• Journal of the Korean Society for information Management
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• v.5 no.1
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• pp.31-52
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• 1988

The information policy in Japan have bccir growing rapldlr 111 recent vttars. \'arioi~s level of govc~riimerital organrzatlons, ir~bt~tution arid agrircics have undt~rtak~~rr iriforrnatiori polrcy 111 order to i r l - crease information flow toward tlie society in Japan. At tlie same trme, computerized library systems also h a w uridergoirc rapid expansion. NACSIS(National Ceriter for- Science Informat~on System) wl~icl~ was cstablisl~ed bv Mirristr> of Etlr~c~arion, Sc~ence arid Culture haw witnessed dramatic adv;rnces i r i promoting for corrstructiori of database so as to provide their 11rf'3r.mat1orr nu nationwide scale. T l r i h articlr inrroduccs tlie actr\rtle> and ~mplcmeritat~o~~ of it format in^^ pol~cy wl~i(~li taktas a place hy goverrirnrlit of Japar~ aid arraly~c,.; thi~ ~ I . O I . P S I of deciiioii maltiiig iri polit~cal procedures. So far as b:ast-A\~ari riatioris art, ~ . n r i v t ~ r ~ ~ , e.;pc,ciall\. Kr,rc.an a~rd Japair !rave ,imilar cultural and liistorical backjir. ourii1, ard could t)t. tliif most a p p r o p r i a t ~ ~ caac stlldh for political ~nq~lerncritat~orr. Thus the topic of this artrclc will be useful to r t ~ a l l ~ t . Ore, trail ur~d c r r o r prorex, iri iiiior.matior~ pnlic\ulcorner.

• Membrane Journal
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• v.4 no.4
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• pp.221-231
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• 1994

The GR51PP(MWCO 50,000) and GR40PP(MWCO 100,000) membranes manufactured by DDS were used in ultrafiltration of dextran(Mw. : 500,000) solution in flat plate ultrafiltration cell filled with various types of turbulence promoters. The flux improvement by using turbulence promoter was higher in laminar flow region than in turbulent flow region. The maximum improvements of permeate flux were foud as 112% and 50% I laminar flow region and turbulent flow region, respectively. Also, the solute rejection of the ultrafiltration membrane was improved by turbulence promoters and its effect was significant in the high transmembrane pressure and laminar flow region. The smaller the spacer mesh size was used, the higher the flux improved, but the pressure drop in ultrafiltration cell also increased. In laminar flow region, pressure drop by the spacer was negligible, but in turbulent flow region it changed significantly depending upon the mesh size of the spacer and therefore, its mesh size must be baken into account in the design of the process. The predicted results of the modified mass transfer correlation had better agreement with experimental results than those of unmodified one, The modified mass transfer correlations for laminar and turbulent flow region are shown as follow. $N_{sh}=0.151(N_{Re})^{0.199}(N_{Sc})^{0.22}(N_{Scm})^{0.197}\;(625 $N_{sh}=0.0165(N_{Re})^{0.428}(N_{Sc})^{0.33}(N_{Scm})^{0.223}\;(5015

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.2
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• pp.151-160
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• 2022

The sorption of Eu on MX-80 bentonite in Na-Ca-Cl solutions is investigated at a molal proton concentration (pH_m) range of 3 to 10 and an ionic strength (I) range of 0.1 to 6 m (mol·kgw^-1). The sorption equilibrium of Eu on MX-80 is achieved within 14 to 21 d at I = 0.1 and 6 m. The sorption distribution coefficient (K_d) values of Eu for MX-80 increase as pH_m increases from 3 to 6 for all I values, and they are independent of pH_m between 8 and 10 at I ≥ 0.5 m. Meanwhile, at I = 0.1 m, the K_d value at pH_m = 10 is slightly lower than those at pH_m = 8 and 9. The K_d values are not affected by the I values between 0.5 m and 6 m, whereas the K_d value at I = 0.1 m is greater than those at I ≥ 0.5 m, except at pH_m = 10. A two-site protolysis nonelectrostatic surface complexation and cation exchange sorption model is applied to the Eu sorption data for I ≤ 4 m, and the equilibrium constants of the sorption reactions are estimated.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.5
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• pp.258-270
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• 2014

