• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.307-307
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• 2006

The reduction behavior of silver ions to silver nanoparticles is an important research topic in polymer/silver salt complex membranes for facilitated olefin transport, because it has a significant effect on the long-term stability of membrane performance. In this study, the effects of solvent on the formation of silver nanoparticles and long-term membrane performance in polymer/silver salt complex membrane were investigated. This effect was assessed for the complexes of poly(N-vinyl pyrrolidone) $(PVP)/AgBF_{4}$ with the use of ionic liquid (IL), acetonitrile (ACN) and water as a solvent. Membrane performance test shows that long-term stability is strongly dependent on the kind of solvent and arranged: IL > ACN >> water.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.2
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• pp.12-18
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• 1997

An efficient synthesis method of cellular architecture FPgA is proposed in this paper. To generate a logical representation called complex term which is to be directly mapped onto the cellular architecture FPGA, and SO or ESOP minimization tool was used in previous methods. Instead, we use a logic function transformed into BDD (binary decision diagram) in the actual generation of the complex temrs. In this process it estimates the cost(i.e. the number of complex terms) for three branches, 0-branch and 1-branches. This process is continued over the whole BDD to do such computation, and we observed that the number of complex terms has been reduced compared to the previous results.

• Journal of Environmental Impact Assessment
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• v.8 no.2
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• pp.1-8
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• 1999

The research centers on the concentration profile and risk assessment of toxic metals for ambient air in Taejon industrial complex. Airborne concentrations of each toxic metal for risk assessment were obtained from 2-year sampling by high volume air sampler and analysis by ICP-MS and ICP-AES in the complex. The long-term arithmetic mean of human carcinogen, arsenic, hexavalent chromium and nickel subsulfide was 5.53, 2.16 and $3.46ng/m^3$ while the mean of probable human carcinogen, beryllium, cadmium and lead was 0.08, 2.35, $293.29ng/m^3$, respectively. And the long-term arithmetic mean concentration of non-carcinogenic metal, manganese was $55.91ng/m^3$. The point risk estimate for the inhalation of carcinogenic metals was $3.6{\times}10^{-5}$, which was higher than a risk standard of $10^{-5}$. About 75% of the cancer risk was to the inhalation of human carcinogen, arsenic. Thus, it is necessary to properly manage arsenic risk in Taejon industrial complex. The point hazard index by the inhalation of manganese was 1.1. Therefore, an investigation into Taejon industrial complex is needed to obtain more fine long-term concentration data for airborne non-carcinogenic metals including manganese.

• International Journal of Knowledge Content Development & Technology
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• v.9 no.3
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• pp.23-41
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• 2019

This study combines the concept of degree centrality in complex network with the Term Frequency $^*$ Proportional Document Frequency ($TF^*PDF$) algorithm; the combined method, called PMCN (PDF-Modified similarity and Complex Network), constructs relationship networks among sentences for writing news summaries. The PMCN method is a multi-document summarization extension of the ideas of Bun and Ishizuka (2002), who first published the $TF^*PDF$ algorithm for detecting hot topics. In their $TF^*PDF$ algorithm, Bun and Ishizuka defined the publisher of a news item as its channel. If the PDF weight of a term is higher than the weights of other terms, then the term is hotter than the other terms. However, this study attempts to develop summaries for news items. Because the $TF^*PDF$ algorithm summarizes daily news, PMCN replaces the concept of "channel" with "the date of the news event", and uses the resulting chronicle ordering for a multi-document summarization algorithm, of which the F-measure scores were 0.042 and 0.051 higher than LexRank for the famous d30001t and d30003t tasks, respectively.

• Bulletin of the Korean Mathematical Society
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• v.50 no.1
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• pp.233-240
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• 2013

In this paper, we use the elementary method and the theory of complex functions to study the computational problem of the fourth power mean of the generalized two-term exponential sums, and give two exact identities for them.

• Proceedings of the Membrane Society of Korea Conference
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• 1992.10a
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• pp.55-56
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• 1992

본 연구에서는 산/염기 수용액의 탈수분리에 이미 complex site를 가진 막을 투과증발에 응용하는 것이 아니라, 공급액으로 사용되는 산/염기와 complex를 형성할수 있는 작용기를 가진 막을 그들 수용액의 탈수분리에 응용함으로써 형성된 complex site로 분리성능의 향상을 도모하였다. 또한, 분리대상물내의 한성분이 couter ion으로 작용하는 점을 이용하여 long-term stability의 문제도 해결하고자 하였다.

