• Journal of the Korean Magnetics Society
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• v.18 no.2
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• pp.75-78
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• 2008

$AB_2X_4$(A, B=Transition Metal, X=O, S, Se) are cubic spinel normal ferrimagnets, in which M ions occupy the tetrahedral sites and Cr ions occupy the octahedral sites. Recently, they have been investigated for behaviour of B site ions and A-B interaction. Polycrystalline $[Co_{0.9}Zn_{0.1}]_A[Cr_{1.98}{^{57}Fe_{0.02}}]_BO_4$ compound was prepared by wet-chemical process. The ferrimagnetic transition was observed around 90K. $M\"{o}ssbauer$ absorption spectra at 4.2K show that the well-developed two sextets are superposed with small difference in hyperfine fields($H_{hf}$). The hyperfine fields of $CoCr_{1.98}{^{57}Fe_{0.02}}O_4$ and $Co_{0.9}Zn_{0.1}Cr_{1.98}{^{57}Fe_{0.02}}O_4$ were determined to be 488, 478 kOe and 486, 468 kOe, respectively. We notice that the one of the magnetic hyperfine field values changes with Zn ion substitution. These results suggest the incommensurate states and spin-reorientation temperature($T_S=18K$) changes with Zn ions substitution below spin-reorientation temperature($T_S=28K$) of $CoCr_{1.98}{^{57}Fe_{0.02}}O_4$

• Korean Journal of Materials Research
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• v.12 no.8
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• pp.624-633
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• 2002

In order to improve the hydrogen storage capacity and the activation properties of the hydrogen storage alloys, the rare-earth metal alloy series, MmN $i_{4.5}$M $n_{0.5}$Z $r_{x}$(x=0, 0.025, 0.05, 0.1), are prepared by adding excess Zr in MmN $i_{4.5}$M $n_{0.5}$ alloy. The various parts in hydrogen storage vessel consisted of copper pipes reached the setting temperature within 4~5 minutes after heat addition, which indicated that storage vessel had a good heat conductivity required in application. The performance test on storage vessel filled with rare-earth metal alloys of 1000 gr was also conducted after hydrogen charging for 10 min at $18^{\circ}C$ under 10 atm. It showed that the average capacity of discharged hydrogen volume was found to be for $MmNi_{4.5}$ $Mn_{0.5}$ and $MmNi_{4.5}$ $Mn_{x}$ 0.5/$Zr_{samples}$ indicated that the released amount of hydrogen for this $AB_{5}$ type alloys was more than 92 % of theoretic value, and also it was found that the optimum discharging temperature for obtaining an appropriate pressure of 3 atm was determined to be $V^{\circ}C$ for $MmNi_{4.5}$ $Mn_{0.5}$$Zr_{x}$(x=0, 0.025, 0.05, 0.1) hydrogen storage alloys. The released amount of these hydrogen storage samples was 125 $\ell$ , 122.4 $\ell$ and 108.15 $\ell$/kg for $MmNi_{4.5}$ $Mn_{0.5}$ $Zr_{0.025}$ $MmNi_{4.5}$M $n_{0.5}$Z $r_{0.05}$, and MmN $i_{4.5}$ Mn_0.5$Zr_{0}$, at $70^{\circ}C$ respectively. Amount of the 2nd phases increase with increase on Zr contents in $MmNi_{4.5}$$Mn_{0.5}$ $Zr_{ 0.1}$/ alloy. This phenomenon indicates that$ ZrNi_3$ in $MmNi_{4.5}$ $Mn_{0.5}$ $Zr_{x}$ / phase, which shows the maximum storage capacity and the strong resistance to intrinsic degradation, is considered as a proper alloy for hydrogen storage. As the Zr contents increase, the activation time and the plateau pressure decreases and sloping of the plateau pressure increases.creases.eases.s.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.529-537
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• 2005

Ssamjang samples were prepared by central composite design for five independent variables, Gochujang mash aging period $(X_1)$, Doenjang aging period $(X_2)$, Doenjang content $(X_3)$, sterilization temperature $(X_4)$ and storage temperature $(X_5)$. Browning characteristics of Ssamjang were analyzed such as water activity, free amino acids, free sugars and color during storage. Water activities of Ssamjang were ranged from 0.605 to 0.666 at the beginning of storage, and were shown to be the highest at the 8th week of storage and then decreased gradually. Among free amino acids the content of glutamic acid was the highest. Proline, leucine, phenylalanine, lysine and serine were slightly higher than the others. Larger amounts of free amino acids and free sugars were observed from the sample sterilized at $60^{\circ}C$ when compared to that at $70^{\circ}C$. Glucose, fructose and maltose as free sugars were identified from Ssamjang and glucose content was the largest among. During the storage, lightness $(L^*)$, redness $(a^*)$ and yellowness $(b^*)$ of Ssamjang were decreased and total color difference $({\Delta}E)$ was increased. The color changes in the sample surface were more affected by temperature of which storage temperature was more influenced than sterilization temperature.

