• Title/Summary/Keyword: Double stage

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A Novel Third-Order Cascaded Sigma-Delta Modulator using Switched-Capacitor (스위치형 커패시터를 이용한 새로운 형태의 3차 직렬 접속형 시그마-델타 변조기)

  • Ryu, Jee-Youl;Noh, Seok-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.1
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    • pp.197-204
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    • 2010
  • This paper proposes a new body-effect compensated switch configuration for low voltage and low distortion switched-capacitor (SC) applications. The proposed circuit allows rail-to-rail switching operation for low voltage SC circuits and has better total harmonic distortion than the conventional bootstrapped circuit by 19 dB. A 2-1 cascaded sigma-delta modulator is provided for performing the high-resolution analog-to-digital conversion on audio codec in a communication transceiver. An experimental prototype for a single-stage folded-cascode operational amplifier (opamp) and a 2-1 cascaded sigma-delta modulator has been implemented m a 0.25 micron double-poly, triple-metal standard CMOS process with 2.7 V of supply voltage. The 1% settling time of the opamp is measured to be 560 ns with load capacitance of 16 pF. The experimental testing of the sigma-delta modulator with bit-stream inspection and analog spectrum analyzing plot is performed. The die size is $1.9{\times}1.5\;mm$.

A Wideband Down-Converter for the Ultra-Wideband System (초광대역 무선통신시스템을 위한 광대역 하향 주파수 변환기 개발에 관한 연구)

  • Kim Chang-Wan;Lee Seung-Sik;Park Bong-Hyuk;Kim Jae-Young;Choi Sang-Sung;Lee Sang-Gug
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.2 s.93
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    • pp.189-193
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    • 2005
  • In this paper, we propose a direct conversion double-balanced down-converter fer MB-OFDM W system, which is implemented using $0.18\;{\mu}m$ CMOS technology and its measurement results are shown. The proposed down-converter adopts a resistive current-source instead of general transconductance stage using MOS transistor to achieve wideband characteristics over RF input frequency band $3\~5\;GHz$ with good gain flatness. The measured conversion gain is more than +3 dB, and gain flatness is less than 3 dB for three UWB channels. The dc consumption of this work is only 0.89 mA from 1.8 V power supply, leading to the low-power W application.

A Review of Acupuncture for the Treatment of Raynaud's Disease (레이노병의 침치료에 대한 연구동향)

  • Jeon, Sang-woo;Kim, Ho;Jeong, Min-jeong;Jang, In-soo
    • The Journal of Internal Korean Medicine
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    • v.38 no.4
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    • pp.433-442
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    • 2017
  • Objectives: The purpose of this study was to assess the effectiveness of acupuncture for the treatment of Raynaud's disease. Methods: This review was conducted using nine electronic databases (CINAHL, CiNii, CNKI, EMBASE, J-STAGE, NDSL, OASIS, PubMed, and WANFANG) and the keywords "Raynaud's disease", "Raynaud disease", "acupuncture", and "needling". Only randomized controlled trials (RCTs) using acupuncture for Raynaud's disease were included, and the methodological quality of the trials was assessed using the Cochrane risk-of-bias tool. Results: After screening, six RCTs were selected among 67, and the total effective rate and peripheral blood flow were used as evaluation methods. In five studies, the total effective rate was significantly higher in the intervention group than in the control group. In three studies, peripheral blood flow was higher in the intervention group than in the control group, with two studies being statistically significant and the remaining study not being statistically significant. Conclusions: Acupuncture could be a suitable treatment without adverse effects for Raynaud's disease because it improves peripheral blood flow. However, further studies, including randomized, placebo-controlled, double-blind methods, and clear evaluation criteria are needed.

Rapid in vitro Germination of Zygotic Embryos via Endosperm Removal in Eleutherococcus senticosus

  • You Xiang-Ling;Choi Yong-Eui;Yi Jae-Seon
    • Journal of Plant Biotechnology
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    • v.7 no.1
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    • pp.75-80
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    • 2005
  • Eleutherococcus senticosus (also called Acanthopanax senticosus), belonging to Araliaceae family, has been used as an important medicinal woody plant. Mature seeds of Eleutherococcus senticosus have rudimentary (extremely immature) zygotic embryos and require a long-term stratification for about 18 months to induce germination. Here, through the methods of endosperm removal and other exogenous treatments, we investigated the factors for inducing rudimentary embryos by in vitro culture, Rudimentary zygotic embryos in seeds were at globular to heart-shaped stage at about $250{\mu}m$ in length just after harvest of fruits. When the seeds without testa were cultured on 1/2 MS (Murashige and Skoog 1962) medium, they did not germinate regardless of medium and sucrose concentrations but the removal of endosperm tissue markedly stimulated the growth of rudimentary zygotic embryos. The embryo reached ear-lier maturation, once when the endosperm surrounding the rudimentary embryos was removed. Rudimentary zygotic embryos developed cotyledons within 3 weeks of culture after endosperm emoval. However, post-mature zygotic embryos failed to germinate though they were morphologically normal, indicating another dormancy of embryos. $GA_3\;(2.0\;\cal{mg/L})$ and/or charcoal ($0.2\%$) treatment rapidly enhanced the germination of zygotic embryos. These results suggest that E. senticosus seeds have double dormancy; i. e. morphological rudimentary dormancy influenced by surrounding endosperm and physiological dormancy after post-maturation of zygotic embryos. Based on the above findings, we established the rapid germination of rudimentary zygotic embryos by in vitro culture of excised seeds with endosperm removal and $GA_3$ treatment.

