• Title/Summary/Keyword: threshold value

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An adaptive resynchronization technique for stream cipher system in HDLC protocol (HDLC 프로토콜에서 운용되는 동기식 스트림 암호 통신에 적합한 적응 난수열 재동기 기법)

  • 윤장홍;황찬식
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.9
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    • pp.1916-1932
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    • 1997
  • The synchronous stream cipher which require absoulte clock synchronization has the problem of synchronization loss by cycle slip. Synchronization loss makes the state which sender and receiver can't communicate with each other and it may break the receiving system. To lessen the risk, we usually use a continuous resynchronization method which achieve resynchronization at fixed timesteps by inserting synchronization pattern and session key. While we can get resynchronization effectively by continuous resynchroniation, there are some problems. In this paper, we proposed an adaptive resynchronization algorithm for cipher system using HDLC protocol. It is able to solve the problem of the continuous resynchronization. The proposed adaptive algorithm make resynchronization only in the case that the resynchronization is occurred by analyzing the address field of HDLC. It measures the receiving rate of theaddress field in the decision duration. Because it make resynchronization only when the receiving rate is greateer than the threshold value, it is able to solve the problems of continuous resynchronization method. When the proposed adaptive algorithm is applied to the synchronous stream cipher system in packet netork, it has addvance the result in R_e and D_e.

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Segmentation Method of Overlapped nuclei in FISH Image (FISH 세포영상에서의 군집세포 분할 기법)

  • Jeong, Mi-Ra;Ko, Byoung-Chul;Nam, Jae-Yeal
    • The KIPS Transactions:PartB
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    • v.16B no.2
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    • pp.131-140
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    • 2009
  • This paper presents a new algorithm to the segmentation of the FISH images. First, for segmentation of the cell nuclei from background, a threshold is estimated by using the gaussian mixture model and maximizing the likelihood function of gray value of cell images. After nuclei segmentation, overlapped nuclei and isolated nuclei need to be classified for exact nuclei analysis. For nuclei classification, this paper extracted the morphological features of the nuclei such as compactness, smoothness and moments from training data. Three probability density functions are generated from these features and they are applied to the proposed Bayesian networks as evidences. After nuclei classification, segmenting of overlapped nuclei into isolated nuclei is necessary. This paper first performs intensity gradient transform and watershed algorithm to segment overlapped nuclei. Then proposed stepwise merging strategy is applied to merge several fragments in major nucleus. The experimental results using FISH images show that our system can indeed improve segmentation performance compared to previous researches, since we performed nuclei classification before separating overlapped nuclei.

Development of Sequential Sampling Plan for Bemisia tabaci in Paprika Greenhouses (파프리카 온실에서 담배가루이의 축차표본조사법 개발)

  • Choi, Wonseok;Park, Jung-Joon
    • Korean journal of applied entomology
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    • v.54 no.3
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    • pp.159-167
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    • 2015
  • In order to establish B. tabaci control in paprika greenhouses a fixed-precision-level sampling plan was developed. The sampling plan consisted of spatial distribution analysis, a sampling stop line, and decision making. Sampling was conducted simultaneously in two independent greenhouses (GH 1, GH 2). GH 1 and 2 were surveyed every week for 22 consecutive weeks, using 19 sampling locations in GH 1 and 9 sampling locations in GH 2. The plant in both greenhouses were divided into top (180-220 cm from the ground), middle (80-120 cm from the ground) and bottom (30-70 cm from the ground) sections and B. tabaci adults and pupae were observed on three paprika leaves at each position and recorded separately. GH 2 data were used to validate the fixed-precision sampling plan, which was developed using GH 1 data. In this study, spatial distribution analysis was performed using Taylor's power law with the pooled data of the top and bottom position (B. tabaci adults), and the middle and bottom positions (B. tabaci pupae), based on a 1-leaf sampling unit. Decision making was undertaken using the maximum of action threshold in accordance with previously published method, and the value was decided by the price of the plants. Using the results obtained in the greenhouse, simulated validation of the developed sampling plan by RVSP (Resampling Validation for Sampling Plan) indicated a reasonable level of precision.

Effectiveness of Edge Selection on Mobile Devices (모바일 장치에서 에지 선택의 효율성)

  • Kang, Seok-Hoon
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.7
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    • pp.149-156
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    • 2011
  • This paper proposes the effective edge selection algorithm for the rapid processing time and low memory usage of efficient graph-based image segmentation on mobile device. The graph-based image segmentation algorithm is to extract objects from a single image. The objects are consisting of graph edges, which are created by information of each image's pixel. The edge of graph is created by the difference of color intensity between the pixel and neighborhood pixels. The object regions are found by connecting the edges, based on color intensity and threshold value. Therefore, the number of edges decides on the processing time and amount of memory usage of graph-based image segmentation. Comparing to personal computer, the mobile device has many limitations such as processor speed and amount of memory. Additionally, the response time of application is an issue of mobile device programming. The image processing on mobile device should offer the reasonable response time, so that, the image segmentation processing on mobile should provide with the rapid processing time and low memory usage. In this paper, we demonstrate the performance of the effective edge selection algorithm, which effectively controls the edges of graph for the rapid processing time and low memory usage of graph-based image segmentation on mobile device.

