• 융합신호처리학회논문지
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• 제11권3호
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• pp.244-249
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• 2010

차세대 멀티 레벨 셀 플래시 메모리들을 위해 복잡도가 낮은 에러 정정 코드 구현에 대한 요구가 커지고 있다. 일반적으로 부 표현 (sub-expression) 들을 공유하는 것은 복잡도와 칩 면적을 줄이기 위한 효과적인 방법이다. 본 논문에서는 직렬 선형 귀환 쉬프트 레지스터 구조를 기반으로 부 표현들을 이용한 저 복잡도 m-비트 병렬 BCH 인코더 구현 방법을 제안한다. 또한, 부 표현들을 탐색하기 위한 일반화된 방법을 제시한다. 부 표현들은 패리티 생성을 위해 사용하는 행렬(생성 행렬, generator matrix)의 부 행렬 (sub-matrix)과 다른 변수들의 합과의 행렬 연산에 의해 표현된다. 부 표현들의 수는 개로 한정되며, 탐색된 부 표현들은 다른 병렬 BCH 인코더 구현을 위해 공유되어질 수 있다. 본 논문은 구현 과정에서 다수의 팬 아웃에 의해 발생하는 문제점(지연)의 해결이 아닌 복잡도(로직 사이즈) 감소에 그 목적이 있다.

• 한국자동차공학회논문집
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• 제16권6호
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• pp.109-114
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• 2008

An improvement of vehicle fuel economy is one of the most important topic in automotive engineering. Lots of engineers make efforts to achieve 1% of fuel economy improvement. Engine friction is an important factor influencing vehicle fuel economy. This paper focuses on effect of engine friction on vehicle fuel economy during warm-up. A computer simulation is one of the powerful tools in automotive engineering field. Recently Simulation is attempting to virtual experiment not using expensive instruments. It is possible to presuppose fuel economy by changing the characteristic of accessories using CRUISE(vehicle simulation software). In this paper, fuel consumption at each part of the vehicle is analyzed by both of experiment and simulation. The results of fuel economy analysis on experiment substitute for Cruise to calculate fuel economy. The simulation data such as engine speed, brake torque, shift pattern, vehicle speed, fuel consumption level is well correlated to experiment data. In this paper, the change of warm-up time, faster or slower, through simulation is performed. As a result of the fast warm-up, fuel economy is improved up to 1.7%.

• 해양환경안전학회지
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• 제21권6호
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• pp.721-728
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• 2015

행정의 패러다임 변화로 경찰행정도 민간부분과 마찬가지로 고객중심 민원서비스제도의 개선을 위하여 노력하고 있으며 이로 인하여 서비스제공자인 경찰공무원도 부정적인 요소인 감정노동이 발생하고 있다. 이 연구는 해양경찰의 감정노동의 정도를 파악하고 감정노동이 직무소진에 어떠한 영향을 미치는가를 검증하고자 한다. 연구결과는 해양경찰공무원은 공공부분에 종사하는 다른 공무원과 동일하게 감정노동을 경험하고 있는 것으로 조사되었으며, 감정노동이 직무소진에 영향을 미치는 것으로 조사되었다. 즉 해양경찰공무원이 지각하는 감정적 부조화가 고갈에 정(+)의 영향을 미치며, 또한 감정적 부조화는 냉소에 정(+)의 영향을 미치고, 감정표현의 주의정도는 직업효능감 저하에 부(-)적 영향을 미치는 것으로 나타났다. 그러므로 감정노동이 방치된다면 소진에 영향을 미쳐 조직에 부정적인 영향으로 성과달성에 중대한 장애요인이 될 수 있으며, 또한 개인의 신체적, 정신적으로 심각한 문제를 야기할 수 있으므로 이를 예방하기 위한 정책의 시행이 필요하다.

• Archives of Pharmacal Research
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• 제27권5호
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• pp.524-530
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• 2004

Epilepsy or the occurrence of spontaneous recurrent epileptiform discharges (SREDs, seizures) is one of the most common neurological disorders. Shift in the balance of brain between excitatory and inhibitory functions due to different types of structural or functional alterations may cause epileptiform discharges. N-Methyl-D-aspartate (NMDA) receptor dysfunctions have been implicated in modulating seizure activities. Seizures and epilepsy are clearly dependent on elevated intracellular calcium concentration ([C $a^{2+}$]$_{i}$ ) by NMDA receptor activation and can be prevented by NMDA antagonists. This perturbed [C $a^{2+}$]$_{i}$ levels is forerunner of neuronal death. However, therapeutic tools of elevated [C $a^{2+}$]$_{i}$ level during status epilepticus (SE) and SREDs have not been discovered yet. Our previous study showed fast inhibition of ginseng total saponins and ginsenoside R $g_3$ on NMDA receptor-mediated [C $a^{2+}$]$_{i}$ in cultured hippocampal neurons. We, therefore, examined the direct modulation of ginseng on hippocampal neuronal culture model of epilepsy using fura-2-based digital $Ca^{2+}$ imaging and neuronal viability assays. We found that ginseng total saponins and ginsenoside R $g_3$ inhibited $Mg^{2+}$ free-induced increase of [C $a^{2+}$]$_{i}$ and spontaneous [C $a^{2+}$]$_{i}$ oscillations in cultured rat hippocampal neurons. These results suggest that ginseng may playa neuroprotective role in perturbed homeostasis of [C $a^{2+}$]$_{i}$ and neuronal cell death via the inhibition of NMDA receptor-induced SE or SREDs.d SE or SREDs..

