• Title/Summary/Keyword: high-Q

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Development of Quality Assessment Tool and Application to Customer-Oriented Hospital Foodservice Management (고객지향적 병원 급식서비스 운영을 위한 질 평가 도구 개발 및 적용)

  • 이해영;장승희;양일선
    • Journal of Nutrition and Health
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    • v.37 no.4
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    • pp.329-338
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    • 2004
  • The purposes of this study were to : a) develop the quality assessment tool of hospital foodservice management, b) evaluate the S hospital's foodservice quality by this tool, and c) do the feasibility study about this tool in hospital food-service field by establishing quality management strategies. The developed quality assessment tool of hospital food-service management was consisted of 20 items for quality evaluation by Likert 5 point scale and two additional questions with the most satisfactory item and the most unsatisfactory item. As a result of evaluation, S hospital's foodservice quality was somewhat high, on the factor 'personnel attitude', especially. The IPA technique proved nine items including Q5, Q7, Q8, Q11, Q12, Q13, Q15, Q16, Q17 were in 'Doing Great, Keep It Up' and seven items such as Q1, Q2, Q3, Q6, Q9, Q18, Q19 that got high expectation and low perception needed to be focused in quality management strategy.

Q-switching in Medical High Power Laser (의료용 고출력 레이저에서 Q-스윗칭)

  • Cho, Chang-Ho;Park, Jong-Dae;Kim, Woon-Il;Cho, Kil-Hwan;Yun, Hyun-Sik
    • The Journal of Natural Sciences
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    • v.18 no.1
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    • pp.9-16
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    • 2007
  • The electro-optic Q-switching device for medical high power laser depends on the relation between the population inversion and the Q-switching time. The polarization changes in applied voltage must be experimented to use each $LiNbO_3$ crystal for Q-switching in high power laser.

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A 24 GHz I/Q LO Generator for Heartbeat Measurement Radar System (심장박동 측정 레이더를 위한 24GHz I/Q LO 발생기)

  • Yang, Hee-Sung;Lee, Ockgoo;Nam, Ilku
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.11
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    • pp.66-70
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    • 2016
  • This paper presents an 24 GHz I/Q LO generator for a heartbeat measurement radar system. In order to improve the mismatch performance between I and Q LO signals against process variation, a 24 GHz I/Q LO generator employing a low-pass phase shifter and a high-pass phase shifter composed of inductors and capacitors is proposed. The proposed 24 GHz I/Q LO generator consists of an LO buffer, a low-pass phase shifter and a high-pass phase shifter. It was designed using a 65 nm CMOS technology and draws 8 mA from a 1 V supply voltage. The proposed 24 GHz I/Q LO generator shows a gain of 7.5 dB, a noise figure of 2.3 dB, 0.1 dB gain mismatch and $4.3^{\circ}$ phase mismatch between I and Q-path against process and temperature variations for the operating frequencies from 24.05 GHz to 24.25 GHz.

Implementation of High-Q Bondwire Inductors on Silicon RFIC (RFIC를 위한 실리콘 기판에서의 고품질 본드와이어 인덕터 구현)

  • 최근영;송병욱;김성진;이해영
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.12
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    • pp.559-565
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    • 2002
  • Today, because a quality factor of the inductor fabricated on silicon substrate for RFIC is under 12, the realization of inductor haying high-Q is essential. In this paper, two inductors having improved Q-factor are proposed and fabricated using a bondwire on silicon substrate. Also for the PGS is applied to the same inductors, four inductors are fabricated finally The bondwire Inductors have the relatively low conductor loss due to wide cross-section area and they can reduce the parastic capacitance very much because they are located in the air. Simulation and measurement results show that the proposed inductors have much more improved Q-factor, 15, than a conventional spiral inductor at 1.5 GHz. Because of the use of an automatic bonding machine, we can fabricate the high - Q inductors very easily, repeatedly.

