• Title/Summary/Keyword: DC/DC

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Doppler Radar System for Long Range Detection of Respiration and Heart Rate (원거리에서 측정 가능한 호흡 및 심박 수 측정을 위한 도플러 레이더 시스템)

  • Lee, Jee-Hoon;Kim, Ki-Beom;Park, Seong-Ook
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.25 no.4
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    • pp.418-425
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    • 2014
  • This paper presents a Ku-Band Doppler Radar System to measure respiration and heart rate. It was measured by using simultaneous radar and ECG(Electrocardiogram). Arctangent demodulation without dc offset compensation can be applied to transmitted I/Q(In-phase & Quadrature-phase) signal in order to improve the RMSE(Root Mean Square Error) about 50 %. The power leaked to receiving antenna from the transmitting antenna is always generated because of continuously opening the transceiver of CW(Continuous Wave) Doppler radar. As the output power increase, leakage power has an effect on the SNR(Signal-to-Noise Ratio) of the system. Therefore, in this paper, leakage cancellation technique that adds the signal having the opposite phase of the leakage power to the leakage power was implemented in order to minimize the decline of receiver sensitivity. By applying the leakage cancellation techniques described above, it is possible to measure the heart rate and respiration of the human at a distance of up to 35 m. the heart rate of the measured data at a distance of 35 m accords with the heart rate extracted from the ECG data.

A Study of 'uplift yang-qi to raise sinking' efficacy in Radix Bupleuri (시호(柴胡)의 승약작용에 관한 연구)

  • Park, Pil-Sang;Kang, Ok-Hwa;Lee, Go-Hoon;Lee, Kye-Suk;Ko, Ho-Yeon;Kwon, Dong-Yeul
    • The Korea Journal of Herbology
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    • v.21 no.4
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    • pp.213-218
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    • 2006
  • Objectives : Radix Bupleuri is from the dried root of the herb of the Perennial herbaceous plant, Bulpleurum falcatum L. or Bulpleurum chinense DC. or Bulpleurum. scorzonerifolium Willd., family Umbelliferae. Medicinal Properties are bitter and pungent in flavor, slightly cold in nature and attributed to the liver and gallbladder meridians. Actions in modern Materia Medica are regulate the functional relation of internal organs to relieve fever, disperse the stagnated liver-qi and uplift yang-qi to raise sinking. The ‘uplift yang-qi to raise sinking’ efficacy, out of three efficacies (regulate the functional relation of internal organs to relieve fever, disperse the stagnated liver-qi and uplift yang-qi to raise sinking), has been disputed in the medical profession for a long period. Hereupon, this study ascertained the reason why it has been disputed. Methods : With respect to this medicinal herb, the efficacies of regulate the functional relation of internal organs to relieve fever, disperse the stagnated liver-qi and uplift yang-qi to raise sinking were described as to what was written in ‘Shen Nong's Herbal’ from Chin and Han dynasties until Jin and Yuan dynasties. Results : The beginning of Jin and Yuan dynasties, it began to deal with the ‘uplift yang-qi to raise sinking’ efficacy and so it has been carried on modern textbooks and medical books. The reason why it was added is that it was influenced by the theory of ‘Raise Sinking’ advocated by Zhang jieku who lived in the period of Jin and Yuan dynasties. Since then, the properties of ‘Radix Bupleuri’ have been wrongly known to the public. Additionally, ‘Radix Stellariae Seu Gypsophilae’, which was begun to be introduced from the Four Cities since the Five Dynasties, has been combined with the best stuffs of ‘Radix Bupleuri’ produced from Yin Zhou. Consequently, its original properties were remarkably disordered. Likewise, respective medical schools’ theories were changed by the influence of ‘Bulpleurum. scorzonerifolium Willd’ begun to be used since Tang dynasty. Conclusion : it is considered that the current ‘Raise Sinking’ efficacy of Radix Bupleuri is unreasonable to be applied to the efficacy of the whole Radix Bupleuri because it is limited to certain species.

