• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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• v.7 no.1
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• pp.27-31
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• 1996

The voice of aged persons is known generally to be somewhat different from that of other adults, suggesting that laryngeal change occurs with advancing age. However, because knowledge of the voice characteristics of aged persons is limited, it is difficult to judge whether their voices arc normal. Chart review and laryngoscopic examination from ninety-one patients with hoarseness over the age of 60(1st group) and one hundred sixteen patients with hoarseness below the age of 50(2nd group) were done to define aging related voice disorders. The following results were obtained. 1) Associated diseases related to laryngeal disease were hypertension(12%), pulmonary disease(4.4%), thyroid disease(1.1%) in 1st group and hypertension(9.5%), thyroid disease(1.7%) in 2nd group. 2) The underlying diseases causing hoarseness in order of frequency were benign vocal fold lesion(37.7%), inflammatory disease(36.8%), functional dysphonia(17%) in 1st group and benign vocal fold lesion(43.6%), functional dysphonia(26.3%), inflammatory disease(16.5%) in 2nd group. 3) In stroboscopic findings, atrophy and sulcus of vocal cords are more prevalent in males than in females and edema of vocal cords is more common in females. Generally the voice characteristics of aged persons depend on the mass of the vocal folds which may be decreased through atrophy or be increased by edema. However, other factors such as systemic diseases, drug side effects and compensatory mechanism to presbylaryngis must be taken into account in diagnosing and treating voice disorders in aged persons.

• Journal of the Korean Magnetics Society
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• v.11 no.1
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• pp.8-13
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• 2001

Effects of casting Processes and lubricant addition were studied to improve remanence of 31RE-68TM-lB based sintered magnet by using axial pressing process. Strip casting was effective to get the fine and homogeneous microstructure without ${\alpha}$-Fe segregation. The strip cast flake resulted in narrower particle size distribution after jet milling with respect to the conventional cast ingot. During pressing step with a magnetic field, the particle alignment was increased by appropriate addition of liquid lubricant. In this study, it was revealed that narrow particle size distribution and appropriate addition of liquid lubricant were essential to improve the grain alignment and thus the remanence of Nd-Fe-B sintered magnet.

• Food Science and Preservation
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• v.14 no.6
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• pp.669-675
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• 2007

Quality characteristics of Kwamaegi (semi-dried saury) prepared by treatment of chitosan-ascorbate (CA) and vacuum drying at $40{\sim}60^{\circ}C$(VDK), and the effect of the Kwamaegi on serum lipid profiles and anti-oxidation-related enzyme activity in rats fed high fat diets were investigated. The preparation periods were $4.5{\sim}8.3$ hr in VDK, while naturally dried Kwamaegi (NDK) took 360480 hr. Total microbe contents of VDK and NDK were $0.2{\sim}0.5$ and 8.2 log CFU/g, respectively. There was no significant difference in amino-nitrogen content. Compared with NDK, the acid and peroxide value, and fishy flavor of VDK40 (dried at $40^{\circ}C$) were significantly lower, and the texture, color and overall acceptability were higher. In animal experiments, weight gain, content of LDL-cholesterol and lipid peroxide, activities of total (T) and O type (O) xanthine oxidase, and the O/T ratio (%) were significantly lower in the VDK40 diet group than in the NDK diet group. The content of HDL-cholesterol in the VDK40 diet group was higher than in the NDK diet group. These results suggest that preparing CA-treated Kwamaegi with vacuum-drying at $40^{\circ}C$ can be applied throughout the year, and may shorten preparation time and improve its microbiological safety and nutritional values.

• Electrical & Electronic Materials
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• v.8 no.6
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• pp.811-815
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• 1995

회토류계 영구자석은 종래의 Ferrite계나 Alnico계와 비교해서 대단히 강하여, 전기전자부품의 소형화에 크게 기여하고 있다. 최근에는, 전자기기산업 이외의 분야에 있어서도 그의 응용이 확대되어가고 있는 추세로 자성재료의 생산액은 매년 증가하고 있다. 회토류계 영구자석재료의 연구는 1960년대에 시작되어 Sm $Co_{5}$, Sm$_{2}$ $Co_{17}$ 화합물의 등장을 거쳐 현재는 1982년데 Sagawa 및 Croat가 독자적으로 발견한 Nd$_{2}$ Fe$_{14}$B 자석이 주류로 되고 있다. 그렇지만 이 화합물에는 다른 영구자석에 비하여 큐리온도가 낮은 결점이 있어서, 아직도 새로운 화합물의 탐색이 계속되고 있다. 그 중에서도, 1990년대에 Coey에 의해서 최초로 학회지에 보고되어진 Sm$_{2}$Fe$_{17}$N$_{x}$는, Nd$_{2}$Fe$_{14}$B와 같은 정도의 이론 최대에너지급, Sm $Co_{5}$에 대등한 거대한 이방성자장, 750K에 달하는 큐리온도등의 우수한 성질을 갖고 있어 Nd$_{2}$Fe$_{14}$B를 극복하는 자성재료로서 큰 기대가 되어진다. 되어진다.진다.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.135-141
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• 1990

