• Journal of the Korean Society of Safety
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• v.31 no.1
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• pp.66-73
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• 2016

Lyocell fibers were used as a precursor in order to improve yield and strength of cellulose-based precursor while manufacturing activated carbon fiber(ACF). Lyocell fibers as a precursor for the preparation of ACF were surface-modified by reaction with 3-aminopropyltriethoxysilane(APTES) and pre-treated with KOH and H3PO4. Using aforementioned precursor, ACFs were prepared by a series of stabilization, carbonization and activation process at high temperatures. On each process, FT-IR, TGA, UTM and SEM were used to observe fibers' physical properties including structure and porous surfaces. FT-IR results proved that surface modification was achieved during stabilization, carbonization and activation process. TGA results during carbonization process found that surface modified fibers with APTES 0.02 mol(A2) showed higher thermostability, and extended pre-treatment increased yield. Especially, yield was found to have an increase of 10~20 wt% with surface modification during activation process. UTM results showed that tensile strength has the same order of concentration of APTES after surface modification, however, was found to show lower tensile strength than lyocell fibers after stabilization process. SEM results revealed that more homogeneous porosity control could be proceed after modifying the surface for the effective removal of hazardous substances.

• The Journal of the Korea Contents Association
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• v.16 no.7
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• pp.522-531
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• 2016

Extension of life expectancy and retirement of baby-boomers from 2010 made big population senior citizens, and concerns about retirement was heightened. Researches to remove the concerns about retirement found out that awareness for senior age life and financial preparation actions for retirement influence retirement life both directly and indirectly. This research identified the influence of financial retirement preparation on related variables, and analyzed its control effect on retirement and senior life perception, retirement preparation actions, and retirement satisfaction level. For that, from Nov 2015 to Feb 2016, this research surveyed 1,500 people from 20 to 69, by mailing or visiting with survey, noting purpose and process of research, eliminating 83 insufficient replies, and analyzing 1,417 surveys. This result shows the better retirement preparation, the more positive retirement and senior life perception, retirement preparation actions, and retirement satisfaction level. This research is significant as basic data for general and practical retirement preparation program development.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.12
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• pp.1785-1791
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• 2010

This paper describes a separable microfluidic device fabricated with PDMS (polydimethylsiloxane) and glass. The device is used for sample preparation involving cell lysis and the DNA purification process. The cell lysis was performed for 2 min at $80^{\circ}C$ in a serpentine-type microreactor ($20 {\mu}l$) using a Au microheater that was integrated with a thermal microsensor on a glass substrate. The DNA that was mixed with other residual products during the cell lysis process was then filtered through a new filtration system composed of microbeads (diameter: $50 {\mu}m$) and PDMS pillars. Since the entire process (sample loading, cell lysis reaction, DNA purification, and sample extraction) was performed within 5 min in a microchip, we could reduce the sample preparation time in comparison with that for the conventional methods used in biochemistry laboratories. Finally, we verified the performance of the sample preparation chip by conducting PCR (polymerase chain reaction) analysis of the chip product.

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.229-239
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• 2020

The purpose of this study was to help young people with mild intellectual disabilities with counseling and self-supporting life experiences. The topic of the counseling contents could be categorized as follows: "institutional life was clumsy and hard, but it was also full of memories," "my adolescent was aching, growing, and lonesome," "an irresistibie being," "independence process is filled with anxiety, excitement." In his process of going independent, the subject showed a strong will for the preparation for independence where he gets through the unfavorable situation surrounding the arduous and lonely independent process. This result proves the effectiveness of the therapeutic intervention based on the coping skills that meet the needs of the social situation for the adolescents who are discharged from institutions in their independence preparation and job search.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10b
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• pp.1817-1822
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• 1991

A method of reducing overhead caused by the processor synchronization process and common memory accesses in finely grained tasks is described. We propose a scheduler which considers the preparation time during searching to minimize the redundant accesses to shared memory. Since the suggested hardware (synchronizer) determines the access order of processors and bus arbitration simultaneously by including the synchronization process into the bus arbitration process, the synchronization time vanishes. Therefore this synchronizer has no overhead caused by the processor synchronization[l]. The proposed scheduler algorithm is processed in parallel. The processes share the upper bound derived by each searching and the lower bound function is built considering the preparation time in order to eliminate as many searches as possible. An application of the proposed method to a multi-DSP system to calculate inverse dynamics for robot arms, showed that the sampling time can be twice shorter than that of the conventional one.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.6
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• pp.271-275
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• 2001