Master Packaging System of Fresh Produce (신선 농산물의 마스터 포장 시스템)

  • Lee, Dong Sun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.20 no.1
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    • pp.1-6
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    • 2014
  • Properly designed plastic packages of fresh produce can preserve the quality by maintaining the optimal modified atmosphere (MA) at optimal low temperature conditions, but cannot do so at temperature abuse conditions in retail stage due to occurrence of injurious package atmosphere coming from imbalance between respiration and package gas permeation. Master packaging system consisting of a double-layered secondary package wrapping several individual (primary) packages has been proposed and applied recently to the commodities of sweet persimmon, king oyster mushroom, chestnut and strawberry. The master (secondary) pack is designed to be stored and distributed under chilled temperature, and then dismantled when moved to the retail display from the presale chilled storage. The master packaging system taking into consideration temperature dependence of produce respiration and package gas transfer was looked into with examination of its design variables to maintain the beneficial MA. Mathematical model was provided to help the design of master packaging system creating the desired MA. Its benefits of quality preservation and its limitations in practices of fresh produce marketing were discussed. Further research direction to extend the applicability of the produce master packaging system was presented.

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Prevalence and Clinical Profile of EGFR Mutation In Non-Small-Cell Lung Carcinoma Patients in Southwest China

  • Zhou, Juan;Song, Xing-Bo;He, He;Zhou, Yi;Lu, Xiao-Jun;Ying, Bin-Wu
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.965-971
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    • 2016
  • Aims: To investigate the distribution of epidermal growth factor receptor (EGFR) mutations, and explore any relationships with clinical characteristics in non-small-cell lung carcinoma (NSCLC) patients. Materials and Methods: EGFR mutations were assessed by ADx-ARMS in 261 NSCLC patients from West China Hospital of Sichuan University. Relationships between EGFR mutation and clinical characteristics were analyzed by SPSS. Results: The EGFR mutation rate was 48.7% (127/261), 19-del and L858R mutations occurred predominantly, accounting for 33.1% and 40.9%, respectively, in mutated cases. Moreover, 10.2% patients were found to carry double mutations. EGFR mutations occurred more frequently in women (57.5%) than in men (41.8%) (P=0.01), and were more frequent in non-smokers (61.2%) than in former or current smokers (31.2%) (P<0.00). In addition, they were more common in adenocarcinomas (52.8%) and adenosquamous carcinomas (42.8%) than in squamous cell carcinomas (14.8%) (p<0.00). However, only smoking history and pathological types, rather than gender, proved to be associated with EGFR mutations on multivariate logistic regression analysis. No significant differences in pathological stage and metastasis status were found between EGFR wild-type and mutated cases, although EGFR mutation type was related to pathological type (p=0.00) - 19-del, L858R and other mutation types respectively occurred in 34.2%, 42.5% and 23.3% of adenocarcinomas, but in 14.3%, 0% and 85.7% of non-adenocarcinomas. Conclusions: The EGFR mutation rate was 48.7% in NSCLCs in Southwest China, so that nearly 40% patients might benefit from targeted therapies. Smoking status and pathological types were independent predictors of EGFR mutation, while EGFR mutation type was related to only pathological type, rather than smoking status.

Prospect of new variety breeding of Italian ryegrass in South Korea

  • Ji, Hee Chung;Hwang, Tae Young;Lee, Ki Won
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.108-108
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    • 2017
  • The objective of this study was to know prospect and present state of new variety breeding of Forage and Grassland in South Korea. The industry of forage in Korea is going up to expend through utilization of good quality forage, Italian ryegrass, forage corn and oat rather than rice straw. Especially, since 2007, Italian ryegrass(IRG) had been very important major winter forage crop in South Korea and developed 13 varieties including very early maturity variety (three varieties), early maturity variety (three varieties), medium maturity variety (one variety) and late maturity variety (six varieties). But the disadvantage of Italian ryegrass was weak winter hardness and drought but has good advantage of forage nutritive value, high-yielding and high sugar content, and like livestock as like hanwoo, dairy cattle, goat so on. The Ko-variety (Korea developed variety) of Italian ryegrass has high cold-tolerant and adaptability more than any other country developed variety, and expend to cultivation area from southern area (below Daejeon) to middle-northern area (upper Han river). Although the cultivation area of Italian ryegrass of South Korea was 21,700 ha in 2007, right now, that of Italian ryegrass is about 123,600ha due to expend cultivation area and know famer to good forage crop and have a various maturity varieties (very early, early, medium, late) according to local situation (before-crop harvesting stage or double cropping system). The seed market of Italian ryegrass in South Korea becoming extended to around 100 million Korean won and seed export get nearer to foreign country. We are going to develop of new variety for stress tolerant and high yield and quality forage variety, good adaptability to the Korean environmental conditions including reclaimed area, make self-sufficiency system for forage seed (Italian ryegrass), export our seed to foreign countries.

