• Bulletin of the Korean Chemical Society
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• 제7권5호
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• pp.367-371
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• 1986

Dynamic and equilibrium properties of n-alkane chains immersed in solvent molecules have been investigated by a molecular dynamics method. The n-alkane chain is assumed to be a chain of elements (CH$_2$) interconnected by bonds having a fixed bond length and bond angle, but each bond of the chain is allowed to execute hindered internal rotation. We studied the effect of the number of the chain elements (N$_c$ = 10, 15 and 20) on the equilibrium properties of the system, e.g., the pair correlation functions between a chain element and solvent molecules, g$_{cs}$(r), and between the chain elements, g$_{cc}$(r), and the configurational properties such as the mean-square end-to-end distance < R$^2$ >, the mean-square radius of gyration < S$^2$ >, and the eigenvalues of the moment-of-inertia tensor < S$_i^2$ > / < S$^2$ > (i = 1, 2 and 3). We also studied the dynamic properties of the system, e.g., the autocorrelation function C(A;t) where A = R$^2$(t), = S$^2$(t), or = ${\vec{V}}(t)({\vec{V}}$ = velocity of the center of mass), and the diffusion coefficient D. The g$_{cs}$(r)'s are almost equal irrespective of the change of Nc while g$_{cc}$(r) becomes larger as N$_c$ increases; The MD computed configurational properties < R$^2$2 > and < S$^2$ > were found to be a little different from the values calculated from the statistical equations of < R$^2$ > and < S$^2$ >, it may be due to the fact that our model for the MD simulations includes a long-range volume effect. From the < S$_i^2$ > / < S$^2$ >, it is found that the chain molecule has a nearly spherical shape irrespective of the variation of N$_c$. For the dynamic properties we found that the C(R$^2$;t) and C(S$^2$;t) of lower N$_c$ decay faster than those of higher N$_c$, while the C($\vec V$;t) of the center of mass in the chain is weakly dependent on the N$_c$. The center of mass diffusion coefficient D$_c$ decreases as N$_c$ increases while the end point diffusion coefficient D$_e$ is nearly equal irrespective of the change of N$_c$.

• 한국균학회지
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• 제24권3호통권78호
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• pp.206-213
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• 1996

Talaromyces luteus 6112 균주에 돌연변이원 N-methyl-N'-nitro-N-nitrosoguanidine을 처리하여 고온성 돌연변이주인 T. luteus 2004를 선별하였다. T. luteus 2004 균주는 고온성 섬유소 분해 효소인 carboxymethylcellulase(CMCase)와 그 외의 다당류 분해효소인 avicellase, xylanase, ${\beta}-glucosidase$ 등을 생성하였다. 고온성 섬유소 분해효소의 생성은 3% carboxymethylcellulose(CMC) 최소배지에서 가장 높게 유도되었으므로 CMC가 CMCase 생성의 유도물질임을 알 수 있었다. 고온성 섬유소분해효소의 생성에 있어서 포도당과 D-cellobiose는 CMCase 생성에 catabolite repressor로 작용함을 보여 주었다. T. luteus 2004의 섬유소 분해효소의 효소학적 특성은 $70^{\circ}C$, pH 4에서 최고의 활성을 보여주는 고온성 효소이므로 대체에너지 개발에 활용 가능한 균주로 사료된다.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제4권1호
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• pp.101-107
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• 2000

In this paper we establish an upper bound for the estimation error variance of a continuous stream with a stationary variogram V which is assumed to be of the r-Holder type (Lipschitzian) on [-d, d]. Functional properties for the mapping ${\xi}(t):=E[(X-X(t))^2]$, $t{\in}[0,d]$, are also given.