We investigated preparation of 1-3 PZT composites for medical ultrasonic transducer array (briefly UTA) using micro pressing method. The proposed process was using pressing PZT green sheet by PMMA micro mold obtained from X-ray lithography. Microstructures, electriacl and electro-mechanical properties of fabricated composites were analyzed. Dielectric constant at 1kHz and thickness mode electro-mechanical coupling coefficient of $6.2mm{\times}6.2mm{\times}422{\mu}m$ UTA sample were 1754 and 51%, respectively. Microstructures of sintered PZT showed dense and uniform. And PZT phases were well crystallized. Micro pressing method is a mass productive process in case of using injection molded PMMA by batch type LIGA process.

• Journal of Sensor Science and Technology
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• v.24 no.2
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• pp.88-92
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• 2015

In order to study the semi-conductive characteristics of carbon black-filled ethylene-propylene-diene monomer (EPDM) composite film, which is used for measuring occlusal force, composite samples with volume ratios of carbon black to EPDM ranging from 30% to 70% were prepared. The process of making a composite film consists of two steps, which involve the preparation of a slurry composition and the fabrication of a thin film using solution casting and a lamination process. To prepare the slurry composition, we dispersed carbon black nanoparticles into an organic solvent before mixing with an EPDM solution in toluene. The mechanical and electrical properties of the resulting carbon black-filled EPDM film were then investigated, and the results showed that the electrical resistance of a film decreases with the increase in the carbon black content. Furthermore, improved elastic recovery was observed after cross-linking the EPDM.

• Journal of the Korea Society of Computer and Information
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• v.9 no.3
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• pp.109-113
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• 2004

This paper is to investigate the efficiency of the process of data preparation for existing data mining tools, and present a design principle for a new efficient data preparation system . We compare the often used data mining tools based on the access method to local and remote databases, and on the exchange of information resources between different computers. The compared data mining tools are Answer Tree, Clementine, Enterprise Miner, and Weka. We propose a design principle for an efficient system for data preparation for data mining on the distributed networks.

• Membrane Journal
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• v.6 no.2
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• pp.72-78
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• 1996

This paper was to investigate the preparation of quaternary ammonium polysulfone. The aminated polysullone (AMPS) as quaternary ammonium polysulfone was synthesized by two-step process. The first step involves the preparation of chloromethylated polysulfone (CMPS) which was produced by the introducion of chloromethyl group into polysulfone using chloromethyl methyl ether as a chloromethylation agent and zinc oxide as a catalyst. The second step, amination of CMPS was to give rise to AMPS using triethylamine.

• Korea Journal of Hospital Management
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• v.20 no.3
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• pp.45-55
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• 2015

While the influence of healthcare accreditation system to the quality improvement of hospitals has more increased, regarding the preparation costs for healthcare accreditation, it has never been empirically studied about the costs that are actually invested by hospitals. This study is going to determine the difficulties in the preparation process of accreditation and details of accreditation preparation costs for hospitals that participated in the healthcare accreditation system and acquired accreditation. The survey was performed in a self-reported form from February 28 to March 21 2014 for 189 acute hospitals accredited as a hospital from 2011 to February 2014. Of all questionaries of survey participants, 98 were recovered; the response rate was 51.9%. A total of 40 questionnaires were used except for 58 containing insincere answers. Main findings are followings: Firstly, findings showed that advanced general hospitals spent the most statistically significantly highest in terms of equipments and total costs among cost items for accreditation preparation. When accreditation preparation costs items were classified according to classification of hospitals, advanced general hospitals spent the most statistically significantly highest in the equipments and total costs. Also in terms of regional, Gyeonggi, Incheon regions were found to spend statistically significantly higher costs in the equipments costs. Secondly, as a result of the survey in the distribution of the total accreditation preparation costs, advanced general hospitals have disbursed the most out of all. However, the result in hospitals does not show significant difference to the expense of advanced general hospitals and that especially other regional hospitals spent higher costs. As such, all hospitals are under a heavy burden of higher costs on accreditation preparation, especially hospitals. The build-up of infrastructures by hospitals through an accreditation system consequently led to a higher initial investment; if the accreditation system is effective in improving the quality of health care and patient safety, appropriate responses are needed. In other words, financial support for investment costs needs to be given to allow hospitals to actively participate in the accreditation system.