• International journal of advanced smart convergence
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• 제9권3호
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• pp.49-58
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• 2020

Non-orthogonal multiple access (NOMA) has been recognized as a significant technology in the fifth generation (5G) and beyond mobile communication, which encompasses the advanced smart convergence of the artificial intelligence (AI) and the internet of things (IoT). In NOMA, since the channel resources are shared by many users, it is essential to establish the user fairness. Such fairness is achieved by the power allocation among the users, and in turn, the less power is allocated to the stronger channel users. Especially, the first and second strong channel users have to share the extremely small amount of power. In this paper, we consider the power optimization for the two users with the small power. First, the closed-form expression for the power allocation is derived and then the results are validated by the numerical results. Furthermore, with the derived analytical expression, for the various channel environments, the optimal power allocation is investigated and the impact of the channel gain difference on the power allocation is analyzed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.495-500
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• 2001

The dynamic behavior of high speed train is very important because it should be safe and is satisfied with the ride comfort of passengers. The railway is composed of many suspension components-1st springs, 1st dampers, 2nd springs, 2nd dampers etc- that have an influence on the dynamic characteristics of high speed train. Also, the wheel/rail shapes, the track condition and geometry and many environmental factors-rain, snow, wind etc-are affected the dynamic behavior of high speed train. This paper is reviewed the effect of wind(gust) on the dynamic behavior of high speed train. Vampire program is used for this simulation. The result of simulation shows that high speed train should not be operated when the gust speed is beyond 34.5m/sec.

• 한국정보통신학회논문지
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• 제5권4호
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• pp.716-722
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• 2001

본 논문은 3세대 및 그 이상의 무선망에 대한 기본적인 망의 구조를 IP를 바탕으로한 무선망으로 정의하고 이때 무선 접속망에서의 폭주제어 방법을 제안한다. 기본적으로 제안하는 방법은 ECN(Explicit Congestion Notification)을 바탕으로 하나 무선망과 IP망의 Broadcasting에서의 장점을 이용하여 ECN Broadcasting을 무선 서브망에서 수행하도록 하여 미래의 무선망에서의 이동성 지원으로 인한 폭주제어에 있어서 효율성을 갖도록 하였다.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.283-290
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• 2021

Recently, correlated superposition coding (CSC) has been proposed to implement non-orthogonal multiple access (NOMA) without successive interference cancellation (SIC), without loss of spectral efficiency, in contrast to conventional independent superposition coding (ISC). However, correlation between signals has reduced the average total allocated power, which results in degraded performance. Thus, in order to avoid the reduction of the average total allocated power owing to correlation between signals, this paper proposes a cross-correlated quadrature amplitude modulation (QAM) NOMA scheme under Rayleigh fading channel surroundings. First, we design the cross-correlated QAM NOMA scheme. Then, simulations demonstrate that for the weaker channel gain's user, the symbol error rate (SER) performance of the proposed cross-correlated QAM NOMA improves largely, whereas for the stronger channel gain's user, the SER performance of the proposed cross-correlated QAM CSM NOMA degrades little, compared to that of the conventional QAM NOMA.

• International Journal of Advanced Culture Technology
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• 제9권4호
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• pp.307-314
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• 2021

Recently, positively asymmetric binary pulse amplitude modulation (2PAM) has been proposed to improve the bit error rate (BER) performance of the weak channel gain user, with a tolerable BER loss of the strong channel gain user, for non-orthogonal multiple access (NOMA). However, the BER loss of the stronger channel gain user is inevitable in such positively asymmetric 2PAM NOMA scheme. Thus, we propose the negatively asymmetric 2PAM NOMA scheme. First, we derive closed-form expressions for the BERs of the negatively asymmetric 2PAM NOMA. Then, simulations demonstrate that for the stronger channel gain user, the BER of the proposed negatively asymmetric 2PAM NOMA improves, compared to that of the conventional positively asymmetric 2PAM NOMA. Moreover, we also show that for the weaker channel gain user, the BER of the proposed negatively asymmetric 2PAM NOMA is comparable to that of the conventional positively asymmetric 2PAM NOMA, over the power allocation range less than about 10 %.

• Journal of Nutrition and Health
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• 제44권4호
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• pp.338-343
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• 2011

This study assessed the current EAR, RDA, and AMDR for protein, which were set in 2005 and revised in 2010 as the DRIs for Koreans. A classical approach to establish the EAR for protein has been the nitrogen balance method. This method has practical limitations and problems in statistical analysis by giving over estimations of nitrogen balance. Thus, the present EAR for protein might be lower than the true requirement. Recent reevaluations of nitrogen balance studies by bilinear regression analysis and the IAAO method have indicated that the EAR of 0.66 g/kg bw/d should be increased by 39% to give 0.92 g/kg bw/d. The AMDR for protein in the Korean DRIs was set at 7-10%, which covers almost the entire population's protein intake. Since the 5th percentile of Korean protein intake is close to 10% of energy and due to the beneficial effects of protein beyond the maintenance of nitrogen equilibrium, the lower range of 7% needs to be increased up to 10%. For practical meal arrangement, 15% of energy as protein, which is close to the average protein intake of Koreans, seems to be proper, although the value is almost two times the EAR.

