• Title/Summary/Keyword: 가중거리

Search Result 202, Processing Time 0.024 seconds

Comparison of the Methodologies for Calculating Expressway Space Mean Speed Using Vehicular Trajectory Information from a Radar Detector (레이더검지기의 차량 궤적 정보를 이용한 고속도로 공간평균속도 산출방법 비교)

  • Han, Eum;Kim, Sang Beom;Rho, Jeong Hyun;Yun, Ilsoo
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.15 no.3
    • /
    • pp.34-44
    • /
    • 2016
  • This study was initiated to evaluate the performance of methodologies to estimate the space mean speed(SMS) using the time mean speed(TMS) which was collected from the vehicle detection system(VDS) in expressways. To this end, the methodologies presented in prior studies were firstly summarized. It is very hard to achieve exact SMSs and TMSs due to mechanical and communication errors in the field. Thus, a microscopic traffic simulation model was utilized to evaluated the performance. As a result, the harmonic mean and volume-distance weighted harmonic mean were close to the SMS in the case in which the TMSs of individual vehicles were used. However, when the 30-second-interval aggregated TMS were used, the volume-distance weighted harmonic mean was outstanding. In this study, a radar detector was installed in the Joongbu expressway to collect the SMS. The trajectory of individual vehicles collected from the detector were used to calculate the SMS, which was compared with the estimates using other methodologies selected in this study. As a result, the volume-distance weighted mean was turned out to be close to the SMS. However, as the congestion becomes severe. the deviation between the two speed becomes bigger.

Comparison of Precipitation Distributions in Precipitation Data Sets Representing 1km Spatial Resolution over South Korea Produced by PRISM, IDW, and Cokriging (PRISM, 역거리가중법, 공동크리깅으로 작성한 1km 공간해상도의 남한 강수 자료에서 강수 분포의 비교)

  • Park, Jong-Chul;Kim, Man-Kyu
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.16 no.3
    • /
    • pp.147-163
    • /
    • 2013
  • The purpose of this study is to compare precipitation distributions in precipitation data sets over South Korea produced by three interpolation methods. The differences of precipitation caused by interpolation methods is an important information when the interpolated precipitation data sets were used in researches such as ecological and hydrological modeling as well as regional climate impact studies. In this study, the precipitation data sets were produced by IDW(Inverse Distance Weighting) and Cokriging in this study and the PRISM(Precipitation-elevation Regressions on Independent Slopes Model) data set obtained from Climate Change Information Center of Korea. The spatial resolution of the precipitation data is 1km. As a result, there was a great precipitation difference caused by interpolation methods in data of mountainous watersheds in general. Especially the difference of monthly precipitation was 10~20% or more in the mountainous watersheds near the Military Demarcation Line dividing North and South Korea, Mt. Sobaik, Mt. Worak, Mt. Deogyu, Mt. Jiri and Taeback Mountain Range. It means that a final result of a research can be affected by adopted interpolation method when an interpolated precipitation data set is used in the research for the these study sites.

An Application of Statistical Downscaling Method for Construction of High-Resolution Coastal Wave Prediction System in East Sea (고해상도 동해 연안 파랑예측모델 구축을 위한 통계적 규모축소화 방법 적용)

  • Jee, Joon-Bum;Zo, Il-Sung;Lee, Kyu-Tae;Lee, Won-Hak
    • Journal of the Korean earth science society
    • /
    • v.40 no.3
    • /
    • pp.259-271
    • /
    • 2019
  • A statistical downscaling method was adopted in order to establish the high-resolution wave prediction system in the East Sea coastal area. This system used forecast data from the Global Wave Watch (GWW) model, and the East Sea and Busan Coastal Wave Watch (CWW) model operated by the Korea Meteorological Administration (KMA). We used the CWW forecast data until three days and the GWW forecast data from three to seven days to implement the statistical downscaling method (inverse distance weight interpolation and conditional merge). The two-dimensional and station wave heights as well as sea surface wind speed from the high-resolution coastal prediction system were verified with statistical analysis, using an initial analysis field and oceanic observation with buoys carried out by the KMA and the Korea Hydrographic and Oceanographic Agency (KHOA). Similar to the predictive performance of the GWW and the CWW data, the system has a high predictive performance at the initial stages that decreased gradually with forecast time. As a result, during the entire prediction period, the correlation coefficient and root mean square error of the predicted wave heights improved from 0.46 and 0.34 m to 0.6 and 0.28 m before and after applying the statistical downscaling method.

