• Kyungpook Mathematical Journal
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• 제57권1호
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• pp.109-124
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• 2017

In this article the Srivastava-Owa-Ruscheweyh fractional derivative operator $\mathcal{L}^{\alpha}_{a,{\lambda}}$ is applied for defining and studying some new subclasses of analytic functions in the unit disk E. Inclusion results, radius problem and other results related to Bernardi integral operator are also discussed. Some applications related to conic domains are given.

• 한국입자에어로졸학회지
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• 제7권4호
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• pp.123-130
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• 2011

Previous designs of conventional aerodynamic lenses have a limitation of narrow range of focusable particle size, e.g. 30 to 300nm or 3 to 30nm. To enlarge the focusable size range to 30-3000nm, it is necessary to avoid a significant loss of particles larger than 300nm inside the lenses. From numerical simulations on size-resolved particle trajectories, we confirmed that the traveling losses of such large particles could be avoided only when the radial position of particles approaching the orifice lens was near the lens axis. Hence, we designed the lens system consisting of a converging-diverging nozzle and 7 orifices to fulfill the requirement. In particular, the orifices were aligned in a way that their diameters were descending and ascending to the downstream. As a result, 30-2800nm particles can be focused to the particle beam of 0.2mm or less in radius with above 85% transmission efficiency. Even $10{\mu}m$ particles can be focused with 74% of transmission efficiency.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3805-3809
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• 2012

Results for molecular dynamics simulation method of small liquid drops of argon (N = 1200-14400 molecules) at 94.4 K through a Lennard-Jones intermolecular potential are presented in this paper as a preliminary study of drop systems. We have calculated the density profiles ${\rho}(r)$, and from which the liquid and gas densities ${\rho}_l$ and ${\rho}_g$, the position of the Gibbs' dividing surface $R_o$, the thickness of the interface d, and the radius of equimolar surface $R_e$ can be obtained. Next we have calculated the normal and transverse pressure tensor ${\rho}_N(r)$ and ${\rho}_T(r)$ using Irving-Kirkwood method, and from which the liquid and gas pressures ${\rho}_l$ and ${\rho}_g$, the surface tension ${\gamma}_s$, the surface of tension $R_s$, and Tolman's length ${\delta}$ can be obtained. The variation of these properties with N is applied for the validity of Laplace's equation for the pressure change and Tolman's equation for the effect of curvature on surface tension through two routes, thermodynamic and mechanical.

• Kyungpook Mathematical Journal
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• 제48권3호
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• pp.359-366
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• 2008

Let A(p) be the class of functions $f\;:\;z^p\;+\;\sum\limits_{j=1}^{\infty}a_jz^{p+j}$ analytic in the open unit disc E. Let, for any integer n > -p, $f_{n+p-1}(z)\;=\;z^p+\sum\limits_{j=1}^{\infty}(p+j)^{n+p-1}z^{p+j}$. We define $f_{n+p-1}^{(-1)}(z)$ by using convolution * as $f_{n+p-1}\;*\;f_{n+p-1}^{-1}=\frac{z^p}{(1-z)^{n+p}$. A function p, analytic in E with p(0) = 1, is in the class $P_k(\rho)$ if ${\int}_0^{2\pi}\|\frac{Re\;p(z)-\rho}{p-\rho}\|\;d\theta\;\leq\;k{\pi}$, where $z=re^{i\theta}$, $k\;\geq\;2$ and $0\;{\leq}\;\rho\;{\leq}\;p$. We use the class $P_k(\rho)$ to introduce a new class of multivalent analytic functions and define an integral operator $L_{n+p-1}(f)\;\;=\;f_{n+p-1}^{-1}\;*\;f$ for f(z) belonging to this class. We derive some interesting properties of this generalized integral operator which include inclusion results and radius problems.

• 한국해양학회지:바다
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• 제11권4호
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• pp.152-157
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• 2006

2004년 4월부터 2005년 3월까지 전라북도 김제시 심포면 갯벌에 서식하는 백합의 연령과 성장을 조사하였다. 백합의 패각에 나타나는 윤문은 년 1회 형성되며, 주된 윤문 형성시기는 2월$\sim$4월임을 확인할 수 있었다. 초륜의 형성기간은 약 6개월(0.5년)로 나타났으며, 각장(SL)과 각고(SH)간의 관계는 SH=0.8103 SL + 0.5145$(R^2=0.991)$이고, 각장과 각폭(SW)간의 관계는 SW=0.4897 SL + 0.0315 $(R^2=0.976)$이며, 각장과 전중량(TW)간의 관계는 $TW=2.9195\times10^{-4}\;SL^{2.9547}\;(R^2=0.991)$로 나타났다. 연령 (t)에 대한 각장(SL)의 Bertalanffy 성장식은 $SL_t=104.9(l-e^{-0.2235(t+0.7677)})$였으며, 전중량(TW)의 Bertalanffy 성장식은 $TW_t=280.8(l-e^{-0.2235(t+0.7677)})^{2.9547}$로 추정되었다.

