• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1518-1520
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• 2002

Purpose of this research compares best transfer speed about applied frequency and voltage using characteristic of $L_1-B_4$ mode and $L_1-B_8$ mode linear ultrasonic motor that use piezoelectric effect. By method of study, analyzed best transfer speed measuring and comparison load status that use actuality telephone card in $L_1-B_4$ mode linear ultrasonic motor and no-load status of $L_1-B_8$ mode linear ultrasonic motor. Experiment result is applied frequency(58.4Hz) in $L_1-B_4$ mode linear ultrasonic motor (load state) and the best transfer speed by 19.8[cm/s] at applied voltage(56V) point. Also, $L_1-B_8$ mode linear ultrasonic motor (no-load state) is best transfer speed by applied frequency(27.9kHz) and 32.96[cm/s] at applied voltage (50V) point.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.414-417
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• 2001

Recently, developments of device using characteristics of ceramics as a new technical material is in progress. While doing so, Ultrasonic motor which is a part of research & flat-type $L_1-B_8$ mode Ultrasonic motor and measured the operation characteristics of its. The size of USM is 80*20*1.5[$mm{^1}$](length*width*thickness) and is constructed with stator by piezo-ceramics and stainless elastic body and rotator by bearings. As results of experiments, the fastest speed of revolution($\upsilon$), the maximum torque(T) and the efficiency($\eta$) were 37.5[cm/sec], 5.0[mN$\cdot$M] and 1.17[%] respectively when 27.9[kHz], 150[gf], 50[V] were applied. SO, we think this flat-type $L{_1}-B{_8}$ mode Ultrasonic motor is able to be used for applications in forwarding device of a paper or electric card so on. Key Words: Flat=type $L{_1}-B{_8}$ mode Ultrasonic Motors, Piezoelectric ceramics, forwarding device.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.245-251
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• 2006

This study was performed to investigate the changes of vitamin A, vitamin E, vitamin $B_l$ and vitamin $B_2$ contents in cow's raw milk collected from dairy farms in Chungcheong-do and Jeolla-do for a year. The contents of fat soluble vitamin A and E were changed as seasonal effect, but water soluble vitamin $B_l$ and $B_2$ contents were not changed as seasonal effect. Vitamin A content in cow's raw milk was as follows [minimum ${\sim}$maximum (mean), ug/100 mL]; $35.1{\sim}59.0$ (44.4) in spring, $36.7{\sim}65.6$ (50.0) in summer, $28.7{\sim}61.2$ (46.8) in autumn and $29.9{\sim}57.8$ (43.1) in winter. In case of vitamin E was as follows [minimum${\sim}$maximum (mean), ug/100 mL]; $28.3{\sim}59.2$ (45.8) in spring, $39.6{\sim}69.9$ (58.8) in summer, $35.0{\sim}62.8$ (46.2) in autumn and $26.0{\sim}55.4$ (41.5) in winter. In case of vitamin $B_l$ was as follow [minimum${\sim}$maximum (mean), ug/100 mL]; $27.7{\sim}57.9$ (42.84) in spring, $32.4{\sim}66.1$ (49.39) in summer, $34.1{\sim}63.7$ (46.69) in autumn and $20.6{\sim}61.4$ (43.20 in winter. The amounts of vitamin $B_2$ in cow's raw milk was as follows [minimum${\sim}$maximum (mean), ug/100 mL]; $150{\sim}182$ (160 in spring, $145{\sim}185$ (163) in summer, $149{\sim}180$ (166) in autumn and $148{\sim}190$ (167) in winter.

• Food Science and Preservation
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• v.14 no.6
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• pp.702-708
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• 2007

The effects of pectinase treatment and other processing conditions on juice yield from Rubus coreanus, and physicochemical changes during alcohol fermentation, were investigated. The yield from R. coreanus increased by 8.60% with Pectinex 100L treatment (500 ppm, 30 min) compared to a control group. The soluble solid content in the group fermented at $24^{\circ}Brix$ by addition of sucrose (24B-group), and the group fermented at $8^{\circ}Brix$ by addition of 16% sucrose after 4 days of fermentation (8B-group) decreased to $8.2{\sim}8.3$ and $7.7{\sim}8.0%$ after 10 days of fermentation, respectively, and no significant differences were observed with Pectinex 100L treatment. Initial titratable acidity in the enzyme treatment was slightly higher ($1.18{\sim}1.22%$) than for the control group (1.02%). The initial $L^*$ and $b^*$ values of R. coreanus juice decreased with enzyme treatment, and the $a^*$ value increased, but the color difference (${\Delta}E$) between the control and enzyme treatment gradually decreased with fermentation time. The ethanol contents in the 24B-group and the 8B-group were $16.01{\sim}16.22%$ and $13.29{\sim}13.52%$, respectively, after 10 days of fermentation. The methanol contents in the enzyme treatment and the control were $0.359{\sim}0.404$ and $0.520{\sim}0.604$ mg/mL, respectively, and within standard regulations (1 mg/mL).

