• Membrane Journal
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• v.17 no.4
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• pp.345-351
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• 2007

In this research, by using the fluorine gas, the poly(ether sulfone) (PES), the polysulfone (PSf), and the poly-vinylidenefluoride (PVDF) membranes were modified to improve the performance of the optional Gas-Liquid Contactor The SEM, surface contact angle, XPS, and the water transmission minimum pressure test was performed in order to examine the characteristics of which is surface modified. As a result of looking into the surface morphology of from the SEM measurement, we could know that the roughness of the membrane surface increased as the fluorine processing time increased. $-CH_2$, and the perfluoro group of $-CH_3$ were chemically combined with the surface fluorine conversion film surface and the hydrophobicity was exposed to be increased. Moreover, we could know that as the surface fluorinated processing time increased from the surface contact angle and water transmission minimum pressure test, the measured value increased and the overall characteristics were improved.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.109-109
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• 2022

The global population is increasing every year, and the amount of food waste is also increasing. Direct landfilling of food waste has been prohibited since 2005, and in accordance with the London Convention in 2013, the discharge of livestock manure, sewage sludge, and food waste into the sea is prohibited. In the case of incineration to treat the discharged food waste, the heat point is lowered due to the moisture in the food waste itself, so fuel must be added. Therefore, this study was conducted to get basic data for setting the limit of application by investigating the growth and yield of crops after treating food waste dry powder mixed fertilizer (MF) on red pepper. In the experiment, continuous cultivation was carried out for two years in 2021 (1st year) and 2022 (2nd year). The treatment groups were set as Not Treatment (NT), Chemical Fertilizer (CF), Mixed Fertilizer (MF), Mixed Fertilizer×2 (MF×2). After harvest, crop growth and yield were investigated. As a result of the 1st years of growth survey, CF, MF, MF×2 show significant difference in shoot length compared to NT. About fresh weight and dry weight, CF show significant difference compared to NT. The 2nd years of growth survey, the shoot and root length, fresh weight did not show significant difference with NT. In case of dry weight, MF is significant increased compared to NT. As a result of the yield survey of the 1st year, all treatment groups did not show a significance in yield compared to the NT. In case of 2nd year, all treatment groups show significantly increased value compared to NT. The yield of MF was highest among the treatment groups. In the future, it is thought that it is necessary to quantitatively evaluate the effect of food waste dry powder mixed fertilizer through additional experiments and continuous cultivation, and to establish an appropriate amount of use and establishment of a manual based on this.

• Journal of Nutrition and Health
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• v.25 no.7
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• pp.597-607
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• 1992

The present study examined effects of caffeine on coronary circulation myocardial oxygen me-tabolism and calcium release in isolated perfused guinea pig hearts. Intracoronary caffeine({{{{ {10 }^{-5 } }}}}∼{{{{ { 10}^{-3 } }}}}M) was employed for 10 minutes to measure coronary perfusate flow(CF) and coronary vascular sresistance(CVR) at a constant coronary perfusion pressure of 80 cmH2O Perfusate myocardial oxygen consumption(MVO2) and percent oxygen extraction(%EC2) were calcula-ted. In addition calcium contents in both perfusate samples were measured to calculate calcium release in coronary venous effluent. Caffeine significantly decreased CF and increased CVR during 10 minutes of caffeine perfusion regardless of dose of caffeine perfused exhibiting time-response. While % EO2 was significantly enhanced with caffeine MVO2 was markedly reduced. The coronary venous perfusate pH dcreased during the perfusion with caffeine. These changes were consistent with caffeine-induced metabolic acidosis. Calcium release appeared to be dose-dependent and high dose of caffeine greatly increased venous calcium release even 2 minutes after perfusion with carffeine. These finding in dicate that caffeine produced coronary vasoconst-riction with increased calcium release in isolated perfused guinea pig hearts. Additionaly this vasoconstrictor response mignt be due tin part to the direct actions of caffeine.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.1-6
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• 2005

Stick type ignition coil is new development that connect directly with ECU(Electronic control unit), without needing a spark plug cable and distributor. Glass-fiber reinforced ploymeric composites provide the desirable properties of high stiffness and strength as well as low specific weight. Stick type ignition coil jacket is using PBT CF30 resin. PBT CF30 resin is a kind of electric insulation which is a superior engineering plastic that is used to prevent the leakage of the electrical current. If PET receive a mistake of design or excessive force when HV terminal oppress on jacket, it can happen to crack. Local stress concentrations occurring on the contact surface, the contact phenomenon becomes a direct cause to the wear and failure of mechanical structures. When it is cracked, it can allow a leakage of the electrical current. So, in this study, we analyze the contact stress to PBT jacket using ANSYS program, when HV terminal oppress on jacket. We suppose PBT to be Jacket and we analyzed contact stress that happens in PET like PBT analysis method. We compared the use of PBT and PET.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.6
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• pp.2949-2963
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• 2019

A novel distributed compress-and-forward (CF) system based on multi-relay network is presented. In this system, as the direct link between the source and destination is invalid due to some reasons, such as the limited power, special working environment, or even economic factors, relays are employed to receive analog signals and carry on distributed compressed encoding. Subsequently, the digital signals are transmitted to the destination via wireless channel. Moreover, a theoretical analysis for the system is provided by utilizing the Chief Executive Officer (CEO) theory and Shannon channel capacity theory, and the rate-distortion function as well as the connection between the transmission rate and the channel capacity are constructed. In addition, an optimal signal-to-noise ratio (SNR) -based power allocation method is proposed to maximize the quantization SNR under the limited total power. Simulation result shows that the proposed CF system outperforms the amplify-and-forward (AF) system versus the SNR performance.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.111-111
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• 2022

