• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.163.1-163.1
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• 2010

2030년까지 신재생에너지발전 비중을 11%로 높이겠다는 정책목표 달성을 위한 정부의 지원방안이 현행 발전차액지원제도(FIT)에서 2012년부터는 신재생에너지의무할당제(RPS)로 전환된다. 전원별로 정해진 발전량에 대해 정부가 일정한 가격으로 구매해주는 현행 제도 하에서 신재생에너지발전사업자는 중장기 가격을 보장받음으로써 수익성을 초기에 확정할 수 있는 장점이 있는 반면 정부 입장에서는 보급이 확대될수록 막대한 재정부담이 발생하고 경쟁을 통해 생산 비용을 낮추기 위한 유인이 부족한 단점이 있다. 이러한 단점을 보완하기 위해 도입되는 의무할당제는 일정 설비규모 이상의 발전사업자에게 신재생에너지발전 의무량을 부과하고 의무대상자가 의무이행의 수단으로 공급인증서(REC)를 발급받거나 구매하여 의무를 이행토록 하는 제도로서 공급인증서 가격 결정을 시장기능에 맡김으로써 신재생에너지 사업자간 경쟁을 촉진시켜 생산비용을 절감하고 정부의 재정부담을 완화하는 장점이 있는 반면 신재생에너지발전사업자 입장에서는 수익성 분석이 복잡해지고 리스크가 증가하는 문제점이 있다. 특히 발전용 연료전지를 활용한 발전사업의 경우 다른 신재생에너지원과 달리 설비투자비용(CAPEX) 외에 가스요금 및 핵심부품의 주기적인 교체 등을 위한 운영비용(OPEX)의 비중이 작지 않기 때문에 더욱 정밀한 분석이 필요하다. 본 연구에서는 신재생에너지발전사업자 입장에서 비용과 편익에 영향을 미치는 각 요소와 그 영향을 파악함으로써 발전용 연료전지의 경제성 분석을 시도해 보았다.

• Journal of Broadcast Engineering
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• v.15 no.6
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• pp.731-741
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• 2010

In this paper, we propose the methodology of prediction of field strength for a digital television (DTV) receiver by virtue of Recommendation ITU-R P.1546. The curves shown in this recommendation represent the point-to area field strength for 1.0 kW effective radiated power in the 30 MHz ~ 3000 MHz. Based upon the procedures described in this Recommendation, computation results are presented here from the derived formulation of field strength for DTV receiver. To show the validity of this method, some results are compared with the analysis by Okumura-Hata model and it was shown that the error of field strength is in the range of 6.9 ~ 11.5 %. The presented method provides not only the predicted values of field strength for DTV receiving area to check the quality of transmitted signal, but also an appropriate site selection for obtaining good propagation environment. In addition, it can be directly used for analyzing the protection ratio or separated distance for frequency sharing in the same band.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.753-756
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• 2008

HPFRCC (High-Performance Fiber Reinforced Cementitious Composites), which is relatively more ductile and has the characteristic of high toughness with high fiber volume fractions, can be used in structures subjected to extreme loads and exposed to durability problems. In the case of using PVA(polyvinyl alcohol) fibers, it is noted by former studies that around 2% fiber volume fractions contributes to the most effective performance at HPFRCC. In this study, therefore, compressive and flexural tests were implemented to evaluate the compressive and flexural capacities of HPFRCC while the total fiber volume fractions was fixed at 2% and two different PVA fibers were used with variable fiber volume fractions to control the micro-crack and macro-crack with short and long fibers, respectively. Moreover, specimens reinforced with steel and PVA fiber simultaneously were also tested to estimate their behavior and finally find out the optimized mixture. In the result of these experiments, the specimen consists of 1.6% short fibers (REC 15) and 0.4% long fiber (RF4000) outperformed other specimens. When a little steel fibers added to the mixture with 2% PVA fibers, the flexural capacity was increased, however, when high steel fiber volume fractions applied, the flexural capacity was decreased.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.2
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• pp.161-167
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• 2008