Realization of High Q Inductor on Low Resistivity Silicon Wafer using a New and simple Trench Technique (새로운 트랜치 방법을 이용한 저저항 실리콘 기판에서의 High Q 인덕터의 구현)

  • 이홍수;이진효유현규김대용
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.629-632
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    • 1998
  • This paper presents a new and simple technique to realize high Q inductor on low resistivity silicon wafer with 6 $\Omega$.cm. This technique is very compatible with bipolar and CMOS standard silicon process. By forming the deep and narrow trenches on the low resistivity wafer substrate under inductor pattern, oxidizing and filling with undoped polysilicon, the low resistivity silicon wafer acts as high resistivity wafer being suitable for the fabrication of high Q inductor. By using this technique the quality factor (Q) for 8-turn spiral inductor was improved up to max. 10.3 at 2 ㎓ with 3.0 $\mu\textrm{m}$ of metal thickness. The experiment results show that Q on low resistivity silicon wafer with the trench technique have been improved more than 2 times compared to the conventional low resistivity silicon wafer without trenches.

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Stomatal Control and Strategy Segregation to Drought Stress in Young Trees of Several Oak Species (수종 참나무속 유식물의 건조스트레스에 대한 기공저항의 조절과 전략의 분화)

  • 김종욱;김준호
    • The Korean Journal of Ecology
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    • v.17 no.3
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    • pp.241-249
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    • 1994
  • Leaf diffusive resistance (LDR), stomatal density, length of guard cell and hair density of leaves of 6 oak species were determined under withdrawal of water, and their strategies of drought stress were analyzed by principal component analysis. LDR of Quercus acutissima, Q. aliena and Q. serrata increased earlier than those of the other species at high leaf water potential $({\Psi}_{leaf})$ or low water saturation deficit (WSD), which was an avoidance mechanism reducing damage by water stress. Q. variabilis with low stomatal density, small stomatal size and high hair density had avoidance mechanisms increasing LDR at high $({\Psi}_{leaf})$ However, Q. mongolica and Q. dentata increased LDR at low $({\Psi}_{leaf})$ as xeric species do. Results from principal component analysis on the 15 variables related to strategies of drought stress indicated that the 6 oak species were divided into 2 groups: (1) Q. acutissima, Q. aliena and Q. serrata as mesic habitat species and (2) Q. variabilis, Q. mongolica and Q. dentata as xeric habitat species. Among three xeric species Q. acutissima differed from the other two species in the drought strategies such as high hair density, low stornatal density, high leaf area ratio, stomatal closing at low $({\Psi}_{leaf})$ and small cell wall elasticity. The results could reasonably explain their drought strategies in natural habitat.

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The Simulation using LTCC Technology for High Q inductor realization (LTCC 공정을 이용한 High Q 인덕터 구현을 위한 Simulation)

  • Park, Je-Yung;Cha, Doo-Yeol;Yeo, Dong-Hun;Kim, Jong-Hei;Chang, Sung-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.06a
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    • pp.317-318
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    • 2006
  • 일반적인 CMOS공정으로는 높은 주파수 대역에서 높은 Q factor를 갖는 인덕터를 구현하는데 어렵고 이에 반해 RF ICs는 갈수록 high Q 를 가지는 인덕터가 요구되고 있다. 이를 LTCC 기판 위에 인덕터를 구현했을 때 높은 주파수 대역에서 성능을 알아보기 위해 모의 실험하였다. 인덕터를 설계하는데 있어서 인덕터 코일의 폭, 코일의 두께와 간격이 인덕터의 성능을 결정짓는다는 것을 고려하였고, MEMS 공정을 이용하여 high Q를 갖는 인덕터를 설계하였다. 인덕터의 전체 크기는 $330{\mu}m\;{\times}\;330{\mu}m$에서 선폭은 $30{\mu}m$, 선간의 간격은 $20{\mu}m$로 기판위에 $80{\mu}m$ 높이로 인덕터를 띄어서 설계하였고, 그리고 이를 LTCC 기판위에 high Q 의 인덕터 구현을 위해 simulation 한 결과가 Q값이 50 정도의 크기를 나타냈다.

