• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1700-1707
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• 2015

The effects of drying temperature on drying characteristics of soybeans with different grain sizes [6.0 (S), 7.5 (M), and 9.0 mm (L) (${\pm}0.2$)] with 25.0% (${\pm}0.8$) initial moisture content were studied. Drying temperatures varied at 25, 35, and $45^{\circ}C$, with a constant air velocity (13.2 m/s). Thin-layer drying models were applied to describe the drying process of soybeans. The Midilli-Kucuk model showed the best fit ($R^2$ >0.99). Based on the model parameters, drying time to achieve the target moisture content (10%) was successfully estimated. Drying time was strongly dependent on the size of soybeans and the drying temperature. The effective moisture diffusivity ($D_{eff}$) was estimated by the diffusion model based on Fick's second law. $D_{eff}$ values increased as grain size and drying temperature increased due to the combined effect of high temperatures and high drying rates, which promote compact tissue. Deff values of S, M, and L estimated were in the range of $0.83{\times}10^{-10}$ to $1.51{\times}10^{-10}m^2/s$, $1.17{\times}10^{-10}$ to $2.17{\times}10^{-10}m^2/s$, and $1.53{\times}10^{-10}$ to $2.95{\times}10^{-10}m^2/s$, respectively, whereas activation energy ($E_a$) based on drying temperature showed no significant differences in the size of soybeans.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.3
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• pp.21-27
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• 1982

A kinetical approach for the non-enzymatic browning reaction of the dried file-fish was studied. The reaction rates revealed a tend to increase with increasing water activity and showed the maximum at $0.75\;a_w$ The activation energies obtained from the Arrhenius plot ranged 12.5 to 16.5 Kcal/mole. From these energies of activation, the $Q_{10}$ values at $45^{\circ}C$ showed 1.9 to 2.3 and both activation energy and $Q_{10}$ values were reduced with increase in $a_w$ Shelf-lives, the time to reach an 0.15 O.D./g solid at which severe brown color change could be de ectable, decreased rapidly as the temperature and water activity increase. A storage study under a square-wave fluctuating temperature condition (at 35 and $55^{\circ}C$ periodically with 7 days interval), the rate constants at all water activities used in the experiments were higher than those at $45^{\circ}C$, the mean temperature of the cycle which affects other kinetic parameters including activation energies, $Q_{10}$ values and finally the shelf-lives. The data obtained from the fluctuating temperaure storage study will be used in prediction of shelf-life. The shelf lives assessed at $25^{\circ}C$ from the accelerated shelf-life tests ranged from 179 daysat $0.75\;a_w$ to 302 days at $0.44\;a_w$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.1
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• pp.54-62
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• 2010

With the aim of developing and indoor overwintering technique for Pearl oyster, Pinctada fucata martensii, the metabolic rates of young oysters (52.4-83.0 mm in shell length) were measured for 2 weeks at water temperatures of 8, 10, 12, and $14^{\circ}C$. The filtration rate (FR) ranged 0 to $4.84\;L\;h^{-1}gDW^{-1}$ (mean, $0.02{\pm}0.06 $ to $3.12{\pm}1.45$), with significant changes observed over thme except for the case of a water temperature of $14^{\circ}C$. Respiration rate (R) ranged from 0 to $2.370\;mgO2\;h^{-1}gDW^{-1}$ (mean, 0 to $1.77{\pm}0.37$), with significant respiratory disorders observed at temperatures below $12^{\circ}C$; in contrast, the rate increased on the $14^th$ day of the experiment in the case of a temperature of 14$^{\circ}C$. No significant difference was observed among the different water temperatures in terms of excretion rate (E) or absorption efficiency (Abs.eff), except for a significant decrease in aerobic metabolism in the case of water temperature of $8^{\circ}C$. The estimated scope for growth (SFG) ranged from -9.1 to $126.9\;J\;h^{-1}gDW^{-1}$ (mean. $-4.1{\pm}2.6$ to $82.85{\pm}42.6$). A significant energy Joss was found at $8^{\circ}C$, with negative SFG observed throughout the experiment and a gradual energy decrease observed over time at water temperatures of $10^{\circ}C$ and 120C. However. SFG remained positive throughout the experiment in the case of $14^{\circ}C$. The estimated minimum energy requirement, assessed from energy expenditure, is $8.00-34.24\;J\;h^{-1}gDW^{-1}$ (mean, $17.67{\pm}6.17$). In conclusion, the lowest temperature suitable for indoor overwintering is above $14^{\circ}C$.