Optical nonlinearity of laser heated Si with thickness of 160$\mu$m is investigated by pump-probe method. Si is heated by pdsed Nd:YAG laser of $TEM_{00}$-mode with pulse duration of 180$\mu$sec. Temperature change is monitored by observing transmittance change of probe light whose wavelength lies near band gap of Si. It is found that temperature rise is linearly proportional to incident laser intensity and the maximum temperat~re increment is measured to be $16^{\circ}C$ for the maximum incident intensity of 25KW/$\textrm{cm}^2$. From these results, the third order nonlinear susceptibility .d3) at the wavelength of 1.06$\mu$mis estimated to be $6.6\times10^{-5}$esu due to laser heating.

• The Korean Journal of Food And Nutrition
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• v.12 no.1
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• pp.55-62
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• 1999

Changes in the alliinase activity during the aging of pickled garlic samples prepared by the several methods were investigated. The activity of alliinase in raw garlic was 8,37 units/mg protein. The ac-tivity in the garlic pickled with swoy sauce was reduced to 4.57 units/mg with 52% remaining by 1st week of pickling and to 1.05 units/mg protein with 12% remaining by 2nd week of pickling. The ac-tivity of alliinase in the garlic pickled with vinegar was 2.79 units/mg protein with 32% remaining by 1st week of pickling and was 0.26 units/mg protein only with 3% remaining by 2nd week of pickling. The activity of alliinase in the garlic pickled with 10% salt solution was 5.06 units/mg protein with 58% remaining by 1st week of pickling. After one week pickling the juice of pickled garlic was removed. Then garlics were pickled again with vinegar. The allinase acting in was reduced to 0.85 units/mg pro-tein with 10% remaining by 2nd week of pickling. The activity of alliinase in the garlic pickled with vin-egar was 2.79 units/mg protein with 32% remaining by 1st week of pickling. The juice of pickled garlic was removed after one week. Then the galics were again pickled with saysauce. The allinase activity in the garlic the garlic pickled again with soy sauce was reduced to 0.43 units/mg protein with 5% remain-ing by 2 week of pickling.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.616-622
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• 1994

The oxidation of carbon monoxide by gaseous oxygen in the presence of a powdered $Nd_{1-x}Sr_xCoO_{3-y}$ solid solution as a catalyst has been investigated in the temperature range from 150$^{\circ}$C to 300$^{\circ}$C under various CO and $O_2$ partial pressures. The site of Sr substitution, nonstoichiometry, structure, and microstructure were studied by means of powder X-ray diffraction and infrared spectroscopy. The electrical conductivity of the solid solution has been measured at 300$^{\circ}$C under various CO and $O_2$ partial pressures. The oxidation rates have been correlated with 1.5-and 1.2-order kinetics with and without a $CO_2$ trap, respectively; first-and 0.7 order with respect to CO and 0.5-order to $O_2$. For the above reaction temperature range, the activation energy is in the range from 0.25 to 0.35 eV/mol. From the infrared spectroscopic, conductivity and kinetic data, CO appears essentially to be adsorbed on the lattice oxygens of the catalyst, while $O_2$ adsorbs as ions on the oxygen vacancies formed by Sr substitution. The oxygen vacancy mechanism of the CO oxidation and the main defect of $Nd_{1-x}Sr_xCoO_{3-y}$ solid solution are supported and suggested from the agreement between IR data, conductivities, and kinetic data.

• Journal of the Korea Institute of Military Science and Technology
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• v.24 no.5
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• pp.519-526
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• 2021

In this paper, an array antenna for LOS datalink for mounting UAV(Unmanned Aerial Vehicle) of low-probability of intercept is presented. For low RCS, radome was designed by conformal form, and other components were inserted into the UAV. The antenna of the transmitter and receiver are each composed of 12×12 array antennas, and include a beam steering function by controlling the phase of the unit element for the Uni-directional pattern and the Bi-directional pattern. As a result of the measurement of the manufactured antenna, it was confirmed that all the required specifications were met, and the installing possibility of the UAV platform on low-probability of intercept in the future was confirmed.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.5
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• pp.577-587
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• 1998

• TTA Journal
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• s.88
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• pp.177-184
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• 2003