• Title/Summary/Keyword: various processing methods

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Internet Protocols Over ABR and UBR Services: Problems, Approaches, and Their Evaluation (ABR과 UBR 서비스 상에서 인터넷 프로토콜: 문제점, 해결방안, 그리고 성능평가)

  • Park, Seung-Seop;Yuk, Dong-Cheol
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.11S
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    • pp.3260-3268
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    • 1999
  • As the proliferation of multimedia traffic over High-speed Internet increases, ATM network will be vital to adopt as backbone network over various parts of Internet. In this paper, we investigate the performance of TCP/IP traffic flow over ABR and UBR of ATM service to study for the high throughput and good fairness by simulation technique. Although TCP is run in the transport layer, it is controlled by several methods, e.g, EPD, PPD, RED, EFCI, ER etc, in ATM layer when TCP uses the ABR/UBR service. Therefore, if one cell is discarded in ATM layer, a packet of TCp will be laost. And, also, along with the increasing of the number of VC among switches, the throughput and fairness will be degraded. In order to improve these degradations, we propose the effective parameter control operations of EFCI and ER on ABR service, and also suggest the buffer management methods on UBR service. Finally, through the simulation results, the improved throughput and fairness are shown.

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Terrain Classification for Enhancing Mobility of Outdoor Mobile Robot (실외 주행 로봇의 이동 성능 개선을 위한 지형 분류)

  • Kim, Ja-Young;Lee, Jong-Hwa;Lee, Ji-Hong;Kweon, In-So
    • The Journal of Korea Robotics Society
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    • v.5 no.4
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    • pp.339-348
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    • 2010
  • One of the requirements for autonomous vehicles on off-road is to move stably in unstructured environments. Such capacity of autonomous vehicles is one of the most important abilities in consideration of mobility. So, many researchers use contact and/or non-contact methods to determine a terrain whether the vehicle can move on or not. In this paper we introduce an algorithm to classify terrains using visual information(one of the non-contacting methods). As a pre-processing, a contrast enhancement technique is introduced to improve classification of terrain. Also, for conducting classification algorithm, training images are grouped according to materials of the surface, and then Bayesian classification are applied to new images to determine membership to each group. In addition to the classification, we can build Traversability map specified by friction coefficients on which autonomous vehicles can decide to go or not. Experiments are made with Load-Cell to determine real friction coefficients of various terrains.

A Weight Map Based on the Local Brightness Method for Adaptive Unsharp Masking (적응형 언샤프 마스킹을 위한 지역적 밝기 기반의 가중치 맵 생성 기법)

  • Hwang, Tae Hun;Kim, Jin Heon
    • Journal of Korea Multimedia Society
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    • v.21 no.8
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    • pp.821-828
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    • 2018
  • Image Enhancement is used in various applications. Among them, unsharp masking methods can improve the contrast with a simple operation. However, it has problems of noise enhancement and halo effect caused by the use of a single filter. To solve this problems, adaptive processing using multi-scale and bilinear filters is being studied. These methods are effective for improving the halo effect, but it require a lot of calculation time. In this paper, we want to simplify adaptive filtering by generating a weight map based on local brightness. This weight map enables adaptive processing that eliminates the halo effect through a single multiplication operation. Through experiments, we confirmed the suppression of the halo effect through the result image of the proposed algorithm and existing algorithm.

A Survey of Face Recognition Techniques

  • Jafri, Rabia;Arabnia, Hamid R.
    • Journal of Information Processing Systems
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    • v.5 no.2
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    • pp.41-68
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    • 2009
  • Face recognition presents a challenging problem in the field of image analysis and computer vision, and as such has received a great deal of attention over the last few years because of its many applications in various domains. Face recognition techniques can be broadly divided into three categories based on the face data acquisition methodology: methods that operate on intensity images; those that deal with video sequences; and those that require other sensory data such as 3D information or infra-red imagery. In this paper, an overview of some of the well-known methods in each of these categories is provided and some of the benefits and drawbacks of the schemes mentioned therein are examined. Furthermore, a discussion outlining the incentive for using face recognition, the applications of this technology, and some of the difficulties plaguing current systems with regard to this task has also been provided. This paper also mentions some of the most recent algorithms developed for this purpose and attempts to give an idea of the state of the art of face recognition technology.

Evaluation of Fabric Pilling Using Hybrid Imaging Methods

  • Kim Sung-Min;Park Chang-Kyu
    • Fibers and Polymers
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    • v.7 no.1
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    • pp.57-61
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    • 2006
  • A study has been made on the quantification and evaluation of fabric pilling using two-dimensional and three-dimensional hybrid imaging methods. Two-dimensional imaging method was good for some samples while three-dimensional measurement method for others, according to the properties of their base fabric. Various image processing techniques as well as three-dimensional data processing algorithms were applied for the extraction of pills from measured data and a series of shape parameters have been defined for the objective evaluation of fabric pilling. An evaluation criterion that is compatible with the conventional evaluation method has been proposed by applying the new evaluation method to the current photographic standards.