• 한국수산과학회지
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• 제56권6호
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• pp.798-809
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• 2023

In this study, we evaluated the impacts of land-based pollution sources on seawater and shellfish in the Jindongman area after 20.5 mm and 90.6 mm rainfall events. We analyzed sanitary indicator microorganisms used in survey management, such as total coliform, fecal coliform, Escherichia coli, and male-specific coliphage in Waste water treatment plant (WWTP), major inland pollution source,s seawater, and shellfish for 4 days after rainfall events. Our results showed that the range of coliform group and fecal coliform was 1.8-49 and <1.8-4.5 MPN (most probable number)/100 mL, respectively, after rainfall events in WWTP discharge water. Furthermore, the radius of the calculated impacted area of major inland pollution sources ranged from 5 to 798 m after 20.5 mm of rainfall and 30 to 1,031 m after 90.6 mm of rainfall. The fecal coliform of seawater at 30 stations in the shellfish growing area and areas adjacent to four stations was <1.8-130 and from <1.8-79 MPN/100 mL, respectively. The E. coli level of shellfish at 7 stations in the shellfish growing area was <18-220 MPN/100 g.

• 한국패류학회지
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• 제24권3호
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• pp.189-197
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• 2008

In order to develop the sustainable ecological management, short-necked clams, Ruditapes philippinarum, were collected from Yoengi coast in Tongyoeng, Korea. The growth of the clam was estimated as: $L_f=68.08{\cdot}(1-e^{-0.145(t+0.324)})$ from ring radius composition of shell. Instantaneous co-efficiency of total mortality and natural mortality were calculated as: 0.991/year and 0.494/year, respectively. The age of the clams from the first capture was estimated to be 3.28. The total biomass was estimated to be 212 MT in the fisheries area (6.4 ha). Applied by these parameters, the annual recruit biomass and the current yield per recruit were calculated to be 649.5 individual/$m^2$ and $0.7\;g/m^2$, respectively. The current fishing intensity was much lower for maximum sustainable yield and acceptable biological catch. Although higher yield per recruit could be achieved by increasing fishing intensity, it is favorable to retain the current fishing intensity because of the unique fishing attitude on Yeongi coast in Tongyoeng, Korea.

• 한국패류학회지
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• 제28권2호
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• pp.109-116
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• 2012

In order to understand the effect of introduction of oyster rack culture on natural short-necked clam, Ruditapes philippinarum, stock, we investigated the status of natural clam stock prior to introduction of oyster rack culture at Yeongheung Coast of Wando Island. The growth equation of the clam was estimated as: $L_t=61.46{\cdot}(1-e^{-0.172(t+0.155)})$ from ring radius composition of shell. Instantaneous coefficient of total mortality and natural mortality were calculated as: 2.4087/year and 0.478/year, respectively. The age at first capture was estimated to be 2.55 year. The total biomass was estimated to 3.23 ton in the bed (0.8 ha). Applied by these parameters, the annual recruit biomass and the current yield per recruit (Y/R) was corresponded to $114.7individuals/m^2$ and $92.0g/m^2$, respectively. Maximum sustainable yield (MSY) was estimated 0.77 ton/year which was close to annual catches, 0.74 ton/year, in the area.

• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.975-979
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• 2012

Structure and Dynamics of dilute two-dimensional (2D) ring polymer solutions are investigated by using discontinuous molecular dynamics simulations. A ring polymer and solvent molecules are modeled as a tangent-hard disc chain and hard discs, respectively. Some of solvent molecules are confined inside the 2D ring polymer unlike in 2D linear polymer solutions or three-dimensional polymer solutions. The structure and the dynamics of the 2D ring polymers change significantly with the number ($N_{in}$) of such solvent molecules inside the 2D ring polymers. The mean-squared radius of gyration ($R^2$) increases with $N_{in}$ and scales as $R{\sim}N^{\nu}$ with the scaling exponent $\nu$ that depends on $N_{in}$. When $N_{in}$ is large enough, ${\nu}{\approx}1$, which is consistent with experiments. Meanwhile, for a small $N_{in}{\approx}0.66$ and the 2D ring polymers show unexpected structure. The diffusion coefficient (D) and the rotational relaxation time ($\tau_{rot}$) are also sensitive to $N_{in}$: D decreases and $\tau$ increases sharply with $N_{in}$. D of 2D ring polymers shows a strong size-dependency, i.e., D ~ ln(L), where L is the simulation cell dimension. But the rotational diffusion and its relaxation time ($\tau_{rot}$) are not-size dependent. More interestingly, the scaling behavior of $\tau_{rot}$ also changes with $N_{in}$; for a large $N_{in}$ $\tau_{rot}{\sim}N^{2.46}$ but for a small $N_{in}$ $\tau_{rot}{\sim}N^{1.43}$.

• 수산해양기술연구
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• 제42권1호
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• pp.19-29
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• 2006

To investigate the fishery and fishing ground environment of red horsehead (Branchiostegus japonicus), the author analyzed the fishery data and examined the amount of catches and oceanic environment on the adjacent seas of Jeju island and East China Sea. It was turned out that the favourable season of the red horsehead fishery is the month from March to June, the main fishing ground is located in 60 mile radius from the position $32.5^{\circ}N,\;125.7^{\circ}E$. The bottom seawater temperature in fishing ground was shown between $l3^{\circ}C\;and\;16^{\circ}C$, the salinity was appeared between 33.5 and 34.0psu without the seasonal variation of the year. Concentrations of materials(e.g, $NO_3^-\;and\;NO_2^-$) in spring and summer time in main fishing ground were higher than any other seasons, but that of phospheric materials were lower than any other seasons. Concentrations of $chlorophyll\;-\;{\alpha}$ in the main fishing ground was the highest in spring and summer at the surface layer, but the vertical profile of the $chlorophyll\;-\;{\alpha}$ concentrations in all seasons were not variable at bottom layer. Mean density of zooplankton abundance according to the vertical structure was higher and much stable in summer and autumn than spring and winter.