• Macromolecular Research
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• v.15 no.2
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• pp.167-172
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• 2007

The reduction behavior of silver ions to silver nanoparticles is an important topic in polymer/silver salt complex membranes to facilitate olefin transport, as this has a significant effect on the long-term performance stability of the membrane. In this study, the effects ofthe solvent type on the formation of silver nanoparticles, as well as the long-term membrane performance of a solid polymer/silver salt complex membrane were investigated. These effects were assessed for solid complexes of poly(N-vinyl pyrrolidone) $(PVP)/AgBF_4$, using either an ionic liquid (IL), acetonitrile (ACN) or water as the solvent for the membrane preparation. The membrane performance test showed that long-term stability was strongly dependent on the solvent type, which increased in the following order: IL > ACN >> water. The formation of silver nanoparticles was more favorable with the solvent type in the reverse order, as supported by UV-visible spectroscopy. The poor stability of the $(PVP)/AgBF_4$ membrane when water was used as the solvent might have been due to the small amount of water present in the silver-polymer complex membranes actively participating in the reduction reaction of the silver ions into silver nanoparticles. Conversely, the higher stability of the $(PVP)/AgBF_4$, membrane when an IL was used as the solvent was attributable to the cooperative coordination of silver ions with the IL, as well as with the polymer matrix, as confirmed by FTIR spectroscopy.

• Journal of Korean Academy of Nursing
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• v.33 no.2
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• pp.275-283
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• 2003

Purpose: This study was to classify elderly in long-term care hospitals for using Resource Utilization Group(RUG-III) and to consider feasibility of payment method based on RUG-III classification system in Korea. Method: This study designed by measuring resident characteristics using the Resident Assessment Instrument-Minimum Data Set(RAI-MDS) and staff time. The data were collected from 382 elderly over sixty-year old, inpatient in the five long-term care hospitals. Staff time was converted into standard time based on the average wage of nurse and aids. Result: The subjects were classified into 4 groups. The group of Clinically Complex was the largest(46.3%), Reduced Physical Function(27.2%), Behavior Problem(17.0%), and Impaired Cognition(9.4%). The average resource use for one resident in terms of care time(nurses, aids) was 183.7 minutes a day. Relative resource use was expressed as a case mix index(CMI) calculated as a proportion of mean resource use. The CMI of Clinically Complex group was the largest(1.10), and then Reduced Physical Function(0.93), Behavior Problem(0.93), and Impaired Cognition(0.83) followed. The difference of the resource use showed statistical significance between major groups(p<0.0001). Conclusion: The results of this study showed that the RUG-III classification system differentiates resources provided to elderly in long-term care hospitals in Korea.

• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.183-198
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• 2003

We highlight the alternative presentation of the Cauchy-Riemann conditions for the analyticity of a complex variable function and consider plane equilibrium problem for an elastic transversely isotropic layer, in finite deformation. We state the fundamental problems and consider traction boundary value problem, as an example of fundamental problem-one. A simple solution of“Lame's problem”for an infinite layer is obtained. The profile of the deformed contour is given; and this depends on the order of the term used in the power series specification for the complex potential and on the material constants of the medium.

• Clinics in Shoulder and Elbow
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• v.23 no.1
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• pp.20-26
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• 2020

Background: High complication rate after open reduction and internal fixation can lead to use of primary total elbow replacement (TER) in treatment of complex distal humerus fractures in elderly patients. The purpose of this study was to investigate the short-term outcomes and complications after primary TER in patients with complex distal humerus fracture. Methods: Nine patients with acute complex distal humerus fracture were treated by primary TER using the semiconstrained Coonrad-Morrey prosthesis. The mean age of patients was 72.7 years (range, 63-85 years). Clinical and radiographic outcomes were evaluated over a mean follow-up of 29.0 months (range, 12-65 months) using visual analog scale (VAS) score for pain; Mayo elbow performance score (MEPS); Quick Disabilities of the Arm, Shoulder, and Hand (Quick-DASH) score; and serial plain radiographs. Complications were also evaluated. Results: At the final follow-up, mean VAS, MEPS, and Quick-DASH scores were 1.2, 80.5, and 20, respectively. The mean range of motion was 127.7° of flexion, 13.8° of extension, 73.3° of pronation, and 74.4° of supination. There was no evidence of bushing wear or high-grade implant loosening on serial plain radiographs. Three complications (33.3%) comprising two periprosthetic fractures and one ulnar neuropathy were observed. Conclusions: Primary TER for treatment of complex distal humerus fractures in elderly patients yielded satisfactory short-term outcomes. However, surgeons should consider the high complication rate after primary TER.