• Title/Summary/Keyword: BBA

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A 900 MHz ZigBee CMOS RF Transceiver Using Switchless Matching Network (무스위치 정합 네트워크를 이용한 900 MHz ZigBee CMOS RF 송수신기)

  • Jang, Won Il;Eo, Yun Seong;Park, Hyung Chul
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.8
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    • pp.610-618
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    • 2017
  • This paper presents a 868/915 MHz CMOS RF transceiver for the ZigBee application. Using a switchless matching network, the off chip switch is removed to achieve the low cost RF transceiver, and by the elimination of the switch's insertion loss we can achieve the benefits for the RF receiver's noise figure and transmitter's power efficiency at the given output power. The receiver is composed of low-noise amplifier, mixer, and baseband analog(BBA) circuit. The transmitter is composed of BBA, mixer, and driver amplifier. And, the integer N type frequency synthesizer is designed. The proposed ZigBee RF full transceiver is implemented on the $0.18{\mu}m$ CMOS technology. Measurement results show that the maximum gain and the noise figure of the receiver are 97.6 dB and 6.8 dB, respectively. The receiver consumes 32 mA in the receiver mode and the transmitter 33 mA in the transmission mode.

Cerebral Aneurysms Arising from Unbranched Site of Intracranial Arteries (혈관가지가 없는 두개강내 혈관에서 발생한 뇌 동맥류)

  • Kim, Young Jin;Kim, Jae Min;Yi, Hyeong Joong;Bak, Koang Hum;Kim, Choong Hyun;Oh, Suck Jun
    • Journal of Korean Neurosurgical Society
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    • v.29 no.4
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    • pp.521-527
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    • 2000
  • Objective : In general, most of saccular aneurysms arise at arterial divisions, but those arising at unbranched site are rare. These aneurysms might impose neurosurgeons a formidable surgical challenge, due to uncommon features and a difficult surgical technique. Methods : Between the period of Jan. 1996 and Dec. 1998, a total of 110 cases of aneurysms were operated. Among them, five cases of unbranched site aneurysms were retrospectively analyzed through medical records, angiographic and operative findings. Results : The incidence of aneurysms unrelated to arterial branches was 4.5%. All cases presented with subarachnoid hemorrhage(SAH) ; three(60%) were at internal carotid artery(ICA) and two(40%) at middle cerebral artery (MCA). Two had a history of hypertension and three showed atherosclerotic changes in the arterial wall. One ICA and one MCA aneurysms proved to be a blood blister-like aneurysm(BBA) in their shape. Strikingly, a rapid neurological deterioration was shown in two ruptured ICA variants, which resulted in death and another two aneurysms left with morbidity. Conclusion : The preoperative neurological status in most cases was relatively poor compared to that of aneurysms arising at a branched site. Regarding its pathogenesis, atherosclerosis as well as hemodynamic factors may play an important role in formation of these variant aneurysms among various etiological factors. The overall prognosis of unbranched site aneurysms was worse than that of branched site aneurysms. In cases of BBAs, special attention was requisite to handle them during clipping and/or wrapping due to an easy fragile, thin aneurysmal wall.

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Optimization of Low Power CMOS Baseband Analog Filter-Amplifier Chain for Direct Conversion Receiver

  • Lee, Min-Kyung;Kwon, Ick-Jin;Lee, Kwy-Ro
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.4 no.3
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    • pp.168-173
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    • 2004
  • A low power CMOS receiver baseband analog circuit based on alternating filter and gain stage is reported. For the given specifications of the baseband analog block, optimum allocation of the gain, IIP3 and NF of the each block was performed to minimize current consumption. The fully integrated receiver BBA chain is fabricated in $0.18\;{\mu}m$ CMOS technology and IIP3 of 30 dBm with a gain of 55 dB and noise figure of 31 dB are obtained at 4.86 mW power consumption.

Effect of Offset of Bearing on Radiation Sound and Vibration in the Gear System (기어장치에서 베어링의 설치위치가 소음특성에 미치는 영향)

  • 류성기;이중희
    • Journal of the Korean Society of Safety
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    • v.13 no.1
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    • pp.34-39
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    • 1998
  • This paper describes a evaluation method of sound power radiated from the vibrating faces of a single stage gear box using sound radiation. The vibration caused from meshing gears is transmitted to the gear box faces through shafts and bearings. A Boundary Element Method (BEM) is developed to calculate the sound power radiated from the faces with their velocity response which is based on the Building Block Approach (BBA). Radiation efficiency as well as the sound intensity on the surface of the gear box is also calculated. Sound power of the gear box is larger in the case that bearings have offset to the wall of the gear box than that bearings are on the center of the gear box. The sound power increases with the augmentation of the offset.