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A Research for the Noise Development of the FF 8th Speed Automatic Transmission (전륜 8속 자동변속기 소음 개발에 대한 연구)

  • Lee, Hyun Ku;Hong, Sa Man;Kim, Moo Suk;Hur, Jin Wook;Yoo, Dong Kyu
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.26 no.5
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    • pp.559-566
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    • 2016
  • This study shows a development procedure and results of noise reduction for a new developed FF 8th speed automatic transmission. Based on planetary gear operating frequency analysis using PTA(planetary transmission analysis) program developed in 2012, It is expected that gear noise of the rear planetary gear set could be recognized easily in the concept design stage. Therefore, pRMC (planetary run many cases) analysis program that is developed in 2012 was applied to minimize the planetary gear noise level and noise distributions versus torque. To minimize noises coming from oil pump and final gears of a new transmission, several changes were applied, such as changing the clearance of double angular ball bearing, the oil pump rotor tooth number from 9 to 11 and the oil pump type from parachoid to megafloid and so on. Besides, stiffness values of the transmission case and the mount bracket were measured and reinforced properly. Finally, The total noise of the new FF 8th speed automatic transmission was developed successfully. Furthermore, E.O.L. testers also have been adapted to control the noise quality of automatic transmission assembly in the manufacturing factory. This paper could provide practical solutions to the automatic transmission NVH problems.

Design and Implementation of Conversion System Between ISO/IEC 10646 and Multi-Byte Code Set (ISO/IEC 10646과 멀티바이트 코드 세트간의 변환시스템의 설계 및 구현)

  • Kim, Chul
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.4
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    • pp.319-324
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    • 2018
  • In this paper, we designed and implemented a code conversion method between ISO/IEC 10646 and the multi-byte code set. The Universal Multiple-Octet Coded Character Set(UCS) provides codes for more than 65,000 characters, huge increase over ASCII's code capacity of 128 characters. It is applicable to the representation, transmission, interchange, processing, storage, input and presentation of the written form of the language throughout the world. Therefore, it is so important to guide on code conversion methods to their customers during customer systems are migrated to the environment which the UCS code system is used and/or the current code systems, i.e., ASCII PC code and EBCDIC host code, are used with the UCS together. Code conversion utility including the mapping table between the UCS and IBM new host code is shown for the purpose of the explanation of code conversion algorithm and its implementation in the system. The programs are successfully executed in the real system environments and so can be delivered to the customer during its migration stage from the UCS to the current IBM code system and vice versa.

Spade-Shaped Anastomosis Following a Proximal Gastrectomy Using a Double Suture to Fix the Posterior Esophageal Wall to the Anterior Gastric Wall (SPADE Operation): Case-Control Study of Early Outcomes

  • Han, Won Ho;Eom, Bang Wool;Yoon, Hong Man;Ryu, Junsun;Kim, Young-Woo
    • Journal of Gastric Cancer
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    • v.20 no.1
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    • pp.72-80
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    • 2020
  • Purpose: Proximal gastrectomy (PG) is a function-preserving surgery in cases of proximally located early-stage gastric cancer. Because gastroesophageal reflux is a major pitfall of this operation, we devised a modified esophagogastrostomy (EG) anastomosis to fix the distal part of the posterior esophageal wall to the proximal part of the anterior stomach wall to produce an anti-reflux mechanism; we named this the SPADE operation. This study aimed to show demonstrate the clinical outcomes of the SPADE operation and compare them to those of previous PG cases. Materials and Methods: Case details of 56 patients who underwent PG between January 2012 and March 2018 were retrospectively reviewed: 30 underwent conventional esophagogastrostomy (CEG) anastomosis using a circular stapler, while 26 underwent the SPADE operation. Early postoperative clinical outcome-related reflux symptoms, endoscopic findings, and postoperative complications were compared in this case-control study. Results: Follow-up endoscopy showed more frequent reflux esophagitis cases in the CEG group than in the SPADE group (30% vs. 15.3%, P=0.19). Similarly, bile reflux (26.7% vs. 7.7%, P=0.08) and residual food (P=0.01) cases occurred more frequently in the CEG group than in the SPADE group. In the CEG group, 13 patients (43.3%) had mild reflux symptoms, while 3 patients (10%) had severe reflux symptoms. In the SPADE group, 3 patients (11.5%) had mild reflux symptoms, while 1 had severe reflux symptoms (absolute difference, 31.8%; 95% confidence interval, 1.11-29.64; P=0.01). Conclusions: A novel modified EG, the SPADE operation, has the potential to decrease gastroesophageal reflux following a PG.