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Phase transformation and magnetic properties of $Ni_xFe_{100-x}$ thin films deposited by a co-sputtering (동시 스퍼터링법으로 제조된 $Ni_xFe_{100-x}$ 박막의 상변화와 자기적 특성)

  • Kang, Dae-Sik;Song, Jong-Han;Nam, Joong-Hee;Cho, Jeong-Ho;Chun, Myoung-Pyo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.19 no.6
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    • pp.282-287
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    • 2009
  • $Ni_xFe_{100-x}$ films with a thickness of about 100nm were deposited on Si(100) substrates at room temperature by a DC magnetron co-sputtering using Fe and Ni targets. Compositional, structural, electrical and magnetic properties of the films were investigated. $Ni_{67}Fe_{33}$, $Ni_{55}Fe_{45}$, $Ni_{50}Fe_{50}$, $Ni_{45}Fe_{55}$, $Ni_{40}Fe_{60}$ films are obtained by increasing the sputtering power of the Fe target. The films of x < 55 have BCC structure and show the phase transformation after annealing at the range of $300{\sim}450^{\circ}C$ for 2 h. On the other hand, the films of x < 50 have the mixed crystalline phases of BCC and FCC after the annealing treatment. The saturation magnetization was decreased initially by the phase transformation effect but then increased again after annealing at $450^{\circ}C$ due to the grain growth and crystallization of BCC phases.

Re-reading Birmingham Cultural Studies for 'Non-representational Cultural Studies' in South Korea -with Stuart Hall's Philosophy and Methodology (버밍엄 문화연구에 대한 재고찰과 '비재현적 문화연구'의 필요성 -스튜어트 홀과 주요 연구자들의 사유와 방법론을 중심으로)

  • Park, Sungwoo
    • Korean journal of communication and information
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    • v.70
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    • pp.95-131
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    • 2015
  • This paper points out the importance and necessity of 'non-representational cultural studies' in South Korea. For this, Stuart Hall's seminal research "Encoding/Decoding" (1980) is to be re-read thoroughly with articulation of his later practices. Along with, this research looks at how non-representational cultural studies can expand the scope of understanding various comtemporary phenomenon of our society usually untold by mainstream cultural studies' themes and methods which focus more on abstract division and representational discourses. Notably, Stuart Hall's influential early writings and practical later engagements could bring us to think more seriously not only where contemporary cultural studies goes but also where cultural studies in South Korea should go. This article narrows the attention into Hall's EC/DC theory and related research-practical activity influenced by his own philosophy. Indeed, cultural studies in South Korea still seems to be almost same as early Birmingham cultural studies especially in the aspects like research direction and theme; however, that is quite unusual in some points. These points are to be explicated by this attempt of following Hall's meaningful life-long trajectory as a cultural activist as well as media theorist.

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Design and Implementation of 8b/10b Encoder/Decoder for Serial ATA (직렬 ATA용 8b/10b 인코더와 디코더 설계 및 구현)

  • Heo Jung-Hwa;Park Nho-Kyung;Park Sang-Bong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.1A
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    • pp.93-98
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    • 2004
  • Serial ATA interface Is inexpensive comparatively and performance is superior. So it is suitable technology in demand that now require data transmission and throughput of high speed. This paper describes a design and implementation of Serial ATA Link layer about error detection and 8b/10b encoder/decoder for DC balance in frequency 150MHz. The 8b/10b Encoder is partitioned into a 5b/6b plus a 3b/4b coder. The logical model of the block is described by using Verilog HDL at register transistor level and the verified HDL is synthesized using standard cell libraries. And it is fabricated with $0.35{\mu}m$ Standard CMOS Cell library and the chip size is about $1500{\mu}m\;*\;1500{\mu}m$. The function of this chip has been verified and tested using testboard with FPGA equipment and IDEC ATS2 test equipment. It is used to frequency of 100MHz in verification processes and supply voltage 3.3V. The result of testing is well on the system clock 100MHz. The designed and verified each blocks may be used IP in the field of high speed serial data communication.

A practial design of direct digital frequency synthesizer with multi-ROM configuration (병렬 구조의 직접 디지털 주파수 합성기의 설계)

  • 이종선;김대용;유영갑
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.12
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    • pp.3235-3245
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    • 1996
  • A DDFS(Direct Digital Frequency Synthesizer) used in spread spectrum communication systems must need fast switching speed, high resolution(the step size of the synthesizer), small size and low power. The chip has been designed with four parallel sine look-up table to achieve four times throughput of a single DDFS. To achieve a high processing speed DDFS chip, a 24-bit pipelined CMOS technique has been applied to the phase accumulator design. To reduce the size of the ROM, each sine ROM of the DDFS is stored 0-.pi./2 sine wave data by taking advantage of the fact that only one quadrant of the sine needs to be stored, since the sine the sine has symmetric property. And the 8 bit of phase accumulator's output are used as ROM addresses, and the 2 MSBs control the quadrants to synthesis the sine wave. To compensate the spectrum purity ty phase truncation, the DDFS use a noise shaper that structure like a phase accumlator. The system input clock is divided clock, 1/2*clock, and 1/4*clock. and the system use a low frequency(1/4*clock) except MUX block, so reduce the power consumption. A 107MHz DDFS(Direct Digital Frequency Synthesizer) implemented using 0.8.mu.m CMOS gate array technologies is presented. The synthesizer covers a bandwidth from DC to 26.5MHz in steps of 1.48Hz with a switching speed of 0.5.mu.s and a turing latency of 55 clock cycles. The DDFS synthesizes 10 bit sine waveforms with a spectral purity of -65dBc. Power consumption is 276.5mW at 40MHz and 5V.

