• 제목/요약/키워드: error performance

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Assessment of Carbon Stock and Uptake by Estimation of Stem Taper Equation for Pinus densiflora in Korea (우리나라 소나무의 수간곡선식 추정에 의한 탄소저장량 및 흡수량 산정)

  • Kang, Jin-Taek;Son, Yeong-Mo;Jeon, Ju-Hyeon;Lee, Sun-Jeoung
    • Journal of Climate Change Research
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    • v.8 no.4
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    • pp.415-424
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    • 2017
  • This study was conducted to estimate carbon stocks of Pinus densiflora with drawing volume of trees in each tree height and DBH applying the suitable stem taper equation and tree specific carbon emission factors, using collected growth data from all over the country. Information on distribution area, tree age, tree number per hectare, tree volume and volume stocks were obtained from the $5^{th}$ National Forest Inventory (2006~2010) and Statistical yearbook of forest (2016), and method provided in IPCC GPG was applied to estimate carbon stock and uptake. Performance in predicting stem diameter at a specific point along a stem in Pinus densiflora by applying Kozak's model, $d=a_{1}DBH^{a_2}a_3^{DBH}X^{b_{1}Z^2+b_2ln(Z+0.001)+b_3\sqrt{Z}+b_4e^z+b_5(\frac{DBH}{H})}$, which is well known equation in stem taper estimation, was evaluated with validations statistics, Fitness Index, Bias and Standard Error of Bias. Consequently, Kozak's model turned out to be suitable in all validations statistics. Stem volume table of P. densiflora was derived by applying Kozak's model and carbon stock tables in each tree height and DBH were developed with country-specific carbon emission factors ($WD=0.445t/m^3$, BEF = 1.445, R = 0.255) of P. densiflora. As the results of analysis in carbon uptake for each province, the values were high with Gangwon-do $9.4tCO_2/ha/yr$, Gyeongsandnam-do and Gyeonggi-do $8.7tCO_2/ha/yr$, Chungcheongnam-do $7.9tCO_2/ha/yr$ and Gyeongsangbuk-do $7.8tCO_2/ha/yr$ in order, and Jeju-do was the lowest with $6.8tC/ha/yr$. Total carbon stocks of P. densiflora were 127,677 thousands tC which is 25.5% compared with total percentage of forest and carbon stock per hectare (ha) was $84.5tC/ha/yr$ and $7.8tCO_2/ha/yr$, respectively.

Modeling and Simulation for Predicting the Impact of Hydraulic Breaker (유압 브레이커의 충격량 예측을 위한 모델링과 해석)

  • Kim, Sung-Hyun;Chung, Jaeho;Baek, Dong-Cheon;Park, Jong-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.2
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    • pp.741-749
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    • 2019
  • A hydraulic breaker attached to an excavator is a kind of constructuion equipment which is used for the disassembling of buildings, crashing road pavement, breaking rocks at quarry and etc. Therefore, the performance of the hydraulic breaker is mainly evaluated by the impact quantity and impact efficiency, which is an important factor for both the manufacturer and the user. In this paper, modeling and simulation for the prediction of the impact of the hydraulic breaker was conducted according to hydraulic pressure area and operating conditions of the hydraulic valve and piston using the commercial tools SimulationX for the 20ton hydraulic breaker which is mainly used in construction site. In order to verify the reliability of modeling and simulation, the results of previous experimental studies were compared and verified. The results of this study are expected to be useful for predicting the impact of the hydraulic breaker at the design stage before manufacturing and for studying parameters for improving the impact quantity. In addition, the manufacturer predicts that the development time and cost will be reduced through trial and error prevention by predicting the impact of the hydraulic breaker through the results of this paper.

Development of Enhanced DAP(Dose Area Product) (성능이 향상된 면적선량계(DAP) 개발)

  • Lee, Young-Ji;Lee, Sang-Heon;Lee, Seung-Ho
    • Journal of IKEEE
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    • v.23 no.2
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    • pp.739-742
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    • 2019
  • In this paper, we propose enhanced DAP(Dose Area Product). The development of enhanced DAP proposed in this paper has optimized the area dose meter that was developed previously. The development of enhanced DAP performed Optimized design of charge integrator and ADC circuit, optimization of line transceiver for RS-485 communication, optimization of display circuit, and optimization of PC-based control program for interlocking and aging. As a result of evaluating the performance of the proposed system in an accredited testing laboratory, Radiation dose dependence and Radiation quality dependence were measured to be 4.2%, which is below ${\pm}15%$ of international standard. Energy range/Tube voltage was confirmed in the range of 30~150kV. The sensitivity difference between sensor field and sensor field area dose sensitivity was measured to be 4.3%, and it was confirmed that it operates normally under ${\pm}15%$ of international standard. In order to measure the reproducibility of the area dosimeter, it was confirmed that it was 0% and it was operated normally at less than 2% of IEC60580 recommendation. Digital resolution was confirmed to be a minimum unit of $0.01{\mu}Gy{\cdot}m^2$ within the error range for the reference dose per hour.