• Journal of the Korean Society of Radiology
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• v.14 no.1
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• pp.39-44
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• 2020

The purpose of this study was learning about chest X-ray image classification and accuracy research through Deep Learning using big data technology with Convolution Neural Network. Normal 1,583 and Pneumonia 4,289 were used in chest X-ray images. The data were classified as train (88.8%), validation (0.2%) and test (11%). Constructed as Convolution Layer, Max pooling layer size 2×2, Flatten layer, and Image Data Generator. The number of filters, filter size, drop out, epoch, batch size, and loss function values were set when the Convolution layer were 3 and 4 respectively. The test data verification results showed that the predicted accuracy was 94.67% when the number of filters was 64-128-128-128, filter size 3×3, drop out 0.25, epoch 5, batch size 15, and loss function RMSprop was 4. In this study, the classification of chest X-ray Normal and Pneumonia was predictable with high accuracy, and it is believed to be of great help not only to chest X-ray images but also to other medical images.

• Resources Recycling
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• v.7 no.4
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• pp.22-26
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• 1998

The purpose of this experimenL is to investigate the magnetic anisotropy and microwave absorbing properties in M-type Bat territe (${BaFe}_{12-2X}{A}_{X}{Me}_{X}{O}_{19}$), where $Fe_{3+}$ is substituted by $Ti_{4+}$ in A site and $Co_{2+}$ in Me site. The saturation magnetization (Ms) is linearly decreased with the substitution rate(x) and the coerciviLy (He) is rapidly decreased in accordance with the reduction in t the magnetocrystalline anisotropy For the specimen with x=0.8 and thickness of 2 mm, the reflection loss calculated from the n material constants is less than -10 dB (90% absorption) in the frequency range of 10~16 GHz. The absorption loss is pre이.ctcd t to be more than 20 dElern in the frequency range of 12-16 GHz. The results demonstrate that the Ti-Co substituted M-type Ba-ferrite can be effectively used as a microwave absorber at high frequency range.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.123-128
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• 2009

This study was conducted to evaluate the weight reduction effect of yeast hydrolysate-SR101. Thirty female college students participated in a 6 week weight control program. All subjects were randomly assigned to either the placebo group, YH-SR101 (yeast hydrolysate-SR101) group, or eX diet (product of yeast hydrolysate-SR101) group. The mean energy intake of the placebo group was 1445.2${\pm}$364.0 kcal (carbohydrate: 60.1%, protein: 25.6%, fat: 14.3%), while those of the YH-SR101 and the eX diet group were 1505.6${\pm}$296.2 kcal (carbohydrate: 60.5%, protein: 22.2%, fat: 14.8%) and 1353.8${\pm}$326.3 kcal (carbohydrate: 63.2%, protein: 20.9%, fat: 15.9%), respectively. The placebo group lost 0.19${\pm}$1.14 kg of body weight, while the treatment groups (YH-SR101 and eX diet) lost 1.13${\pm}$0.83 and 1.54${\pm}$0.74 kg of body weight, respectively. There were significant differences in the decrease in body weight between the placebo and the treatment group (p<0.05). There were also significant differences in the decrease in fat mass between the placebo and treatment group (p<0.05). Furthermore, the BMI of the YH-SR101 and the eX diet groups also differed significantly before and after the diet program (p<0.05). Additionally, the BMI and waist size reduction of the treatment groups (YH-SR101 and eX diet group) differed significantly when compared to the placebo (p<0.05). The reduction of the resting metabolic rate (RMR) blood glucose, total-cholesterol, HDL-cholesterol, LDL-cholesterol and triglyceride did not differ significantly among groups. Taken together, these findings indicate that consumption of yeast hydrolysate-SR101 and eX Diet may lead to decreased body weight and fat.

