smart card data, it is necessary to filter data error and/or data missing. Also, the correction of data missing is an important procedure. In this study, it is examined to compute the level of data error and data missing, and to correct data missing for transit O/D generation.

• Journal of KIISE:Computer Systems and Theory
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• 제34권12호
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• pp.683-695
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• 2007

NAND flash memory-based file systems cannot store their system-related information in the file system due to wear-leveling of NAND flash memory. This forces NAND flash memory-based file systems to scan the whole flash memory during their mounts. The mount time usually increases linearly according to the size of and the usage pattern of the flash memory. NAND flash memory has been widely used as the storage medium of mobile devices. Due to the fact that mobile devices have unstable power supply, the file system for NAND flash memory requires stable recovery mechanism from power failure. In this paper, we present design and implementation of a new NAND flash memory-based file system that provides fast mount and enhanced stability. Our file system mounts 19 times faster than JFFS2's and 2 times faster than YAFFS's. The stability of our file system is also shown to be equivalent to that of JFFS2.

• Korean Journal of Food Science and Technology
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• 제24권6호
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• pp.563-567
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• 1992

Out of 74 food samples including pickled radish, soy sauce, Lactobacillus drinks, frozen sweets and snack confections, 60 samples were found to contain saccharin. The contents of sacchrain in terms of maximum and positive mean were 541, 306 ppm in pickled radish, 302, 153 ppm in soy sauce, 66, 37 ppm in Lactobacillus drinks, 90, 51 ppm in frozen sweets and 606, 285 ppm in snack confections, respectively. Most food items did not exceed the tolerance limit of saccharin while 70% of snack confections exceeded the limit, the average concentration being 2.9 times of the limit. Total daily intake of saccharin by Korean population for the period of $1985{\sim}1990$ was estimated to be $7{\sim}17\;mg/person$ from consumption data and $9{\sim}35\;mg/person$ from supply data. The intake level was $11{\sim}22%$ of acceptable daily intake for man (ADI) recommended by FAO/WHO whereas the level was slightly higher than that in USA or Japan. It is. therefore, judged that saccharin at the current pattern of usage will not exhibit any adverse effect on the safety of Korean population.

• Journal of the Korea Society of Computer and Information
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• 제16권9호
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• pp.19-26
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• 2011

Users want to receive customized service using users' personal device. To fulfill this requirement, the mobile device has to support a lot of functions. However, the mobile device has limitations such as tiny display screens. To solve this limitation problem and provide customized service to users, this paper proposes the environment to provide services by sharing resources and the method to recommend user-suitable resources among sharable resources. For the resource recommendation, This paper analyzes user's behavior pattern from usage history and proposes the method for recommending customized resources. This paper also shows that the approach is reasonable one for resource recommendation through the satisfaction evaluation.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권6호
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• pp.1881-1900
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• 2014

Since 802.11 wireless LANs are so widely used, it has become common for numerous access points (APs) to overlap in a region, where most of those APs are managed individually without any coordinated control. This pattern of wireless LAN usage is called the private OBSS (Overlapping Basic Service Set) environment in this paper. Due to frame collisions across BSSs, each BSS in the private OBSS environment suffers severe performance degradation. This study approaches the problem from the perspective of congestion control rather than noise or collision resolution. The retry limit, one of the 802.11 attributes, could be used for traffic control in conjunction with TCP. Reducing the retry limit causes early discard of a frame, and it has a similar effect of random early drops at a router, well known in the research area of congestion control. It makes the shared link less crowded with frames, and then the benefit of fewer collisions surpasses the penalty of less strict error recovery. As a result, the network-wide performance improves and so does the performance of each BSS eventually. Reducing the retry limit also has positive effects of merging TCP ACKs and reducing HOL-like blocking time at the AP. Extensive experiments have validated the idea that in the OBSS environment, reducing the retry limit provides better performance, which is contrary to the common wisdom. Since our strategy is basically to sacrifice error recovery for congestion control, it could yield side-effects in an environment where the cost of error recovery is high. Therefore, to be useful in general network and traffic environments, adaptability is required. To prove the feasibility of the adaptive scheme, a simple method to dynamically adjust the value of the retry limit has been proposed. Experiments have shown that this approach could provide comparable performance in unfriendly environments.

