• Title/Summary/Keyword: slices

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Induction of Oscillatory Firing Activity by TTX in Rat Cerebellar Purkinje Cells

  • Seo, Wha-Sook
    • The Korean Journal of Physiology
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    • v.29 no.1
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    • pp.103-111
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    • 1995
  • Intracellular recordings were obtained from Purkinje cells in rat cerebellar slices maintained in vitro. Adding tetrodotoxin to the superfusion solution produced a typical pattern of repetitive burst firing consisting of a cluster of action potentials followed by a long hyperpolarization. TTX-induced oscillatory activity was not due to modulation of membrane potential although underlying mechanisms for maintenance of oscillatory activity were influenced by membrane voltage. The mechanism of TTX-induced oscillation was not related to the presence or amplitude of $I_h$ and could still induce the oscillatory activity after blockade of $I_h$ by cesium. The result from an experiment in which QX-314 was injected intracellularly strongly suggested that TTX-induced oscillatory firing activity was due to blockade of post-synaptic $Na^{+}$ currents intrinsic to PCs.

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A Study on the Program Slicing Model (Program Slice 생성 모형에 관한 연구)

  • Yun Chang-Byeon;Cha Yeong-Heon;Jeong Chang-Mo
    • Journal of the military operations research society of Korea
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    • v.13 no.2
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    • pp.42-52
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    • 1987
  • Many programmers start debugging by reading the faulty program from start to bottom without investigating carefully the erroneous program. Expert programmers, however, trace backward from a particular variable in a specific statement to identify all possible sources of influence on the value of variable (program slice). Weiser proposed a slicing algorithm (method) that is complex, iterative and still in modification [3,4]. This paper presents a method to generate a program slice by use of matrix computation which represents all possible slices of the program. The matrix representation of a program is soundly based on the graph theory of data dependency.

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Sensitivity-based reliability analysis of earth slopes using finite element method

  • Ji, Jian;Liao, Hong-Jian
    • Geomechanics and Engineering
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    • v.6 no.6
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    • pp.545-560
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    • 2014
  • For slope stability analysis, an alternative to the classical limit equilibrium method (LEM) of slices is the shear strength reduction method (SRM), which can be integrated into finite element analysis or finite difference analysis. Recently, probabilistic analysis of earth slopes has been very attractive because it is capable to take the soil uncertainty into account. However, the SRM is less commonly extended to probabilistic framework compared to a variety of probabilistic LEM analysis of earth slopes. To overcome some limitations that hinder the development of probabilistic SRM stability analysis, a new procedure based on recursive algorithm FORM with sensitivity analysis in the space of original variables is proposed. It can be used to deal with correlated non-normal variables subjected to implicit limit state surface. Using the proposed approach, a probabilistic finite element analysis of the stability of an existing earth dam is carried out in this paper.

A Study on the Efficient Utilization of Farm Tractor and Power Tiller on the Inclined Upland (야산개발농지의 기계화 작업효율 증진에 관한 연구)

  • 최규홍
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.15 no.1
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    • pp.2925-2933
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    • 1973
  • For the efficient utilization of farm machines on the inclined uqland, work performance in plowing, harrowing and terracing and critical workable gradients were tested on three farm machines which are 47 ps-farm tractor, 8 ps-power tiller and 5 ps-power tiller. The results of this study are summarized as follows; 1) The steeper the slope of the upland was the more inefficient the work performance of all machines was. 2) The critical workable gradients of the machines were proved as 14 for 47 ps-farm tractor, 12 for 8 ps-power tiller and 10 for 5ps-power tiller. 3) Plowing in the way of turning the furrow slices against the slope in order to build up terraces, the critical workable gradients were 8 for 47 ps-farm tractor and 8 ps-power tiller and 6 for 5 ps-power tiller. 4) Two-way plow is recommended for plowing with farm tractor on inclined upland, and high lug of tire would be good to prevent the slippage, and side valance-weight should be attached to power tiller for preventing its overturning.

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Ultrasonic Sensors for Steel Structure Inspection (강구조물(鋼構造物) 진단(診斷)을 위한 초음파(超音波) 센서)

  • Shin, Byoung-Churl
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.2 no.2
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    • pp.170-176
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    • 1998
  • The team mixed PbO, $ZrO_2$, $TiO_2$, $Nb_2O_5$ and $MnCO_3$, to make $Pb[(Zr_{0.54}\;Ti_{0.46})\;Nb_{0.005}]O_3+4%MnCO_3$. The electroded PZT ceramics were poled by 3 kV/mm at $110^{\circ}C$ for 600 s. We assembled the 0.4mm thick PZT slices into ultrasonic transducers. Central frequency of the probe is 5 MHz, which is proper to the thickness gauge for steel pipes and for flaw detector. The probe can detect a disk shape defect of 1mm diameter at 15cm deep in steel block. The new probe's Fresnel zone that the ultrasonic beam do not broaden is 13mm. Over the Fresnel zone, the ultrasonic beam spreads. Half of the beam spread angle of the probe is $4.3^{\circ}-4.6^{\circ}$. This probe can be used for the ultrasonic transducers for non-destructive testing of steel bridges.