• The Journal of Fisheries Business Administration
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• v.22 no.2
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• pp.101-148
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• 1991

The fisheries cooperative (FC) performs the economic and nonprofitable activity to get the fundamental objective of enhancing cooperative members' economic and social position. The internal control system fitted for a local FC should be required for not only solving the resulting problem from the complexity of FC environment nowaday but also delegating authorities and performance from FC Federation to a local FC by implementing the local autonomy. The methodology of this study is to empirically test and to analyze the condition of FC internal control system (FCICS) by the questionnaire survey. The actual condition of FCICS in Korea is analyzed by the questionnaire and the detailed contents are as follows : (1) sending 208 questionnaire consisting of 162 questions, and receiving 92 replies from 39 manufactures (business firms) and 15 banks in Gyungnam and Pusan area and 25 FC and 13 agricultural cooperative (AC) in Korea, (2) the analyzed results of FC and AC are treated simultaneously. In the fundamentals of above analyzed results, the evaluation model of FCICS is tried to construct from the relationship between the financial condition of FC and the internal control elements through the stepwise regression method. (1) By the stepwise regression method, the number of FC officials $(X_1)$, the experimental number of regular auditing $(X_7)$, and auditing duty years $(X_8)$ are finally accepted as independent variables, (2) and the final model becomes $Y=-1.53526+0.34455X_1+0.24513X_7+0.16585X_8$/ and this model explains to the extent of 47.826%. From the above study, following proposals are to be suggested: (1) The function and problem of internal control in FCICS is able to be improved by enforcing the function of FCICS and enriching the management's recognition of FCICS (2) The cooperative president can bring up good FC by the rational operation of FCICS according to the size and the performance pattern of FC, adding up to enhance members' economic and social position.

• Journal of the Korean Chemical Society
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• v.47 no.4
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• pp.309-314
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• 2003

In order to find out the microscopic environmental information on the nonionic reverse micelle of Triton X-100/n-hexanol/water in cyclohexane, an absorption and fluorescence spectroscopic study has been conducted using a methylene blue(MB). The information on the microscopic states of water in the polar core of the reverse micelle has been found by investigating complex formation and solvatochromic behavior between MB and Triton X-100. As a result, it was found that there exist three states in the polar core of the reverse micelle. The measured values of $W(=[H_2O]/[Surf])$ for the three states of water are 0.71, 4.98, and 7.26, and the corresponding lifetimes of MB are $15.45 ns{\pm}0.56$, $12.27 ns{\pm}0.79$, and $8.28 ns{\pm}0.82$, respectively.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.8
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• pp.753-760
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• 2008

The present study is concerned with aerodynamic characteristics and reference trajectory generation of Hope-X in Approach/Landing phase. To create reference trajectory generation in A/L phase, detailed informations on lift and drag coefficients of Hope-X must be provided. To obtain these informations, aerodynamic characteristics of Hope-X are analyzed using the commercial CFD code, Fluent. The A/L phase is conceptually divided into three sub-phases: the Steepglide Slope phase for stability of vehicle, the Flare Maneuver phase for safety landing, the Circular Flare for smooth connecting with these both phases. The reference trajectory is obtained by determination of flight-path angle through geometrical formulas with consideration of aerodynamic coefficient and dynamic characteristic.

• Journal of Chest Surgery
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• v.28 no.8
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• pp.766-771
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• 1995

The trachea is defined as the airway from the inferior border of the cricoid cartilage to the top of the carinal spur. This paper would confirm the normal tracheal length of Korean adults through the actual measurement using the fiberoptic bronchoscopy. The subjects of this study were 25 patients, 13 males and 12 females between the age of 20 to 69 without abnormality on the neck, trachea, mediastinum and lung pharenchyme on the preoperative chest X-ray, who received the operations from the period of July to September, 1994. For those patients who had heart diseases, the cardiothoracic ratio was below 50%. The measurement was performed on the patients with endotracheal intubation under the general anesthesia in supine and neutral position. The tracheal length was calculated by the difference between the length from the tip of the endotracheal tube [E-tube to carina and to the needle which was inserted into the E-tube at the lower border of the palpated cricoid cartilage, by inserting the broncoscopy through the E-tube. The result was as follow : 1 The measured tracheal length for men was 11.8 0.2 cm[mean standard deviation and women was 10.5 0.3 cm, and that was longer than this [p<0.01 . The average was 11.2 1.0 cm and the standard error was 0.20 cm. 2 According to the correlation between the tracheal length to weight, height[Ht , age, and body surface area[BSA respectively, the Ht [p=0.003 , age [p=0.055 , and the BSA[p=0.017 were significant, while weight was not [p=0.314 . 3 From the regression analysis of the tracheal length[T.L. to the Ht, Age, and the BSA which were significant, the following equation was derived.i Ht : T.L.= -1.29 + 0.076 x Ht [P=0.003 ii Age: T.L.= 10.04 + 0.028 x Age [P=0.055 iii BSA : T.L.= 5.60 + 3.48 x BSA [P=0.017 iv In multi-regression : T.L. = -4.15 + 0.034 x Age + 0.085 x Ht [P=0.0002]