• Title/Summary/Keyword: two-point threshold

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Positive and negative predictive values by the TOC curve

  • Hong, Chong Sun;Choi, So Yeon
    • Communications for Statistical Applications and Methods
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    • v.27 no.2
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    • pp.211-224
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    • 2020
  • Sensitivity and specificity are popular measures described by the receiver operating characteristic (ROC) curve. There are also two other measures such as the positive predictive value (PPV) and negative predictive value (NPV); however, the PPV and NPV cannot be represented by the ROC curve. Based on the total operating characteristic (TOC) curve suggested by Pontius and Si (International Journal of Geographical Information Science, 97, 570-583, 2014), explanatory methods are proposed to geometrically describe the PPV and NPV by the TOC curve. It is found that the PPV can be regarded as the slope of the right-angled triangle connecting the origin to a certain point on the TOC curve, while 1 - NPV can be represented as the slope of the right-angled triangle connecting a certain point to the top right corner of the TOC curve. When the neutral zone exists, the PPV and 1-NPV can be described as the slopes of two other right-angled triangles of the TOC curve. Therefore, both the PPV and NPV can be estimated using the TOC curve, whether or not the neutral zone is present.

Pressure pain threshold and visual analogue scale changes in the high and low energy extracorporeal shock wave

  • Yang, You-Jin;Lee, Seung-Joon;Choi, Matthew
    • Physical Therapy Rehabilitation Science
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    • v.3 no.2
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    • pp.142-147
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    • 2014
  • Objective: This study aims to investigate high energy and low energy extracorporeal shockwave therapy (ESWT) and which one is more effective for shoulder pain. Design: Single blind randomized controlled trial. Methods: Fifty two subjects with upper trapezius (UT) trigger point (TrP) participated in this study. They were allocated to high energy (n=26) and low energy group (n=26). This study applies ESWT and investigates the changes of pressure pain threshold (PPT) and visual analogue scale (VAS). The high and low energy groups received focused piezo electric type ESWT 4 Hz, 1,000 pulses and 0.351 and $0.092mJ/mm^2$ respectively. Outcome measures of PPT and pain was measured by algometer and pain VAS. These measurements were performed before and after treatment. Results: The PPT value was significantly increased in both groups after treatment (p<0.05) and VAS scores were significantly decreased after treatment in both groups (p<0.05). However, there were no significant differences between groups. Conclusions: ESWT is an effective treatment for the application of the UT TrP. Although there were significant effects of extracorporeal shock wave therapy on PPT and VAS scores, there were no signficant differences between high and low energy extracorporeal shock wave therapy.

DEVELOPMENT OF AN ORTHOGONAL DOUBLE-IMAGE PROCESSING ALGORITHM TO MEASURE BUBBLE VOLUME IN A TWO-PHASE FLOW

  • Kim, Seong-Jin;Park, Goon-Cherl
    • Nuclear Engineering and Technology
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    • v.39 no.4
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    • pp.313-326
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    • 2007
  • In this paper, an algorithm to reconstruct two orthogonal images into a three-dimensional image is developed in order to measure the bubble size and volume in a two-phase boiling flow. The central-active contour model originally proposed by P. $Szczypi\'{n}ski$ and P. Strumillo is modified to reduce the dependence on the initial reference point and to increase the contour stability. The modified model is then applied to the algorithm to extract the object boundary. This improved central contour model could be applied to obscure objects using a variable threshold value. The extracted boundaries from each image are merged into a three-dimensional image through the developed algorithm. It is shown that the object reconstructed using the developed algorithm is very similar or identical to the real object. Various values such as volume and surface area are calculated for the reconstructed images and the developed algorithm is qualitatively verified using real images from rubber clay experiments and quantitatively verified by simulation using imaginary images. Finally, the developed algorithm is applied to measure the size and volume of vapor bubbles condensing in a subcooled boiling flow.