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Temperature Dependence on Dry Etching of $ZrO_2$ Thin Films in $Cl_2/BCl_3$/Ar Inductively Coupled Plasma ($Cl_2/BCl_3$/Ar 유도 결합 플라즈마에서 온도에 따른 $ZrO_2$ 박막의 식각)

  • Yang, Xue;Kim, Dong-Pyo;Lee, Cheol-In;Um, Doo-Seung;Kim, Chang-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.145-145
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    • 2008
  • High-k materials have been paid much more attention for their characteristics with high permittivity to reduce the leakage current through the scaled gate oxide. Among the high-k materials, $ZrO_2$ is one of the most attractive ones combing such favorable properties as a high dielectric constant (k= 20 ~ 25), wide band gap (5 ~ 7 eV) as well as a close thermal expansion coefficient with Si that results in good thermal stability of the $ZrO_2$/Si structure. During the etching process, plasma etching has been widely used to define fine-line patterns, selectively remove materials over topography, planarize surfaces, and trip photoresist. About the high-k materials etching, the relation between the etch characteristics of high-k dielectric materials and plasma properties is required to be studied more to match standard processing procedure with low damaged removal process. Among several etching techniques, we chose the inductively coupled plasma (ICP) for high-density plasma, easy control of ion energy and flux, low ownership and simple structure. And the $BCl_3$ was included in the gas due to the effective extraction of oxygen in the form of $BCl_xO_y$ compounds. During the etching process, the wafer surface temperature is an important parameter, until now, there is less study on temperature parameter. In this study, the etch mechanism of $ZrO_2$ thin film was investigated in function of $Cl_2$ addition to $BCl_3$/Ar gas mixture ratio, RF power and DC-bias power based on substrate temperature increased from $10^{\circ}C$ to $80^{\circ}C$. The variations of relative volume densities for the particles were measured with optical emission spectroscopy (OES). The surface imagination was measured by scanning emission spectroscope (SEM). The chemical state of film was investigated using energy dispersive X-ray (EDX).

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Characteristic of ITO-Ag-ITO multilayer thin films grown by linear facing target sputtering system (선형대향타겟 스퍼터로 성장시킨 ITO-Ag-ITO 다층박막의 특성 연구)

  • Jeong, Jin-A;Choi, Kwang-Hyuk;Lee, Jae-Young;Lee, Jung-Hwan;Bae, Hyo-Dae;Tak, Yoon-Heung;Ye, Min-Su;Kim, Han-Ki
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.66-66
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    • 2008
  • 본 연구에서는 ITO/Ag/ITO 다층 박막을 유기발광소자와 플렉시블 광전소자의 전극으로 적용하기 위하여 선형 대항 타겟 스퍼터(Linear facing target sputter) 시스템을 이용하여 성막하였고, ITO/Ag/ITO 다층박막의 전기적, 광학적, 구조적 특성을 분석하였다. 선형 대항 타겟 스퍼터 시스템은 강한 일방항의 자계와 타겟에 걸린 음극에 의해 전자의 회전, 왕복 운동이 가능해 마주보는 두 ITO 타겟 사이에 고밀도의 플라즈마를 구속 시켜 플라즈마 데미지 없이 산화물 박막을 성막시킬 수 있는 장치이다. 대항 타겟 스퍼터 시스템을 이용하여 성막한 ITO 전극을 DC power, working pressure, Ar/O2 ratio 에 따른 특성을 각각 분석하였다. glass 기판위에 최적화된 ITO 전극을 bottom layer로 두고, bottom ITO layer 위에 thermal evaporation 을 이용하여 Ag 박막을 6~20nm의 조건에 따라 두께를 다르게 성막하고, Ag 박막을 성막한 후에 다시 bottom ITO 전극과 같은 조건으로 ITO 전극을 top layer로 성막 하였다. 두 비정질의 ITO 전극 사이에 매우 앓은 Ag 박막을 성막 함으로 해서 glass 기판위에 ITO/Ag/ITO 다층 박막전극은 매우 낮은 저항과 높은 투과도를 나타낸다. ITO/Ag/ITO 박막의 전기적 광학적 특성을 보기 위해 hall measurement와 UV/visible spectrometer 분석을 각각 진행하였다. ITO/Ag/ITO 다층 박막 전극이 매우 얇은 두께임에도 불구하고 $4\Omega$/sq.의 낮은 면저항과 85%의 높은 투과도를 나타내는 이유는 ITO/Ag/ITO 전극 사이에 있는 Ag층의 표면 플라즈몬 공명 (SPR) 현상으로 설명할 수 있다. ITO/Ag/ITO 전극의 Ag의 거동을 분석 하기위해 FESEM분석과 synchrotron x-ray scattering 분석을 하였다. ITO/Ag/ITO 전극의 Ag층이 islands의 모양에서 연속적으로 연결되는 변화과정 중에 SPR현상이 일어남을 알 수 있다. 여기서, 대항 타겟 스퍼터 시스템을 이용하여 성막한 ITO/Ag/ITO 다층박막을 OLED 또는 inverted OLEDs의 top 전극으로의 적용 가능성을 보이고 있다.

