• Journal of KIISE:Databases
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• v.28 no.3
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• pp.494-511
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• 2001

In the environment that database management systems manage disk spaces for storing databases directly, this paper proposes a correct and efficient scheme of performing pending actions for the removal of database files. As for performing pending actions, upon performing recovery, the recovery process must identify unperformed pending actions of not-yet-terminated transactions and then perform those actions completely. Making the recovery process identify those actions through the analysis of log records in the log file is the basic idea of this paper. This scheme, as an extension of the execution of transactions, fuzzy checkpoint, and recovery of ARIES, uses the following methods: First, to identify not-yet-terminated transactions during recovery, transactions perform pending actions after writing 'pa_start'log records that signify both the commit of transactions and the start of executing pending actions, and then write 'eng'log records. Second, to restore pending-actions-lists of not-yet-terminated transactions during recovery, each transaction records its pending-actions-list in 'pa_start'log record and the checkpoint process records pending-actions-lists of transactions that are decided to be committed in 'end_chkpt'log record. Third, to identify the next pending action to perform during recovery, whenever a page is updated during the execution of pending actions, transactions record the information that identifies the next pending action to perform in the log record that has the redo information against the page.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.3
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• pp.294-300
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• 2019

To investigate the inhibition effect on pathogenic microbes and the antimicrobial resistance of probiotics, a total of 140 probiotics were isolated from 35 kinds of Korean commercially available Kimchi. Of those, L. plantarum was identified from 53 strains (37.9%), E. faecium from 27 strains (19.3%), and L. rhamnosus from 7 strains (5.0%) using 16S rRNA gene sequencing. Sixty nine strains (49.3%) showed overall antimicrobial activity against pathogenic microbes, namely S. Typhi, S. Enteritidis, E. coli O157:H7, S. flexneri, NAG Vibrio, Listeria monocytogenesis, Y. enterocolitica, S. aureus, S. pyogenes, G. vaginalis, C. albicans, and P. acne. The proportions of L. plantarum, E. faecium, and L. rhamnosus strains to pathogenic microbes were 75.5%, 40.7%, and 28.6%, respectively. In addition, a resistance test with 18 antimicrobial agents using a disk diffusion assay revealed a resistance incidence of 98.6% for nalidixic acid, 83.6% for streptomycin, 75.7% for gentamicin 73.6% for vancomycin, 72.1% for norfloxacin, and 67.9% for ciprofloxacin. In conclusion, L. plantarum, L. sakei, and E. faecium strains with various antimicrobial activities and broad antibiotic resistance are useful for treating diarrhea in long-term inpatients and for the alternative use for treating Candida species female vaginitis.

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.5
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• pp.293-299
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• 2007

Intelligent pipeline inspection gauges (PIGs) are inspection vehicles that move along within a (gas or oil) pipeline and acquire signals (also called sensor data) from their surrounding rings of sensors. By analyzing the signals captured in intelligent PIGs, we can detect pipeline defects, such as holes and curvatures and other potential causes of gas explosions. There are two major data access patterns apparent when an analyzer accesses the pipeline signal data. The first is a sequential pattern where an analyst reads the sensor data one time only in a sequential fashion. The second is the repetitive pattern where an analyzer repeatedly reads the signal data within a fixed range; this is the dominant pattern in analyzing the signal data. The existing PIG software reads signal data directly from the server at every user#s request, requiring network transfer and disk access cost. It works well only for the sequential pattern, but not for the more dominant repetitive pattern. This problem becomes very serious in a client/server environment where several analysts analyze the signal data concurrently. To tackle this problem, we devise a fast in-memory cache manager, called T-Cache, by considering pipeline sensor data as multiple time-series data and by efficiently caching the time-series data at T-Cache. To the best of the authors# knowledge, this is the first research on caching pipeline signals on the client-side. We propose a new concept of the signal cache line as a caching unit, which is a set of time-series signal data for a fixed distance. We also provide the various data structures including smart cursors and algorithms used in T-Cache. Experimental results show that T-Cache performs much better for the repetitive pattern in terms of disk I/Os and the elapsed time. Even with the sequential pattern, T-Cache shows almost the same performance as a system that does not use any caching, indicating the caching overhead in T-Cache is negligible.

• KEPCO Journal on Electric Power and Energy
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• v.4 no.1
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• pp.19-24
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• 2018

The long-term research and development for the production of domestic blades has been consistently performed. As the direct and indirect results of its nationwide technologies in precision casting have been improved as well as maintenance costs for turbine machinery has been reduced. Whereas, there are still not a few concerns about the reliability of newly manufactured blades in spite of the quality certificate in metallurgical and mechanical properties. A spin tester is a machine that gives centrifugal loading to a rotating part, and its practical application is the overspeed test that is usually used to check the quality of products. A new spin rig has been constructed in KEPCO Research Institute for the purpose of evaluating the reliability of blades. In this paper, the test methodology for low cycle fatigue damage mechanism as well as the overspeed test for newly developed blades is described, and their reliability is evaluated too.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.1
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• pp.26-31
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• 2007

In this study, A BED(Binary ECG description) based binary ECG conversion system is that supports the conversion of a binary ECG format into XML-based HL7 aECG for interoperability of ECG. HL7 aECG is a XML based standard lot interoperability of ECG waveform. However, it is difficult for beginners to write the BED document of binary BED conversion system in XML. We implement a BED Studio on the Java Servlet engine that allows beginners to write BED documents more easily. Our system consists of three parts: Visual Editor, Text Editor, and Format Checking Viewer. Format Checking Viewer support users to detect the format errors in the XML files, so-called BED documents, that describe the data format of the targer binary ECG file in the BED-based binary ECG conversion system, so may reduce the format errors in BED documents.