A study on Improvement of sub 0.1$\mu\textrm{m}$VLSI CMOS device Ultra Thin Gate Oxide Quality Using Novel STI Structure (STI를 이용한 서브 0.1$\mu\textrm{m}$VLSI CMOS 소자에서의 초박막게이트산화막의 박막개선에 관한 연구)

  • 엄금용;오환술
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.9
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    • pp.729-734
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    • 2000
  • Recently, Very Large Scale Integrated (VLSI) circuit & deep-submicron bulk Complementary Metal Oxide Semiconductor(CMOS) devices require gate electrode materials such as metal-silicide, Titanium-silicide for gate oxides. Many previous authors have researched the improvement sub-micron gate oxide quality. However, few have reported on the electrical quality and reliability on the ultra thin gate oxide. In this paper, at first, I recommand a novel shallow trench isolation structure to suppress the corner metal-oxide semiconductor field-effect transistor(MOSFET) inherent to shallow trench isolation for sub 0.1${\mu}{\textrm}{m}$ gate oxide. Different from using normal LOCOS technology deep-submicron CMOS devices using novel Shallow Trench Isolation(STI) technology have a unique"inverse narrow-channel effects"-when the channel width of the devices is scaled down, their threshold voltage is shrunk instead of increased as for the contribution of the channel edge current to the total channel current as the channel width is reduced. Secondly, Titanium silicide process clarified that fluorine contamination caused by the gate sidewall etching inhibits the silicidation reaction and accelerates agglomeration. To overcome these problems, a novel Two-step Deposited silicide(TDS) process has been developed. The key point of this process is the deposition and subsequent removal of titanium before silicidation. Based on the research, It is found that novel STI structure by the SEM, in addition to thermally stable silicide process was achieved. We also obtained the decrease threshold voltage value of the channel edge. resulting in the better improvement of the narrow channel effect. low sheet resistance and stress, and high threshold voltage. Besides, sheet resistance and stress value, rms(root mean square) by AFM were observed. On the electrical characteristics, low leakage current and trap density at the Si/SiO$_2$were confirmed by the high threshold voltage sub 0.1${\mu}{\textrm}{m}$ gate oxide.

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Securing Mobile Ad Hoc Networks Using Enhanced Identity-Based Cryptography

  • Mehr, Kamal Adli;Niya, Javad Musevi
    • ETRI Journal
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    • v.37 no.3
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    • pp.512-522
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    • 2015
  • Recent developments in identity-based cryptography (IBC) have provided new solutions to problems related to the security of mobile ad hoc networks (MANETs). Although many proposals to solve problems related to the security of MANETs are suggested by the research community, there is no one solution that fits all. The interdependency cycle between secure routing and security services makes the use of IBC in MANETs very challenging. In this paper, two novel methods are proposed to eliminate the need for this cycle. One of these methods utilizes a key pool to secure routes for the distribution of cryptographic materials, while the other adopts a pairing-based key agreement method. Furthermore, our proposed methods utilize threshold cryptography for shared secret and private key generation to eliminate the "single point of failure" and distribute cryptographic services among network nodes. These characteristics guarantee high levels of availability and scalability for the proposed methods. To illustrate the effectiveness and capabilities of the proposed methods, they are simulated and compared against the performance of existing methods.

A Study on Determination of Frontal QRS Electrical Axis by Minnesota Coding Method (MINNESOTA CODE 분류방식에 의한 전면 QRS 전기축 판정에 관한 연구)

  • Park, Dong-Chan;Lee, Myoung-Ho
    • Proceedings of the KIEE Conference
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    • 1989.11a
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    • pp.421-425
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    • 1989
  • This paper present a algorithm for determination of the frontal QRS axis. Determination of electrical QRS axis helps In the differential diagnosis of wide QRS tachycardia and of hemiblock and In the localization of an accessory pathway. At first detecting R-point data and S-point data and two data is sumed and this data is determind such as positive or negative. Reference data is calculated by 9-point derivertives that is less affected by noise. Secondly, using data of lead2 calculate a morphology, this value is threshold for executing determination algorithm. This process is main body of this algorithm. As this algorithm have a six pattern of the axis that coded by minnesota ending method, the axis is determined more precisely than any other algorithm using 3 leads and affirm a relation of a axis and hemiblock and tachycardia.

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A Probabilistic Algorithm for Multi-aircraft Collision Detection and Resolution in 3-D

  • Kim, Kwang-Yeon;Park, Jung-Woo;Tahk, Min-Jea
    • International Journal of Aeronautical and Space Sciences
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    • v.9 no.2
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    • pp.1-8
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    • 2008
  • This paper presents a real-time algorithm for collision detection, collision avoidance and guidance. Three-dimensional point-mass aircraft models are used. For collision detection, conflict probability is calculated by using the Monte-Carlo Simulation. Time at the closest point of approach(CPA) and distance at CPA are needed to determine the collision probability, being compared to certain threshold values. For collision avoidance, one of possible maneuver options is chosen to minimize the collision probability. For guidance to a designated way-point, proportional navigation guidance law is used. Two scenarios on encounter situation are studied to demonstrate the performance of proposed algorithm.

