• Title/Summary/Keyword: Back bias

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Analysis of Recent Research Trends in Thread Embedding Acupuncture for Low Back Pain

  • Yae Gi Min;Hyang Gi Lim;Hyun Jong Lee;Jung Hee Lee;Sung Chul Lim;Yun Kyu Lee;Jae Soo Kim
    • Journal of Acupuncture Research
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    • v.41 no.2
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    • pp.96-106
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    • 2024
  • This study aimed to provide the basis of treatment effects by analyzing randomized control trials (RCTs) on the use of thread embedding acupuncture (TEA) for low back pain that were published between February 2018 and July 2023. In total, 2,865 articles were retrieved from international and Korean databases. Nine of these articles were selected and evaluated based on the following categories: (1) year of publication, (2) type of disease, (3) sample size, (4) treatment interventions, (5) treatment frequency and duration, (6) insertion point and depth of thread embedding, (7) types and sizes of threads and needles, (8) evaluation indexes, (9) treatment outcomes, and (10) side effects. The risk of bias in RCTs was also assessed. This study also emphasizes the importance of further research on TEA for clinical treatment and the use of objective approaches. Furthermore, detailed method descriptions and results are important in determining the efficacy of TEA.

Reviews and Proposals of Low-Voltage DRAM Circuit Design (저전압 DRAM 회로 설계 검토 및 제안)

  • Kim, Yeong-Hui;Kim, Gwang-Hyeon;Park, Hong-Jun;Wi, Jae-Gyeong;Choe, Jin-Hyeok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.38 no.4
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    • pp.251-265
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    • 2001
  • As the device scaling proceeds, the operating voltage(VDD) of giga-bit DRAMs is expected to be reduced to 1.5V or down, fir improving the device reliability and reducing the power dissipation. Therefore the low-voltage circuit design techniques are required to implement giga-bit DRAMs. In this work, state-of-art low-voltage DRAM circuit techniques are reviewed, and four kinds of low-voltage circuit design techniques are newly proposed for giga-bit DRAMs. Measurement results of test chips and SPICE simulation results are presented for the newly proposed circuit design techniques, which include a hierarchical negative-voltage word-line driver with reduced subthreshold leakage current, a two-phase VBB(Back-Bias Voltage) generator, a two-phase VPP(Boosted Voltage) generator and a bandgap reference voltage generator.

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Design of a 512b Multi-Time Programmable Memory IPs for PMICs (PMIC용 512비트 MTP 메모리 IP설계)

  • Jang, Ji-Hye;Ha, Pan-Bong;Kim, Young-Hee
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.9 no.1
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    • pp.120-131
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    • 2016
  • In this paper, a 512b MTP memory IP is designed by using MTP memory cells which are written by the FN (Fowler-Nordheim) tunneling method with only MV (medium voltage) devices of 5V which uses the back-gate bias, that is VNN (negative voltage). The used MTP cell consists of a CG (control gate) capacitor, a TG (tunnel gate) transistor, and a select transistor. To reduce the size of the MTP memory cell, just two PWs (P-wells) are used: one for the TG and the select transistors; and the other for the CG capacitor. In addition, just one DNW (deep N-well) is used for the entire 512b memory cell array. VPP and VNN generators supplying pumping voltages of ${\pm}8V$ which are insensitive to PVT variations since VPP and VNN level detectors are designed by a regulated voltage, V1V (=1V), provided by a BGR voltage generator.

A Comparative Study of Tight Skirt Sewing Methods -Focusing on the Sewing Methods Shown in Reference Text Books on Clothing Configuration and used in Domestic Consumer Products- (타이트스커트 봉제방법에 관한 비교 연구 -의복구성 교재와 국내 브랜드 제품을 중심으로-)

  • Kim, Sun-Young;Choi, Young-Soon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.31 no.11
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    • pp.1510-1519
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    • 2007
  • This comparative study analyzes and compares tight skirt sewing methods which are found in the clothing configuration reference text books available in contemporary universities and which are used in commercially-available domestic consumer products. The study samples included 15 text books and 12 tight skirt consumer products of different brands on sale at three department stores in Seoul each of which had a belt, a back-centered zipper, and back double slits. The findings of the study are summarized as follows: First, text books mainly show very basic sewing methods of using zippers on both sides of the straight-lined waist belt. This indicates that it is necessary for such methods to be complemented so that they cover a recent variety of designs, materials, and sewing machines. For consumer products, the main sewing method is to use a curved waist belt and a console zipper in silhouette running across half the hipbone. Second, consumer products employ three different types of cutting and sewing methods for putting an inseam on the center of the back slit part: to leave the whole inseam hemmed in the back center, to cut the left side of the inseam to the upper part of the back slit, and to cut the inseam to both the upper parts of the back slit. However, a method shown in most of the sampled text books is to cut the inseam of the back center to both the upper parts of the back slit. Third, the way of finishing a bottom edge hem in the text books is to do slip-stitch, herringbone stitch, and slinting hemming, in order after doing over-lock stitch, or to cut the hem on the bias and then slip-stitch, while for the consumer products the most frequently used sewing method is to finish the bottom edge hem by doing secoui-stitch. Finally, while in the text books the method of stitching darts and tucks is used for lining, the main lining method used in consumer products is to make tucks only. Also in the way of stitching the side seams of lining or the seams of the back center, there is a difference between the two sample groups of text books and the consumer products: while the former suggests using both open seams and over-lock stitch, the latter is found to finish the seams using an over-lock stitch only.

