• Title/Summary/Keyword: shaping methods

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Video Quality Representation Classification of Encrypted HTTP Adaptive Video Streaming

  • Dubin, Ran;Hadar, Ofer;Dvir, Amit;Pele, Ofir
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.8
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    • pp.3804-3819
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    • 2018
  • The increasing popularity of HTTP adaptive video streaming services has dramatically increased bandwidth requirements on operator networks, which attempt to shape their traffic through Deep Packet inspection (DPI). However, Google and certain content providers have started to encrypt their video services. As a result, operators often encounter difficulties in shaping their encrypted video traffic via DPI. This highlights the need for new traffic classification methods for encrypted HTTP adaptive video streaming to enable smart traffic shaping. These new methods will have to effectively estimate the quality representation layer and playout buffer. We present a new machine learning method and show for the first time that video quality representation classification for (YouTube) encrypted HTTP adaptive streaming is possible. The crawler codes and the datasets are provided in [43,44,51]. An extensive empirical evaluation shows that our method is able to independently classify every video segment into one of the quality representation layers with 97% accuracy if the browser is Safari with a Flash Player and 77% accuracy if the browser is Chrome, Explorer, Firefox or Safari with an HTML5 player.

Image reconstruction in electrical capacitance tomography based on modified generalized Landweber method (수정된 generalized Landweber 방법을 이용한 ECT 영상 복원)

  • Lee Seong-Hun;Jang Jae-Duck;Kim Yong-Sung;Kim Kyung-Youn;Choi Bong-Yeol
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.43 no.5 s.311
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    • pp.68-79
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    • 2006
  • Electrical capacitance tomography (ECT) is a non-invasive imaging reconstruction technique that aims at visualization of cross sectional permittivity distribution of dielectric object based on the measured capacitance. There are lots of iterative image reconstruction methods to accelerate convergence rate and enhance quality of reconstructed image, Among them iterative Landweber method is one of the widely used reconstruction algorithm in En. In this paper, modified generalized Landweber method is proposed to accelerate convergence rate. In doing so, acceleration term is considered to the generalized Landweber method with shaping matrix and an optimal step length is determined analytically. Extensive computer simulations are provided to illustrate the reconstruction performance of the proposed algorithm.

A Study on the Shaping Ability of Three Different Rotary Nickel-Titanium Instruments in Simulated Curved Root Canal (만곡 근관에서 다양한 엔진 구동형 Nickel-Titanium 파일의 근관 성형능력에 대한 연구)

  • Kim, Kyoung-A;Chon, Seong-Min;Kwon, Su-Mi;Lee, Kwang-Won;Yu, Mi-Kyung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.23 no.4
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    • pp.293-302
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    • 2007
  • I. Objectives The purpose of this study was to compare the shaping ability between the single length technique performed with Mtwo instruments (VDW, Munich, Germany) and the crown-down technique using K3 (SybronEndo, West Collins, CA, USA) and RaCe (FKG, La Chaux-de-Fonds, Switzerland) instruments. II. Materials & Methods Forty five curved canals in resin blocks were equally divided in to three groups. Group 1 (Mtwo) was instrumented used the full length of canal according to the manufacturer's instructions. The simulated canals was prepared to an instrument size of 35, 0.04 taper canal terminus. In group 2 (Race) and group 3 (K3) was instrumented in a crown-down manner and prepared to an instrument size of 30, 0.06 taper canal terminus. Pre- and post-instrumentation images were scanned and assessment of canal shape was completed with a computer image analysis program. Material removal was measured at 7 measuring points, beginning 1mm from the end point of preparation. Differenced of centering ratio were statistically analyzed using One-way ANOVA followed by Duncan's test. II. Results & Conclusion There was no significant difference on 1, 2, 3 and 7mm measuring point. At 4 and 5 measuring point, significant difference showed between the Mtow instruments and other two instruments. (p<0.05)

A Development of GUI Full-Energy Absorption Peak Analysis Program for Educational Purpose (전 에너지 흡수 피크 분석용 GUI 기반 교육용 프로그램 개발)

  • Sohn, Jong-Wan;Shin, Myung-Suk;Lee, Hye-Jung;Jung, Kyung-Su;Jeong, Min-Su;Kim, Sang-Nyeon
    • Journal of Radiation Protection and Research
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    • v.34 no.2
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    • pp.69-75
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    • 2009
  • To obtain precise information about characteristics of gamma ray detector system responses, we developed new GUI computer program to analize full-energy absorption peak using our developed Delphi computer code for educational purpose. By use of the well known 4 nonlinear peak shaping functions, peaks were fitted with least square fit method in this code. In this paper, we described the methods to search for 12 coefficients in above 4 nonlinear peak shaping functions by use of our developed code in details. The computer code was tested for 1 $\mu$Ci $^{137)Cs$ 661 keV gamma ray peak spectrum detected by 25 % relative efficiency HPGe detector with 5.35 cm (D) $\times$ 5.5 cm (L) size.