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.421-422
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• 2008

In this paper, CMOS RF front-end circuits for an L1/L5 dual-band global positioning system (GPS)/Galileo receiver are designed in $0.13\;{\mu}m$ CMOS technology. The RF front-end circuits are composed of an RF single-to-differential low noise amplifier, an RF polyphase filter, two down-conversion mixers, two transimpedance amplifiers, a IF polyphase filter, four de-coupling capacitors. The CMOS RF front-end circuits provide gains of 43 dB and 44 dB, noise figures of 4 dB and 3 dB and consume 3.6 mW and 4.8 mW from 1.2 V supply voltage for L1 and L5, respectively.

• Journal of Ginseng Research
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• v.38 no.1
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• pp.73-77
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• 2014

Field and nutrient cultures of American ginseng (Panax quinquefolius L.) were used to establish foliar symptoms related to boron (B) concentration in leaves and soils, and to evaluate radish as a time-saving model system for B nutrition. Application of excess B, 8 kg/ha versus the recommended 1.5 kg/ha, to field plantings of 2-, 3-, and 4-yr-old American ginseng plants just prior to crop emergence caused, within 4 wk after crop emergence, leaf symptoms of chlorosis followed by necrosis starting at the tips and progressing along the margins. The B concentration in leaves of 2-4-yr-old plants receiving 1.5 kg/ha Bwas $30{\mu}g/g$ dry mass compared to $460{\mu}g/g$ dry mass where 8 kg/ha B was applied. Similarly, B concentration in soils receiving the lower B concentration was 1.8 mg/g dry mass and $2.2-2.8{\mu}g/g$ dry mass where the higher B concentration was applied. Application of 8 kg/ha B reduced the dry yield of 3rd-yr roots by 20% from 2745 kg/ha to 2196 kg/ha and 4th-yr roots by 26% from 4130 kg/ha to 3071 kg/ha. Ginseng seedlings and radish were grown under greenhouse conditions in nutrient culture with four B concentrations ranging from 0 mg/L to 10 mg/L. At 5 mg/L and 10 mg/L ginseng and radish developed typical leaf B toxicity symptoms similar to those described above for field-grown plants. Increasing B in the nutrient solution from 0.5 mg/L to 10 mg/L decreased, in a linear fashion, the root and leaf dry mass of ginseng, but not radish. Given the many similarities of ginseng and radish to B utilization, radish might be used as a timesaving model system for the study of B, and other micronutrients, in the slow-growing perennial ginseng.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.7
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• pp.292-297
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• 2002

In this paper, a flat-type $L_{-}$-$B_{8}$ mode Ultrasonic Motor[USM] having the size of 80 x 20 x ${1.5}mm^3$($l{\times}\omega{\times}t$) was designed and fabricated to examine the characteristics of an ultrasonic vibration. We used ANSYS simulation program based on FEM to get the optimum design of this USM. As results of experiment, the fastest speed of revolution(v), the maximum torque(T) and the efficiency(n) were 37.5cm/s, 5.0 mN.m and 1.17% when 27.9KHz, 150N, 50V were applied respectively. And this flat-type $L_{-}$-$B_{8}$ mode USM could be controlled the speed of rotor revolution by applied voltage, frequency and pre-load of rotor as well as showed the characteristics of typical drooping torque-speed, large torque and high speed. So, we think that this flat-type $L_{-}$-$B_{8}$ mode USM has characteristics of enough torque and velocity to be usable for applications in forwarding device of an electric card or a paper, etc.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.1
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• pp.19-24
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• 2010

