• Title/Summary/Keyword: Model Improvement

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A Mixed-effects Height-Diameter Model for Pinus densiflora Trees in Gangwon Province, Korea

  • Lee, Young Jin;Coble, Dean W.;Pyo, Jung Kee;Kim, Sung Ho;Lee, Woo Kyun;Choi, Jung Kee
    • Journal of Korean Society of Forest Science
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    • v.98 no.2
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    • pp.178-182
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    • 2009
  • A new mixed-effects model was developed that predicts individual-tree total height for Pinus densiflora trees in Gangwon province as a function of individual-tree diameter (cm). The mixed-effects model contains two random-effects parameters. Maximum likelihood estimation was used to fit the model to 560 height-diameter observations of individual trees measured throughout Gwangwon province in 2007 as part of the National Forest Inventory Program in Korea. The new model is an improvement over fixed-effects models because it can be calibrated to a local area, such as an inventory plot or individual stand. The new model also appears to be an improvement over the Forest Resources Evaluation and Prediction Program for the ten calibration trees used in this study. An example is provided that describes how to estimate the random-effects parameters using ten calibration trees.

Development and Application of a Water Quality Model to Assess Water Purification Techniques for Lakes and Reservoirs (호소수질정화공법의 평가를 위한 수질모형의 개발 및 적용)

  • 박병흔;권순국;장정렬
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.43 no.6
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    • pp.174-186
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    • 2001
  • Excessive outflow of pollutant loads resulting from rapid industrialization has unbalanced the water ecosystem, deteriorating the water quality environment severely. Therefore, measures for improving the water quality are necessary to maintain clean reservoir water and restore water-friendly spaces. A water quality model which is capable of simulating daily reservoir water quality was developed. The model had been applied to Masan reservoir and Wanggung reservoir in Korea. The model appeared to be satisfactory in representing the trend of water quality variations by comparing measured and simulated results. The model had been also applied to assess water purification techniques such as dredged pool, floating island and vegetation purification system. The model was considered to assess the effect of water purification techniques on reservoir water quality improvement. The results of water quality simulation for lake water purification techniques showed that a large facility would be needed to meet the targeted water quality of the reservoir when only one technique is applied. To effectively improve the quality of the polluted reservoir water, it is therefore recommended that pollutant sources should first be controlled, and a combination of the water purification techniques applied to make the utmost use of their secondary effects such as conservation of the reservoir volume capacity, establishment of a recreation space, promotion of bio-diversity, and improvement of the lake landscape.

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A Deep Learning Model for Extracting Consumer Sentiments using Recurrent Neural Network Techniques

  • Ranjan, Roop;Daniel, AK
    • International Journal of Computer Science & Network Security
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    • v.21 no.8
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    • pp.238-246
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    • 2021
  • The rapid rise of the Internet and social media has resulted in a large number of text-based reviews being placed on sites such as social media. In the age of social media, utilizing machine learning technologies to analyze the emotional context of comments aids in the understanding of QoS for any product or service. The classification and analysis of user reviews aids in the improvement of QoS. (Quality of Services). Machine Learning algorithms have evolved into a powerful tool for analyzing user sentiment. Unlike traditional categorization models, which are based on a set of rules. In sentiment categorization, Bidirectional Long Short-Term Memory (BiLSTM) has shown significant results, and Convolution Neural Network (CNN) has shown promising results. Using convolutions and pooling layers, CNN can successfully extract local information. BiLSTM uses dual LSTM orientations to increase the amount of background knowledge available to deep learning models. The suggested hybrid model combines the benefits of these two deep learning-based algorithms. The data source for analysis and classification was user reviews of Indian Railway Services on Twitter. The suggested hybrid model uses the Keras Embedding technique as an input source. The suggested model takes in data and generates lower-dimensional characteristics that result in a categorization result. The suggested hybrid model's performance was compared using Keras and Word2Vec, and the proposed model showed a significant improvement in response with an accuracy of 95.19 percent.

A Study on the Application of SCOR model for Integrated Defense Logistics System (군 통합물류체계 구축을 위한 SCOR모델 도입방안 연구)

  • Kim, Jeong-Hyeok;Choi, Seok-Cheol
    • Journal of the military operations research society of Korea
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    • v.31 no.1
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    • pp.73-92
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    • 2005
  • The SCOR(supply chain operations reference) model which is a management tool, has been developed to describe the business activities associated with all phases of satisfying a customer's demand. The model is able to successfully describe and provide a basis for supply chain improvement. In this paper, we review the SCOR model, the present status of the Korean defense logistics system, and suggest an application of the model for the integrated defense logistics system.

A HIGH-ORDER MODEL FOR SPIKE AND BUBBLE IN IMPULSIVELY ACCELERATED INTERFACE

  • Sohn, Sung-Ik
    • Korean Journal of Mathematics
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    • v.20 no.3
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    • pp.323-331
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    • 2012
  • We present a high-order potential ow model for the motion of the impulsively accelerated unstable interface of infinite density jump. The Layzer model for the evolution of the interface is extended to high-order. The time-evolution solutions of the bubble and the spike in the interface are obtained from the high-order model. We show that the high-order model gives improvement on the prediction of the evolution of the bubble and the spike.

