• Title/Summary/Keyword: height estimation

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The Characteristics and Biomass Distribution in Crown of Larix olgensis in Northeastern China

  • Chen, Dongsheng;Li, Fengri
    • Journal of Korean Society of Forest Science
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    • v.99 no.2
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    • pp.204-212
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    • 2010
  • This study was performed in 22 unthinned Larix olgensis plantations in northeast China. Data were collected on 95 sample trees of different canopy positions and the diameter at breast height ($d_{1.3}$) ranged from 5.7 cm to 40.2 cm. The individual tree models for the prediction of vertical distribution of live crown, branch and needle biomass were built. Our study showed that the crown, branch and needle biomass distributions were most in the location of 60% crown length. These results were also parallel to previous crown studies. The cumulative relative biomass of live crown, branch and needle were fitted by the sigmoid shape curve and the fitting results were quite well. Meanwhile, we developed the crown ratio and width models. Tree height was the most important predictor for crown ratio model. A negative competition factor, ccf and bas which reflected the effect of suppression on a tree, reduced the crown ratio estimates. The height-diameter ratio was a significant predictor. The higher the height-diameter ratio, the higher crown ratio is. Diameter at breast height is the strongest predictor in crown width model. The models can be used for the planning of harvesting operations, for the selection of feasible harvesting methods, and for the estimation of nutrient removals of different harvesting practices.

Deterioration Diagnostic Techniques for Power Facilities by Analyzing Pulse-Height of leakage current (누설전류 파고분석에 의한 전력설비의 열화진단 기술)

  • 한주섭;김명진;손원진;길경석
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.10a
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    • pp.367-370
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    • 2001
  • This paper proposes a new deterioration diagnostic technique for power facilities by analyzing the pulse-height analysis of leakage current. Until now, various deterioration diagnostic techniques to prevent power system failures by deterioration of power facilities are suggested, and most of which measures leakage current amplitude only as a estimation parameter. In this experiment, it is known that the pulse heights of the leakage current are increased according to deterioration progress as well as there comes remarkable changes in pulse height distribution thereto. Therefore, the use of pulse height distribution in deterioration diagnostic technique makes more accurate diagnosis than the conventional method by using only leakage current value. From the application test, it is confirmed that the proposed technique has sufficient performance to diagnose deterioration of power facilities.

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A Study on the Changes of Vertical height in Teeth and Alveolar Bone with Age (증령에 따른 치아 및 치조골의 고경 변화에 관한 연구)

  • Se-Sook Kang;Kyung-Soo Han
    • Journal of Oral Medicine and Pain
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    • v.13 no.1
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    • pp.13-21
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    • 1988
  • The author studied the vertical height of tooth crown and the amounts of alveolar bone resorption with age. All 84 subjects(44 male, 40female) who visited Dental hospital of Wonkwang University with no history of sever periodontal disease and no experience of periodontal surgery. 84 subject were divided into 3 groups by age, that is, group I(28-32yrs), group II(38-42yrs), and group III(48-52yrs). Informal radiogram with bite wing film(horizontal angulation : $0^{\circ}$, vertical angulation : $+5^{\circ}~+10^{\circ}$) were taken on premolar and molar area. The distances from cusp tip to cementoenamel junction (vertical height of tooth crown) and from cementoenamel junction alveolar crest(amount of alveolar bone resorption) were measured, and then recorded data from 946 teeth were statistically analysed. This study was undertaken to obtain the data for age estimation by the changes of tooth crown height and alveolar bone resorption in the point of forensic odontology. The obtained results were as follows : 1. The average crown height of mandibular right 1st. molar was 7.1mm in group I, 6.7mm in group II, and 6.6mm group III, and the average amount of alveolar bone resorption on mandibular right 1st. molar were 1.8mm in group I, 2.5mm in group II, and 3.0mm in group III. Ratio of tooth crown height to amount of alveolar bone resorption was 4.0:1 in groupI, 2.7:1 in group II, and 2.2:1 in group III, the ratio was decreased with age. 2. In comparison with upper teeth and lower teeth in ipsilateral side, the average value of tooth crown height and amount of alveolar bone resorption were slightly higher in upper arch than those in lower arch, but there was not a statistically significant difference. 3. The ratio of height of tooth crown to amount of alveolar bone resorption was decreased with age, and which depended mainly upon the change of amount of alveolar bone resorption rather than the change of tooth crown height.