• The Korean Journal of Physiology
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• v.23 no.1
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• pp.89-98
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• 1989

In order to produce antibody for use in radioimmunoassay of gastrin in physiological concentration, four rabbits of New Zealand white were immunized with synthetic human gastrin-17-I conjugated to hemocyanin with EDC. Among them, only one rabbit produced antibody that could bind 50% of $^{125}I-gastrin$ at a final dilution of 1:25,000. $^{125}I-gastrin$ was prepared with synthetic human gastrin-17-I and $NaI^{125}$ by lactoperoxidase technique. The product was then purified on a column of Sephadex Gl5/G5O (7:3, w/w) followed by a column of DEAE sephadex A-25. The specific radioactivity of the purified $^{125}I-gastrin$ was in the range of 347-1429 ${\mu}Ci/nmole$ when determined by the self-displacement method. The effective affinity constant $(K_{eff})$, total binding sites (N), heterogeneity index $({\alpha})$ and average affinity constant $(K_{0})$ of the anti-gastrin serum calculated from Scatchard plot as well as Sips plot were $1.77{\times}10^{11}/M$, 255 nM, 0.84 and $0.79{\times}10^{11}/M$, respectively. When radioimmunoassay was performed with the anti-gastrin serum, it was confirmed that the mean concentration of gastrin immunoreactivity in plasma was increased by feeding in humans and rats, and also increased by bombesin administration in rats. The results indicate that the anti-gastrin serum produced in the present investigation is suitable for radioimmunological determination of gastrin in physiological concentration.

• Nuclear Engineering and Technology
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• v.52 no.3
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• pp.469-476
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• 2020

Research reactors in-core experimental facilities are designed to provide the highest steady state flux for user's irradiation requirements. However, fuel conversion from highly enriched uranium (HEU) to low enriched uranium (LEU) driven by the ongoing effort to diminish proliferation risk, will impact reactor physics parameters. Preserving the reactor capability to produce the needed flux to perform its intended research functions, determines the conversion feasibility. This study investigates the neutron flux in the central experimental facility of two material test reactors (MTR), the IAEA generic10 MW benchmark reactor and the 22 MW s Egyptian Test and Research Reactor (ETRR-2). A 3D full core model with three uranium enrichment of 93%, 45%, and 20% was constructed utilizing the OpenMC particle transport Monte Carlo code. Neutronics calculations were performed for fresh fuel, the beginning of life cycle (BOL) and end of life cycle (EOL) for each of the three enrichments for both the IAEA 10 MW generic reactor and core 1/98 of the ETRR-2 reactor. Criticality calculations of the effective multiplication factor (K_eff) were executed for each of the twelve cases; results show a reasonable agreement with published benchmark values for both reactors. The thermal, epithermal and fast neutron fluxes were tallied across the core, utilizing the mesh tally capability of the code and are presented here. The axial flux in the central experimental facility was tallied at 1 cm intervals, for each of the cases; results for IAEA 10 MW show a maximum reduction of 14.32% in the thermal flux of LEU to that of the HEU, at EOL. The reduction of the thermal flux for fresh fuel was between 5.81% and 9.62%, with an average drop of 8.1%. At the BOL the thermal flux showed a larger reduction range of 6.92%-13.58% with an average drop of 10.73%. Furthermore, the fission reaction rate was calculated, results showed an increase in the peak fission rate of the LEU case compared to the HEU case. Results for the ETRR-2 reactor show an average increase of 62.31% in the thermal flux of LEU to that of the HEU due to the effect of spectrum hardening. The fission rate density increased with enrichment, resulting in 34% maximum increase in the HEU case compared to the LEU case at the assemblies surrounding the flux trap.