This paper describes the overview of spectrum requirement estimation recommended in ITU-R Rec. M.1390 and [IMT.METH] and its difference for the IMT mobile service, and a (IMT.METH) methodology is applied to the spectrum estimation of the recent IMT service. The traffic model and traffic calculation algorithm is briefly described for the carried traffic which is determined in terms of the offered traffic, system rapacity, and the criteria of quality of service. And the spectrum requirement demand which is required from year 2010 to year 2015 is calculated as an example for the IMT service which is recently operated and deployed in the current Korean market after obtaining the reasonable market data and the ITU market prediction data.

• BMB Reports
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• v.38 no.5
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• pp.545-549
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• 2005

Acidithiobacillus ferrooxidans is one of the most important bacterium used in bioleaching, and can utilize $Fe^{2+}$ or sulphide as energy source. Growth curves for Acidithiobacillus ferrooxidans under phosphate starvation and normal condition have been tested, showing lag, logarithmic, stationary and aging phases as seen in other bacteria. The logarithmic phases were from 10 to 32 hours for Acidithiobacillus ferrooxidans cultivated with normal cultivating condition and from 20 to 60 hrs for Acidithiobacillus ferrooxidans cultivated phosphate starvation. Differences of protein patterns of Acidithiobacillus ferrooxidans growing in case of normal or phosphate starvation were separately investigated after cultivation at $30^{\circ}C$ by the analysis of two-dimensional gel electrophoresis (2-DE), matrix-assisted laser desorption/ionization (MALDI)-Mass spectrometry. There were total 6 protein spots identified, which were Recombination protein recA, RNA helicase, AP2 domain-containing transcription factor, NADH dehydrogenase I chain D, Hyothetical protein PF1669, and Transaldolase STY3758. From the 6 identified protein spots, 3 proteins were found to be decreased in expression at the cultivating condition of phosphate starvation, while another three upregulated.

• Archives of Reconstructive Microsurgery
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• v.6 no.1
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• pp.1-8
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• 1997

Recently prostaglandin $E_1(PGE_1)$ has been shown to ensure flap survival by producing vasodilation of the peripheral vessels and platelet disaggreation. However, direct observation and detailed quantitative studies of the effects of $PGE_1$ on the cutaneous microcirculation have not been reported. In the present study, we investigated cutaneous microcirculatory changes in the rabbit ear chamber(REC) with an intravital microscope following intravenous administration of $PGE_1$. The results obtained in this study indicate that $PGE_1$ administered intravenously at a rate of 200ng/kg/min might act directly on the vessels and cause dilatation of metarterioles and capillaries without affecting vasomotion and systemic blood pressure. Clinically in order to evaluate the effect of an intravenous administration of $PGE_1$ on the cutaneous microcirculation, cutaneous blood flow, skin temperature and transcutaneous $Po_2$ in the pedicle or free flap of operated patients were evaluated by the combination of several measurements following the administration of $PGE_1$. The present study suggests that improvement of cutaneous microcirculation by $PGE_1$ may enhance the survival rate of flap or replantation. Both vessel arterial ischemia and venous congestion are main factors of tissue necrosis in the flap surgery. Vasodilatory or antithrombotic agents have been used in salvage of flap necrosis. However, the therapeutic effects of those drugs are still not well elucidated. Recently prostaglandin $E_1(PGE_1)$ has been shown to ensure flap survival by producing vasodilatation of the peripheral vessels and platelet disaggregation[1-3]. Emerson and sykes[4] have obtained significant improvement in the flap survival in the rat using $PGI_2$. Suzuki et al.[5] have reported prolonged flap survival length by using $PGE_1$ in the rabbit and concluded that $PGE_1$ improved the microcircuration in the flap. However, direct observation and detailed quantitative studies of the effects of $PGE_1$ on the cutaneous microcirculation have not been reported. In the present study, we investigated microcirculatory changes in the rabbit ear chamber[6,7] with an intravital microscope following intravenous administration of $PGE_1$.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.2 no.2
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• pp.23-47
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• 2007