• 대한화학회지
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• 제37권8호
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• pp.735-743
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• 1993

Cofacial bis-cobalt tetraphenylporphyrin(Co-TPP) 유도체 화합물들이 수식된 유리질 탄소 전극과 carbon microelectrode을 작업 전극으로 사용하여 여러가지 pH 용액에서 순환 전압전류법 및 시간 전류법에 의해 산소의 환원반응을 조사하였다. 산성용액에서 monomer인 cobalt tetraphenylporphyrin 화합물이 수식된 전극에서 산소의 환원반응경로는 중간 생성물인 H$_2$O$_2$로 가는 2전자 반응으로, dimer인 cofacial bis-cobalt tetraphenylporphyrin 유도체 화합물들이 수식된 전극에서는 최종 생성물인 H$_2$O로 가는 4전자 반응으로 진행되었다. 이와 같은 산소의 환원반응은 전체적으로 비가역적이며 확산지배적인 반응으로 주어졌다. pH 변화에 따른 산소의 환원전위는 pH 13에서 pH 4 까지는 직선관계가 성립하였으나 강한 산성용액에서는 이들 관계가 성립하지 않았다. 산성용액에서 산소의 환원전위는 알몸 유리질 탄소전극에서 보다 monomer Co-TPP 화합물이 수식된 유리질 탄소전극에서는 400 mV만큼, dimer Co-TPP 화합물이 수식된 전극에서는 750 mV 만큼 더 양전위 방향으로 이동되었다.

• 대기
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• 제27권2호
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• pp.177-188
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• 2017

The development mechanisms of an unusual heavy snowfall event, which occurred in the coast of Jeju Island on 23 January 2016 were investigated through a thermodynamic approach. The formation of heavy snowfall was attributed to the enhanced thermal convection in two ways. First, the convection was enhanced by the air-sea temperature difference between the cold air advection in low-troposphere associated with the strengthening of the Siberian High and abnormal warm sea surface temperature, which is $1{\sim}2^{\circ}C$ higher than normal year over the Yellow Sea (YS). Second, the convective instability was increased by the vertical temperature gradient between the 7 days-sustained cold air advection in low-troposphere and the abrupt cold air intrusion in mid-troposphere induced by the southward shift of a cold cut-off vortex ($-45^{\circ}C$) at the formation stage. Compared to the twelve hours prior to the formation, the low-level moisture increased by 5% through the moisture supply from the YS, and the air-sea temperature difference increased from $18.5^{\circ}C$ to $28.5^{\circ}C$. Furthermore, the upward sensible (latent) heat flux increased 1.5 (1.2) times over the YS before the twelve hours prior to the formation. Thereafter, the sustained moisture supply and upward turbulent heat flux helped to maintain the snowstorm.

• 대한의용생체공학회:의공학회지
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• 제20권3호
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• pp.299-305
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• 1999

본 연구에서는 잡음이 포함된 심전도 신호로부터 진단 파라미터 추출을 위한 대표 비트 설정에 관한 알고리즘들을 비교 분석하였다. 사용된 알고리즘들은 중앙 집중치를 계산하기 위하여 사용되는 방법들로써 산술평균, 중앙값 , 최빈값 ; 절사 평균을 이용하였다. 첨가된 잡음들은 심전도 신호에서 자주 발생되는 근전도 잡음, 60Hz 전원잡음, 급작성 기저선 변동 , 호흡에 의한 기저선 변동을 제한시켰고 각각의 잡음들이 첨가되었을 때의 신호대 잡음비를 계산하였다. 연구 결과, 신호 평균화 방법은 근전도 잡음이 포함되었을 때 신호 대 잡음비가 가장 높았으며, 중앙값 , 최빈값 , 절사 평균을 이용하는 방법들은 급작성 기저선 변동과 같이 입력 신호에 극단값이 존재할 때 높은 신호 대 잡음비를 가지고 있다. 특히 호흡에 의한 기저선 변동 잡음이 포함된 경우에는 절사 평균을 이용하여 설정된 대표 비트의 ST 레벨 변화가 0 V 로써 가장 효율적이었다.