• Korean Journal of Optics and Photonics
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• v.15 no.4
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• pp.375-384
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• 2004

Switching phenomenon of a three-waveguide optical coupler was analyzed by using the coupled mode theory, and the coupling-length of the device was calculated by means of the FDM. CPW traveling-wave electrodes were designed by the CMM and SOR simulation techniques so as to satisfy the conditions of phase-velocity and impedance matching. Traveling-wave modulators were fabricated on a z-cut LiNbO$_3$ substrate. Ti was in-diffused in LiNbO$_3$ to make waveguides and Au electrodes were built on the waveguides by the electroplating technique. Insertion loss and switching voltage of the optical modulator were about 4 ㏈ and 15.6V. Network analyzer was used to obtain S parameters and corresponding RF response. From the measurement, parameters of the traveling-wave electrodes were extracted as such Z$_{c}$=39.2 $\Omega$, Neff=2.48, and a0=0.0665/cm((GHz) (1/2)). The measured optical response R(w) was compared with the theoretically estimated and both responses were shown to agree well. The measurement results revealed that the ㏈ bandwidth turned out to be about 13 GHz.

• Food Science of Animal Resources
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• v.20 no.4
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• pp.303-310
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• 2000

In vitro 소화시 계란 성분이 anti-Y ruckeri IgY 항세 활성을 안정화시키는데 어떡해 관여하는지를 SDS-PAGE와 ELISA로 조사한 결과는 다음과 같다. Anti-Y ruckeris IgY 항체와 난황 및 난백으로 혼합 후 펩신으로소화시킨 후 경우 1시간 후 난황 및 난백이 혼합된 시료에서 모두 anti-Y ruckeri IgY 항체의 heavy chain과 light chain이 분해는 되었지만 어느 정도 밴드를 관찰할 수있었으며, anti-Y, ruckeri IgY 항체 활성 측정한 결과 난황시료는 35%, 난백시료는 61%의 항체 활성을 유지시켰다. Anti-Y ruckeri IgY 항체와 오보알부민, 오보뮤우신, 라이소자임 및 오보뮤코이드를 혼합 한 후 펩신으로 소화시킨 경우 1시간 우에는 anti-Y, ruckeri IgY항체의 heavy chain의 밴드르 fdjsm 정도 볼 수 있는 형태로 나타났으며, anti-Y, ruckeri IgY 항체의 light chain는 오보뮤우신 및 오보뮤코이드가 홉합되어 펩신으로 소화시킨 경우 1시간 후에는 밴드를 거의 볼수 없었으나 오보알부민 오보트란스훼린 및 라이소자임에 혼합된 시료에서 밴드를 관찰할수 있었다. 특히 라이소자임과 오보트란스훼린의 경우 펩신 호화 2시간 우에도 anti-Y, ruckeri IgY 항체의 light 밴드가 관찰되었다. 펩신소화 1시간 후에 난백성분이오보알부민, 오보뮤우신, 라이소자임, 오보트란스웨린 및 오부뮤코이드 중에서 단지 오보트란스훼린만이 38%의 anti-Y, ruckeri IgY 항체 활서을 보인후 2시간 후에도 15% 정동의 활성을 나타내었다. anti-Y, ruckeri IgY항체와 난백 및 전란을 혼합한 다음 무지개송어 위 추출액으로 소화시 2시간 후에 난백은 14%, 전란은 69%로 anti-Y, ruckeri IgY 항체 활성을 유지시킨 것으로 나타났다.X> $e_{I}$ WPi_BE_QE]]]]]로 상징하며 WLWQ에 적용되는 몇 가지 제약을 관찰하고 이를 일반적인 언어원리로 설명한다. 첫째, XP는 주어로만 해석되는데 그 이유는 XP가 목적어 혹은 부가어 등 다른 기능을 할 경우 생략 부위가 생략의 복원 가능선 원리 (the deletion-up-to recoverability principle)를 위배하기 때문이다. 둘째, WLWQ가 내용 의문문으로만 해석되는데 그 이유는 양의 공리(the maxim of quantity: Grice 1975) 때문이다. 평서문으로 해석될 경우 WP에 들어갈 부분이 XP의 자질의 부분집합에 불과하므로 명제가 아무런 정보제공을 하지 못한다. 반면 의문문 자체는 정보제공을 추구하지 않으므로 앞에서 언급한 양의 공리로부터 자유롭다. 셋째, WLWQ의 XP는 주제어 표지 ‘는/-은’을 취하나 주어표지 ‘가/-이’는 취하지 못한다(XP-는/-은 vs. XP-가/-이). 이는 IP내부 에 비공범주의 존재 여부에 따라 C의 음운형태(PF)가 시성이 정해진다는 가설로 설명하고자 했다. WLWQ에 대한 우리의 논의가 옳다면, 본 논문은 다음과 같은 이론적 함의를 기닌다. 첫째, WLWQ의 존재는 생략에 대한 두 이론 즉 LF 복사 이론과 PF 삭제 이론 중 전자의 입장을 지지한다. 둘째, WP를 XP로부터 복원할 때 부분 자질만 복사된다. 이는 어휘가 통사층위로 들어온 이후에도 어휘 자질들이 완전히 동결되는 것이 아니라 계속 지시될 수 있다는 가설을 지지한다.

