• Journal of the Korean Dietetic Association
• /
• v.12 no.4
• /
• pp.404-410
• /
• 2006

This study was done to analyze the contents of food and nutrition information sites on the internet. In analysis, 276 web sites were used. Web sites from 3 internet search engines(Yahoo, Empas, Naver) were selected on the date of July 15th, 2004. The trained panels evaluated web sites' contents by the assessment tools using 3-point scale(2:strongly agree, 1:agree, 0:disagree). The contents classified by topics were functional foods(46.4%), cuisine and cooking(38.4%), food sanitation and safety(30.4%) and so on. Operators of web sites were individual(35.9%), company(30.4%) and public institution(33.7%). About 89.5% of web sites were operated for unspecified people. Contents of the web sites were well established especially in consistency in title and contents(1.6), scientific basis of explanations(1.2) and benefit of information(1.2) and so on while not well established in providing relevant sites(0.7), providing contact address and feed back mechanism(0.7) and so on. Web sites operated by public institutions are rated significantly higher than web sites operated by individual or company. In conclusion, in order to qualitatively improve food and nutrition information on the internet, continuing monitoring and evaluation are highly required and web sites operated by public institutions shall be developed further.

• Polymer(Korea)
• /
• v.33 no.3
• /
• pp.198-202
• /
• 2009

Oligo(ethylene terephthalate)(OET), oligo(ethylene succinate-co-terephthalate)(OEST) and oligo(butylene succinate-co-terephthalate)(OBST), which are part of the poly(ethylene terephthalate)(PET) oligomer, were synthesized. Degradation test of oligomers carried out by the presence of lipase PS. There were two objectives in the experiment: first, to measure the weight remaining of the PET oligomer as increasing degradation time, and second to examine the degradation mechanism by analyzing the resulting degraded product. In the synthesis of OEST and OBST, by controlling the feed ratio of both OEST and OBST, we were able to obtain oligomer of different composition ratios. The various composition ratios resulted in oligomer of vastly different thermal properties. We observed that both OEST and OBST were degraded using lipase PS, but as the composition of terephthalic acid was increased, the lipase PS became less effective. We confirmed that the lipase PS easily decomposed polyester of the aliphatic compound.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.4 no.3
• /
• pp.55-63
• /
• 2000

Studies for tube spin forming have been implemented restrictively compared to spinning process, because of the complex of deformation mechanism. Especially there were not many studies by using FEM(Finite Element Method) for overcoming restriction of upper bound method. In this paper, the tube spinning process is analyzed to produce cylindrical body made by titanium alloy. In analysis, processing parameters was obtained by using upper bound method to consider material properties of titanium alloy and finite element analysis was implemented to investigate the flatness and the elongation of the titanium alloy workpiece by using ABAQUS code. The independent variables are ; material properties of workpiece, angles of roller, reduction of diameter. Three variables, two angles of roller and reduction of diameter are optimized by using the upper bound method. In this method, we can estimate the workable power, working force and reduction of diameter, and also the flatness and the elongation of workpiece by the finite elements analysis using ABAQUS/standard. The results indicates that these variables play a critical factors of spinning process for the titanium alloy and the optimum values of these variables.

• Journal of electromagnetic engineering and science
• /
• v.18 no.2
• /
• pp.117-128
• /
• 2018