Micro-computed tomographic assessment of the shaping ability of the One Curve, One Shape, and ProTaper Next nickel-titanium rotary systems

  • Tufenkci, Pelin;Orhan, Kaan;Celikten, Berkan;Bilecenoglu, Burak;Gur, Gurkan;Sevimay, Semra
    • Restorative Dentistry and Endodontics
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    • v.45 no.3
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    • pp.30.1-30.11
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    • 2020
  • Objectives: This micro-computed tomographic (CT) study aimed to compare the shaping abilities of ProTaper Next (PTN), One Shape (OS), and One Curve (OC) files in 3-dimensionally (3D)-printed mandibular molars. Materials and Methods: In order to ensure standardization, 3D-printed mandibular molars with a consistent mesiobuccal canal curvature (45°) were used in the present study (n = 18). Specimens were instrumented with the OC, OS, or PTN files. The teeth were scanned pre- and post-instrumentation using micro-CT to detect changes of the canal volume and surface area, as well as to quantify transportation of the canals after instrumentation. Two-way analysis of variance was used for statistical comparisons. Results: No statistically significant differences were found between the OC and OS groups in the changes of the canal volume and surface area before and after instrumentation (p > 0.05). The OC files showed significantly less transportation than the OS or PTN systems for the apical section (p < 0.05). In a comparison of the systems, similar values were found at the coronal and middle levels, without any significant differences (p > 0.05). Conclusions: These 3 instrumentation systems showed similar shaping abilities, although the OC file achieved a lesser extent of transportation in the apical zone than the OS and PTN files. All 3 file systems were confirmed to be safe for use in mandibular mesial canals.

Calculation of thermal neutron scattering data of MgF2 and its effect on beam shaping assembly for BNCT

  • Jiaqi Hu;Zhaopeng Qiao;Lunhe Fan;Yongqiang Tang;Liangzhi Cao;Tiejun Zu;Qingming He;Zhifeng Li;Sheng Wang
    • Nuclear Engineering and Technology
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    • v.55 no.4
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    • pp.1280-1286
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    • 2023
  • MgF2 as a moderator material has been extensively used in the beam shaping assembly (BSA) that plays an important role in the boron neutron capture therapy (BNCT). Regarded as important for applications, the thermal neutron scattering data of MgF2 were calculated, based on the phonon expansion model. The structural properties of MgF2 were researched by the VASP code based on the ab-initio methods. The PHONOPY code was employed to calculate the phonon density of states. Furthermore, the NJOY code was used to calculate the thermal neutron scattering data of MgF2. The calculated inelastic cross sections plus absorption cross sections are in agreement with the available experimental data. The neutron transport in the BSA has been simulated by using a hybrid Monte-Carlo-Deterministic code NECP-MCX. The results indicated that compared with the calculation of the free gas model, the thermal neutron flux and epithermal neutron flux at the BSA exit port calculated by using the thermal neutron scattering data of MgF2 were reduced by 27.7% and 8.2%, respectively.

A Study of Facilitation Therapy (촉진치료에 관한 연구)

  • Bae, Sung-Soo;Han, Jin-Tae;Lee, Myung-Hee;Lee, Sang-Youl;Choi, Yong-Won
    • Journal of the Korean Society of Physical Medicine
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    • v.3 no.1
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    • pp.21-25
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    • 2008
  • Purpose : The objective of this study was conducted to find out the facilitation therapy. Therapeutic exercise concepts are changed from classical therapeutic exercise and neurophysiolosical approach to facilitation therapy. Methods : This is literature study with books and PNF international course books. Results : Facilitation concepts are changed. Complex movements are the result of spinal reflex-mechanism. It was changed the to reflex-reponses are variable and organization of complex movements are determined by the necessity to move. Therefore therapy goals and concepts of spasticity have to change. Conclusion : Facilitation therapy approach by use input systems, which are needed to interact with environmental and task demands. The systems are visual, tactile, propriocepsis, vestibular, acoustical and olfactory. Facilitation therapy need these system all together with shaping.