• The Research Journal of the Costume Culture
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• 제17권2호
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• pp.255-269
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• 2009

The purpose of this study was to understand the internet fashion shopping behavior of men in their 20s, and to develop the internet shopping website with situation-based clothing coordination services for male comsumer in their 20s. The study was implemented through a normative descriptive survey method using a questionnaire. The survey was conducted in April and May 2006, and the sample group consisted of 280 men in their 20s from Busan and the provinces of Gyeongnam and Gyeongbuk. The data was analyzed by following statistical methods: frequency analysis, one-way-ANOV A, and Scheffe's test. The results are as follow: first, regarding internet the usage trend of male consumers in their 20s, it was shown that they usually spent more than 15 minutes and less than 30 minutes for internet shopping the price range from their experiences of clothing purchases was relatively high for they bought jackets or suits was relatively high. Second, an analysis on men's pattern of clothing purchase showed that many respondents purchase single items such as shirts or pants online. Third, in terms of their experiences of online purchase of coordinated clothes, 69% said "none." Yet, they showed positive assessment to a question whether they are willing to purchase clothes by using a situation-based coordination service or a 1:1 online coordination services. Fourth, the relationship between consumers' reactions to online situation-based clothing coordination services and respondents' demographic characteristics showed statistically significant different results in terms of occupation.

• The Journal of Korean Obstetrics and Gynecology
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• 제30권3호
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• pp.65-78
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• 2017

Objectives: This study was aimed to develop a guideline for the application of diagnostic devices for menopausal syndrome. Methods: We conducted a literature review and a questionnaire survey on diagnostic devices including Digital Infrared Thermal Imaging (DITI), pulse diagnosis device, Heart Rate Variability (HRV), body composition analyzer, Yangdorak. Results: We retrieved some clinical values for usage of devices from the articles. Especially, DITI was useful to identify the pattern of body temperature distribution. The respondents answered that they diagnosed menopausal syndrome by using body composition analyzer (62.3%), DITI (60%), HRV (60%), pulse diagnosis device (45.7%), Yangdorak (34.3%). The respondents answered that they don't use diagnostic devices when they diagnosed menopausal syndrome because of absence of device, cost, difficulty of interpretation, substitution of another diagnostic method. After experts survey, it was recommended to use DITI, HRV, body composition analyzer. There was no consensus on the use of pulse diagnosis device, Yangdorak in diagnosing menopausal syndrome. Conclusions: We developed a guideline for the application of diagnostic devices for menopausal syndrome.

• Journal of Korea Water Resources Association
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• 제54권10호
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• pp.759-768
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• 2021

This work introduces a new approach that classifies individual household water usage by examining the characteristics of smart meter end-user demand data. Here, one of the most well-known unsupervised machine learning, K-means algorithm, is applied to classify water consumptions by each household. The intensity and duration of end-user demands are used as main features to determine the households with similar water consumption pattern. The results showed that 21 households are classified into 13 clusters with each cluster having one, two, three, or five houses. The reasoning why multiple households are classified into the same cluster is described in this paper with respect to the collected data and end-user water consumption behavior.

• The Korean Journal of Health Service Management
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• 제13권3호
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• pp.115-125
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• 2019

Objectives: Korea has been practicing the separation of dispensary from medical practice since 2000 as a national policy to prevent misuse or overuse of medicines. This study aimed to investigate prescription patterns from except pharmacies in order to determine the appropriateness of drug usage among those patients. Methods: Thirty-two pharmacies in the Yeongdong area of Gangwon Province were examined in this study. The same simulated patient complaining of cold symptoms for 3 days visited each pharmacy to obtain a prescription for medication. Results: At pharmacies prescribing medicine, steroids (53.1%) and antibiotics (50.0%) were used to treat the common cold. Duplicate prescriptions of drugs, such as antihistamines (47.0%) and decongestants (31.3%) were common. The average number of drug prescriptions was 6.59, and 53.2% of pharmacies had prescribed more than seven drugs. The average total cost of the prescriptions was 6,093 won, and the daily cost was 2,544 won. Conclusions: Steroids and antibiotics were frequently abused among patients whose medications had been prescribed by pharmacies. Also, there were a considerable number of drugs and duplicate prescriptions. The prices of the drugs were somewhat high.