Machine-printed Numeral Recognition using Weighted Template Matching with Chain Code Trimming (체인 코드 트리밍과 가중 원형 정합을 이용한 인쇄체 숫자 인식)

  • Jung, Min-Chul
    • Journal of Intelligence and Information Systems
    • /
    • v.13 no.4
    • /
    • pp.35-44
    • /
    • 2007
  • This paper proposes a new method of weighted template matching for machine-printed numeral recognition. The proposed weighted template matching, which emphasizes the feature of a pattern using adaptive Hamming distance on local feature areas, improves the recognition rate while template matching processes an input image as one global feature. Template matching is vulnerable to random noises that generate ragged outlines of a pattern when it is binarized. This paper offers a method of chain code trimming in order to remove ragged outlines. The method corrects specific chain codes within the chain codes of the inner and the outer contour of a pattern. The experiment compares confusion matrices of both the template matching and the proposed weighted template matching with chain code trimming. The result shows that the proposed method improves fairly the recognition rate of the machine-printed numerals.

  • PDF

A Spatio-Temporal Variation Pattern of Oiling Status Using Spatial Analysis in Mallipo Beach of Korea (공간분석 기법을 이용한 만리포 유분의 시·공간 변동 패턴 분석)

  • Kim, Tae-Hoon;Choi, Hyun-Woo;Kim, Moon-Koo;Shim, Won-Joon
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.15 no.4
    • /
    • pp.90-103
    • /
    • 2012
  • Mallipo is a representative beach contaminated by Hebei Spirit oil spill accident in December 2007. This study aims to compare the differences of two seasons (winter and summer) for the spatio-temporal variation patterns of oiling status in the whole area and divided five regions of Mallipo beach. In the whole area, the decreasing rate of average TPH (total petroleum hydrocarbon) in winter was twice greater than summer during four years. According to the spatial variation pattern analysis of oiling status using weighted mean center and weighted standard distance, the oil concentration was clustered on southwestern region in winter, however, the TPH was dispersed in the whole area in summer. Temporal variation pattern of TPH in each of Mallipo's five regions showed that TPH had been consistently decreased in winter, but oil concentration had not been changed in summer since 2009 except the southwestern region. Therefore, in order to evaluate and predict the progress of oiling status, it is needed to analyze the spatio-temporal variation pattern of TPH using spatial analysis after separating data into seasons (e.g., winter and summer). In addition, time series analysis is useful in the regional scales through spatial partitioning rather than the whole beach area for the understanding of temporal variation pattern.

Approximate Periods of Strings based on Distance Sum for DNA Sequence Analysis (DNA 서열분석을 위한 거리합기반 문자열의 근사주기)

  • Jeong, Ju Hui;Kim, Young Ho;Na, Joong Chae;Sim, Jeong Seop
    • KIPS Transactions on Software and Data Engineering
    • /
    • v.2 no.2
    • /
    • pp.119-122
    • /
    • 2013
  • Repetitive strings such as periods have been studied vigorously in so diverse fields as data compression, computer-assisted music analysis, bioinformatics, and etc. In bioinformatics, periods are highly related to repetitive patterns in DNA sequences so called tandem repeats. In some cases, quite similar but not the same patterns are repeated and thus we need approximate string matching algorithms to study tandem repeats in DNA sequences. In this paper, we propose a new definition of approximate periods of strings based on distance sum. Given two strings $p({\mid}p{\mid}=m)$ and $x({\mid}x{\mid}=n)$, we propose an algorithm that computes the minimum approximate period distance based on distance sum. Our algorithm runs in $O(mn^2)$ time for the weighted edit distance, and runs in O(mn) time for the edit distance, and runs in O(n) time for the Hamming distance.