According to data from the Ministry of Environment, food waste accounted for 27% of the nation5 s household waste in 2020, and 4.67 million tons of food waste is being discharged per year. According to the Food Waste Direct Landfill Prohibition Act, food waste must be incinerated, composted, fodder, and decomposed before landfilling. The cost of incineration and landfilling of food waste is considerable. Therefore, through the process of turning food waste into fertilizer, we are going to investigate the limit of crop application and the change in the growth of crops during continuous use of food waste fertilizer. This study investigated the growth of lettuce such as shoot length, root length, leaf number, fresh weight, and dry weight after treating lettuce with food waste dry powder mixed fertilizer. The experiment was carried out continuously in 2021 (1st year) and 2022 (2nd year), and the treatment groups were set to No Treatment (NT), Chemical Fertilizer (CF), Mixed Fertilizer (MF×1), and Mixed Fertilizer×2 (MF×2), was repeated 3 times. As a result of the 1st year growth survey, there was no significant difference between NT and CF in the case of shoot length, but MF×1 and MF×2 were significantly decreased compared to NT. Root length was not significantly different in all treatment groups. As for the leaf number, there was no significant difference between NT and MF×1, but CF and MF×2 were significantly decreased compared to NT. In fresh weight, MF×1 and MF×2 were significantly decreased compared to NT, and in the case of dry weight, there was no significant difference between NT, MF×1, and MF×2. As a result of the 2nd year growth survey, there was a significant difference in CF and MF×2 in leaf number, but there was no significant difference in all treatment groups with respect to shoot length, root length, fresh weight, and dry weight. Through continuous additional research, it is necessary to confirm the change in soil composition and the growth of crops due to food waste fertilizer treatment.

• Nuclear Engineering and Technology
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• v.53 no.11
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• pp.3784-3789
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• 2021

We report a simple technique for direct neutron spectroscopy using pure LaCl₃ crystals. Pure LaCl₃ crystals exhibit considerably better pulse shape discrimination (PSD) capabilities with relatively good energy resolution as compared with Ce-doped LaCl₃ crystals. Single crystals of pure and Ce-doped LaCl₃ were grown using an inhouse-developed Bridgman furnace. PSD capabilities of these crystals were investigated using ²⁴¹Am and ¹³⁷Cs sources. Fast neutron detection was tested using a²⁵²Cf source and three separate bands corresponding to electron, proton, and alpha were observed. The proton band induced by the ³⁵Cl(n,p)³⁵S reaction can be used for direct neutron spectroscopy because proton energy is proportional to incident neutron energy. Owing to good scintillation performance and excellent PSD capabilities, pure LaCl₃ is a promising candidate for space detectors and other applications that necessitate gamma/fast neutron discrimination capability.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.94-97
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• 1989

It is shown that fundamental plasma characteristic, which are sheath voltage and ion concentration, can be derived from measuring RF impedence. Plasma characteristics from this simple method are verified by direct measuring, to be reasonable. Using these values a new relation between isotropy and the ratio of sheath voltage to ion concentration is derived. For etch in which $CF_4$ is used, anisotropic etch can be achieved in its order $10^{-12}Vcm^3$ and isotropic etch in $10^{-12}Vcm^3$. These results are useful in every asymetric diode type etch system.

• Journal of Radiation Protection and Research
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• v.26 no.3
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• pp.243-248
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• 2001

Neutron reference fields of Korea Atomic Energy Research Institute (KAERI) for calibrating neutron measuring devices to be used in radiation workplace monitoring consist of two kinds of neutron spectra, the direct and the scattered neutron fields, which are produced by using radionuclide neutron sources, 252Cf and 241AmBe sources. Necessary parameters for calibration such as the anisotropy factor of each neutron source and the room-scattered fraction of some neutron surveymeters in the KAERI calibration facility were determined by calculation or measurement. Spectral measurement of scattered neutron fields were performed at each reference calibration point using a Bonner Multi-sphere Spectrometer (BMS) and the dosimetric quantities for calibration also estimated from the neutron energy spectra which were unfolded using the BUNKI code.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.198.1-198.1
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• 2010

The goal of this study is to measure and compare the performance of solar heat pump for room and hot water heating. To accomplish the goal, solar heat pump with alumium roll bond type evaporator and indoor heat exchanger(condenser) was built and fully instrumented with thermocouples and pressure transducers etc. The test results showed that the COP(coefficient of performance) of HFC-134a($CF_3CH_2F$) were higher than those of CFC-12($CF_2Cl_2$). One "stratospherically safe" new refrigerant is 1,1,1,2-tetrafluoroethane(HFC-134a), which is thermodynamically similar to CFC-12 and considered to be a potential direct replacement for CFC-12 in air-conditioning and refrigeration applications. The solar heat pump system for room heating was designed to show the best efficiency that the room temperature make $18{\sim}20^{\circ}C$ and $23{\sim}25^{\circ}C$ in the southern part of South Korea during November, December, and January.