• The Journal of the Korea Contents Association
• /
• v.7 no.11
• /
• pp.76-83
• /
• 2007

In the sequentially rotated array antennas, the characteristics of antenna gain, axial ratio and cross polarization have been analyzed with a varying of sequential array constant(number of array element, figure of rotation) respectively. Where the antenna element of array is a probe feeding, LHCP truncated microstrip antenna whose resonant frequency is in 11.85GHz. The simulation results of 23 SRA antennas((M=2, 3, 4, 6, 8), $(1\leqP\leqM)$) has shown as follows. The widest 3dB bandwidth of axial ratio appears at P=2 which is in-dependant of M, the highest antenna gain appears when a sequential array constant has a pair of (2, 1), (3, 2), (4, 1), (6, 3), (8, 1) respectively. Specially, all of the SRA antenna appear very poor characteristics in case of M=P. Therefore the SRA antenna has to be designed as selecting a optimal sequential array constant among a lot of simulation data.

• Korean Journal of Human Ecology
• /
• v.17 no.2
• /
• pp.305-313
• /
• 2008

This subject investigated visual evaluation of preference and fitness level of set-in sleeve in sleeve types(form)and studied suitable sleeve type at silhouette and targeted female students in twenties. The results of study were as follows: 1. Visual evaluation factors in set-in sleeve of sleeve types were selected 6 factors; the 1st factor is decorativeness, the 2nd factor is attractiveness, the 3rd factor was activeness, the 4th factor was feminine, the 5th factor was charming and 6th factor was a figural element. Decorativeness and attractiveness factors in visual evaluation of sleeve types were the most important level. 2. The visual evaluation differences of sleeve types in set-in sleeve were as follows; in the 1st factor, S and P2 were the most decorative sleeve type. in the 2nd factor, S, P2 and P3 are the most attractive sleeve type. in the 3rd factor, B and P3 were the most active sleeve type. in the 4th factor, L was the most feminine sleeve type. in the 5th factor, P1, L and P3 were charming sleeve type. in the 6th factor, P3 was evaluated that it shows narrowened shoulder sleeve types. 3. The analysis result of preference and wearing level in each sleeve types were as follows. 20's female university students like to wear S, P1, P2 and P3 sleeve types and the most favorite sleeve types are S, P2 and P3. 4. The analysis result of silhouette set-in sleeve in sleeve types; S, B and P2 in H-type silhouette, P2, S and P1 in A-type silhouette, B and P3 in O-type silhouette, L and P3 in X-types silhouette were show the most suitable sleeve types.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.8 no.2
• /
• pp.23-38
• /
• 2004

We consider finite element methods applied to a class of quasi parabolic integro-differential equations in $R^d$. Global strong superconvergence, which only requires that partitions are quasi-uniform, is investigated for the error between the approximate solution and the Sobolev-Volterra projection of the exact solution. Two order superconvergence results are demonstrated in $W^{1,p}(\Omega)\;and\;L_p(\Omega)$, for $2\;{\leq}p\;<\;{\infty}$.

• Animal Bioscience
• /
• v.34 no.4
• /
• pp.652-661
• /
• 2021

Objective: Wooden breast (WB) is a novel myopathy affecting modern broiler chickens, which causes substantial economic losses in the poultry industry. The objective of this study was to evaluate the effect of WB abnormality on meat quality, redox status, as well as the expression of genes of the nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway. Methods: A total of 80 broilers (Ross 308, 42 days of age, about 2.6 kg body weight) raised at Jiujin farm (Suqian, Jiangsu, China) were used. Twelve unaffected (no detectable hardness of the breast area) and twelve WB-affected (diffuse remarkable hardness in the breast muscle) birds were selected from the commercial broiler farm according to the criteria proposed by previous studies. Results: The results indicated that WB showed histological lesions characterized by fiber degeneration and fibrosis, along with an increase of muscle fiber diameter (p<0.05). Moreover, higher pH value, lightness, yellowness, drip loss and cooking loss were observed in the WB group (p<0.05). Compared with the normal breast (NOR) group, the WB group showed higher formation of reactive oxygen species (p<0.05), increased level of oxidation products and antioxidant activities (p<0.05), accompanied with mitochondrial damages and lower mitochondrial membrane potential (p<0.05). Meanwhile, the relative mRNA expressions of Nrf2 and its downstream antioxidant genes including heme oxygenase-1, NAD(P)H qui none dehydrogenase 1, glutathione peroxidase, superoxide dismutase, and glutamate-cysteine ligase were higher than those of the NOR group (p<0.05). Conclusion: In conclusion, WB myopathy impairs meat quality by causing oxidative damages and mitochondrial dysfunction in broilers, even though the activated Nrf2/antioxidant response element pathway provides protection for the birds.