Chromatic adaptation model for the variations of the luminance of the same chromaticity illuminants (동일 색도 광원의 휘도 변화에 따른 색 순응 모델)

  • Kim Eun-Su;Jang Soo-Wook;Lee Sung-Hak;Sohng Kyu-lk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.4 s.304
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    • pp.31-38
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    • 2005
  • In this paper, we propose the chromatic adaptation models (CAM) for the variations of the luminance levels. A chromatic adaptation model, CAM$\Delta$Y , is proposed according to the change of luminance level under the same illuminants. The proposed model is obtained by the transform the test colors of the high luminance into the corresponding colors of the low luminance. In the proposed model, the optimal coefficients are obtained from the corresponding colors data of the Breneman's experiments. In the experimental results, we confined that the chromaticity errors, $\Delta$u'v', between the predicted colors by the proposed model and the corresponding colors of the Breneman's experiments are 0.004 in u'v' chromaticity coordinates. The prediction performance of the proposed model is excellent because this error is the threshold value that two adjacent color patches can be distinguished. Additionally, we also propose equal-whiteness CCT curves (EWCs) by CAM$\Delta$Y according to the luminance levels of the surround viewing conditions. And the proposed EWCs can be used as the theoretical standard which determines the reference white of the color display devices.

A Study On Radiation Detection Using CMOS Image Sensor (CMOS 이미지 센서를 사용한 방사선 측정에 관한 연구)

  • Lee, Joo-Hyun;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.19 no.2
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    • pp.193-200
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    • 2015
  • In this paper, we propose the radiation measuring algorithm and the device composition using CMOS image sensor. The radiation measuring algorithm using CMOS image sensor is based on the radiation particle distinguishing algorithm projected to the CMOS image sensor and accumulated and average number of pixels of the radiation particles projected to dozens of images per second with CMOS image sensor. The radiation particle distinguishing algorithm projected to the CMOS image sensor measures the radiation particle images by dividing them into R, G and B and adjusting the threshold value that distinguishes light intensity and background from the particle of each image. The radiation measuring algorithm measures radiation with accumulated and average number of radiation particles projected to dozens of images per second with CMOS image sensor according to the preset cycle. The hardware devices to verify the suggested algorithm consists of CMOS image sensor and image signal processor part, control part, power circuit part and display part. The test result of radiation measurement using the suggested CMOS image sensor is as follows. First, using the low-cost CMOS image sensor to measure radiation particles generated similar characteristics to that from measurement with expensive GM Tube. Second, using the low-cost CMOS image sensor to measure radiation presented largely similar characteristics to the linear characteristics of expensive GM Tube.

Evaluating Soil Respiration as Indicator of Heavy Metal Pollution in Agricultural Field

  • Choi, Won-Suk;Hong, Young-Kyu;Min, Kyung-Jun;Kim, Kwang-Jin;Kim, Sung-Chul
    • Korean Journal of Soil Science and Fertilizer
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    • v.50 no.5
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    • pp.472-481
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    • 2017
  • Agricultural field near at the abandoned metal mine and industrial area has a high possibility to be polluted by heavy metals. However, concern about chemical properties including heavy metal concentration has been increased and biological properties such as soil respiration has been minimal in heavy metal polluted field. Therefore, main objective of this research was to evaluate soil respiration as an indicator of heavy metal pollution in agricultural field. Total of 60 sampling sites including each 30 sites of abandoned metal mine and industrial area were selected and heavy metal concentration, soil respiration, and chemical properties were measured. Results showed that heavy metal concentration in metal mine area was ranged Cu: $6.21~85.23mg\;kg^{-1}$, Pb: $23.84{\sim}1,044.72mg\;kg^{-1}$, As: $1.88{\sim}691.44mg\;kg^{-1}$, Zn: $18.72{\sim}527.55mg\;kg^{-1}$, Cd: $0.58{\sim}4.27mg\;kg^{-1}$, and Cu: $0.29{\sim}30.62mg\;kg^{-1}$, Pb: $4.41{\sim}19.77mg\;kg^{-1}$, As: $2.23{\sim}11.76mg\;kg^{-1}$, Zn $39.98{\sim}109.59mg\;kg^{-1}$, Cd $0.29{\sim}0.57mg\;kg^{-1}$ for industrial area respectively. While no sampling site was exceed the threshold value of each heavy metals in industrial field, metal mine area was highly polluted with Pb, As, Zn, and Cd. Soil respiration in the metal mine and industrial area was ranged $12.05{\sim}299.80mg\;O_2\;kg^{-1}$ and $27.68{\sim}330.94mg\;O_2\;kg^{-1}$, respectively. Correlation analysis between heavy metal concentration in soil and soil respiration showed that negative correlation was observed in metal mine area while no correlation was observed in industrial area. This result might indicate that as heavy metal concentration was increased, microbial activity in soil was decreased resulting decrease of soil respiration rate. Overall, soil respiration can be used as indicator of heavy metal pollution in soil and more biological properties need to be evaluated to better understand heavy metal pollution in soil.

