• Title/Summary/Keyword: Small-size window

Search Result 104, Processing Time 0.025 seconds

Assessment of Water Quality Calibration Criteria for Field-Scale Water Quality Model

  • Seong, Choung-Hyun;Kim, Sang-Min;Park, Seung-Woo;Park, Tae-Yang;Kim, Sung-Jae;Jung, Ki-Woong
    • Journal of agriculture & life science
    • /
    • v.44 no.5
    • /
    • pp.101-107
    • /
    • 2010
  • The objective of this study was to assess the statistics and associated criteria for field-scale model used to simulate nutrient concentrations in paddy field. CREAMS-PADDY, a modified version of the field-scale CREAMS model, simulates the hydrologic, sediment, and nutrient cycles in paddy fields was applied in this study. The model was calibrated and validated using data from study rice paddy fields in Republic of Korea. The calibration statistics include mean and the minimum-maximum range associated with a "temporal window" that spans a period of several days. Because nutrient concentrations in paddy filed are typically sampled infrequently (on a weekly basis, at best) and represent only an instant in time, it is not reasonable to expect any model to simulate a daily average concentration equal to an observed value on a particular day. The 5-day window and related calibration statistics were applied in this study and the applicability of this concept was tested for field-scale water quality model. As a result of calibration and validation, the ponded water nutrient concentration values showed only small changes except the fertilization period. Because of the small changes in ponded water concentration, the size of 5-day window was too small to capture the observed values. Further study is required to establish the 5-day window calibration method for field-scale water quality modeling.

SENSITIVITY ANALYSIS ABOUT THE METHODS OF UTILIZING THE HIGH RESOLUTION CLIMATE MODEL SIMULATION FOR KOREAN WATER RESOURCES PLANNING (II) : NUMERICAL EXPERIMENTS

  • Jeong, Chang-Sam;Hwang, Man-Ha;Ko, Ick-Hwan;Heo, Jun-Haeng;Bae, Deg-Hyo
    • Water Engineering Research
    • /
    • v.6 no.2
    • /
    • pp.73-89
    • /
    • 2005
  • Two kinds of high resolution GCMs with the same spatial resolutions but with different schemes run by domestic and foreign agencies are used to clarify the usefulness and sensitivity of GCM for water resources applications for Korea. One is AMIP-II (Atmospheric Model Intercomparison Project-II) type GCM simulation results done by ECMWF (European Centre for Medium-Range Weather Forecasts) and the other one is AMIP-I type GCM simulation results done by METRI (Korean Meteorological Research Institute). Observed mean areal precipitation, temperature, and discharge values on 7 major river basins were used for target variables. Monte Carlo simulation was used to establish the significance of the estimator values. Sensitivity analyses were done in accordance with the proposed ways. Through the various tests, discrimination condition is sensitive for the distribution of the data. Window size is sensitive for the data variation and the area of the basins. Discrimination abilities of each nodal value affects on the correct association. In addition to theses sensitivity analyses results, we also noticed some characteristics of each GCM. For Korean water resources, monthly and small window setting analyses are recommended using GCMs.

  • PDF

Impulse Noise Filtering through Evolutionary Approach using Noise-free Pixels (무잡음 화소를 이용한 진화적인 방법의 임펄스 잡음 필터링)

  • Mahmood, Muhammad Tariq;Choi, Young Kyu
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.2 no.5
    • /
    • pp.347-352
    • /
    • 2013
  • In impulse noise filtering techniques window size play an important role. Usually, an appropriate window is determined according to the noise density. A small window may not be able to suppress noise properly whereas a large window may remove edges and fine image details. Moreover, the value of the central pixel is estimated by considering all pixels within the window. In this work, contrary to the previous approaches, we propose an iterative impulse noise removal scheme that emphasizes on noise-free pixels within a small neighborhood. The iterative process continues until all noisy pixels are replaced with the estimated pixels. In order to estimate the optimal value for a noisy pixel, a genetic programming (GP) based estimator is evolved that takes few noise-free pixels as input. The estimator is constituent of noise-free pixels, arithmetic operators and random constants. Experimental results show that theproposed scheme is capable of removing impulse noise effectively while preserving the fine image details. Especially, our approach has shown effectiveness against high impulse noise density.

Construction of Structured q-ary LDPC Codes over Small Fields Using Sliding-Window Method

  • Chen, Haiqiang;Liu, Yunyi;Qin, Tuanfa;Yao, Haitao;Tang, Qiuling
    • Journal of Communications and Networks
    • /
    • v.16 no.5
    • /
    • pp.479-484
    • /
    • 2014
  • In this paper, we consider the construction of cyclic and quasi-cyclic structured q-ary low-density parity-check (LDPC) codes over a designated small field. The construction is performed with a pre-defined sliding-window, which actually executes the regular mapping from original field to the targeted field under certain parameters. Compared to the original codes, the new constructed codes can provide better flexibility in choice of code rate, code length and size of field. The constructed codes over small fields with code length from tenths to hundreds perform well with q-ary sum-product decoding algorithm (QSPA) over the additive white Gaussian noise channel and are comparable to the improved spherepacking bound. These codes may found applications in wireless sensor networks (WSN), where the delay and energy are extremely constrained.

