• KSBB Journal
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• v.6 no.3
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• pp.309-319
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• 1991

A continuous stirred tank membrane reactor(CSTMR ) was developed and optimized for the production of cod skin gelatin hydrolyzates using endo-protease Alcalase. A experimental design methodology was used to optimize the four performance variables: enzyme concentration, substrate concentration, permeate flux and reactor volume. All four variables studied had an effect on substrate conversion, with enzyme and substrate concentrations being predominant. Conversion increased with the increase in enzyme concentration, with the decrease in substrate concentration, at high volumes and low flux. A strong interaction was observed between enzyme and substrate concentrations and smaller interactions between enzyme and flux and substrate and flux. The optimum operating conditions for the CSTMR process for an initial substrate concentration for 10% were $50^{\circ}C$, pH 8, flux 7.3ml/min, residence time 82 min, and Alcalase to substrate ratio 0.02(w/w). A gradual decay in reactor activity during 8 hrs was 2.1% conversion/hr. Enzyme leakage through the 10, 000 MWCO membrane was 16% at $50^{\circ}C$ and 12% at $35^{\circ}C$, 6hrs. However, there was no apparent correlation between enayme leakage and substrate conversion. The Km value for the CSTMR was 20 times higher than the batch reactor. The productivity(expressed as mg product/mg enzyme) of the CSTMR was more than six fold higher than the batch at $50^{\circ}C$. The hydrolyzate was non-bitter.

• Journal of the Korean Vacuum Society
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• v.10 no.3
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• pp.380-386
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• 2001

A nuclear microprobe system with adjustable precision object slits and a magnetic quadrupole doublet was designed by the beam optics simulation using a first order matrix formalism, and installed in a $30^{\circ}$ beam line connected with KIGAM 1.7 MV Tandem VDG Accelerator. Demagnification factors for x and y axis are calculated to be 25 and 4.9, respectively, and a minimum beam spot side is expected to be about 5 $\mu\textrm{m}$ for 3 MeV proton beams with a current of about 1 nA. A multi-purpose octagonal target chamber has been built to facilitate MeV ion-beam analytical techniques of PIXE, RBS, ERDA, and ion beam micro-machining. It contains X-ray and particle detectors, a zoom microscope, a Faraday cup, a 4-axis sample manipulator and a high vacuum pumping system. The system performance of the nuclear microprobe is now being tested, and automatic manipulator control and data acquisition system will be installed for routine applications of micro ion-beam analytical techniques.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.3
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• pp.292-298
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• 2016

In this research, considering the practical situation of separated placing method for mass concrete structure, an efficient method of controlling the heat of hydration is suggested by comparing between the simulated values and actual measurements conducted with the optimum mix design obtained from the various mix conditions with different types and amount of supplementary cementitious materials(SCMs). As the result of the research, firstly, the optimum mix designs for top and bottom layers were determined by Midas gen as OPC to FA of 85 to 15, and OPC to FA to BS of 50 to 20 to 30, respectively. The concrete mixtures prepared with the mix designs determined from the simulation satisfied the target performance range in slump, air content and compressive strength. Additionally, from temperature measurement for the actual mass concrete placed during spring, the maximum temperature difference between surface and core was about $10^{\circ}C$ with 59 and $49^{\circ}C$ for top and bottom layers, respectively, and 1.4 of cracking index was obtained. Therefore, considering the practical conditions of mass concrete construction, it is considered that the different heat of hydration method using different mix designs with SCMs can be an efficient method for controlling thermal cracking and settling cracking of mass concrete.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.4
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• pp.397-403
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• 2008

In this paper, the mixer was implemented in the non-radiative dielectric waveguide that is the main component of 60 GHz band radio telecommunications equipment which a demand increases for the purpose of point-to-point communication network. As to the manufacture of the non-radiative dielectric waveguide mixer, it was the implementation of the dielectric line combiner to be most difficult. The thing which that gives shape to the curvature which is the dielectric line determined and the to place in the exact interval thing are easy. For this reason, it was very difficult to make in order to have the regular performance in the case of the mixer having the dielectric line combiner. In this paper, since the dielectric line combiner was replaced with the waveguide directional coupler and the manufacture was possible through a processing it had the characteristic that a combiner is fixed. In result, the productivity of a mixer was innovatively improved. The design frequency of the mixer implemented through this paper RF and LO are $51{\sim}64\;GHz$. IF Is $DC{\sim}\;GHz2$. The down conversion loss toward the RF input of $60{\sim}62\;GHz$ was measured by $10{\pm}1\;dB$ in the condition that LO is 10 dBm, 60 GHz.