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Vegetation Structures and Ecological Niche of Quercus serrata Forests (졸참나무림의 식생구조와 생태적지)

  • Lee, Mi-Jeong;Yee, Sun;Kim, Hyo-Jeong;Ji, Yun-Ui;Song, Ho-Kyung
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.1
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    • pp.50-58
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    • 2004
  • The aim of this study was to characterize the forest vegetation structure and site of Quercus serrata forest for ecological forest management and ecological niche. The results are as follows : The chemical properties of Q. serrata forest soil were 0.24% of total nitrogen, 8.27 of organic matter, 74ppm of available phosphorous, 1.64(me/100g) of Ca, 0.22(me/100g) of Mg, 0.74(me/100g) of K and 9.3(me/100g) of cation exchangeable capacity. The dominant species in Quercus serrata forest were Quercus serrata, Quercus acutissima, Quercus variabilis, Quercus mongolica, Styrax obassia, Fraxinus rhynchophylla and Styrax japonica. DBH analysis showed that Quercus serrata seems to remain as a dominant species for the present because they had random distribution based on few of big individuality, many of small and middle individuality. But the Q. serrata community is competing with Q. mongolica and F. rhynchophylla, whose density of small individuality has increased. With the classification of TWINSPAN, Q. serrata forest was classified three groups, such as Q. serrata-Acer mono, Q. serrata, Q. serrata-Q. acutissima communities. The results of the correlation analysis of Q. serrata major communities and environment factors are as follows; Q. serrata-A. mono community was found relatively in high elevated and eastern and northern area that has relatively high percentage organic matter. Also Q. serrata community was found in high elevated and eastern and northern area that has high percentage organic matter. Q. serrata-Q. acutissima community was found in low elevated and southern and western area that has low percentage organic matter.

Preparation and Its Stability of a Coenzyme Q10 Nanoemulsion by High Pressure Homogenization with Different Valve Type Conditions (초고압균질기 밸브 타입에 따른 coenzyme Q10 나노에멀젼의 제조 및 안정성)

  • Lim, Ji-Sun;Gang, Ho-Jin;Yoon, Sung-Woo;Kim, Hyeong-Min;Suk, Jong-Woo;Kim, Do-Un;Lim, Jae-Kag
    • Korean Journal of Food Science and Technology
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    • v.42 no.5
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    • pp.565-570
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    • 2010
  • A coenzyme Q10 nanoemulsion was prepared using high pressure homogenization with different valve type conditions (A, B, and C) and cycle numbers (1, 2, and 3). The particle size, transmittance, zeta potential, and coenzyme Q10 content of the prepared coenzyme Q10 nanoemulsion were measured. The stability of the prepared coenzyme Q10 nanoemulsion was evaluated on heating ($95^{\circ}C$), freezing ($-20^{\circ}C$), and different pH (2-10) conditions. Also, the prepared coenzyme Q10 nanoemulsion was stored at different temperatures of 4, 25, and $40^{\circ}C$ for 12 weeks to evaluate its storage stability. In this study, the optimal conditions of high pressure homogenization for the preparation of a coenzyme Q10 nanoemulsion were identified to be 150 MPa, C valve, and a cycle number of 3. The results showed that the prepared coenzyme Q10 nanoemulsion had an average particle size of 40 nm, generated no deposits or floating matter when stored at either 4 or $25^{\circ}C$ for 12 weeks, and displayed excellent dispersibility and transparency when processed at different pHs (4-10) or heating ($95^{\circ}C$) and, freezing ($-20^{\circ}C$) conditions. Our results indicated that a coenzyme Q10 nanoemulsion prepared by high pressure homogenization can be used for preparing beverages in the food industry.

The Forest Vegetation of Mt. Kaya National Park, Korea (가야산 국립공원의 삼림식생)

  • 정민호;유현경;길봉섭;신성은;김창환
    • The Korean Journal of Ecology
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    • v.20 no.2
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    • pp.145-151
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    • 1997
  • A census of the forest vegetation of Mt. Kaya National Park was taken with respect to the medthods of ordination and classification. Eight groups were classified by cluster analysis : Quercus mongolica, Q. mongolica-Sasa borealis, Q. serrata, Q. variabilis, Carpinus laxiflora, Cornus controversa, Fraxinus mandshurica and Pinus densiflora. Among them, the Q. mongolica group and Q. mongolica-S. borealis group, the F. mandshurica group and C. controversa group showed similar floristic compositions to each other. The interrelationship between the floristic compositon of the vegetation and soil environment was analyzed by PCA, the Q. mongolica group and the Q. mongolica-S. borealis group were distributed in areas of high CEC and total nitrogen content, while the Q. serrata. Q. variabilis. C. laxiflora and Pinus densiflora groups formed their communities in the more moderate areas of pH, soil moisture and soil organic matter. F. mandshurica and C. controversa groups were distributed in the areas of high soil moisture, soil organic matter, pH and available phosphate.

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