In this paper, we investigate channel capacity of two kinds of uplink OFDMA (Orthogonal Frequency Division Multiple Access) schemes, i.e. ZCZ (Zero Correlation Zone) code time-spread OFDMA and sparse SC-FDMA (Single Carrier Frequency Division Mmultiple Access) robust to access timing offset (TO) among multiple users. In order to reflect the practical condition, we consider not only access TO among multiple users but also peak to average power ratio (PAPR) which is one of hot issues of uplink OFDMA. In the case with access TO among multiple users, the amplified signal of users by power control might affect a severe interference to signals of other users. Meanwhile, amplified signal by considering distance between user and base station might be distorted due to the limit of amplifier and thus the performance might degrade. In order to achieve the maximum channel capacity, we investigate the combinations of transmit power so called ASF (adaptive scaling factor) by numerical simulations. We check that the channel capacity of the case with ASF increases compared to the case with considering only distance i.e. ASF=1. From the simulation results, In the case of high signal to noise ratio (SNR), ZCZ code time-spread OFDMA achieves higher channel capacity compared to sparse block SC-FDMA. On the other hand, in the case of low SNR, the sparse block SC-FDMA achieves better performance compared to ZCZ time-spread OFDMA.

• Journal of Sensor Science and Technology
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• v.6 no.5
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• pp.407-413
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• 1997

The crystallized CuPc(copper phthalocyanine) film on a p-type <100> Si substrate is prepared at the substrate temperature of $300^{\circ}C$ by thermal evaporation. X -ray diffraction analysis showed the CuPc film to have a-axis oriented structure. For the measurement of photovoltaic characteristics of the CuPc/Si film and the Si substrate, a transverse current-voltage (I-V) curve is observed. In the dark, the Au/Si junction is shown to be ohmic contact. However, under illumination, a photovoltaic effect is not observed. The I-V curve in the dark indicates that the CuPc film on Si may form an ohmic contact. Since the CuPc film is a p-type semiconductor, the CuPc/p-Si junction has no barrier at the interface. Under illumination, the CuPc/Si junction shows a large photocurrent comparing with that of the wafer. The result indicates that the CuPc layer plays an important role in the photocarrier generation under red illumination (600 nm). The CuPc/Si film shows the photo voltaic characteristics with a short-circuit photocurrent ($J_{sc}$) of $4.29\;mA/cm^{2}$ and an open-circuit voltage ($V_{oc}$) of 12 mA.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.538-543
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• 2018

Powdery mildew caused by Podosphaera xanthii is a disease in cucurbit crops especially in green house. The objective of this study was to determine the effect of alternative fungicide spraying system for control of powdery mildew disease. We selected four fungicides with different mode of action and made three treatment combinations of each fungicide in 2017. Pyraclostrobin-flutianyl-penthiopyrad treatment showed the highest control value (87%) while, pyraclostrobin-pyraclostrobin-pyraclostrobin treatment showed the lowest control value (32.5%). So it seemed like the treatment was not suitable for control of powdery mildew. In 2018, pyraclostrobin of pyraclostrobin-flutianyl-penthiopyrad was replaced to contact fungicide called iminoctadine-tris-albesilate and compared control effect of two treatments. Two of the treatments showed similar control value (87.0% for pyraclostrobin, 89.0% for iminoctadine-tris-albesilate). These two tests in 2017 and 2018 indicated that alternative treatment of different fungicides is essential for controlling of powdery mildew and inhibiting development of fungicide resistance.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.44 no.4 s.316
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• pp.35-41
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• 2007

In this paper a single-wheeled robot called GYROBO is built and its hardware is implemented. The single-wheeled robot is similar to a rolling disk relying on gyroscopic motions to maintain its balance. The GYROBO consists of three actuators: a spin motor a tilt motor, and a drive motor. The spin motor spins a flywheel at a high rate so that it provides the balancing stability to upright the robot. The tilt motor controls steering of the robot by gyroscopic effect. The drive motor makes forward accelerated motion to the robot. Several models are designed. Experimental works of the GYROBO to turn and move forward have been presented.