Improving Performance of YOLO Network Using Multi-layer Overlapped Windows for Detecting Correct Position of Small Dense Objects

  • Yu, Jae-Hyoung;Han, Youngjoon;Hahn, Hernsoo
    • Journal of the Korea Society of Computer and Information
    • /
    • v.24 no.3
    • /
    • pp.19-27
    • /
    • 2019
  • This paper proposes a new method using multi-layer overlapped windows to improve the performance of YOLO network which is vulnerable to detect small dense objects. In particular, the proposed method uses the YOLO Network based on the multi-layer overlapped windows to track small dense vehicles that approach from long distances. The method improves the detection performance for location and size of small vehicles. It allows crossing area of two multi-layer overlapped windows to track moving vehicles from a long distance to a short distance. And the YOLO network is optimized so that GPU computation time due to multi-layer overlapped windows should be reduced. The superiority of the proposed algorithm has been proved through various experiments using captured images from road surveillance cameras.

Analysis of airborne sound insulation performance by the experiment using small size specimen (축소시편 실험을 통한 공기전달음 차단성능 분석)

  • Kim, Hang;Park, Hyeon Ku;Goo, Hee Mo;Kim, Sun-Woo
    • KIEAE Journal
    • /
    • v.14 no.1
    • /
    • pp.83-89
    • /
    • 2014
  • The residents' demand for the comfortable life is promoting development of wall and window which has high sound insulation performance. To develop wall system, various aspects should be considered on the environment, material, construction and structure. Especially focusing on the acoustical view, the economical solution is one of the most critical point. Recently the interest on the partition wall is being increased, because it is useful for the Rahmen type apartment which is considered as an alternative to reduce floor impact sound. This study examines simplified measurement method of airborne sound insulation applied small size specimen, in order to save money to be used for the standard specimen then to promote the development process. The results showed that the simplified method could be effective for the wall system the sound insulation performance upto Rw 50 dB, and for the judgement of rank order of sound insulation performance of the similar wall type while developing.

Laser Speckle Imaging Using Adaptive Windowing Method (적응 윈도우 기법을 사용한 레이저 스펙클 영상의 처리)

  • Jin, Ho-Young;Shin, Hyun-Chool
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.47 no.1
    • /
    • pp.97-102
    • /
    • 2010
  • A laser speckle is a random pattern that has a granular appearance produced by reflected light when a coherent laser illuminates an irregular course surface. Most important property of laser speckle is detecting micro-vascular. Speckle image needs image processing to detect micro-vascular. This paper proposes a new image processing method for laser speckle, adaptive window method that adaptively processes laser speckle images in the spatial. Conventional fixed window based LASCA has shortcoming in that it uses the same window size regardless of target areas. Inherently laser speckle contains undesired noise. Thus a large window is helpful for removing the noise but it results in low resolution of image. Otherwise a small window may detect micro vascular but it has limits in noise removal. To overcome this trade-off, we newly introduce the concept of adaptive window method to conventional laser speckle image analysis. We have compared conventional LASCA and its variants with the proposed method in terms of image quality and processing complexity.

A study on the stereo matching using diffusion networks (확산망을 이용한 스테레오 정합에 관한 연구)

  • 이상찬;남기곤;김재창;강창순;정두영;이상욱
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.35S no.2
    • /
    • pp.126-136
    • /
    • 1998
  • One of the central problems in sereo matching is the selectionof the optimal window sizes for comparing image regions. The window size must be large enough to include enough variation for reliable matching, but small enough to avoid the effect of projection distortion. This paper discusses these problems with some novel algorithm based on iterativediffusion process at different disparity hypotheses. Also this paper proposes four kinds of diffusion algorithms to preseve discontinuity in stereo matching. We present and discuss extensive empirical results of algorithms based on various sets of synthetic and real image.

  • PDF

A detection scheme of input estimation filter

  • Lee, Hungu;Tahk, Minjea
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1995.10a
    • /
    • pp.496-499
    • /
    • 1995
  • In this paper, a new detection scheme, the detectable maneuver set (DMS) scheme, is proposed by incorporating the trade-off property between target maneuver magnitude and detection time delay. With this new detection scheme, small maneuvers can be effectively detected without enlarging window size. Simulation results show that the proposed DMS scheme gives better tracking performance.

  • PDF

A Case Study on the Interior Design Remodeling of Apartment according to the Floors Space in Seoul (서울지역 아파트의 규모별 실내디자인 리모델링에 대한 심층 사례 연구)

  • Shin Kyung-Joo;Rhee Ji-Young;Jang Sang-Ock
    • Journal of the Korean housing association
    • /
    • v.16 no.2
    • /
    • pp.1-10
    • /
    • 2005
  • The purpose of this study is providing useful information for consumer-friendly house plan by investigating remodeling apartments according to the area type and size. In order to achieve this aim, case study was applied. The case study was conducted of five small, medium, and large size apartments through depth-interviews, actual survey, and questionnaires on the remodeling behavior, interior design, and interior atmosphere. The results of the study are as follows: Structural alterations were frequent in communal area, and then in private and household areas. Changing lighting fixtures was frequent in all area types, and especially, in communal areas installing extra decoration was frequently observed. Besides, alterations of doors and window frames were carried out in communal, private, housework and service areas by using wood, aluminum sashes, double-glazing, and paint coating. Finally, in housework areas the material and color of counters were changed into wooden and achromatic.