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Computed Tomographic Images of Vertebral Disc Herniation in Dogs (개에서 컴퓨터 단층 촬영 검사를 통한 추간판 탈출증 진단례)

  • 이기창;송경진;권정국;최민철
    • Journal of Veterinary Clinics
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    • v.20 no.4
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    • pp.519-522
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    • 2003
  • An appearance of herniated intervertebral disc into thoracolumbar vertebral canal was evaluated in two patients using computed tomography (CT). Before CT scanning, plain radiography and myelography were performed in both cases. CT images were compared to those of myelography. Dogs were positioned in sternal recumbency under inhalation anesthesia and transverse slices with 2 mm thickness were obtained around thoracolumbar region. The transverse CT images were examined using both vertebral and spiral window mode. The most common findings on CT images were loss of vertebral canal epidural fat, bulging of vertebral canal disc margins, displacement of spinal cord and flatted vertebral canal. Whereas, narrowed intervertebral disc space and simple extradural pattern were the main findings on plain and contrast radiographs. CT imges showed the extent of the herniated disc lesion, type II intervertebral disc hernation, and the displacement of spinal cord in detail in both occations. It is considered that degree and precise localization of the intervertebral disc herniation and subtle lesion of spinal cord could be identified accurately using computed tomography.

Effect of PAF Antagonists on the Alterations in Cerebral Hemodynamics in Transient Cerebral Ischemia (PAF 길항제가 일과성 뇌허혈에 의한 뇌혈류역학 변동에 미치는 효과)

  • 이원석;고수연
    • Biomolecules & Therapeutics
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    • v.7 no.3
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    • pp.234-241
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    • 1999
  • The present study assessed the cerebroprotective effect of platelet-activating factor(PAF) antagonists in transient cerebral ischemia of rats. Right middle cerebral artery (MCA) of Sprague-Dawley rats was occluded for 2 hours using an intraluminal filament technique, and was reperfused for 6 hours following cerebral ischemia. The infarct area of seven coronal brain slices was measured morphometrically following stain ing in the 2% 2,3,5-triphenyltetrazolium chloride solution. The changes in regional cerebral blood flow (rCBF) and pial arteriolar diameter were measured by laser-Doppler flowmetry and by a videomicroscopy, respectively. The infarct size was significantly reduced by PAF antagonists, BN 52021 and CV-6209, which were administered i.p. 10 min before MCA occlusion. Pretreatment with PAF antagonists significantly restored the changes in pial arterial diameter as well as those in rCBF during the period of cerebral ischemia-reperfusion. PAF antagonists significantly inhibited the inducible nitric oxide synthase activity in the pial arteries ipsilateral to ischemia. These results suggest that PAF antagonists exert a cerebroprotective effect against ischemic brain damage through an improvement of postocclusive cerebral blood flow.

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Low area field-programmable gate array implementation of PRESENT image encryption with key rotation and substitution

  • Parikibandla, Srikanth;Alluri, Sreenivas
    • ETRI Journal
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    • v.43 no.6
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    • pp.1113-1129
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    • 2021
  • Lightweight ciphers are increasingly employed in cryptography because of the high demand for secure data transmission in wireless sensor network, embedded devices, and Internet of Things. The PRESENT algorithm as an ultralightweight block cipher provides better solution for secure hardware cryptography with low power consumption and minimum resource. This study generates the key using key rotation and substitution method, which contains key rotation, key switching, and binary-coded decimal-based key generation used in image encryption. The key rotation and substitution-based PRESENT architecture is proposed to increase security level for data stream and randomness in cipher through providing high resistance to attacks. Lookup table is used to design the key scheduling module, thus reducing the area of architecture. Field-programmable gate array (FPGA) performances are evaluated for the proposed and conventional methods. In Virtex 6 device, the proposed key rotation and substitution PRESENT architecture occupied 72 lookup tables, 65 flip flops, and 35 slices which are comparably less to the existing architecture.

Simulating the Lyman-Alpha Forest with Massive Neutrinos and Dark Radiation for Large-Volume Surveys

  • Rossi, Graziano
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.57.1-57.1
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    • 2019
  • In support of current and upcoming large-volume cosmological surveys such as the SDSS-IV eBOSS, LSST, and DESI, we present an extensive suite of high-resolution cosmological hydrodynamical simulations spanning a large range of cosmological and astrophysical parameters. We follow the evolution of gas, dark matter, neutrinos, and dark radiation, and consider several combinations of box sizes and number of particles - enhancing the resolution up to $3{\times}33283=110$ billion particles in a (100 h-1 Mpc)3 box size. We also provide 100,000 skewers for a variety of redshift slices and combination of cosmological and astrophysical parameters, useful for interpreting upcoming high-quality $Lyman-{\alpha}$ forest data. These novel simulations represent an improvement over our previous runs, and can be useful for a broader variety of cosmological and astrophysical applications, ranging from the three-dimensional modeling of the $Lyman-{\alpha}$ forest to cross-correlations between different probes, for studying the expansion history of the Universe including massive neutrinos, and for particle-physics related topics.

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PROJECTIONS AND SLICES OF MEASURES

  • Selmi, Bilel;Svetova, Nina
    • Communications of the Korean Mathematical Society
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    • v.36 no.2
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    • pp.327-342
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    • 2021
  • We consider a generalization of the Lq-spectrum with respect to two Borel probability measures on ℝn having the same compact support, and also study their behavior under orthogonal projections of measures onto an m-dimensional subspace. In particular, we try to improve the main result of Bahroun and Bhouri [4]. In addition, we are interested in studying the behavior of the generalized lower and upper Lq-spectrum with respect to two measures on "sliced" measures in an (n - m)-dimensional linear subspace. The results in this article establish relations with the Lq-spectrum with respect to two Borel probability measures and its projections and generalize some well-known results.