Mathematical Models to Describe the Kinetic Behavior of Staphylococcus aureus in Jerky

  • Ha, Jimyeong;Lee, Jeeyeon;Lee, Soomin;Kim, Sejeong;Choi, Yukyung;Oh, Hyemin;Kim, Yujin;Lee, Yewon;Seo, Yeongeun;Yoon, Yohan
    • Food Science of Animal Resources
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    • v.39 no.3
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    • pp.371-378
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    • 2019
  • The objective of this study was to develop mathematical models for describing the kinetic behavior of Staphylococcus aureus (S. aureus) in seasoned beef jerky. Seasoned beef jerky was cut into 10-g pieces. Next, 0.1 mL of S. aureus ATCC13565 was inoculated into the samples to obtain 3 Log CFU/g, and the samples were stored aerobically at $10^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$ for 600 h. S. aureus cell counts were enumerated on Baird Parker agar during storage. To develop a primary model, the Weibull model was fitted to the cell count data to calculate Delta (required time for the first decimal reduction) and ${\rho}$ (shape of curves). For secondary modeling, a polynomial model was fitted to the Delta values as a function of storage temperature. To evaluate the accuracy of the model prediction, the root mean square error (RMSE) was calculated by comparing the predicted data with the observed data. The surviving S. aureus cell counts were decreased at all storage temperatures. The Delta values were longer at $10^{\circ}C$, $20^{\circ}C$, and $25^{\circ}C$ than at $30^{\circ}C$ and $35^{\circ}C$. The secondary model well-described the temperature effect on Delta with an $R^2$ value of 0.920. In validation analysis, RMSE values of 0.325 suggested that the model performance was appropriate. S. aureus in beef jerky survives for a long period at low storage temperatures and that the model developed in this study is useful for describing the kinetic behavior of S. aureus in seasoned beef jerky.

White striping degree assessment using computer vision system and consumer acceptance test

  • Kato, Talita;Mastelini, Saulo Martiello;Campos, Gabriel Fillipe Centini;Barbon, Ana Paula Ayub da Costa;Prudencio, Sandra Helena;Shimokomaki, Massami;Soares, Adriana Lourenco;Barbon, Sylvio Jr.
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.7
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    • pp.1015-1026
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    • 2019
  • Objective: The objective of this study was to evaluate three different degrees of white striping (WS) addressing their automatic assessment and customer acceptance. The WS classification was performed based on a computer vision system (CVS), exploring different machine learning (ML) algorithms and the most important image features. Moreover, it was verified by consumer acceptance and purchase intent. Methods: The samples for image analysis were classified by trained specialists, according to severity degrees regarding visual and firmness aspects. Samples were obtained with a digital camera, and 25 features were extracted from these images. ML algorithms were applied aiming to induce a model capable of classifying the samples into three severity degrees. In addition, two sensory analyses were performed: 75 samples properly grilled were used for the first sensory test, and 9 photos for the second. All tests were performed using a 10-cm hybrid hedonic scale (acceptance test) and a 5-point scale (purchase intention). Results: The information gain metric ranked 13 attributes. However, just one type of image feature was not enough to describe the phenomenon. The classification models support vector machine, fuzzy-W, and random forest showed the best results with similar general accuracy (86.4%). The worst performance was obtained by multilayer perceptron (70.9%) with the high error rate in normal (NORM) sample predictions. The sensory analysis of acceptance verified that WS myopathy negatively affects the texture of the broiler breast fillets when grilled and the appearance attribute of the raw samples, which influenced the purchase intention scores of raw samples. Conclusion: The proposed system has proved to be adequate (fast and accurate) for the classification of WS samples. The sensory analysis of acceptance showed that WS myopathy negatively affects the tenderness of the broiler breast fillets when grilled, while the appearance attribute of the raw samples eventually influenced purchase intentions.

Reproducing Rhythmic Idioms: A Comparison Between Healthy Older Adults and Older Adults With Mild Cognitive Impairment (리듬꼴에 따른 건강 노인과 경도인지장애 노인의 리듬 재산출 수행력 비교)

  • Chong, Hyun Ju;Lee, Eun Ji
    • Journal of Music and Human Behavior
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    • v.16 no.1
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    • pp.73-88
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    • 2019
  • This research was conducted to compare the rhythm reproduction abilities between older adults with and without mild cognitive impairment (MCI) and analyze the abilities depending on the rhythm idiom. Participants between 60-85 years of age were recruited from senior community centers, dementia prevention centers, and senior welfare centers. A total of 57 participants were included in this study: 27 diagnosed with MCI and 30 healthy older adults (HOA). The experiment was conducted individually in a private room in which a participant was given random binary time rhythm idioms and instructed to reproduce the rhythmic idioms with finger tapping. Each participant's beat production was recorded with the Beat Processing Device (BPD) for iPad. BPD calculated rhythm reproduction as measured through rhythm ratio and error among beats. Results showed marginal differences between the two groups in terms of mean scores of rhythm reproduction abilities. In terms of the rhythm ratio among beats, both groups' highest rhythm reproduction rate was for <♩ ♩>, and their lowest reproduction rate was for <♩. ♪>. In conclusion, there was no significant difference in rhythm reproduction ability between the HOA and MCI groups. However, the study found an interesting result related to performance level of rhythmic idioms. This result provides therapeutic insight for formulating rhythm tasks for older adults.