Bumblebees are widely used to pollinate crops in greenhouses and fields. Here, we investigated whether different wake-up treatments during a short period of 1~3 days just before indoor rearing has any effects on oviposition and colony development of $CO_2$-treated Bombus ignitus queens and artificially hibernated B. terrestris queens The wake-up regimes were defined as 16L for 1 day (16L-1), 16 L per day for 3 days (16L-3), 24L for 1 day (24L-1), or 24D for 1 day (24D-1). Among these wake-up treatments, the oviposition rate and preoviposition period of B. ignitus queens reared at 24L-1 were 16.7~25.1% higher and 1.0~3.5 days shorter than other wake-up treatments. B. terrestris queens reared at 24L-1 also showed the best results for egg-laying characteristics, which were 8.9~18.8% higher for oviposition and 0.6~3.5 days shorter for preovipostion period than other wake-up treatments. Furthermore, B. terrestris queens reared at 24L-1 were 17.5% and 13.8% higher in rate of colony foundation and queen production, respectively, than other wake-up treatments. These results show that the most favorable wake-up treatment just before rearing for egg-laying and colony developmental characteristics of B. ignitus and B. terrestris queens was 24L-1. Overall, our findings indicate that a wake-up treatment just before rearing was effective for colony initiation and colony development of bumblebee queens.

• Journal of Environmental Science International
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• v.19 no.2
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• pp.209-215
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• 2010

This study is an endeavor to evaluate the risk assessment of hazardous(aflatoxin $B_1$) in medicines from oriental medical prescription which are circulated much recently. For that, twelve globular and granule types, seven liquid types of herbal medicine were bought to compare and analyze the content of aflatoxin aflatoxin B_1), which are harmful to human body. Woo Hwang Cheong Sim Hwan of Aflatoxin $B_1$ concentration lower than the standard accepted by all the products have been detected, B company(tradition) is the concentration of $1.24\;{\mu}g/kg$, C company $1.04\;{\mu}g/kg$, A company(tradition) and B company did not detect. And the general pill of aflatoxin B1 concentration lower than the standard accepted by all the products have been detected, S-1 is the concentration of $1.8\;{\mu}g/kg$, S-2 of $1.04\;{\mu}g/kg$, S-3 of $0.88\;{\mu}g/kg$, S-4 of $9.32\l\;{\mu}g/kg$, S-6 of $7.8\;{\mu}g/kg$, S-5 did not detect. All the products eundan allowed in the concentration of aflatoxin $B_1$ levels were lower than detection, D company of $0.96\;{\mu}g/kg$, E company concentration was not detected. The liquid product of aflatoxin $B_1$ concentration was found liwer than the standard accepted by all the product, L-3 concentration of $0.8\;{\mu}g/kg$, K-4 was detected in the $1.16\;{\mu}g/kg$, L-1 and L-2 is not detected, L-5 concentration of $15\;{\mu}g/kg$, L-7 is detected as $1.08\;{\mu}g/kg$ and, L-6 was not detected.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.875-882
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• 2021

To minimize occupational noise induced hearing loss, it is recommended that workers should not be exposed to noise levels exceeding 85 dBA for over 8 h. In the present study, noise exposure levels were measured for seven workers based on their tasks on a training ship. The A-weighted noise exposure level (L_ex,24h) was measured by taking into account the A-weighted equivalent continuous sound level (L_Aeq,i), duration (h) and noise contribution (L_ex,24h,i) from the workers' locations. Results are thus obtained for different job categories as follows: officer group L_ex,24h=56.1 dB, navigation crew L_ex,24h=58.9 dB, navigation cadet L_ex,24h=62.0 dB, ship's cook L_ex,24h=64.3 dB, engine cadet L_ex,24h=91.1 dB, engineer L_ex,24h=91.1 dB, and engine crew L_ex,24h=95.1 dB. It was determined that the engineers, engine crews, and engine cadets in charge of machinery must wear hearing protection devices. By wearing hearing protection devices when working in highly noisy engine rooms, it is estimated that the noise expose levels could be reduced by the following amounts: engineer L_ex,24h=23.1 dB, engine Crew L_ex,24h=24.4 dB, and engine cadet L_ex,24h=21.5 dB. Moreover, if the no. 2 lecture room and mess room bottom plates in the cadets accommodations were improved to the 64 mm A-60-class floating plates, then further reductions are possible as follows: navigation cadet L_ex,24h=4.3 dB and engine cadet L_ex,24h=1.8 dB.