• Journal of Oriental Neuropsychiatry
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• v.29 no.4
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• pp.231-238
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• 2018

Objectives: To evaluate the psychological characteristics of Korean medical students focusing on the Holland types and the MMPI-2. Methods: A survey was conducted on 81 Korean medicine students to investigate psychological characteristics focusing on the Holland types and the MMPI-2. Results: The orders of frequency of the Holland type in Korean medicine students were S>I>C>A=E>R (all), I>S>C>R=E>A (male) and S>A>C>I>E>R (female). The relationships between the Holland types and the MMPI-2 were R type (Mf negative), A type (Mf Pa Ma positive, Si negative), S type (Mf positive, D Pt Sc Si negative) and E type (Ma positive, D Si negative). Conclusions: From personality tests for male and female Korean medical students, there were differences on some scales of the Holland types. The Holland types are related to the specific scales of the MMPI-2.

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.179-186
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• 2006

Two types of $TiO_2$, nanotube and nanoparticle, were used for the mesoporous coatings by doctor blade technique followed by calcining at $450^{\circ}C$. The coatings were used as working materials for dye-sensitized solar cells (DSCs) later on and their photovoltaic characterization was carried out. The nanoparticle was synthesized from hydrogen titanate nanotube by hydrothermal treatment at $180^{\circ}C$ for 24 hr. The solar energy conversion efficiency (${\eta}$) of DSCs prepared by this nanoparticle reached 8.07％ with $V_{OC}$ (open-circuit potential) of 0.81 V, $I_{SC}$ (short-circuit current) of $18.29mV/cm^2$, and FF (fill factor) of 66.95％, respectively. For the preparation of nanotube, the concentration of NaOH solution varied from 3 M to 5 M. In the case of DSCs fabricated with nanotubes from 3 M NaOH solution, the ${\eta}$ reached 6.19％ with $V_{OC}$ of 0.77 V, $I_{SC}$ of $12.41mV/cm^2$, and FF of 64.49％, respectively. On the other hand, in the case of 5 M solution, the photovoltaic ${\eta}$ was decreased with 4.09％ due to a loss of photocarriers. In conclusion, it is demonstrated that the solar energy conversion efficiency of DSCs made from $TiO_2$ nanoparticle showed best results among those under investigation.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.4B no.2
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• pp.86-91
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• 2004

PV power generation, which directly converts solar radiation into electricity, contains numerous significant advantages. It is inexhaustible and pollution-free, silent, contains no rotating parts, and has size-independent electricity conversion efficiency. The positive environmental effect of photovoltaics is that it replaces the more polluting methods of electricity generation or that it provides electricity where none was available before. This paper highlights a novel simple method to abstract the entire parameters of the solar cell. In development, design and operation of PV power generation systems, a technique for constructing V-I curves under different levels of solar irradiance and cell temperature conditions using basic characteristic values of the PV module is required. Everyone who has performed manual acquisition and analysis of solar cell I versus V data would agree that the job is tedious and time-consuming. A better alternative is to use an automated curve tracer to print out the I versus V curves and compute the four major parameters; $V_{oc}$, $I_{sc}$, FF, and . Generally, the V-I curve tracer indicates only the commonly used solar cell parameters. However, with the conventional V-I curve tracer it is almost impossible to abstract the more detailed parameters of the solar cell; A, $R_{s}$ and $R_{sh}$ , which satisfies the user, who aims at the analysis of the development of the PV power generation system, that being advanced simulation. In this paper, the proposed method provides us with satisfactory results to enable us to abstract the detailed parameters of the solar cell; A, $R_s$ and $R_{sh}$.>.