• Title/Summary/Keyword: slice

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Seizure and Epilepsy Models on Hippocampal Slices of Rats (흰쥐 해마절편에서의 간질발작 및 간질모델)

  • Kwon, Oh-Young
    • Annals of Clinical Neurophysiology
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    • v.1 no.2
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    • pp.147-153
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    • 1999
  • Hippocampal slice models can be a powerful tool to study the mechanism of partial epilepsy. Despite the loss of connection with the rest of the brain, in vitro hippocampal slice preparations allow detailed physiological and pharmacological studies, which would be impossible, in vivo. There are several methods to induce electrographic seizures on hippocampal slice models. Those are electrical pulse train stimulation, 0 $Mg^{2+}$ artificial cerebrational fluid and high concentration of extracelluar $K^+$ on bath. Among them, the electrically triggered seizure may mimic the physiological communication between neuronal populations without any deterioration of normal physiologic and chemical status of the hippocampal slice models. Presumably, such communication from hyperexcitable areas to other neuronal populations is involved in the development of epilepsy. Electrographic seizures in hippocampal slice models occur in the network of neurons that are involved in epileptic seizures in the hippocampus in vivo. Because these models have many advantages and are very valuable to research of epileptogenesis on partial epilepsy, I would like to introduce the electrophysiological methods to induce electrographic seizure or epilepsy on hippocampal slice models briefly in this paper.

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Performance Comparison of the CCA Adaptive Equalization Algorithm based on Compact Slice Weighting Values in 16-QAM Signal (16-QAM 신호에서 Compact Slice 가중치에 의한 CCA 적응 등화 알고리즘의 성능 비교)

  • Kang, Dae-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.4
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    • pp.127-133
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    • 2013
  • This paper compare the performance of CCA (Compact Constellation Algorithm) adaptive equalization algorithm by effect of the compact slice weighting value for minimization of the intersymbol interference in the communication channel. The CCA combines the conventional DDA and RCA algorithm, it uses the constant modulus of the transmission signal and the considering the output of decision device by the power of compact slice weighting value in order to improving the initial convergence characteristics and the equalization noise by misadjustment in the steady state. In this process, it is confirmed by computer simulation that the compact slice weight affects the performance of CCA adaptive equalization algorithm. The performance index includes the output signal constellation, the residual isi and maximum distortion and MSE that is for the convergence characteristics, the SER according to the signal and noise power ratio at the channel is used. As a result of computer, it shows that the large weighting value gives more good in every performance index. But in SER performance, it is known that the small values gives more good in low SNR and the large values gives more good in high SNR.

Development of a Moldboard Plow to Invert Furrow Slice at the Same Position (토양의 제자리 반전을 위한 몰드보드 플라우의 개발)

  • 이규승;박원엽;권병기
    • Journal of Biosystems Engineering
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    • v.29 no.1
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    • pp.9-20
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    • 2004
  • On the basis of design theory of soil inversion, two types of moldboard plow with secondary soil mover was designed and constructed to invert furrow slice at same position with furrow bottom. A series of soil bin experiment was carried to investigate the performance of prototypes. First prototype of new concept plow showed two kinds of problems during the preliminary experiment. For the plowing depth of 6cut the prototype did not invert the furrow slice, instead it just cut furrow bottom and the furrow slice returned to the original position. For the plowing depth of 8cm, there was soil clogging problem at the rear part of plow. From the above results it was concluded that the first prototype can not be used for the inversion of furrow slice at same position with furrow bottom. Second prototype could invert furrow slice at the same position with furrow bottom, but the performance was affected by soil moisture content soil hardness and plowing speed very much. For the higher soil moisture content, for the higher soil hardness and higher plowing speed, the prototype showed higher soil inversion performance. For the second prototype the inversion ratio was almost 100%, inversion angle was in the range of 90 to 100 degree and side displacement was less than 4 cm. But the furrow slice was not continuous, it was cut in the length of 30 to 40 cm. The reason why the furrow slice was cut in that length is blamed for the design of moldboard surface. The specific draft of prototype was in the range of 37.24 kN/㎡ to 42.14 kN/㎡ this value is a little higher than that of the conventional plow, or from 30.38 kN/㎡ to 33.32 kN/㎡. But the difference was not so big. The inversion performance of the second prototype for the field experiment was much better than that of soil bin experiment due to the better soil and operational conditions. Sticky and compacted soil conditions, and higher plowing speed was suitable for the plowing operation of the second prototype

The Prediction of 'Slice' Using Neural Network in Golf Swing (골프스윙시 인공지능 을 이용한 (Neural Network) 슬라이스 예측에 관한 연구)

  • 심태용;오승일;신성휴;이상식;문정환
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1221-1224
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    • 2004
  • In this study, we developed a method classifying slice shot during golf practice using backpropagation algorithm. The 144 data based on the backpropagation model(11 inputs, 2 outputs) was used as a learning set and the model was verified based on the extra 50 data in the process to predict a slice shot in golf swing. The results showed 100% separating rate of learning set and 91.5% separating rate of verified set. The developed method can be potentially beneficial for the predicting of slice shot in an indoor golf excercise setting without applying any additional equipment.