An Action Research to Improve Fundamental Nursing Practice Course: Designing College Courses Model (수업디자인 모형을 적용한 기본간호학실습 수업 개선의 실행연구)

  • Kim, Heeyoung;Kim, Yun-Hee
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.22 no.2
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    • pp.169-179
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    • 2015
  • Purpose: The purpose of this study was to improve the quality of fundamental nursing practice course. Methods: Participants were 132 students who took the fundamental nursing practice course at D university in N city. The study included processes of planning, action, observation, and reflection. Quantitative data were analyzed using SPSS 20.0 program and qualitative data were evaluated through content analysis. Results: The 12-step designing college courses model by Fink was applied in the planning. In the acting stage, the course was conducted according to the instruction in designing the course, students wrote reflective journals and the professor gave feedback to the reflective journal and the class observation journal was used for lessons. In the observation stage, the course evaluation was surveyed and analyzed, evaluations were positive with 47.1% of students positively evaluating the teaching strategy. In the reflecting stage, outcomes in course improvement were reflected on and, the number of students at the lower level-of-achievement decreased. Conclusion: Action research was a useful research method that could capture the quality improvement process in college courses. Expression of effort and passion to improve quality of education through action research in various ways and to share quality improvement strategies for nursing education are important.

Square footing on geocell reinforced cohesionless soils

  • Biswas, Sefali;Mittal, Satyendra
    • Geomechanics and Engineering
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    • v.13 no.4
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    • pp.641-651
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    • 2017
  • Ground improvement with use of geosynthetic products is globally accepted now. The present paper discusses the improvement in bearing capacity of square footing placed at surface of cohesionless soil reinforced with geocell. Mohr-Coulomb failure criterion has been used in the observations. To study effects of geocell with respect to planar geogrid, model tests were conducted on planar reinforcement also. A comparative study of unreinforced soil and soil reinforced with plane geogrid and geocell has also been made. Numerical analysis results obtained by PLaxis have been compared with those obtained from model tests and were found to be in good agreement. A parametric study revealed the role of length of reinforcement, spacing between layers, placement of reinforcement from top surface etc. on bearing capacity. A design example given in paper illustrates the savings in cost of construction of footing on reinforced sand. The study shows that there is improvement in bearing capacity with respect to unreinforced soil which is of the order of 86%. Similarly settlement reduction is 13.07% for single layer of geocell which for double layers of geocell is 693% and 86.48% respectively. The cost reduction in case of reinforced soil is 35% as compared to unreinforced soil.

System Improvement Strategy by User Satisfaction Index Model Development and Measurement of Information System (정보시스템 이용자 만족지수 모델 개발 및 측정을 통한 시스템 개선방안)

  • Park, Yong-Jae;Lee, Sang-Hwan;Kwak, Seung-Jin
    • Journal of the Korean Society for information Management
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    • v.24 no.4
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    • pp.173-189
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    • 2007
  • By measuring satisfaction index of the users of Information System, it is possible not only to estimate ROI(Return on Investment) but also to draw the device for the efficiency and improvement of the System. This study tries to give User Satisfaction Index Model for the System, and present operators and managers of the system with the method for improving satisfaction and efficiency by measuring the User Satisfaction Index of representative information systems. For this, the survey was carried out for the representative information systems. On the basis of the analysis, Satisfaction Index was drawn and through Matrix Analysis, the strategy for system improvement was derived.

Analysis of Water-quality Improvement Efficiency of Constructed Wetland Using NPS-WET Model (NPS-WET 모형을 이용한 인공습지의 수질정화효과 분석)

  • Rhee, Han-Pil;Jung, Kwang-Wook;Lee, Bok-Soo;Ham, Jong-Hwa;Son, Yeong-Kwon
    • Journal of Korean Society on Water Environment
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    • v.28 no.2
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    • pp.320-331
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    • 2012
  • A combination system of catch canal and constructed wetland was designed and suggested to improve water quality in gagricultural region of lower Dong-jin river basin. In order to evaluate an water quality improvement efficiency of the designed combination system, the NPS-WET model was applied in this study. Simulation result of the NPS-WET shown that the nutrient load removal rate of constructed wetland was BOD, T-N, T-P and SS was 30.7~39.0%, 46~60%, 40.7~57.0% and 68.2~74.7%, respectively. Nutrients reduction of constructed wetland was higher in growing season than winter season because vital activity of microorganism, macrophyte and algae was augmented with high air and water temperature. Effluents from constructed wetland can affect water-quality of catch canal drains, especially, water-quality on junction point to Dong-jin river. Water-quality improvement in low-flowed catch canal (Un-san) was more significant than in high-flowed catch canal (Won-pyeong). In conclusion, a feasible design of constructed wetland is necessary to treat large quantity of receiving water. The NPS-WET is useful tool for assessing water-quality improvement efficiency using constructed wetland.

The Effects of Science Process Skin and Academic Achievement by the freedom Inquiry Using IIM (독자적 탐구방법(IIM)을 활용한 자유탐구가 과학탐구능력 및 학업성취도에 미치는 효과)

  • Lee, Yong-Seob;Hong, Soon-Won
    • Journal of the Korean Society of Earth Science Education
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    • v.2 no.1
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    • pp.33-40
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    • 2009
  • The purpose of this study is to examine the effect of higher grades in elementary the science process skill and Academic Achievement by IIM. To verify research problem, the subject of this study were five-grade students selected from One classes of an elementary school located in Ulsan : the experimental group is composed of thirty-four students who were participated in IIM teaching model situation. During six weeks, the IIM learning-based instruction was executed in th experimental group. Post-test showed following results: First, the experimental group showed a significant improvement in the science process skill. We look into detailly this, the experimental group showed a significant improvement in the basis science process skill. In particular, The sub-factor 'Observation', 'Measurement', 'expectation' of the science process skill effects a significant improvement. Second, the experimental group did showed a significant improvement in the Academic Achievement. In conclusion, IIM teaching model was more effective on science process skill and Academic Achievement. However, since the study has a limit on an objet of the study and the applied curriculum, the additional studies need to be conducted with an extended comparative group and curriculum.

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