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Error Characteristics of Ship Radiated Noise Estimation by Sea Surface Scattering Effect (해면 산란효과에 의한 선박 방사소음 추정치 오차)

  • Park, Kyu-Chil;Park, Jihyun;Seo, Chulwon;Choi, Jae Yong;Lee, Phil-Ho;Yoon, Jong Rak
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.6
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    • pp.563-573
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    • 2013
  • The ship radiated noise level fluctuates by the interference between direct and reflected paths. The effect of sea surface reflection path on interference depends strongly on sea surface roughness. This paper describes error characteristics of ship acoustic signature estimation by sea surface scattering effect. The coherent reflection coefficient which explains a magnitude of sea surface scattering and its resultant interference acoustic field is analyzed quantitatively as a function of a grazing angle, effective surface height, frequency, source-receiver range and depths of source and receiver. Theoretical interference acoustic field is compared with experimental result for two different sea surfaces and five different frequencies by changing source-receiver range. It is found that both matches well each other and a magnitude of interference acoustic field is decreasing by increasing a grazing angle, effective surface height, frequency, and depths of source and receiver and decreasing source-receiver range. For given experimental conditions, the transmission anomaly which is a bias error of ship acoustic signature estimation, is about a range of 1~3 dB. The bias error of an existing ship radiated noise measurement system is also analyzed considering wind speed, source depth and frequency.

Development of Blood Pressure Estimation Methods Using The PPG and ECG Sensors (PPG 및 ECG 센서를 이용한 혈압추정 기법 개발)

  • Park, Hyun-Moon;Lee, Jung-Chul;Hwang, Tae-Ho
    • The Journal of the Korea institute of electronic communication sciences
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    • v.14 no.6
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    • pp.1257-1264
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    • 2019
  • The traditional cuff-based method for BP(Blood Pressure) measurement is not suitable for continuous real-time BP measurement techniques. For this reason, the previous studies estimated various blood pressures by fusion with the electrocardiography (ECG) and photoplethysmogram (PPG) sensor signals. However, conventional techniques based on PPG bio-sensing measurement face many challenging issues such as noisy supply fluctuation, small pulsation, and drifting non-pulsatile. This paper proposed a novel BP estimation methods using PPG and ECG sensors, which can be derived from the relationship between PPG and ECG using PTT(Pulse Transit Time) and PWV(Pulse Wave Velocity). Unlike conventional height ratio features, which are extracted on the basis of the peaks in the PPG and ECG waveform. The proposed method can be reliably obtained even if there are missing peaks among the sensed PPG signal. The increased reliability comes from periodical estimation of the peak-to-peak interval time using ECG and PPG. After 250,000 times trials of the blood pressure measurement, the proposed estimation technique was verified with the accuracy of ±28.5% error, compared to a commercialized BP device.

A Comparison and Analysis of the Levee Height Determination Methods in Korea and the USA (우리나라와 미국의 제방고 산정 기법에 대한 비교 분석)

  • Kang, Tae-Uk;Lee, Sang-Ho;Yu, Kwon-Kyu
    • Journal of Korea Water Resources Association
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    • v.44 no.6
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    • pp.497-510
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    • 2011
  • A levee height is determined by adding a deterministic freeboard to a flood water level in Korea. In the USA, a levee height is determined by choosing a value conditionally among the freeboard criteria and the levels resulted from a probabilistic method. The probabilistic method adopts a conditional non-exceedance probability (CNP) which is the probability that the target stage will not be exceeded given a specific flood event. The purpose of the study is to compare Korean criterion for levee height estimation with that of the USA. Levee heights were determined according to the above two criteria at twenty-five cross sections in five streams. The results show that Korean criterion on average yields levee heights 20 cm higher than those calculated by the criterion of the USA. The larger the flood discharges become, the higher the levee height differences are usually. It is caused by the freeboard estimation criterion of Korea that the larger design flood is, the higher freeboard is given. Korean criterion, however, resulted in lower levee heights for smaller streams than those by the criterion of the USA. To sum it up, the Korean levee height criteria can result in overestimation or underestimation depending on flood discharge amount, being compared with the criteria of the USA. The Korean freeboard especially needs to be increased for smaller flood discharges.