A Comparative Study of Endotracheal Aspirates and Protected Specimen Brush in the Quantitative Cultures of the Ventilator-Associated Pneumonia (기계호흡기 관련 폐렴환자의 정량적 배양에 있어서 Endotracheal Aspirates과 Protected Specimen Brush의 비교 관찰)

  • Roo, Kyoung-Ryeol;Kim, Min-Gu;Kim, Gi-Yang;Jung, Ho-Gyeong;Park, Young-Ho;Kang, Byeng-Sun;Kim, Ho-Chul;Hwang, Young-Sil
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.5
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    • pp.737-743
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    • 1995
  • Background: Pneumonia is a frequent complication in patients undergoing mechanical ventilation, Quantitative culture of protected specimen brush(PSB) have shown satisfactory diagnostic accuracy for the diagnosis of ventilator-associated pneumonia. However PSB method is invasive, expensive, and require a bronchoscopic procedure. But endotracheal aspiration(EA) is simple and less expensive. The purpose of our study was to investigate the diagnosic value of EA quantitative cultures. Method: We studied 15 cases of ventilator-associated pneumonia(for >72h of mechanical ventilation) patients. Patients were divided into two diagnostic categories. Group I was the patients who were suspicious of clinical pneumonia, Group II was the patients for control. The obtained samples by EA and PSB were homogenized for quantitative culture with a calibrated loop method in all patients. Result: Using $10^3cfu/ml$, $10^5cfu/ml$ as threshold in quantitative culture of PSB, EA respectively, we found that EA quantitative cultures represented a relatively sentive(70%) and relatively specific (60%) method to diagnose the ventilator-associated pneumonia. Conclusion: Although EA quantitative cultures are less specific than PSB for diagnosing ventilator-associated pneumonia. EA quantitative cultures correlated with PSB quantitative culture in patients with clinical pneumonia and may be used to treat these patients when bronchoscopic procedures are not available.

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Swell Effect Correction of Sub-bottom Profiler Data with Weak Sea Bottom Signal (해저면 신호가 약한 천부해저지층 탐사자료의 너울영향 보정)

  • Lee, Ho-Young;Koo, Nam-Hyung;Kim, Wonsik;Kim, Byoung-Yeop;Cheong, Snons;Kim, Young-Jun;Son, Woohyun
    • Geophysics and Geophysical Exploration
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    • v.18 no.4
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    • pp.181-196
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    • 2015
  • A 3.5 kHz or chirp sub-bottom profiling survey is widely used in the marine geological and engineering purpose exploration. However, swells in the sea degrade the quality of the survey data. The horizontal continuity of profiler data can be enhanced and the quality can be improved by correcting the influence of the swell. Accurate detection of sea bottom location is important in correcting the swell effect. In this study, we tried to pick sea bottom locations by finding the position of crossing a threshold of the maximum value for the raw data and transformed data of envelope or energy ratio. However, in case of the low-quality data where the sea bottom signals are not clear due to sea wave noise, automatic sea bottom detection at the individual traces was not successful. We corrected the mispicks for the low quality data and obtained satisfactory results by picking a sea bottom within a range considering the previous average of sea bottom, and excluding unreliable big-difference picks. In case of trace by trace picking, fewest mispicks were found when using energy ratio data. In case of picking considering the previous average, the correction result was relatively satisfactory when using raw data.

Properties of ZnS:Cu,Cl Thick Film Electroluminescent Devices by Screen Printing Method (스크린인쇄법에 의한 ZnS:Cu,Cl 후막 전계발광소자의 특성)

  • No, Jun-Seo;Yu, Su-Ho;Jang, Ho-Jeong
    • Korean Journal of Materials Research
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    • v.11 no.6
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    • pp.448-452
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    • 2001
  • The ZnS:Cu,Cl thick film electroluminescent devices with the stacking type(separated with phosphors and insulator layers) and the composite type (mixed with phosphor and insulator materials) emission layers were fabricated on ITO/glass substrates by the screen printing methods. The opical and electrical properties were investigated as fundations of applied voltages and frequencies. In the stacking type, the luminance was about 58 cd/$\m^2$ at the applied voltage of 400Hz, 200V and increased to 420 cd/$\m^2$ with increasing the frequency to 30Hz. For the composite type devices, the threshold voltage was 45V and the maximum luminance was 670 cd/$\m^2$ at the driving condition of 200V, 30Hz. The value of luminance of the composite type device showed 1.5 times higher than that of stacking type device. The main emission peak was 512 nm of bluish-green color at 1Hz frequency below and shifted to 452 nm in the driving frequency over 5Hz showing the blue omission color. There were no distinct differences of the main emission peaks and color coordinate for both samples.

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