In this paper, compact linear dual polarized series-fed $1{\times}2$ linear and $2{\times}2$ planar arrays antennas for airborne SAR applications are proposed. The proposed antenna design consists of a square radiating patch that is placed on top of the substrate, a quarter wave transformer and $50-{\Omega}$ matched transformer. Matching between a radiating patch and the $50-{\Omega}$ microstrip line is accomplished through a direct coupled-feed technique with the help of an impedance inverter (${\lambda}/4$ impedance transformer) placed at both horizontal and vertical planes, in the case of the $2{\times}2$ planar array. The overall size for the prototype-1 and prototype-2 fabricated antennas are $1.9305{\times}0.9652{\times}0.05106{{\lambda}_0}^3$ and $1.9305{\times}1.9305{\times}0.05106{{\lambda}_0}^3$, respectively. The fabricated structure has been tested, and the experimental results are similar to the simulated ones. The CST MWS simulated and vector network analyzer measured reflection coefficient ($S_{11}$) results were compared, and they indicate that the proposed antenna prototype-1 yields the impedance bandwidth >140 MHz (9.56-9.72 GHz) defined by $S_{11}$<-10 dB with 1.43%, and $S_{21}$<-25 dB in the case of prototype-2 (9.58-9.74 GHz, $S_{11}$< -10 dB) >140 MHz for all the individual ports. The surface currents and the E- and H-field distributions were studied for a better understanding of the polarization mechanism. The measured results of the proposed dual polarized antenna were in accordance with the simulated analysis and showed good performance of the S-parameters and radiation patterns (co-pol and cross-pol), gain, efficiency, front-to-back ratio, half-power beam width) at the resonant frequency. With these features and its compact size, the proposed antenna will be suitable for X-band airborne synthetic aperture radar applications.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.13 no.4
• /
• pp.604-610
• /
• 1989

This paper is concerned with the machinability of fine ceramics(Al$_{2}$O$_{3}$) by using sintered diamond tools. For this purpose, ceramics cutting experiments under various cutting conditions such as cutting speed, feed rate, and others were carried out. The main results are follows : (1) During the cutting of fine ceramics, the used tools were found to be slightly chattering at cutting speed of 70m/min, and at cutting speed of higher than this I found the fine ceramics difficult to be cut. (2) When I used a tool with large nose radius, there occured a small amount of wear on the flank of the tool. However, at the early stage of fine ceramics cutting, the tools with smaller nose radii were required mainly to prevent the chipping of the ceramics. (3) When the materials were dry-cut, the appropriate cutting speel was found to be lower than 40m/min, and when the materials were dry-cut, I could cut them without any difficulty even at the speed of 70m/min, the surface roughness of ceramics cut at the speed of 70m/min was considerly fine. (4) It is generally believed that the principal cutting force is the largest in the case of steels cutting, but I found the thrust cutting force to be larger than any other cutting forces in the case of ceramics cutting.

• The Journal of Korean Medical History
• /
• v.18 no.1
• /
• pp.3-14
• /
• 2005

Among modern people's life-style, the lack of exercise and sleep is related to infertility. Underexercise accumulates damp-sputum, resulting in the insufficiency of essence. It also obstructs the creation of essence, leading to insufficient essence. Activities at night without sleep cannot create the condition to help the process of yin, causing the insufficiency of essence. Fast food is made from the cattle which are fed the feed containing growth hormone and antibiotics in large quantities. Growth hormone causes the process of yang excessively in human body, while antibiotic suppresses the process of yin, leading to excessive damp-heat and hyperactive ministerial fire. Antiseptic included in instant food hampers the process of fermentation, or yin, and inhibits the digestion mechanism, obstructing damp-heat and bringing about hyperactive ministerial fire. Intake of excessive flesh and meat gives rise to incomplete combustion and hinders the creation of essence, causing hyperactive ministerial fire due to the lack of yin. Milk suits the calf that has a rapid growth cycle. Milk intake by humans leads to the rapid process of yang and eventually hyperactivity of ministerial fire. The imbalance between yin and yang, with essence insufficent and ministerial fire hyperactive, causes infertility in three aspects. First, the lack of essence itself makes conception difficult. Secondly, damp-sputum resulting from ministerial fire obstructs the circulation of qi and blood. It also hampers the normal supply of qi and blood to the uterus. Thirdly, the excessive process of yang may result in infertility. Generally speaking, pregnancy starts with implantation. If the excessive process of yang is in progress in body, static condition needed for implantation cannot be maintained, leading to infertility.