The Study on Speaker Change Verification Using SNR based weighted KL distance (SNR 기반 가중 KL 거리를 활용한 화자 변화 검증에 관한 연구)

  • Cho, Joon-Beom;Lee, Ji-eun;Lee, Kyong-Rok
    • Journal of Convergence for Information Technology
    • /
    • v.7 no.6
    • /
    • pp.159-166
    • /
    • 2017
  • In this paper, we have experimented to improve the verification performance of speaker change detection on broadcast news. It is to enhance the input noisy speech and to apply the KL distance $D_s$ using the SNR-based weighting function $w_m$. The basic experimental system is the verification system of speaker change using GMM-UBM based KL distance D(Experiment 0). Experiment 1 applies the input noisy speech enhancement using MMSE Log-STSA. Experiment 2 applies the new KL distance $D_s$ to the system of Experiment 1. Experiments were conducted under the condition of 0% MDR in order to prevent missing information of speaker change. The FAR of Experiment 0 was 71.5%. The FAR of Experiment 1 was 67.3%, which was 4.2% higher than that of Experiment 0. The FAR of experiment 2 was 60.7%, which was 10.8% higher than that of experiment 0.

Optimally Weighted Cepstral Distance Measure for Speech Recognition (음성 인식을 위한 최적 가중 켑스트랄 거리 측정 방법)

  • 김원구
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • 1994.06c
    • /
    • pp.133-137
    • /
    • 1994
  • In this paper, a method for designing an optimal weight function for the weighted cepstral distance measure is proposed. A conventional weight function or cepstral lifter is obtained eperimentally depending on the spectral components to be emphasized. The proposed method minimizes the error between word reference patterns and the traning data. To compare the proposed optimal weight function with conventional function, speech recognition systems based on Dpynamic Time Warping and Hidden Markov Models were constructed to conduct speaker independent isolated word necogination eperiment. Results show that the proposed method gives better performance than conventional weight functions.

  • PDF

Visual Cryptography for Multi Images Using Constant Weight Codes (고정 가중치 부호에 의한 복수 화상용 시각암호)

  • 김미라;박상우;박지환
    • Proceedings of the Korea Institutes of Information Security and Cryptology Conference
    • /
    • 1996.11a
    • /
    • pp.261-271
    • /
    • 1996
  • M.Naor와 A.Shamir의 시각암호는 기존의 비밀 분산법에서 분산/복호시 연산량이 많은 것과는 달리 인간의 시각에 의해서 직접 복호될 수 있는 방식이다. 본 논문에서는 시각암호의 화장 방식인 복수 화상을 숨기는 방식에서 숨기려는 비밀화상의 수가 증가함에 따라 share 크기가 기하 급수적으로 커지는 문제점을 해결하기 위하여 고정 가중치부호의 해밍 거리를 조정하여 share 크기를 줄이는 방법을 제안한다.

  • PDF

Air Temperature Prediction at Higher Temporal and Spatial Resolution in Pyongchang Mountainous Area (일사 수광량 보정에 의한 평창지역 고해상도 기온분포도 작성)

  • 정유란;윤진일;안재훈
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
    • /
    • 2001.06a
    • /
    • pp.153-156
    • /
    • 2001
  • 한 지점의 매시 기온 관측값에는 이 지점의 수평 및 수직 위치, 주변 식생, 하천이나 바다 등, 모든 기온결정인자의 영향이 녹아있다고 볼 수 있다. 만약 지표 특성이 이들 관측지점과 동질적이며, 관측점들의 표고에 의해 그 지형이 정확히 표현될 수 있는 넓은 지역이 있다면, 기존의 거리 역산가중법(Inverse Distance Weighting: IDW)에 의해 내삽되는 기온의 공간변이는 실제 기온의 공간변이와 일치할 것이다.(중략)

  • PDF