Convergence of Acupoint and Electrical Stimulation Therapy for Blood Flow and Pain Threshold (혈류량과 통증역치에 대한 경혈과 전기자극치료의 융합연구)

  • Yi, Dong-Hyun;Kim, Beom-Ryong;Hur, Yoon-Jung;Kim, Dong-Hoon;Shim, Su-Young;Yim, Jong-Eun
    • Journal of the Korea Convergence Society
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    • v.10 no.6
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    • pp.79-87
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    • 2019
  • This study examined how the application of silver spike point (SSP) and acupuncture-like transcutaneous electrical nerve stimulation (A-TENS) on acupoints affects blood flow and pain threshold, using laser Doppler blood fluxes and the Commander algometer. Our study included 32 healthy men and women who were randomly divided into the SSP group (n=18) and the A-TENS group (n=14). The pain threshold and blood flow were measured at the Neiguan (PC6) of the Jueyin Pericardium Meridian of the hand. SSP was performed with a 2.8cm electrode at a fixed frequency of 3 Hz for 15 minutes. The change in blood flow and pain threshold after the intervention significantly differed between the two groups (p<0.05). We found that the application of SSP and A-TENS on an acupoint altered their blood flow and pressure pain threshold, with SSP resulting in significantly greater change than A-TENS. Based on these results, the convergence of acupoint and electrical stimulation therapy can be usefully applied as a method for various patients. Continued development of convergence interventions is necessary.

Segmented Douglas-Peucker Algorithm Based on the Node Importance

  • Wang, Xiaofei;Yang, Wei;Liu, Yan;Sun, Rui;Hu, Jun;Yang, Longcheng;Hou, Boyang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.4
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    • pp.1562-1578
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    • 2020
  • Vector data compression algorithm can meet requirements of different levels and scales by reducing the data amount of vector graphics, so as to reduce the transmission, processing time and storage overhead of data. In view of the fact that large threshold leading to comparatively large error in Douglas-Peucker vector data compression algorithm, which has difficulty in maintaining the uncertainty of shape features and threshold selection, a segmented Douglas-Peucker algorithm based on node importance is proposed. Firstly, the algorithm uses the vertical chord ratio as the main feature to detect and extract the critical points with large contribution to the shape of the curve, so as to ensure its basic shape. Then, combined with the radial distance constraint, it selects the maximum point as the critical point, and introduces the threshold related to the scale to merge and adjust the critical points, so as to realize local feature extraction between two critical points to meet the requirements in accuracy. Finally, through a large number of different vector data sets, the improved algorithm is analyzed and evaluated from qualitative and quantitative aspects. Experimental results indicate that the improved vector data compression algorithm is better than Douglas-Peucker algorithm in shape retention, compression error, results simplification and time efficiency.

Pharmacoacupuncture Treatment of Coccygodynia Caused by Perforating Cutaneous Nerve Entrapment Syndrome: Two Cases Report (관통피부신경 포착으로 발생한 꼬리뼈 통증 환자 약침치료 치험 2예)

  • Moon, Sori;An, Sunjoo;Choi, Seonghwan;Park, Seohyun;Keum, Dongho
    • Journal of Korean Medicine Rehabilitation
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    • v.29 no.3
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    • pp.149-156
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    • 2019
  • This study was performed to evaluate the effectiveness of pharmacoacupuncture treatment of coccygodynia caused by perforating cutaneous nerve entrapment syndrome. Two patients were diagnosed as coccygodynia caused by perforating cutaneous nerve entrapment syndrome which pain was within the anatomical field of the nerve, worsened by pressure-inducing posture, no objective sensory loss and in presence of pin-point tenderness. They were treated by pharmacoacupuncture at perforating cutaneous nerve region penertrating the sacrotuberous ligament and local tenderness point of coccyx. The evaluation of clinical outcome was done by pain intensity numerical rating scale (PI-NRS), pressure pain threshold (PPT) and EuroQol five dimensions questionnaire (EQ-5D) index. After treatment, their PI-NRS was decreased, PPT and EQ-5D index were increased. The pharmacoacupuncture therapy at entrapment point of perforating cutaneous nerve could be an effective way to treat coccygodynia caused by perforating cutaneous nerve entrapment syndrome.