• Journal of Biomedical Engineering Research
• /
• v.25 no.6
• /
• pp.505-510
• /
• 2004

In this article, we present an automated system for adjusting the 6 degree of freedom (D.O.F.) circular fixator. The system includes a scheduling software to adjust the Hexapod Circular Fixator (HCF) and an automated strut with the ability of the multiple synchronized motion and independent motion. The HCF was designed to control a 6 D.O.F. Ilizarov fixator and it's mechanism. The HCF adjustment software evaluates each value of altered length of the HCF struts to correct the complex skeletal deformity by using the X-ray data of the patient. The data of HCF adjustment software feed into the automated strut system which provides the scheduled adjustment. Then, the automated strut is synchronized by input data. Also the data of HCF adjustment software can be used to adjust HCF without automated struts. The proposed HCF system was verified by experiments.

• Journal of Biosystems Engineering
• /
• v.27 no.1
• /
• pp.11-18
• /
• 2002

One of the major obstructing factors against managing dairy farm in Korea has been a shortage of roughage supply, which resulted in excessive abuse of concentrate feed. In order to solve this problem, production of the wrap silage by the winter cereal forages raised in the fallow paddy field is strongly recommended in Korea. The main objective is to develop a tractor attached round bale wrapper which can process the silage by wrapping the round bales with thin plastic films. This is the first half of the study which is divided by two parts. In this first part, bale wrapping process was analyzed, and based on this results the followings were designed, developed and tested. 1. Bale wrapper which haying the maximum capacity of 1 ton bale with various functions such as loading, wrapping, discharging the round bales and supplying and cutting wrap films was designed. 2. An actuator and its hydraulic circuit of each process were developed and tested. 3. Also, the variations of hydraulic pressure and engine speed were investigated by operating bale wrapper developed. In this test, maximum pressure of the hydraulic circuit for the bale wrapping was 130 kg/㎠ when it raised the bale, which was quite below the relief pressure of 170 kg/㎠ of hydraulic circuit. In the engine speed test, speed drop was 20∼67 rpm, which meant that there was no over-load operation. Therefore, the experiment proved that developed hydraulic circuit and mechanism is stable in bale wrapping operation

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.7
• /
• pp.2334-2340
• /
• 2010

Sun position computed by Michalsky shows maximum $1.5^{\circ}$, $0.88^{\circ}$ and 2 minutes differences in azimuth, altitude, and sunrise and sunset times respectively compared with Korean Almanac. The 2-axis solar tracking system, which consist control panel with ATmega128 CPU, BLDC motor-cylinder actuator and 2-axis link mechanism, was developed. Computed azimuth and altitude of sun for a current time, and latitude and longitude of tracker position built are controlled in real time by BLDC motor-cylinder actuators comparing with the position feed-backed by Hall sensor. The use of BLDC motor is free in maintenance. Implementation of a home-return function by Hall sensor is to minimize the cumulative error.

• Korean Journal of Veterinary Service
• /
• v.28 no.2
• /
• pp.91-98
• /
• 2005

Green tea was known which regulated adipocyte differentiation metabolism. The mechanism on the lipid decreased contents of TAG in the plasma. In addition, green tea increased the expression leptin mRNA, PPAR $\delta$ mRNA and TGF $\beta$. The tea tested was korean powdered green tea. In this experiment, Sprague-Dawley (SD) rats were fed $3\%$ green tea(powdered) for 3 weeks on the basal diet and obese diet and green tea grouts-fed pork meats. duck meats. The expression of leptin mRNA and PPAR $\delta$ mRNA were up-regulated in the green tea-fed groups compared with those of the not green tea-fed groups. There were no significantly difference on the expression of leptin mRNA and PPAR $\delta$ mRNA in green tea grouts-fed pork meats, duck meats as compared with the not fed green tea grouts meats. TGF $\beta$ mRNA. TNF $\alpha$ mRNA and adipsin mRNA were not expressed in the pork meats, duck meats. The expression of TGF $\beta$ mRNA, TNF $\alpha$ mRNA and adipsin mRNA were observed in the experimental rats but no significantly difference on the contents. Physiologic regulated genes were not expressed In the green tea grout-fed pork meats and duck meats.