Comparison of Reliability Estimation Methods for Ammunition Systems with Quantal-response Data (가부반응 데이터 특성을 가지는 탄약 체계의 신뢰도 추정방법 비교)

  • Ryu, Jang-Hee;Back, Seung-Jun;Son, Young-Kap
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.6
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    • pp.982-989
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    • 2010
  • This paper shows accuracy comparison results of reliability estimation methods for one-shot systems such as ammunitions. Quantal-response data, following a binomial distribution at each sampling time, characterizes lifetimes of one-shot systems. Various quantal-response data of different sample sizes are simulated using lifetime data randomly sampled from assumed weibull distributions with different shape parameters but the identical scale parameter in this paper. Then, reliability estimation methods in open literature are applied to the simulated quantal-response data to estimate true reliability over time. Rankings in estimation accuracy for different sample sizes are determined using t-test of SSE. Furthermore, MSE at each time, including both bias and variance of estimated reliability metrics for each method are analyzed to investigate how much both bias and variance contribute the SSE. From the MSE analysis, MSE provides reliability estimation trend for each method. Parametric estimation method provides more accurate reliability estimation results than the other methods for most of sample sizes.

A Study on Draping and Making up of Spencer Jacket in the Empire Style(1789-1820) (엠파이어 스타일 시대[1789-1820] 스펜서 재킷 제작에 관한 연구)

  • Choi Mi-Kyung;Jo Jin-Sook;Choi Jin-Hee
    • Journal of the Korean Society of Costume
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    • v.56 no.4 s.103
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    • pp.48-64
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    • 2006
  • The purpose of the study was to demonstrate how to recreate spencer jacket in the empire style in an attempt to apply this historic style to theatrical costumes and other high fashion items in modern times. The study was carried out through 2 steps. (1)Block patterns of spencer jacket of its basic design were developed through draping based on the design characteristics mentioned above. (2)Spencer jackets of three designs, which were the typical designs of each category have been made of velvet to find out more specific structural characteristics. The structural characteristics of Spencer jacket in draping were as follows: (1)Jacket length position was suitable 9cm below body's bust line and neckline should be enlarged front & side neck point 2cm, back neck point 1.5cm. (2)Cut out the front bodice after CF line moved 1cm outwards and bust dart amount should not exceed 2-3cm. Shoulder point moved inwards. (3)Side back grain line was parallel to princess line of the back bodice. Add 0.5cm ease to the under arm of the front and side bark bodice, it was good for the activity of arm. (4)Armhole line was trued as maintaining to across back width 14-15cm at least. Shoulder line was to connect from the point 2cm depart shoulder point along armhole line to point 2cm side neck point along neck line. (5)Sleeve length was suitable 70cm, cut out the bias direction to move forwards the grain line from shoulder point. Puff position was good from the 2cm depart shoulder point to shoulder line.

Compact T/R Module Having Improved T/R Isolation Using a Bias Timing Scheme (바이어스 타이밍 기법을 이용하여 송수신 격리도가 개선된 소형 송수신 모듈)

  • Park, Sung-Kyun;Lee, Hai-Young
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.23 no.12
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    • pp.1380-1387
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    • 2012
  • The transmit/receive(T/R) module is a key component in the active phased array system. The brick-type T/R module has been widely used and the miniaturization has been an important factor to get the flexibility of the system configuration. For the miniaturization, multi-function chips(MFC) having a common leg configuration are suitable to reduce the number of required MMICs and a high isolation between transmit and receive paths is necessary for the high gain T/R modules. In this work, we propose a bias timing scheme for the compact T/R module and show the optimum timing based on measurements, in order to improve the feed-back path loop problem and the consequent isolation problem of the common leg configuration. We have implemented high power(7 W/channel) and high T/R gain(35 dB transmit and 30 dB receive gains) within the half size($140{\times}80{\times}16mm^3$) of the conventional T/R modules.