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Vibration Analysis of Structure with Nonlinear Joint Using Describing Function (기술함수를 이용한 비선형 결합부를 가진 구조물의 진동해석)

  • 박해성;지태한;박영필
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.2
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    • pp.372-379
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    • 1994
  • In this study, the describing function is adopted to represent nonlinearity in the system equations. The compliance can be obtained by solving nonlinear simultaneous algebraic quations for multi-degrees-of-freedom system with multinonlinearities. When the technique is applied, the nonlinearity of the system can be identified from the compliance which is obtained from the sinusoidal excitation of the system. By employing the describing function in the Building Block Analysis, we can extensively develop the BBA into investigation of the continuous systems with nonlinearities. The evaluated compliance can quantitatively show the effects of nonlinearity such as the transfer of the natural frequency, the variance of the compliance at the natural frequency, and the jump phenomena which occur during sweeping of the excitation frequency.

The Listing Procedure for Plant Strengtheners in Germany (독일의 식물강화제 목록공시 제도)

  • Lee, Sang-Beom;Lee, Hyo-Won;Choi, Kyeong-Ju
    • Proceedings of the Korean Society of Organic Agriculture Conference
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    • 2009.12a
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    • pp.277-278
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    • 2009
  • 독일 연방작물보호법(PflSchG-Gesetz zum Schutz der Kulturpflanzen, 1986.9. 15 제정)은 식물강화제(한국의 친환경유기농자재와 동일)에 대한 정의를 3가지로 대별하여 명시하고 연방농림생물학청(BBA)에 신고를 의무화하도록 개정(1998.7. 27)하여 법률적인 근거를 마련하였다. 정부조직 개편으로 인하여 2002년 11월 1일부터 연방소비자보호 및 식품안전청(BVL)에서 유기농자재 등록 허가 업무를 주관하고 있다. 식물강화제는 작물보호법에 의하여 허가되는 농약, 생장촉진제, 작물보조제 및 비료관리법(Dungemittelgesetz)에 의한 식물영양제, 식물보조제, 작물재배 배양토 및 토양개량제 등과는 차별화하여 명시하고 있다. 식물강화제는 독일 작물보호법(PflSchG-Gesetz zum Schutz der Kulturpflanzen; Plant Protection Act) 제1장 제2조 10항에 의거하여 (1)유해생물에 대한 저항력을 높여주는 물질, (2)비기생성 피해에 대하여 식물을 보호해 주는 물질, (3)재배작물 이외의 잘려진 관상식물에 사용되는 물질로 정의하고 있다. 이러한 법률적 정의의 요지는 인간과 동물의 건강 및 자연계에 해로운 영향이 없으면서 식물체에 유해한 생물에 대하여 저항성만을 높여주는 물질을 말하며, 기상 및 환경공해 등에 의한 장해도 유해생물에 의한 것과 동일하게 간주되며 이에 대한 저항성을 높여 주는 물질도 포함시키고 있다. 식물강화제는 원칙적으로 유해생물 방제에 직접적으로 작용시키기 위한 이용목적으로 사용할 수 없으며, 단지 작물의 저항성을 높이는 경우에 한하여야 사용된다. 식물강화제의 등록 허가신청은 생산자, 판매업자 또는 수입업자가 연방소비자보호 및 식품안전청(BVL)에 신청하여야 한다. 이렇게 신청된 식물강화제는 작물보호법 제2조에 의거하여 이루어진다. 연방소비자보호 및 식품안전청의 작물보호제의 관리부서는 특별한 문제가 없는 한 4개월 이내에 등록을 허가하고 목록을 홈페이지에 목록을 공시한다. 목록공시는 통상적으로 매월 초순에 1회 게시된다. 허가 등록 절차는 맨처음 서류가 접수되면 구비서류가 완전한지 여부를 검토하여 신청서류에 문제가 없으면 4부를 복사하여 연방소비자보호 및 식품안전청(BVL, Federal Office of Consumer Protection and Food Safety), 환경청(UBA, Federal Environment Agency), 연방농림생물학청(BBA, Federal Biogical Research Centre for Agriculture and Forestry) 및 위해성평가연구소(BfR, Fedral Institute for Risk Assessment)에 우편으로 해당부서에 발송한다. 4개 기관이 검토한 내용이 서로 상이한 판단을 하였을 경우 연방소비자보호 및 식품안전청은 등록 허가결정을 하기 전에 "전문가위원회"를 개최하여 의견을 청취한다. 전문위원회는 연방농림생물청, 환경부, 위해성평가연구소 연구원 등 작물, 독성 및 환경보호 전문가 25인으로 구성되어있다. 연방소비자보호 및 식품안전청의 작물보호 제2부서(식물강화제 검토부서)는 전문위원과 검토기관의 의견을 종합하여 자체적으로 등록 허가 여부를 결정하여 제품 신청자에게 결정 내용을 통보함으로서 등록절차가 마무리 된다. 독일의 식물강화제, 즉 유기농자재는 국가에서 허가한 제품에 한하여 유기농업연구소(FiBL)에서 허용목록 책자를 만들어 유기농업단체 제공하면 단체에 따라 사용가능 유기농자재 제품을 다시 선별하여 회원에게 알려준다. 2009년 11월 30일 현재 독일의 연방소비자보호 및 식품안전청(BVL)에서 허가 공시한 식물강화제는 490개 제품에 이르고 있다.