• The Korean Journal of Physiology
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• 제20권2호
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• pp.165-174
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• 1986

The voltage clamp studies were undertaken to elucidate the properties of the slow inward current, $i_{si}$, in the small preparations of the rabbit sinoatrial node. The slow inward current, $i_{si}$, which is known to be responsible for the late one-third of pacemaker potential and whole range of upstroke phase of action potential was analysed with the effects of isoprenaline, cobalt, ouabain and higenamine. The results obtained are as follows; 1) Voltage of SA node preparation was held at zero current level, usually-40mV and the slow inward current, $i_{si}$, was activated by depolarizing clamp pulses. Peak values of $i_{si}$, in steady state were at $-10{\pm}0mV$ in most preparations. 2) Isoprenaline, ${\beta}-agonist$ increased $i_{si}$ and no shift was noticed in voltage-dependency. 3) Cobalt ion in the concentration of 1 mM abolished is, in entire range of membrane potential and the difference of two current levels before and after $Co^{2+}$ treatment could be considered as pure $i_{si}$ magnitude. 4) In the therapeutic concentration of ouabain $(5{\times}10^{-8}M)$ slightly increased is, and reduced the time to reach the peak value. 5) Higenamine $(10^{-6}M)$ changed the configurations of action potential (i. e. rapid upstroke phase and notch in the spike) and increase spontaneous rate. It also increased is, and the effect of higenamine was blocked ${\beta}-blocker$, propranolol $(10^{-6}M)$.

• The Journal of Asian Finance, Economics and Business
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• 제7권11호
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• pp.1049-1057
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• 2020

The shift from elite education to mass education in Vietnam has met the demand for education for everybody as well as for quality human resource talent for an emerging nation. Under the resource constraint, understanding the quality dimensions of education and its priority level is important for effective and efficient policies. This study was carried out using both qualitative and quantitative methodologies to develop quality criteria and a ranking model. Two rounds of in-depth interviews were conducted with fifteen experts in the field, who were rectors, employers, and recruitment specialists to develop the quality framework applied in Vietnamese universities under total quality management (TQM), starting from the input of the senior secondary school leavers, through a teaching process to the output. The first round of interviews were unstructured questionnaires designed to explore the main factors in quality assessment model. The second round affirmed the experts' agreement on the assessment model. Then, fuzzy logic was applied to rank eight criteria in the quality assessment model into priority order: cost, teaching and administrative staff, leadership, curriculum, student-related factors, internationalization, admissions, and campus. The results are critical for identifying the necessary actions to enhance the education quality and to further research on the optimal quality model.

• Archives of Pharmacal Research
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• 제11권1호
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• pp.33-40
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• 1988

Two new nitro analogs of tranylcypromine, (E)-2-(p-nitrophenyl)cyclopropylamine ((E)-p-NTCP) and (E)-2-(m-nitrophenyl)cyclopropylamine ((E)-m-NTCP) were synthesized in order to examine the effect of aromatic nitro substitution on the MAO-inhibitory activity of 2-phenylcyclopropylamines. The compounds were obtained by treating t-butyl (E)-2-(p-nitrophenyl) cyclopropanecarbamate and t-butyl (E)-2-(m-nitrophenyl)cyclopropanecarbamate with p-toluenesulfonic acid in $CH_3$CN. Inhibitions of rat brain mitochondrial MAO-A and B by the compounds were examined using serotonin and benzylamine as the substrate at both in vitro and ex vivo levels. It was found from in vitro measurements that (E)-p-NTCP at $6.0{\times}10^{-5}M$ elicited merely 22.5% inhibition against MAO-B without any effect on MAO-A. In contrast, (E)-m-NTCP showed fair degrees of inhibitions of MAO-A and B with $IC_{50}$ values, $2.5{\times}10^{-7}M\;and\;1.4{\times}10^{-6}M$, respectively. It was also noted from (E)-m-NTCP that m-nitro substitution caused a shift of selectivity of the inhibition toward MAO-A. According to ex vivo measurements at 1.5, 3, 6, and 12 hr following the administration of a dose of 0.015 mmol/kg, i.p. to the rats, the inhibition percents of MAO-A by (E)-m-NTCP were 58.6, 63.7 63.6, and 46.6%, slightly lower than those observed by tranylcypromine. Whereas, (E)-m-NTCP at the same dose level did not show significant inhibitions against both MAO-A and MAO-B. Possible reasons for the difference in potencies between (E)-m-NTCP and (E)-p-NTCP were sought in relation to differing electron withdrawing effects of m- and p-substituents which will influence electron density of the side chain amino functions and the partitions.