• Korean Journal of Materials Research
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• v.27 no.10
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• pp.518-523
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• 2017

In commercial solar cells, the pattern of the front electrode is critical to effectively assemble the photo generated current. The power loss in solar cells caused by the front electrode was categorized as four types. First, losses due to the metallic resistance of the electrode. Second, losses due to the contact resistance of the electrode and emitter. Third, losses due to the emitter resistance when current flows through the emitter. Fourth, losses due to the shading effect of the front metal electrode, which has a high reflectance. In this paper, optimizing the number of finger on a $4{\times}4$ solar cell is demonstrated with known theory. We compared the short circuit current density and fill factor to evaluate the power loss from the front metal contact calculation result. By experiment, the short circuit current density($J_{sc}$), taken in each pattern as 37.61, 37.53, and $37.38mA/cm^2$ decreased as the number of fingers increased. The fill factor(FF), measured in each pattern as 0.7745, 0.7782 and 0.7843 increased as number of fingers increased. The results suggested that the efficiency(Eff) was measured in each pattern as 17.51, 17.81, and 17.84 %. Throughout this study, the short-circuit current densities($J_{sc}$) and fill factor(FF) varied according to the number of fingers in the front metal pattern. The effects on the efficiency of the two factors were also investigated.

• Journal of the Korean Magnetics Society
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• v.15 no.1
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• pp.17-20
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• 2005

The influence of $O_2$ partial pressure on saturation mgnetization, coercivity, anisotropy field and effective permeability (over 1GHz) of as-deposited Co-Fe-Al-O thin films, which were fabricated by RF magnetron reactive sputtering method, were investigated. The $Co_{69.9}Fe_{20.5}A_{14.4O_{5.2}$ thin film fabricated at $O_2$ partial pressure of 4% exhibits the best magnetic softness with saturation magnetization 4${$pi}$Ms of 18.1 kG, coercivity of 0.82 Oe, anisotropy field ($H_k$) of Oe, and effective permeability (${\mu}_{eff}$) about 1,024 above 1 GHz. the electrical resistivity of Co-Fe-Al-O thin films were increased with increasing $O_2$ partial pressure, the electrical resistivity of $Co_{69.9}Fe_{20.5}A_{14.4O_{5.2}$ thin film with the best soft magnetic properties was 560.7 ${\mu}{\Omega}$am. Therefore, It is assumed that the good soft magnetic properties of $Co_{69.9}Fe_{20.5}A_{14.4O_{5.2}$ thin film results from high electrical resistivity and large anisotropy field.

• Journal of the Korean Magnetics Society
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• v.20 no.1
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• pp.18-23
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• 2010

Ferromagnetic resonance (FMR) measurement is an important experimental technique for the study of magnetic dynamics. We designed and set up the vector network analyzer ferromagnetic resonance (VNA-FMR) measurement system with home made coplanar waveguides (CPW). We examined 10-, 20-, 40-nm thick Py thin films to test the performance of the VNA-FMR measurement system. We measured S-parameter (transmission/reflection coefficient) of Py thin films on a CPW. Resonance frequency is investigated from 2.5 to 7 GHz for a field range from 0 to 490 Oe. The VNA-FMR data shows the resonance frequency increment when the external magnetic field increases. We also investigated Gilbert damping constant of Py thin film using resonance frequency (${\omega}_r$) and linewidth ($\Delta\omega$). After investigating dependence of thickness, we find that an decrease in S-parameter intensity as Py thin film thickness decreases. And the FMR results show that the effective saturation magnetization, $M_{eff}$, increase from 7.205($\pm$0.013) kOe to 7.840($\pm$0.014) kOe, while the film thickness varies from 10 to 40 nm.