• The Journal of the Acoustical Society of Korea
• /
• v.42 no.1
• /
• pp.1-6
• /
• 2023

Sound radiated from a structure in vibration is an important physical characteristic to evaluate vibro-acoustic problem. Although sound radiation power can be typically obtained by intensity measurement, long measuring time and strict measuring condition remain difficult. As an alternative method, simulation-based estimation can be taken into account and its accuracy is known to be acceptable. However, difficulty still lies in that specialized softwares may be necessary to obtain sound radiation power and radiation efficiency. In this context, this study suggests two methods using an ordinary FE method to calculate sound radiation power. They are well-known reciprocity technique and p-p method, which are basically test methods. It is shown that either method can practically estimate sound radiation in the frame of conventional Finite Element Method (FEM). The methods and their corresponding limit are discussed with some results.

• Honam Mathematical Journal
• /
• v.45 no.4
• /
• pp.678-681
• /
• 2023

Let G be a cyclic group of prime power order p^k, and let I be the augmentation ideal of the integral group ring ℤ[G]. We define a derivation on ℤ/p^kℤ[G], and show that for 2 ≤ n ≤ p, an element α ∈ I is in Iⁿ if and only if the i-th derivative of the image of α in ℤ/p^kℤ[G] vanishes for 1 ≤ i ≤ (n - 1).

• Journal of applied mathematics & informatics
• /
• v.17 no.1_2_3
• /
• pp.679-687
• /
• 2005

In this paper we shall give a new definition for a quasi-power module P(M) and discuss some properties for P(M). The quasi-power module P(M) is a direct sum of invertible quasi-submodules C(H)'s of P(M) and then the quasi-submodule C(H) is also a direct sum of strongly cyclic quasi-submodules of C(H). When M is a quasi-perfect right R-module, we shall see that the quasi-power module P(M) is invertible.

• Communications of the Korean Mathematical Society
• /
• v.9 no.2
• /
• pp.467-489
• /
• 1994

Let $\Omega$ be a closed and bounded polygonal domain in R$^2$, or a closed line segment in R$^1$ with boundary $\Gamma$, such that there exists an invertible mapping T : $\Omega$ \longrightarrow $\Omega$ with the following correspondence: x$\in$$\Omega$ ↔ x = T(x) $\in$$\Omega$, (1.1) and (1.2) t $\in$ U$\sub$p/($\Omega$) ↔ t = to T$\^$-1/ $\in$ U$\sub$p/($\Omega$), where $\Omega$ denotes the corresponding reference elements I = [-1,1] and I ${\times}$ I in R$^1$ and R$^2$ respectively, (1.3) U$\sub$p/($\Omega$) = {t : t is a polynomial of degree $\leq$ p in each variable on $\Omega$}, and (1.4) U$\sub$p/($\Omega$) = {t : t = to T $\in$ U$\sub$p/($\Omega$)}.(omitted)

• Review of KIISC
• /
• v.3 no.1
• /
• pp.86-90
• /
• 1993

Finite field GF$(2^n)5에서 정의된 elliptic curve가 있을때 그 curve위의 어떤 point p를 k배하는 연산은 암호론에서 매우 자주 쓰여진다. 이때 optimal normal bases를 이용하여 GF$(2^n)의 element를 표현하고, 또 elliptic curve를 선택할 때 animalous curve가 되도록 한다면, 기존이 방법 보다 매우 빠르게 k P를 구할 수 있다.

• The Journal of Society for e-Business Studies
• /
• v.25 no.1
• /
• pp.35-43
• /
• 2020

Smart grid aims to achieve efficient energy-related operations. Smart grid will become a central component of Smart city that aims to improve citizens' quality of life. This paper validates that smart grid at matured state is the state where smart grid is naturally integrated into smart grid. Also, this paper describes smart grid as an essential element of smart city. This paper discusses necessary social infrastructure and investigates necessary technological features.