• EDISON SW 활용 경진대회 논문집
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• 제2회(2013년)
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• pp.224-227
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• 2013

본 연구에서는 S/D이 n+/n+로 구성된 CNT-MOSFETs, 금속으로 이루어진 SB-CNTFETs와 p+/n+로 구성된 CNT-TFETs에 대한 각각의 $I_d-V_g$ 특성과 포텐셜 프로파일을 확인하였다. 그리고 각 소자의 특성 및 특징을 연구하고, 이 중에서 BTB에 가장 큰 영향을 받는 CNT-TFETs의 특성을 $V_{DS}$, 분자 비대칭성과 $T_{ox}$에 따른 특성 변화를 연구하였다. 그 결과 예상과 다르게 오히려 작은 $V_{DS}$와 큰 $E_g$을 가질 때, 향상된 SS를 가진다는 것을 확인 할 수 있었다. 특히, (7,0) CNT-TFETs에서 비록 $I_d$는 작지만, SS를 57mV/dec까지 개선할 수 있었다. 또한, $T_{ox}$를 얇게 하면, 비록 60 mV/dec 이하의 결과는 보여주지 못했지만, SS와 Ion 모두 개선할 수 있음을 확인할 수 있었다.

• 한국전자통신학회논문지
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• 제7권6호
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• pp.1369-1375
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• 2012

수열이론의 중요한 문제 중 하나는 두 수열사이의 상호 상관관계가 몇 개의 서로 다른 값을 가지며 또한 그 값의 발생횟수이다. 본 논문에서는 주기가 $2^n-1$인 m-수열 u(t)와 그 수열을 d만큼 데시메이션해서 얻은 수열 $u(dt)(0{\leq}t{\leq}2^n-2)$사이의 상호상관관계의 값과 그 값의 발생 횟수를 찾는다. 여기서 n=2m, 2s|m 이고, $d=(2^{2m}+2^{2s+1}-2^{m+s+1}-1)/(2^s-1)$ 이다. 또한 제안된 데시메이션에 의해 생성된 수열이 4-값 상호상관관계를 가짐을 보인다.

• 대한수학회지
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• 제58권3호
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• pp.643-702
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• 2021

Fix ℤ/2 is the prime field of two elements and write 𝒜₂ for the mod 2 Steenrod algebra. Denote by GL_d := GL(d, ℤ/2) the general linear group of rank d over ℤ/2 and by ${\mathfrak{P}}_d$ the polynomial algebra ℤ/2[x₁, x₂, …, x_d] as a connected unstable 𝒜₂-module on d generators of degree one. We study the Peterson "hit problem" of finding the minimal set of 𝒜₂-generators for ${\mathfrak{P}}_d$. Equivalently, we need to determine a basis for the ℤ/2-vector space $$Q{\mathfrak{P}}_d:={\mathbb{Z}}/2{\otimes}_{\mathcal{A}_2}\;{\mathfrak{P}}_d{\sim_=}{\mathfrak{P}}_d/{\mathcal{A}}^+_2{\mathfrak{P}}_d$$ in each degree n ≥ 1. Note that this space is a representation of GL_d over ℤ/2. The problem for d = 5 is not yet completely solved, and unknown in general. In this work, we give an explicit solution to the hit problem of five variables in the generic degree n = r(2^t - 1) + 2^ts with r = d = 5, s = 8 and t an arbitrary non-negative integer. An application of this study to the cases t = 0 and t = 1 shows that the Singer algebraic transfer of rank 5 is an isomorphism in the bidegrees (5, 5 + (13.2⁰ - 5)) and (5, 5 + (13.2¹ - 5)). Moreover, the result when t ≥ 2 was also discussed. Here, the Singer transfer of rank d is a ℤ/2-algebra homomorphism from GL_d-coinvariants of certain subspaces of $Q{\mathfrak{P}}_d$ to the cohomology groups of the Steenrod algebra, $Ext^{d,d+*}_{\mathcal{A}_2}$ (ℤ/2, ℤ/2). It is one of the useful tools for studying these mysterious Ext groups.