• 한국비블리아학회지
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• 제23권1호
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• pp.5-26
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• 2012

FRSAD과 온톨로지 모형간의 연계는 어떠한 정보구현시스템이나 특정 상황에서도 독립적인 상위 계층의 지식구조를 제안하고, 의미 연결, 지식구조, 주제접근, 상호운용성 등을 확보하기 위한 노력이다. FRSAD 모형을 현실적인 정보환경에 적용하고, 도서관 안팎 어디서나 자유롭게 정보를 확인하고 공유하기 위해서는 지식표현 인코딩 체계가 필요하다. 본 연구에서는 웹 온톨로지 언어인 OWL를 사용하여 FRSAD 모형을 온톨로지 구조로 표현하였으며, 이를 확인하기 위해 Prot$\acute{e}$g$\acute{e}$를 사용하여 FRSAD 온톨로지 모형을 시범적으로 구축하였다.

• Archives of Pharmacal Research
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• 제14권4호
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• pp.330-335
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• 1991

The effects of physostigmine and neostigmine on the parathin induced toxicity were examined in adult female rats. Physostigmine $(100\;{\mu}g/kg,\;ip)$ or neostigmine $(200\;{\mu}g/kg,\;ip)$ inhibited acetylcholinesterase (AChE) and cholinesterase (ChE) activities in blood, brain and lung when the enzyme activity was measured 30 min after the treatment. At the doses of two carbamates equipotent on brain AChE, neostigmine showed greater inhibition on peripheral AChE/ChE. The enzyme activity returned to normal in 120 min following the carbamates except in the lung of rats treated with neostigmine. Carbamates administered 30 min prior to parathion (2 mg/kg) antagonized the inhibition of AChE/ChE by parathion when the enzyme activity was measured 2 hr following parathion. Neostigmine showed greater protective effect on peripheral AChE/ChE. The effect of either carbamate on AChE/ChE was not significant 2 hr beyond the parathion treatment. Carbamates decreased the mortality of rats challenged with a lethal dose of parathion (4 mg/kg, ip) either when treated alone or in combination with atropine (10 mg/kg, ip). Lethal action of paraoxon (1.5 mg/ks ip), the active metabolite of parathion was also decreased by the carbamate treatment indicating that the protection was not mediated by competitive inhibition of metabolic conversion of parathion to paraoxon. The results suggest that carbamylation of the active sites may not be the sole underlying mechanism of protection provided by the carbamates.

• 한국가금학회지
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• 제27권3호
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• pp.189-195
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• 2000

Microbiological and sensory evaluations of chicken wings treated with acetic acid and trisodium phosphate(TSP) during retail(1${\pm}$2$^{\circ}C$) and refrigerated storage(4$^{\circ}C$). Chicken wings(average weight of 15${\pm}$2g per leg) were treated with 0.5∼2% aerobic plate counts(APC) on the surface of chicken wings for storage of 16 days at 4$^{\circ}C$. During storage of 12 days at retail store(1${\pm}$2$^{\circ}C$), the treating chicken wings with 7.5∼10% TSP solutions for 10 min showed significantly inhibitory effect in preventing the growth of aerobic microbes. For odor and appearance scores, chicken wings treated with 0.5∼2% acetic solutions resembled untreated wings for storage of 16 days at 4$^{\circ}C$. However, both odor and appearance scores of chicken wings treated with 2.5∼10% TSP solutions were similar to those of untreated wings for storage of 4 days, and a higher in the storage of beyond 8 to 12 days at retail store.

• 한국염색가공학회지
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• 제24권4호
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• pp.253-259
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• 2012

In this work, the natural indigo production process from Polygonum tinctorium was balanced based on the traditional Niram method in Korea. A standard procedure was determined considering the conditions of indican extraction from plant material, the amount of alkali for precipitation, storage of extract, etc. The effect of experimental conditions on the yield of crude dye was investigated. The contents of indigo and indirubin of the crude dyes were analyzed by HPLC. Increase of the amount of crude dye was observed within 1-2.5 days of extraction time. Longer extraction beyond 2.5 days resulted in a slight decrease in the amount of crude dye. There was no consistency in terms of indigo content depending on extraction pH. We found that the storage of extract or harvested plants affected adversely to dye yield and dye quality. Based on the lab scale extraction, large scale extraction was performed for 2-2.5 days in water and 2.0-2.5 g/L of $Ca(OH)_2$ was applied for precipitation of indigo dye. We obtained natural indigo dye containing about 15% of pure indigo in scale-up production using whole plant except root.