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Position and load-swing control of a 2-dimensional overhead crane (2차원 천정크레인의 위치 및 이송물의 흔들림제어)

  • Lee, Ho-Hoon;Cho, Sung-Kun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.10
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    • pp.1683-1693
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    • 1997
  • In this paper, a new nonlinear dynamic model is derived for a 2-dimensional overhead crane based on a new definition of 2-degree-of-freedom swing angle, and a new anti-swing control law is proposed for the crane. The dynamic model and control law take simultaneous travel and traverse motions of the crane into consideration. The model is first linearized for small motions of the crane load about the vertical stable equilibrium. Then the model becomes decoupled and symmetric with respect to the travel and traverse axes of the crane. From this result, a decoupled anti-swing control law is proposed based on the linearized model via the loop shaping and root locus methods. This decoupled method guarantees not only fast damping of load-swing but also zero steady state position error with optimal transient response for the 2-dimensional motion of the crane. Finally, the proposed control method is evaluated by controlling the simultaneous travel and traverse motions of a 2-dimensional prototype overhead crane. The effectiveness of the proposed control method is then proven by the experimental results.

Effects of Injection Conditions on the Mechanical Properties of Nd-Fe-B Dielectromagnets

  • B.Slusarek;D.Bialo;J.Gromek;T.Kulesza
    • Journal of Magnetics
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    • v.4 no.2
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    • pp.52-54
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    • 1999
  • Injection molding is one of the methods to prepare dielectromagnets-permanent magnets made from hard magnetic powder (or from mixture of powders) bonded by dielectric materials. Magnetic properties of dielectromagnets are worse than those of sintered magnets made from the same hard magnetic powders, but this type of the permanent magnet has many advantages. One of them is simpler technology-easier in comparison to the technology of sintered magnets. The injection molded dielectromagnets do not need any final treatment. This technology permits to control magnetic, thermal and mechanical properties of dielectromagnets. The main chracteristics of dielectormagnets are magnetic properties, however mechanical properties have serious influence onto a range of their applications. The main factors shaping mechanical properties have serious influence onto a range of their applications. The main factors shaping mechanical properties of dielectromagnets are the kind and quantity of resin and the technology. The purpose of this investigateion was to find the correlation between infection conditions and the mechanical properties of dielectromagnets. Influence of two parameters of injection, temperature and pressure on mechanical and magnetic properties of dielectromagnets were not significantly changed. Increasing of pressure of injection also does not influence on mechanical properties of analysed samples, however increasing of temperature of injection significantly improved both compression and bending strength.

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Comparison of the shaping ability of novel thermally treated reciprocating instruments

  • Keskin, Cangul;Demiral, Murat;Sariyilmaz, Evren
    • Restorative Dentistry and Endodontics
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    • v.43 no.2
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    • pp.15.1-15.7
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    • 2018
  • Objectives: The present study aimed to evaluate the shaping ability of 2 thermally treated nickel-titanium reciprocating systems in simulated curved canals. Materials and Methods: Forty simulated canals were prepared to apical size 25 using Reciproc Blue R25 (VDW) and WaveOne Gold Primary (Dentsply Sirona) instruments. Standard pre- and post-preparation images were taken and superimposed. The removal of resin material was measured at 5 standard points: the canal orifice, halfway between the canal orifice and the beginning of the curve, the beginning of the curve, the apex of the curve, and the end-point of the simulated canal. The data were analysed using the independent sample t-test with a 5% significance threshold. Results: The canals in which Reciproc Blue R25 was used showed a significantly greater widening than those in which WaveOne Gold was used at 4 of the 5 measurement points (p < 0.05). The Reciproc Blue R25 instrument removed significantly more resin from the inner aspect of the curve at 2 of the 5 points and similar amounts at the remaining 3 points. At the 2 apical points, there was no significant difference between the Reciproc Blue R25 and WaveOne Gold Primary instruments. Conclusion: Both instruments respected the original canal anatomy; however, WaveOne Gold resulted in a more conservative shape with less transportation.