A Study on Growth of Children with Atopic Dermatitis (아토피 피부염 환아의 성장에 관한 임상적 연구)

  • Lee, Seoung-Hee;Kim, Jang-Hyun
    • The Journal of Pediatrics of Korean Medicine
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    • v.16 no.2
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    • pp.163-170
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    • 2002
  • Background: Owing to stress of external appearance and bad sleeping by itching, children with atopic dermatitis grow slowly. Object: The purpose of this study is estimation of growth degree on children with atopic dermatitis Method: During I year from 2001 till 2002, it became the object of studing that 45 children with atopic dermatitis and random sample 45 children without atopic dermatitis, without another disease related to growth from 2 years to 10 years in Dep. of Pediatrics, Dongguk university Bundang Oriental Hospital. Result: Height percent of children with atopic dermatitis is more lower than Height percent of children without atopic dermatitis out of considering for the distinction of sex and age. The more atopic dermatitis is severe, the more height percent of children with atopic dermatitis is lower Conclusion: Atopic dermatitis is related to the growth on children.

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Development of Relationship between Air Quality and Rain Acidity (대기질 - 강우산성도 관계식의 개발)

  • 구자공;유동준
    • Journal of Korean Society for Atmospheric Environment
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    • v.2 no.3
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    • pp.45-51
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    • 1986
  • The simple and precise model for the estimation of rain acidity from the ambient air quality was developed using the theory of wet scrubber and the chemical equilibria of $SO_2, CO_2, and H_2O$ system. From the measured mixing height, and from the developed relationship between NTU (=number of transfer units) and the concentration of $SO_2$(aq) in rain drops, the HTU (= height equivalent to one transfer unit, i.e. mass transfer resistance) was estimated, and validated with the field-measured data. In Seoul, Korea where the effect of $SO_2$ on rainfall acidity is as high as 84% and the average mixing height is 1 km, the average HTU of $SO_2$ system was found to be 191.5m. The important parameters affecting HTU were identified as rainfall intensity and initial ambient concentration of $SO_2$, and their effects on the value of overall volumetric mass transfer coefficient were quantified.

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A New Technology for Optimization of Bead Height Using ANN

  • Kim, Ill-Soo;Son, Joon-Sik;Sung, Back-Sub;Lee, Chang-Woo;Cha, Yong-Hoon
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2001.04a
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    • pp.208-213
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    • 2001
  • Objective of this paper is to develop a new approach involving the use of an Artificial Neural Network(ANN) and multiple regression methods in the prediction of process parameters on bead height for GMA welding process. Using a series of robotic are welding, multi-pass butt welds carried out in order to verify the performance of the neural network estimator and multiple regression methods. To verify the developed system, the design parameters of the neural network estimator are selected from an estimation error analysis. The experimental results show that the proposed models can predict the bead height with reasonable accuracy and guarantee the uniform weld quality.

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Height Estimation of pedestrian based on image (영상기반 보행자 키 추정 방법)

  • Kim, Sung-Min;Song, Jong-Kwan;Yoon, Byung-Woo;Park, Jang-Sik
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.9
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    • pp.1035-1042
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    • 2014
  • Object recognition is one of the key technologies of the monitoring system for the prevention of various intelligent crimes. The height is one of the physical information of a person, and it may be important information for identification of the person. In this paper, a method which can detect pedestrians from CCTV images and estimate the height of the detected objects, is proposed. In this method, GMM (Gaussian Mixture Model) method was used to separate the moving object from the background and the pedestrian was detected using the conditions such as the width-height ratio and the size of the candidate objects. The proposed method was applied to the CCTV video, and the height of the pedestrian at far-distance, middle- distance, near-distance was estimated for the same person, and the accuracy was evaluated. Experimental results showed that the proposed method can estimate the height of the pedestrian as the accuracy of 97% for the short-range, 98% for the medium-range, and more than 97% for the far-range. The image sizes for the same pedestrian are different as the position of him in the image, it is shown that the proposed algorithm can estimate the height of pedestrian for various position effectively.