• Journal of applied mathematics & informatics
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• 제30권5_6호
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• pp.903-911
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• 2012

Let $\{u(t)\}$ and $\{u(dt)\}$ be two maximal length sequences of period $2^n-1$. The cross-correlation is defined by $C_d({\tau})=\sum{_{t=0}^{2^n-2}}(-1)^{u(t+{\tau})+v(t)$ for ${\tau}=0,1,{\cdots},2^n-2$. In this paper, we propose a new proof for finding the values and the number of occurrences of each value of $C_d({\tau})$ when $d=2^{k-2}(2^k+3)$, where $n=2k$, $k$ is a positive integer.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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• pp.203-206
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• 2000

Since the amplitude of voiced fall off at about -20dB/decade, dynamic range is often compressed prior to spectral analysis so that details at weak, high frequencies may be visible. Preemphasizing the speech, either by differentiating the analog speech s$\sub$a(t) prior to A/D conversion or by differencing the discrete-time s(n)=s$\sub$a(nT), compensating for falloff at high frequencies. The most common form of preemphasis is y(n)=s(n)-As(n-1), where A typically lies between 0.9 and 1.0 and reflects the degree of pre-emphasis. In This paper, we proposed that A is adjusted at each time by measuring the slope of envelope in frequency domain.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2010년도 춘계학술발표논문집 1부
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• pp.253-256
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• 2010

Since the amplitude of voiced fall off at about -20dB/decade, dynamic range is often compressed prior to spectral analysis so that details at weak, high frequencies may be visible. Preemphasizing the speech, either by differentiating the analog speech $s_a$(t) prior to A/D conversion or by differencing the discrete-time s(n)=$s_a$(nT), compensating for falloff at high frequencies. The most common form of preemphasis is y(n)=s(n)-As(n-1), where A typically lies between 0.9 and 1.0 and reflects the degree of pre-emphasis. In this paper, we proposed that A is adjusted at each time by measuring the slope of envelope in frequency domain.

• 한국한의학연구원논문집
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• 제1권1호
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• pp.1-14
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• 1995

The clinical study was carried out on 1737 cases of inpatient and outpatient which have been diagnosed as C.V.A at hospital attached to 8 colleges of oriental medicine in Korea or National Medical Center from January 1st 1994 to December 31st 1994. The results were as follows; 1. In this study, the case of Occlusive C.V.D was 70.1%, Cerebral hemorrhage was 20.5%, Transient ischemic attack (T.I.A) was 5.3%, Subdural hemorrhage was 3.0%, Subarachnoid hemorrhage was 0.8% 2. It was confirmed by C.T (20%), E.K.G. (19%), X-ray (19%), Urinalysis (19%), Hematoscopy (20%). 3. The mean days of hospital treatment was 27.88 days, mean days of ambulation was 70.34 days. The mean days of hospital treatment of Occlusive C.V.D, Cerebral hemorrhage, T.I.A., Subdural hemorrhage, Subarachnoid hemorrhage were 25.79, 39.32, 12.49, 16.23, 23.40 days, respectively. The mean days of ambulation of Occlusive C.V.D, Cerbral hemorrhage, T.I.A., Subdural hemorrhage, Subarachnoid hemorrhage were 74.40, 93.68, 69.10, 29.75, 32.57 days, respectavely. 4. Oriental medical treatment of C.V.A was mainly Acupuncture (25%), Paper of Chinese herbs (22%), Chinese physiotherapy (14%), Extract of Chinese herbs (11%). 5. Oriental medical physiotherapy for C.V.A was mostly E.S.T., Kinesiatrics, electric negative therapy, others Aerohydrotherapy, interferential current therapy (I.C.T.), Carbon, Samhogi, T.E.N.S., Ultra-sound, Infra-red, Microwave, T.D.P., Ultraviolet, S.S.P., Chinese herbs beth, Prarffin bath, Magnetic treatment and tractions.