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Study on Slice Sensitivity Profile and Reconstruction Resolution on Helical CT System (Helical CT 시스템에 있어 Slice Sensitivity Profile과 Reconstruction Resolution에 관한 연구)

  • Yoon, Han-Sik
    • Journal of radiological science and technology
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    • v.20 no.1
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    • pp.15-20
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    • 1997
  • Unlike conventional CT scan, the helical CT scan uses continuous rotating CT equipment with a slip ring to move the patient's coach at a constant speed while continuously scanning. Slice sensitivity profiles in the Z-position(SSPz) using the conventional X-ray CT have a shape similiar to a rectangular wave, which slightly spreads out into plains below the mountain. However, in the helical CT, with an expansion of the base, the rectangular shape collapses and a mouatain-like shape can be seen. We need to investigate the fellowing factors in helical CT scanning;the ability to scan along the axis of the body, effective slice width, slice shape and the precision of coach velocity, Helical scanning with sprial X-ray track is different from the conventional scanning in terms of the principle of image reconstruction performed. We believe that the problems in helical scanning can be solved by understanding new the special parameters such as the bed moving speed and the interval of image reconstruction.

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Efficient Slice Allocation Method using Cluster Technology in Fifth-Generation Core Networks

  • Park, Sang-Myeon;Mun, Young-Song
    • Journal of information and communication convergence engineering
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    • v.17 no.3
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    • pp.185-190
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    • 2019
  • The explosive growth of data traffic and services has created cost challenges for networks. Studies have attempted to effectively apply network slicing in fifth generation networks to provide high speed, low latency, and various compatible services. However, in network slicing using mixed-integer linear programming, the operation count increases exponentially with the number of physical servers and virtual network functions (VNFs) to be allocated. Therefore, we propose an efficient slice allocation method based on cluster technology, comprising the following three steps: i) clustering physical servers; ii) selecting an appropriate cluster to allocate a VNF; iii) selecting an appropriate physical server for VNF allocation. Solver runtimes of the existing and proposed methods are compared, under similar settings, with respect to intra-slice isolation. The results show that solver runtime decreases, by approximately 30% on average, with an increase in the number of physical servers within the cluster in the presence of intra-slice isolation.

Influence of slice thickness of computed tomography and type of rapid protyping on the accuracy of 3-dimensional medical model (CT절편두께와 RP방식이 3차원 의학모델 정확도에 미치는 영향에 대한 연구)

  • Um Ki-Doo;Lee Byung-Do
    • Imaging Science in Dentistry
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    • v.34 no.1
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    • pp.13-18
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    • 2004
  • Purpose : This study was to evaluate the influence of slice thickness of computed tomography (CT) and rapid protyping (RP) type on the accuracy of 3-dimensional medical model. Materials and Methods: Transaxial CT data of human dry skull were taken from multi-detector spiral CT. Slice thickness were 1, 2, 3 and 4 mm respectively. Three-dimensional image model reconstruction using 3-D visualization medical software (V-works /sup TM/ 3.0) and RP model fabrications were followed. 2-RP models were 3D printing (Z402, Z Corp., Burlington, USA) and Stereolithographic Apparatus model. Linear measurements of anatomical landmarks on dry skull, 3-D image model, and 2-RP models were done and compared according to slice thickness and RP model type. Results: There were relative error percentage in absolute value of 0.97, 1.98,3.83 between linear measurements of dry skull and image models of 1, 2, 3 mm slice thickness respectively. There was relative error percentage in absolute value of 0.79 between linear measurements of dry skull and SLA model. There was relative error difference in absolute value of 2.52 between linear measurements of dry skull and 3D printing model. Conclusion: These results indicated that 3-dimensional image model of thin slice thickness and stereolithographic RP model showed relative high accuracy.

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Recognition of Radar Emitter Signals Based on SVD and AF Main Ridge Slice

  • Guo, Qiang;Nan, Pulong;Zhang, Xiaoyu;Zhao, Yuning;Wan, Jian
    • Journal of Communications and Networks
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    • v.17 no.5
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    • pp.491-498
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    • 2015
  • Recognition of radar emitter signals is one of core elements in radar reconnaissance systems. A novel method based on singular value decomposition (SVD) and the main ridge slice of ambiguity function (AF) is presented for attaining a higher correct recognition rate of radar emitter signals in case of low signal-to-noise ratio. This method calculates the AF of the sorted signal and ascertains the main ridge slice envelope. To improve the recognition performance, SVD is employed to eliminate the influence of noise on the main ridge slice envelope. The rotation angle and symmetric Holder coefficients of the main ridge slice envelope are extracted as the elements of the feature vector. And kernel fuzzy c-means clustering is adopted to analyze the feature vector and classify different types of radar signals. Simulation results indicate that the feature vector extracted by the proposed method has satisfactory aggregation within class, separability between classes, and stability. Compared to existing methods, the proposed feature recognition method can achieve a higher correct recognition rate.

A Slice-based Complexity Measure (슬라이스 기반 복잡도 척도)

  • Moon, Yu-Mi;Choi, Wan-Kyoo;Lee, Sung-Joo
    • The KIPS Transactions:PartD
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    • v.8D no.3
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    • pp.257-264
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    • 2001
  • We developed a SIFG (Slice-based Information Graph), which modelled the information flow on program on the basis of the information flow of data tokens on data slices. Then we defied a SCM (Slice-based complexity measure), which measured the program complexity by measuring the complexity of information flow on SIFG. SCM satisfied the necessary properties for complexity measure proposed by Briand et al. SCM could measure not only the control and data flow on program but also the physical size of program unlike the existing measures.

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