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Development of Experimental Dynamic Modification Technique for Mounted System (마운트계의 실험적 변경설계법의 개발)

  • 정의봉;조영희
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1996.10a
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    • pp.351-356
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    • 1996
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Blood-Blister Aneurysms of the Internal Carotid Artery in Tibetan and Han Populations : A Retrospective Observational Study

  • Bowen Huang;Yanming Ren;Hao Liu;Anqi Xiao;Lunxin Liu;Hong Sun;Yi Liu;Hao Li;Lu Ma;Chang-Wei Zhang;Chao-Hua Wang;Min He;Yuekang Zhang;Chao You;Jin Li
    • Journal of Korean Neurosurgical Society
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    • v.67 no.3
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    • pp.345-353
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    • 2024
  • Objective : Blood-blister aneurysms (BBAs) of the internal carotid artery (ICA) are challenging lesions with high morbidity and mortality rates. Although research on BBAs is well documented in different populations, the study of BBAs in the Tibetan population is extremely rare. This study aimed to evaluate the characteristics of BBAs and analyze the treatment modalities and long-term outcomes in the Tibetan population in comparison with the Han population. Methods : The characteristics of patients with BBAs of the ICA from January 2009 to January 2021 at our institution were reviewed. The features of aneurysms, treatment modalities, complications, and follow-up outcomes were retrospectively analyzed. Results : A total of 130 patients (41 Tibetan and 89 Han patients) with BBAs of the ICA who underwent treatment were enrolled. Compared with the Han group, the Tibetan group significantly demonstrated a high ratio of BBAs among ICAs (8.6%, 41/477 vs. 1.6%, 89/5563; p<0.05), a high ratio of vasospasm (34.1%, 14/41 vs. 6.7%, 6/89; p=0.001), a high risk of ischemic events (43.9%, 18/41 vs. 22.5%, 20/89; p<0.05), and a low ratio of good outcomes (modified Rankin scale, 0-2) at the 1-year follow-up (51.2%, 21/41 vs. 74.2%, 66/89; p<0.05). The multivariate regression model showed that ischemic events significantly contributed to the prediction of outcomes at 1 year. Further analysis revealed that microsurgery and vasospasm were associated with ischemic events. Conclusion : In comparison with Han patients, the Tibetan population had a high ratio of BBA occurrence, a high incidence of ischemic events, and a high ratio of poor outcomes. The endovascular approach showed more benefits in BBA patients.

A Bandwidth a Allocation Scheme based on Bankruptcy theory in Distributed Mobile Multimedia Network (분산 모바일 멀티미디어 통신망에서 파산이론을 적용한 대역폭 할당기법)

  • Jeong, Seong Soon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.4
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    • pp.246-251
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    • 2013
  • In this paper, it is proposed a bandwidth allocation Scheme based on Bankruptcy theory in Distributed Mobile Multimedia Network. The proposed scheme is guaranteed a minimum allocation. So, the minimum quality of each service are guaranteed. Therefore efficient and fairness network can be configured. The performance evaluation results indicate that the proposed scheme has good performance than other existing schemes by the fairness index and the Erlang blocking formular calculation. The minimum bandwidth of the proposed scheme can be applied to other techniques of a priority based bandwidth allocation scheme and dynamic bandwidth allocation scheme.

Mass Spectrometric Determination of Zn2+ Binding/Dissociation Constant for Zinc Finger Peptides

  • Lee, Choong Sik;Park, Soo Jin;Lee, Jae Young;Park, Sungsu;Jo, Kyubong;Oh, Han Bin
    • Mass Spectrometry Letters
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    • v.6 no.1
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    • pp.7-12
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    • 2015
  • In the present study, we proposed a simple ESI-MS model for determining $Zn^{2+}$ binding (or dissociation) constants for zinc finger peptides (ZFPs) with a unique ${\beta}{\beta}{\alpha}$ fold consensus. The ionization efficiency (response) factors for this model, i.e., ${\alpha}$ and ${\beta}$, could be determined for ZiCo ZFP with a known $Zn^{2+}$ binding constant. We could determine the binding constants for other ZFPs assuming those with a ${\beta}{\beta}{\alpha}$ consensus conformation have the same ${\alpha}/{\beta}$ response ratio. In general, the ZPF dissociation constants exhibited $K_d$ values of $10^{-7}{\sim}10^{-9}M$, while $K_d$ values for a negative control non-specific $Zn^{2+}$ peptides were high, e.g., $5.5{\times}10^{-6}M$ and $4.3{\times}10^{-4}M$ for BBA1 and melittin, respectively.