Implementation of 3D Road Surface Monitoring System for Vehicle based on Line Laser (선레이저 기반 이동체용 3차원 노면 모니터링 시스템 구현)

  • Choi, Seungho;Kim, Seoyeon;Kim, Taesik;Min, Hong;Jung, Young-Hoon;Jung, Jinman
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.6
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    • pp.101-107
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    • 2020
  • Road surface measurement is an essential process for quantifying the degree and displacement of roughness in road surface management. For safer road surface management and quick maintenance, it is important to accurately measure the road surface while mounted on a vehicle. In this paper, we propose a sophisticated road surface measurement system that can be measured on a moving vehicle. The proposed road surface measurement system supports more accurate measurement of the road surface by using a high-performance line laser sensor. It is also possible to measure the transverse and longitudinal profile by matching the position information acquired from the RTK, and the velocity adaptive update algorithm allows a manager to monitor in a real-time manner. In order to evaluate the proposed system, the Gocator laser sensor, MRP module, and NVIDIA Xavier processor were mounted on a test mobile and tested on the road surface. Our evaluation results demonstrate that our system measures accurate profile base on the MSE. Our proposed system can be used not only for evaluating the condition of roads but also for evaluating the impact of adjacent excavation.

Sex Differences in Episodic Memory and Spatial Cognition in Healthy Younger Adults (젊은 성인의 성별에 따른 일화기억과 공간인지의 차이)

  • Kim, Seonkyeom;Park, Jinyoung;Park, Jin-Hyuck
    • Therapeutic Science for Rehabilitation
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    • v.10 no.1
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    • pp.105-114
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    • 2021
  • Objective : The purpose of this study was to identify and compare the sex differences in episodic memory and spatial cognition in healthy young adults. Methods : Forty-eight undergraduates (male=24, female=24) were assessed for sex differences using the visual stimuli episodic memory task and the virtual reality-based spatial cognition task. The accuracy rates (%) for the What, Where, and When conditions of the episodic memory task and the average distance error (cm) for 10 trials of the spatial cognition task were analyzed. Results : There were no significant sex differences between the three conditions. The male participants showed a significantly higher performance on the spatial cognition task than the female participants Conclusion : The results of this study indicated that the sex differences in episodic memory could be altered by the test methods. Although episodic memory and spatial cognition mainly depend on the hippocampus, the sex-related differences between the two functions were inconsistent, suggesting that these two functions are independent.

Dense-Depth Map Estimation with LiDAR Depth Map and Optical Images based on Self-Organizing Map (라이다 깊이 맵과 이미지를 사용한 자기 조직화 지도 기반의 고밀도 깊이 맵 생성 방법)

  • Choi, Hansol;Lee, Jongseok;Sim, Donggyu
    • Journal of Broadcast Engineering
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    • v.26 no.3
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    • pp.283-295
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    • 2021
  • This paper proposes a method for generating dense depth map using information of color images and depth map generated based on lidar based on self-organizing map. The proposed depth map upsampling method consists of an initial depth prediction step for an area that has not been acquired from LiDAR and an initial depth filtering step. In the initial depth prediction step, stereo matching is performed on two color images to predict an initial depth value. In the depth map filtering step, in order to reduce the error of the predicted initial depth value, a self-organizing map technique is performed on the predicted depth pixel by using the measured depth pixel around the predicted depth pixel. In the process of self-organization map, a weight is determined according to a difference between a distance between a predicted depth pixel and an measured depth pixel and a color value corresponding to each pixel. In this paper, we compared the proposed method with the bilateral filter and k-nearest neighbor widely used as a depth map upsampling method for performance comparison. Compared to the bilateral filter and the k-nearest neighbor, the proposed method reduced by about 6.4% and 8.6% in terms of MAE, and about 10.8% and 14.3% in terms of RMSE.

A Study on Degradation Phenomenon Based on Test Device for Aging Diagnosis in PV Modules (태양광모듈의 열화진단 시험장치 구현 및 열화특성에 관한 연구)

  • Shen, Jian;Lee, Hu-Dong;Tae, Dong-Hyun;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.6
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    • pp.27-35
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    • 2021
  • Generally, a proper evaluation method of the aging phenomenon of PV modules is required as the electrical performance and lifespan of PV modules can degrade significantly due to several environmental factors, while they are generally known as devices that are used semi-permanently for more than 20 years. On the other hand, there is a lack of objectivity in the existing evaluation method of the aging phenomenon, which compares the adjusted PV output based on STC with the initial PV module specifications due to the data distortion while adjusting the measured data. Therefore, this study implemented a test device for an aging diagnosis to measure and collect actual data from a PV module section and modeled the data for aging using MATLAB S/W to minimize the variability of the PV output, communication error, and delay. Furthermore, this study confirmed the usefulness of the presented test device for aging diagnosis of the PV modules by diagnosing the total period and yearly-basis degradation rate of aging PV modules as 25.73% and 1.55%, respectively, according to the on-site output characteristics of the PV modules by season.