• Korean Journal of Clinical Pharmacy
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• v.15 no.1
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• pp.21-26
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• 2005

A bioequivalence study of CKD $Cefaclor^{(R)}$ capsule (Chong Kun Dang Pharm Co., Ltd) to $Ceclor^{(R)}$ capsule (Lilly Korea Co., Ltd.) was conducted according to the guidelines of Korea Food and Drug Administration (KFDA). Twenty four healthy male Korean volunteers received each medicine at the cefaclor dose of 250 mg in a $2{\times}2$ crossover study. There was a one-week washout period between the doses. An improved high-performance liquid chromatorgraphy (HPLC) analytical method with UV detection was used to determine plasma cefaclor concentration in human volunteers for 8 hr after oral drug administration. The area under the plasma concentration-time curve from time zero to 8 hr ($AUC_{0-8hr}$) was calculated by the linear trapezoidal rule. the $C_{max}$ (maximum plasma drug concentration) and $T_{max}$ (time to reach $C_{max}$) were compiled from the plasma concentration-time data. Analysis of variance was carried out using logarithmically transformed $AUC_{0-8hr}\;and\;C_{max}$. No significant sequence effect was found for all of the bioavailability parameters indicating that the cross-over design was properly performed. The $90{\%}$ confidence intervals of the $AUC_{0-8hr}$ ratio and the $C_{max}$ ratio for CKD $Cefaclor^{(R)}$ and $Ceclor^{(R)}$ were $0.9400{\leq}{\delta}{\leq}1.0345$ and $0.8858{\leq}{\delta}{\leq}1.1021$, respectively. These values were within the acceptable bioequivalence intervals of 0.80-1.25. Thus, our study demonstrated the of CKD $cefaclor^{(R)}$ capsule was bioequivalent to $Cefaclor^{(R)}$ capsule with respect to its bioavailability.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.1
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• pp.8-14
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• 2017

Due to the financial crisis in 2008, the world economy collapsed leading to an increase in oil prices and a decrease in freight by shipping. To overcome this crisis, major shipping companies ordered larger ships, changed their trading route and improved operating of ships to overcome deficits. In particular, low-speed navigation was much favored by many companies so that it can reduce fuel consumption. However, the long-term operation of high-speed optimized engines in low-speeds has affected the jacket cooling fresh water (J.C.F.W.) system as they fail to maintain the normal operational temperature. The temperature of J.C.F.W. system dropped leading to low temperature corrosion. As a result, when the engine is operating at minimal load the functioning of existing J.C.F.W cooler is decreased and the use of fresh water generator is substantially limited. Therefore, an improvement in the functioning of J.C.F.W. system is necessary. In this paper, in order to review the improvements required for the operation of J.C.F.W. of low-speed operating marine diesel, an experiment was conducted by comparing and analyzing the results of the main engine J.C.F.W. system of a Panamax class bulk carrier 82k and a Cape class bulk carrier 180k by installing and uninstalling the J.C.F.W. Cooler. Thus, this paper proposed an improved design of the J.C.F.W. system that is suitable for the present low-speed operation.

• Korean Journal of Digital Imaging in Medicine
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• v.14 no.1
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• pp.13-20
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• 2012

In a normal x-ray examination, the cooperation of a patient in positioning greatly influences the improvement of work performance, the quality of the images and the reduction in time spent on the examination. An attempt was made to discover the connection between an examination information printout and the effects of the examination by informing the patient before the examination on the examination positions in order to increase the level of cooperation by the patient and by surveying the degree of satisfaction of the patient during the examination proceedings. An examination information printout was prepared on five positions that patients consider to be difficult while receiving normal x-ray examinations and were shown to 257 male and female patients between the ages of 30 to 79 who had visited this hospital between January 1 to February 29, 2012 or to a person who had accompanied the patients before the examination to research the degree of satisfaction regarding the printout. In addition, the examination explanation printout was given to Radiologic Technologists with over 1 year experience in this hospital to use while taking the x-rays and the degree of satisfaction was surveyed and it was examined if the increase of the degree of satisfaction had an effect on the reduction in the examination time. The patients who utilized the examination information printout revealed results of approximately a 7.8% higher degree of satisfaction among the patients who had previous experience receiving x-ray examinations compared to those were having an x-ray for the first time. In the age groups between 30 to 70 years of age, the age group in the 30's revealed the lowest level of satisfaction at approximately 69% and the group in the 50's showed the highest degree of satisfaction of 87.94%. In the survey of the Radiologic Technologists, 85% responded that they were satisfied. In the question that stated "Will the examination information printouts reduce the time involved in unnecessary conversations with the patients?," the responses showed a 95% degree of satisfaction. The degree of satisfaction was high over the examination information printout by both the patients and the Radiologic Technologists. Although the effects of examination time reduction varied based on the ages of the patients and physical conditions that they were in and could not be given measurement values, it was able to be seen through the survey that reduction of the unnecessary communication between the patient and the Radiologic Technologists contributed to the increase in the degree of satisfaction. As a result, both the patients and the Radiologic Technologists had an increased degree of satisfaction over the examination information printout and it was possible for improvements to be made in the quality of medical service provided as well. Nevertheless, it is considered that a more developed manual in terms of quality and quantity must be produced using a more systematic approach and design.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.497-507
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• 2009