Korean Medicine for Thoracolumbar Compression Fracture in Korean Literature : a Systematic Review (흉요추 압박 골절의 한의학적 치료에 대한 국내 임상 근거 : 체계적 문헌 고찰)

  • Bae, Ji Min;Kim, Dae Hun;Kim, Jae Kyu;Lee, Byung Ryul;Yang, Gi Young;Kim, Kun Hyung
    • Journal of Acupuncture Research
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    • v.32 no.4
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    • pp.147-156
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    • 2015
  • Objectives : This study aims to evaluate the effectiveness and safety of Korean medicine for a thoracolumbar compression fracture. Methods : We searched six Korean databases (DBPIA, Korean Studies Information Service System, Oriental Medicine Advanced Searching Integrated System, National Digital Science Library, Research Information Sharing Service, KoreaMed) (up to June 2015) and the Journal of Korean Acupuncture and Moxibustion Society. Unpublished studies were also searched. Clinical research, other than case reports involving less than 10 patients, were eligible. The effectiveness and safety of Korean Medicine was analyzed. The 'Risk of Bias' was assessed using the 'Risk of Bias' assessment tool for non-randomized studies as well as the Cochrane Collaboration's 'Risk of Bias' tool. Results : We found 12 before-after studies (374 patients). There was no randomized trial. All studies combined at least three different types of Korean medicine treatments. The period of treatment varied between less a week and 154 days. All the included studies reported improvements in pain, functional disability related to lower back pain, global assessment, and benefits in the compression ratio of a fractured vertebrae and skin temperature measured by digital infrared thermal imaging in comparison with the baseline. However, all studies had a high risk of bias and three studies reported mild adverse events. Conclusions : There is no randomized trial for the role of Korean medicine for patients with a thoracolumbar compression fracture. The effectiveness and safety of Korean medicine for this population remains unclear. Findings in this review are seriously biased due to observational design and a high risk of bias included in the studies. Future high-quality randomized trials are warranted.

Reliability and Validity of the Side-lying Instability and Prone Instability Tests in Patients with Lumbar Segmental Instability

  • Kim, Bo-Eon;Lee, Kwan-Woo;Park, Dae-Sung
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.1
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    • pp.1-7
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    • 2021
  • PURPOSE: The purpose of this study is to conduct inter-rater and intra-rater reliability tests in patients with low back pain (LBP) using the prone instability test (PIT) and side-lying instability test (SIT). We have analyzed the Korean version Oswestry disability index (K-ODI) correlations and radiograph finding (RF) for validity. METHODS: Individuals (n = 51) (mean age of 40.27 ± 13.28) with LBP for at least over a week were recruited, together with two participating physical therapist examiners. The measurement consisted of PIT, PST, K-ODI, and RF. Sensitivity (Sn), specificity (Sp), positive predictive value, negative predictive value, prevalence index, agreement %, Cohen's kappa, and prevalence-adjusted bias-adjusted kappa (PABAK) were calculated. The PIT and SIT were compared with RF for validity analysis, while PIT, SIT, K-ODI, and RF were calculated for the correlation analysis. RESULTS: The intra-rater reliability test measured for the PIT (kappa = .79, PABAK = .88) and SIT (kappa = .73, PABAK = .84), and inter-rater reliability test measured for the SIT (kappa = .80, PABAK = .88) showed good agreements. The PIT (Sn = .65, Sp = .63) and SIT validities (Sn = .68, Sp = .70) were compared with RF, showing a significant correlation in PIT and RF (r = .69), SIT and RF (r = .73), and PIT and K-ODI (r = .53). CONCLUSION: The SIT is a more comfortable position test than the PIT in patients. Both PIT and SIT have acceptable reliability and validity.

Gate-Bias Control Technique for Envelope Tracking Doherty Power Amplifier (Envelope Tracking 도허티 전력 증폭기의 Gate-Bias Control Technique)

  • Moon, Jung-Hwan;Kim, Jang-Heon;Kim, Il-Du;Kim, Jung-Joon;Kim, Bum-Man
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.8
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    • pp.807-813
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    • 2008
  • The gate-biases of the Doherty power amplifier are controlled to improve the linearity performance. The linearity improvement mechanism of the Doherty amplifier is the harmonic cancellation of the carrier and peaking amplifier at the output power combining point. However, it is difficult to cancel the harmonic power for the broader power range because the condition for cancelling is varied by power. For the linearity improvement, we have explored the linearity characteristic of the Doherty amplifier according to the input power and gate biases of the carrier and peaking amplifier. To extend the region of harmonic power cancellation, we have injected the proper gate bias to the carrier and peaking amplifier according to the input power levels. To validate the linearity improvement, the Doherty amplifier is designed using Eudyna 10-W PEP GaN HEMT EGN010MKs at 2.345 GHz and optimized to achieve a high linearity and efficiency at an average output power of 33 dBm, backed off about 10 dB from the $P_{1dB}$. In the experiments, the envelope tracking Doherty amplifier delivers a significantly improved adjacent channel leakage ratio performance of -37.4 dBc, which is an enhancement of about 2.8 dB, maintaining the high PAE of about 26 % for the WCDMA 1-FA signal at an average output power of 33 dBm. For the 802.16-2004 signal, the amplifier is also improved by about 2 dB, -35 dB.