Effects of Various Processing Methods on the Contents of Alkaloids in the Cho O(Aconiti Ciliare Tuber) (초오의 수치방법에 따른 알칼로이드 함량)

  • Lee, Hye-Won;Jeon, Won-Kyung;Kim, Ho-Kyoung
    • Korean Journal of Pharmacognosy
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    • v.33 no.4 s.131
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    • pp.296-300
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    • 2002
  • The contents of alkaloids in raw Cho O(Aconiti Ciliare Tuber) and its processed products were determined by high performance liquid chromatography. Processing methods 1 and 2 lowered the contents of alkaloids more than the method 3. Cho O processed with method 1 or 2 showed even lower alkaloid contents than commercially available Processed Aconiti Tuber Powder(PATP). The contents of aconitine and hypaconitine in MeOH extracts of Cho O treated with method 3(10 min irradiation) and mesaconitine of Cho O treated with method 3(5 min) were comparable to those of PATP.

Image Quality Enhancement Method using Retinex in HSV Color Space and Saturation Correction (HSV 컬러 공간에서의 레티넥스와 채도 보정을 이용한 화질 개선 기법)

  • Kang, Han-Sol;Ko, Yun-Ho
    • Journal of Korea Multimedia Society
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    • v.20 no.9
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    • pp.1481-1490
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    • 2017
  • This paper presents an image quality enhancement algorithm for dark image acquired under poor lighting condition. Various retinex algorithms which are human perception-based image processing methods were proposed to solve this problem. Although MSR(Multi-Scale Retinex) among these algorithm works well under most lighting condition, it shows color degradation because their separate nonlinear processing of RGB color channels. To compensate for the loss of the color, MSRCR(Multi-Scale Retinex with Color Restoration) was proposed. However, it requires high computational load and has additional parameters that need to be adjusted according to input image. In order to overcome this problem, a new retinex algorithm based on MSR is proposed in this paper. The proposed method consists of V channel MSR, saturation correction, and separate contrast enhancement process. Experimental results show that the subjective and objective image quality of the proposed method better than those of the conventional methods.

A Brief review of Aragonite Precipitated Calcium Carbonate (PCC) Synthesis Methods and Its Applications

  • Ramakrishna, Chilakala;Thenepalli, Thriveni;Ahn, Ji Whan
    • Korean Chemical Engineering Research
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    • v.55 no.4
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    • pp.443-455
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    • 2017
  • This article provides an exclusive overview of the synthesized aragonite precipitated calcium carbonate and its applications in various fields. The last decade has seen a steady increase in the number of publications describing the synthesis, characterization and applications of calcium carbonate morphologies. Mainly, two kinds of processes have been developed for the synthesis of aragonite precipitated calcium carbonate under controlled temperature, concentrations and aging, and the final product is single-phase needle-like aragonite precipitated calcium carbonate formed. This review is mainly focused on the history of developed methods for synthesizing aragonite PCC, crystal growth mechanisms and carbonation kinetics. Carbonation is an economic, simple and ecofriendly process. Aragonite PCC is a new kind of functional filler in the paper and plastic industries, nowadays; aragonite PCC synthesis is the most exciting and important industrial application due to numerous attractive properties. This paper describes the aragonite PCC synthetic approaches and discusses some properties and applications.

Analytical Study on the Cooking in "Bok Sik Bang" (복식방의 조리에 관한 분석적 연구)

  • 이혜정;이성우
    • The Korean Journal of Food And Nutrition
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    • v.3 no.2
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    • pp.185-200
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    • 1990
  • "Bok Sik Bang', a book of cooking, was written in Korea in the 17 th century Various Cooking methods Of traditional foods were described in this book. 1. The kinds of cooking foods were Wine(59), Side dish(39), Seasoning(12), and Dessert(5) 2. The materials used in the cooking foods were cereals, vegetables, fishes, meats and etc. 3. The cooking methods were different and complicated. 4. The way of heating were also different such as to stew, to boil, to pan-boil, to frying, etc. 5. Utensils and table wares used for processing and cooking were poor and specific. 6. The measuring units were not accurate and unscientific. 7. Many of special words and expressions which are not used today in cooking and processing were reviewed.ewed.

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Effect of Preparation on Structure and Magnetic Properties of ZnFe2O4

  • Niyaifar, Mohammad
    • Journal of Magnetics
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    • v.19 no.2
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    • pp.101-105
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    • 2014
  • In this work, Zinc ferrite nanoparticles have been prepared by various methods, conventional (ZC), mechanochemical processing (ZM) and Sol-Gel (ZS) method, to compare their structural and magnetic properties. The cation distribution obtained from XRD shows the degrees of inversions are 4%, 14.8%, and 16.4% from the normal $ZnFe_2O_4$ structure. Fourier transform infrared spectroscopy (FT-IR) confirms changes in cation distribution of $ZnFe_2O_4$ fabricated by sol-gel and mechanochemical processing. The $^{57}Fe$ M$\ddot{o}$ssbauer spectra of the samples were recorded at room temperature. The spectra exhibit a line broadening. The magnetic properties of the samples were studied by vibration sample magnetometer (VSM) at room temperature and the results show that the sample ZM has ferrimagnetic behaviour.