The principal objective of this study was to assess the situation of foodservice facilities, utilities, and physical environment in the Chonbuk area. Self-administered questionnaires were collected from 252 nutrition teachers and school dietitians. Statistical data analysis was completed using the SPSS v. 11.5 program. The results were summarized as follows: Approximately 99.2% of the subjects were women 76.6% were married, over 87% were between the ages of 30 and 40(p<0.01) and 56.8% had more than 11 years of experience(p<0.001). Among the 252 school foodservice systems evaluated, 51.6% of the schools were located in urban areas and 48.0% were in rural areas(p<0.01). Approximately 68.0% of the schools prepared meals in the conventional way, and 32.3% prepared them in the commissary way(p<0.001). The number of employees at each institution was separated into the following categories: 1 to 3(37.7%), 4 to 6(27.8%), and 7 to 9(25.4%, p<0.01). Approximately 54.0% of schools had been running a school meal service for longer than 11 years(p<0.001). However, 67.5% of those facilities had not been remodeled since the initial implementation of foodservices. Approximately 94.0% of the school foodservice facilities were located on the first floor. 72.2% among them were constructed of reinforced concrete and 16.7% were prefabricated(p<0.001). As the result of our evaluation of related physical evidence and the atmosphere of the space, the average importance grade was $4.41{\pm}0.46$, and the average performance grade was $2.78{\pm}0.67$. Most nutrition teachers and school dietitians in elementary, middle, & high schools responded that the related physical evidence and the atmosphere of the space in school foodservice facilities were important, but the satisfaction level among the nutrition teachers and school dietitians was quite low. Therefore, it's important and necessary to analyze the opinions of the stakeholders in the foodservice industry prior to the remodeling of school foodservice facilities and utilities.

• Journal of Korean Society of Steel Construction
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• v.29 no.3
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• pp.249-260
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• 2017

In order to investigate the structural performance of a novel prefabricated-SRC column using bolt-connected steel angles(PSRC column), eccentric axial loading tests were performed for six PSRC column specimens and two conventional SRC column specimens. The test parameters were the spacing and sectional configurations of lateral reinforcement, and eccentricity ratio of axial load. The test results showed that, due to high axial-stiffness of the angles located at the corners of the cross section, the compressive load-carrying capacity and deformation capacity of the PSRC specimens were greater than those of the SRC specimens in the large eccentricity ratio of axial load. Closely spaced lateral steel plates and Z-shaped lateral steel plates improved lateral confinement, which increased the load-carrying capacity of the PSRC specimens. The combined flexural and axial load-carrying capacity of the specimens by tests and nonlinear numerical analysis were greater than the predictions by current design codes. The numerical analysis agreed well with the test results including the initial stiffness, peak strength, and post-peak strength degradation.

• Journal of Wetlands Research
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• v.15 no.2
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• pp.215-222
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• 2013

In this study, the nutrient concentration changes along the hydrologic flow path of a free water surface flow constructed wetland (CW) treating agricultural stream runoff was investigated. Dry sampling was performed from April 2009 to November 2011 at five locations representing each treatment units of the CW. Grab water samples were analyzed for nitrogen forms such as total nitrogen (TN), total Kjeldahl nitrogen, nitrate, and ammonium; and phosphorus forms including total phosphorus (TP) and phosphate. Findings revealed that the physical properties such as temperature, dissolved oxygen and pH affected the TP retention in the CW. High nutrient reduction was observed after passing the first sedimentation zone indicating the importance of settling process in the retention of nutrients. However, it was until the 85% of the length of the CW where nutrient retention was greatest indicating the deposition of nutrients at the alternating shallow and deep marshes. TN and TP concentration seemed to increase at the final sedimentation zone (FSZ) suggesting a possible nutrient source in this segment of the CW. It was therefore recommended to reduce or possibly remove the FSZ in the CW for an optimum performance, smaller spatial allocation and lesser construction expenses for similar systems.