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The Trend of Acute Respiratory Tract Infections and Antibiotic Prescription Rates in Outpatient Settings using Health Insurance Data (건강보험청구자료를 이용한 외래 급성 호흡기계 질환 방문과 항생제 처방률 변화 분석)

  • Kim, Jee-Ae;Park, Juhee;Kim, Bo-Yun;Kim, Dong-Sook
    • Korean Journal of Clinical Pharmacy
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    • v.27 no.3
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    • pp.186-194
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    • 2017
  • Objectives: A significant concern has been raised about the emerging resistance that is largely caused by the excessive or inappropriate use of antibacterial agents for viral respiratory infections. This study investigated the trend of respiratory tract infections (RTIs) and the use of antibiotics. Methods: Utilizing the national level health insurance claims data from 2005 to 2008, we examined encounter days, antibiotic use, and the prescription rate for respiratory tract infections including upper respiratory tract infections (URTIs), lower respiratory tract infections (LRTIs), and otitis media in outpatient settings. The antibiotic use was measured as defined daily dose per 1,000 patients per day (DDD/1,000 patients/day). Results: The visit for URTI increased from 141,693,465 in 2005 to 120,717,966 in 2008 and the visit for LRTI decreased from 61,778,718 to 66,930,122. For RTIs, prescription rates of antibiotics decreased from 65.2% to 58.5% for URTIs and 76.9% to 68.3% for LRTIs from 2005 to 2008. The antibiotic use decreased to 20.85 DDD/1,000 patients/day after a significant increase of 22.01 DDD/1,000 patients/day in 2006. Among antibiotics, J01CR had the highest use- 7.93 DDD/1,000 patients/day followed by J01DC of 3.71 DDD/1,000 patients/day and J01FA of 3.2 DDD/1,000 patients/day. One notable trend is that J01FA presented a continuous increase in antibiotic use from 2.3 in 2005 to 3.26 DDD/1,000 patients/day in 2008. Conclusion: The use of antibiotics had poor compliance to guidelines for RTIs. Despite decrease in the use of antibiotics, prescription rates for URTIs were still about 50% indicating that the delayed prescribing antibiotics (or wait-and-see) were not observed.

Design of a Low-Power CMOS Fractional-N Frequency Synthesizer for 2.4GHz ISM Band Applications (2.4GHz ISM 대역 응용을 위한 저전력 CMOS Fractional-N 주파수합성기 설계)

  • Oh, Kun-Chang;Kim, Kyung-Hwan;Park, Jong-Tae;Yu, Chong-Gun
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.6
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    • pp.60-67
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    • 2008
  • A low-power 2.4GHz fractional-N frequency synthesizer has been designed for 2.4GHz ISM band applications such as Bluetooth, Zigbee, and WLAN. To achieve low-power characteristic, the design has been focused on the power optimization of power-hungry blocks such as VCO, prescaler, and ${\Sigma}-{\Delta}$ modulator. An NP-core type VCO is adopted to optimize both phase noise and power consumption. Dynamic D-F/Fs with no static DC current are employed in designing the low-power prescaler circuit. The ${\Sigma}-{\Delta}$ modulator is designed using a modulus mapping circuit for reducing hardware complexity and power consumption. The designed frequency synthesizer which was fabricated using a $0.18{\mu}m$ CMOS process consumes 7.9mA from a single 1.8V supply voltage. The experimental results show that a phase noise of -118dBc/Hz at 1MHz offset, the reference spur of -70dBc at 25MHz offset, and the channel switching time of $15{\mu}s$ over 25MHz transition have been achieved. The designed chip occupies an area of $1.16mm^2$ including pads where the core area is only $0.64mm^2$.