• Journal of Food Hygiene and Safety
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• v.11 no.4
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• pp.315-321
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• 1996

Various antimicrobial drug screen tests have been used in order to ensure food safety. However, the conventional screen tests, the Swab Test on Premises(STOP, USA), the Calf Antibiotic and Sulfa Test(CAST, USA) and the European Economic Community 4-plate Test(FPT, EU) are not sufficiently rapid or sensitive enough to detect low levels of sulfa drugs in meat. We developed a new screen test kit for the determination of the antimicrobial residues in meat called the Bacillus megaterium Disk Assay(BmDA). A comparison of BmDA with the older screen tests showed BmDA was as good as the older ones with several advantages. The new test kit is faster-it can be read in 4∼6 hours instead of 16∼18 hours. Moreover, BmDA can discriminate sulfa drugs from other antimicrobial drugs because p-aminobenzoic acid countacts the inhibiting action of sulfa drugs. Minimum detectable levels of sulfa drugs were significantly improved at the lever of 0.025*0.1 pp, compared with the level of 1.0 ppm in FPT. A comparison of BmDA with the older screen tests in HPLC confirmed meat samples exceeded the Korean tolerance value of 0.1 ppm showed BmDA was the most sensitive in the microbiological screen tests. As the microbiological screen tests have already known, a person familiar with simple laboratory techniques should have no difficulty in using it to detect antimicrobial residues in meat. This would be a simple, economic method of antimicrobial residues detection which might be succesfully used by many laboratories.

• Journal of KIISE:Databases
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• v.29 no.6
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• pp.502-512
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• 2002

Most of previous replication schemes assume lazy schemes, which asynchronously propagate replica updates to other nodes after the updating transaction commits. While lazy schemes are novel in the sense that they can resolve high deadlock frequencies of eager schemes, they suffer from the fact that users should be responsible for the data consistency. Recently replication schemes based on the messaging order of group communication have been studied. They can reduce the deadlock frequencies using the messaging order, but they have another problem of increasing execution overhead of aborted transactions at high degree of concurrency. This is because the sender node validates global serializability after multicasting replica update messages to other nodes. In this paper, we propose an efficient eager replication scheme for reducing the number of messaging and overhead of aborted transactions significantly. The proposed scheme validates any conflicts before multicasting and does not multicast when there is any conflict; hence, it can exploit performance improvement by alleviating the message traffic for replica update or by reducing the number of disk accesses and locking delay due to aborted transactions.

• Journal of KIISE:Databases
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• v.29 no.6
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• pp.500-500
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• 2002

Most of previous replication schemes assume lazy schemes, which asynchronously propagate replica updates to other nodes after the updating transaction commits. While lazy schemes are novel in the sense that they can resolve high deadlock frequencies of eager schemes, they suffer from the fact that users should be responsible for the data consistency. Recently replication schemes based on the messaging order of group communication have been studied. They can reduce the deadlock frequencies using the messaging order, but they have another problem of increasing execution overhead of aborted transactions at high degree of concurrency. This is because the sender node validates global serializability after multicasting replica update messages to other nodes. In this paper, we propose an efficient eager replication scheme for reducing the number of messaging and overhead of aborted transactions significantly. The proposed scheme validates any conflicts before multicasting and does not multicast when there is any conflict; hence, it can exploit performance improvement by alleviating the message traffic for replica update or by reducing the number of disk accesses and locking delay due to aborted transactions.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.3
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• pp.557-567
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• 2018

There are currently various file encryption solutions for encrypting and storing files on disk. However, the existing file encryption solutions handle encryption and decryption all at once by file or directory. In this paper, we propose a system call supporting partial encryption function of the file. The user sets the encryption information with the system call interface at a portion where encryption of the file data is desired. And then the user writes file data, the data is encrypted and stored. Also if the user sets decryption information and reads the file data, the necessary part is decrypted by applying the set information. For the proposed system call, It consists of inspection module, management module, encryption module, decryption module, and HMAC module as per required system call. And it was implemented on the Linux environment. Also the operation of implemented system call was verified on the development board, and the performance was analyzed by measuring performance speed.

• Journal of Digital Policy
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• v.3 no.1
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• pp.21-25
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• 2024

This is a case study that sought to consider whether taping, which focuses on instability of the sacroiliac joint, is a potential intervention method that may be helpful for low back pain. In the case of a 58-year-old participant, we summarized the notable results from a taping training session that a man with a history of back surgery due to disc herniation and stenosis participated in to reduce ongoing pain. As an intervention method, tape was applied between the 2nd and 4th sacrum on both sides from the spinous tuberosity. It was stretched to a tension of 80% and attached past the sacroiliac joint, and then the ends were raised at about 45° on both sides and attached toward the gluteus medius muscle. Then, along the erector spinae muscle from the iliac crest. Bilateral taping up to the level of the 10th rib was applied. Through this intervention, positive case results were observed from both VAS and ODI test tools, with VAS recorded as 5 to 0 and disability index recorded as 13 to 0, respectively.