Since 1998, Korean economy has damaged financial structural coordination from business firms to financial institutions. The monetary circumstances, the faithless management in financial institution, caused an usiness shrinkage. Specially, the monetary circumstances come by every year from large to small. This dissertation examines the recognition & experience of institution employee to the monetary circumstances that underlie the announcement effects. The sample of this study consists of 201 survey which have 1st and 2nd financial institution from Gyeungnam to Seoul. To examine and identify factors that the Recognition & Experience of the Monetary Circumstances this study uses t-test, ANOVA, multiple regression. The variables SEX, AFF, FRA show expected signs and are statistically significant. The variables MAR, SCH, PER, POS, LEN and REC were turned out to be insignificant. The above results suggest that institution employee, which have male, take part lending in affairs and uneasy home status, have more recognize to the financial circumstances.

• Journal of Yeungnam Medical Science
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• v.28 no.1
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• pp.60-69
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• 2011

Due to its efficacy and tolerability, low dose oral methotrexate (MTX) therapy has been widely used for treatment of rheumatoid arthritis (RA). However, it can rarely cause serious, life-threatening hematologic toxicities, such as pancytopenia. We report here on two patients with chronic kidney disease (CKD), who developed severe pancytopenia after 5 years (cumulative dose 1,240 mg) and 4 years (cumulative dose 1,320 mg) of low dose MTX therapy for treatment of RA, respectively. Both patients presented with renal insufficiency, hypoalbuminemia, concurrent use of nonsteroidal anti-inflammatory drugs, and elevated mean corpuscular volume of red blood cells (RECs), all of which are known as risk factors of MTX-induced pancytopenia. Despite receiving treatment, which included REC and platelet transfusions, antibiotic therapy, granulocyte colony stimulating factor, and leucovorin rescue, one patient died of sepsis. Based on our case study, prompt investigation of risk factors associated with MTX toxicity is required for all patients receiving MTX therapy. MTX treatment, even at a low dose, should be discontinued in patients with advanced CKD.

• Journal of Advanced Navigation Technology
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• v.18 no.6
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• pp.541-545
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• 2014

Rec. ITU-R M.1842-1 is international recommendation for VHF band communication guideline in maritime mobile service RR Appendix 18 channels. In this paper, we simulate 28.8 kbps VHF ${\pi}$/4-DQPSK digital baseband modem compatible with the recommendation, then it is designed and implemented with FPGA. Cazac sequence is used as a preamble since packet format is not defined untill now in the recommendation. Baseband modem is designed by VHDL language and implemented on NEXYS4 development platform having Atrix7 FPGA chip from Xilinx. For wireless communication test of total prototype system, ADC/DAC board is implemented and EV9730 RF module is utilized. From the experimental results, implemented FPGA modem shows spectral bandwidth of 25 kHz and successful data exchanges between tx and rx communication platform.

• Journal of Korean Medicine Rehabilitation
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• v.21 no.4
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• pp.257-267
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• 2011

Objectives: The purpose of this study is to evaluate the effect of the burning acupuncture therapy and exercise therapy on the internal derangement of knee with patella tendon and posterior cruciate ligament injury. Methods: Burning acupuncture therapy was administered three times and exercise therapy was administered during 4 weeks. The improvement of clinical symptom was evaluated by VAS(visual analogue scale) and KOOS(knee injury and osteoarthritis outcome score). Results: After treatment, the patient's VAS score was reduced to 0 pant. The KOOS score of pain, symptom, ADL, sport/rec, QOL(quality of life) improved from 28 to 75, from 36 to 71, from 22 to 65, from 0 to 15, from 25 to 38 respectively. Conclusions: Burning acupuncture therapy and exercise therapy fer internal derangement of knee with patella tendon and posterior cruciate ligament injury was effective. Although this case presented valuable result, further research is encouraged to confirm the effectiveness of this treatment with large number of patient.