• Title/Summary/Keyword: natural selection

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Decision of River Rehabilitation Plan using Multi-criteria Decision Making (다기준 의사결정을 활용한 자연형 하천 대안 선정)

  • Cho, Hong-Je;Hwang, Jae-Ho;Yoon, Jong-Chun
    • Journal of Wetlands Research
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    • v.12 no.2
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    • pp.87-93
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    • 2010
  • River restoration plan and selection method are needed to reflect the diversity of river. Meanwhile, the ultimate purpose of river restoration is natural recovery of the river. Recently. hydrophilic enhancement is a tendency to include. In this study, naturalness of a river was used to establish alternative for the natural river recovery. Also, naturalness of a river calculated by using the evaluation of river naturalness that was developed using multi-criteria decision making to fit the environmental conditions in Korea. After selection the evaluation items for assessing the naturalness of the river based on the characteristics of the river, multiple alternatives were constructed and the naturalness of river for each of those alternatives were estimated. Comparing the estimated values has made the measurement of the natural recovery effect for each alternative efficient.

Assessment of Pathogenic Variation against Pitch Canker Pathogen, Fusarium circinatum in Pinus thunbergii and Responses of Natural Selection Pinus × rigitaeda to Branch Inoculation in a Seed Orchard

  • Woo, Kwan-Soo;Yoon, Jun-Hyuck;Han, Sang-Urk;Kim, Chang-Soo
    • The Plant Pathology Journal
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    • v.26 no.4
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    • pp.299-305
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    • 2010
  • A half-sib family of two 4-year-old seedlings of Pinus $\times$ rigitaeda was inoculated with each of 20 Pinus thunbergii isolates of Fusarium circinatum (syn. Fusarium subglutinans f. sp. pini) from two pitch canker damaged sites in Jeju Island, South Korea. Initial symptoms of needle damages were visible on most of the seedlings at 18 days after inoculation. The 20 tested isolates were not significantly different in virulence, based on lesion lengths at the site of inoculation (P = 0.217). The most virulent isolate FT-7 showed the longest lesion length. Some seedlings began to die 46 days after inoculation. All seedlings were dead by 68 days after inoculation except two seedlings inoculated with each of isolates FS-2 and FS-13, respectively. Using the FT-7, 38-year-old 11 P. $\times$ rigitaeda trees, which were survived from a seed orchard severely damaged by pitch canker, were inoculated on branches in the seed orchard in Jeju Island to assess differences in susceptibility to pitch canker. The 11 trees differed significantly (P < 0.001) in susceptibility to F. circinatum based on average lesion lengths measured 56 days after inoculation. It is possible that induced resistance contributed to their capacity to limit lesion development. The susceptibility of natural selection P. $\times$ rigitaeda trees are more likely affected by interaction with F. circinatum rather than environmental conditions.

Resume Classification System using Natural Language Processing & Machine Learning Techniques

  • Irfan Ali;Nimra;Ghulam Mujtaba;Zahid Hussain Khand;Zafar Ali;Sajid Khan
    • International Journal of Computer Science & Network Security
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    • v.24 no.7
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    • pp.108-117
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    • 2024
  • The selection and recommendation of a suitable job applicant from the pool of thousands of applications are often daunting jobs for an employer. The recommendation and selection process significantly increases the workload of the concerned department of an employer. Thus, Resume Classification System using the Natural Language Processing (NLP) and Machine Learning (ML) techniques could automate this tedious process and ease the job of an employer. Moreover, the automation of this process can significantly expedite and transparent the applicants' selection process with mere human involvement. Nevertheless, various Machine Learning approaches have been proposed to develop Resume Classification Systems. However, this study presents an automated NLP and ML-based system that classifies the Resumes according to job categories with performance guarantees. This study employs various ML algorithms and NLP techniques to measure the accuracy of Resume Classification Systems and proposes a solution with better accuracy and reliability in different settings. To demonstrate the significance of NLP & ML techniques for processing & classification of Resumes, the extracted features were tested on nine machine learning models Support Vector Machine - SVM (Linear, SGD, SVC & NuSVC), Naïve Bayes (Bernoulli, Multinomial & Gaussian), K-Nearest Neighbor (KNN) and Logistic Regression (LR). The Term-Frequency Inverse Document (TF-IDF) feature representation scheme proven suitable for Resume Classification Task. The developed models were evaluated using F-ScoreM, RecallM, PrecissionM, and overall Accuracy. The experimental results indicate that using the One-Vs-Rest-Classification strategy for this multi-class Resume Classification task, the SVM class of Machine Learning algorithms performed better on the study dataset with over 96% overall accuracy. The promising results suggest that NLP & ML techniques employed in this study could be used for the Resume Classification task.

Analyzing the Effectiveness of Argumentation Program to Conceptualize the Concept of Natural Selection for Elementary Science-Gifted Students (초등과학영재들의 자연선택 개념 형성을 위한 논변활동 효과 분석)

  • Park, Chuljin;Cha, Heeyoung
    • Journal of The Korean Association For Science Education
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    • v.36 no.4
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    • pp.591-606
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    • 2016
  • The purpose of this study is to develop the argumentation program to build scientific concepts on natural selection for science-gifted elementary students and to know how to implement this program. For this study, nine key concepts about natural selection such as the overproduction of offspring, limited resources, population stability, competition, variation, heredity of variation, differential survival, change of the population and speciation were selected through the literature study. The programs were developed by learning cycle instructional model. Argument writings and discourses have been collected, analyzed and compared before and after the program. Two questionnaires to compare pre and post concept change consist of multiple choice questionnaire and open-ended response question were developed and applied to 19 science-gifted elementary students. Sufficiency of the explanation and conceptual quality of the explanation were used to assess the quality of their arguments before and after the program. Discourse and visual models collected from the highest and lowest group about score improvement were compared. The scores of the gifted statistically improved significantly in multiple choice questionnaire. Students' alternative conceptions about natural selection at the beginning of the program decreased and changed scientifically after the program. Visual models drawn by the students supported the results as well. This study asserts that elementary science-gifted students are able to explain evolutionary perspectives about organism change and use the key concepts of natural selection. The study means that evolutionary perspective is possible to be reflected in elementary science curriculum for the gifted.

Analysis of Epistemic Considerations and Scientific Argumentation Level in Argumentation to Conceptualize the Concept of Natural Selection of Science-Gifted Elementary Students (초등 과학 영재 학생들의 자연선택 개념 이해를 위한 논변 활동에서 나타난 인식적 이해와 논변활동 수준 분석)

  • Park, Chuljin;Cha, Heeyoung
    • Journal of The Korean Association For Science Education
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    • v.37 no.4
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    • pp.565-575
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    • 2017
  • This study analyzes the epistemic considerations and the argumentation level revealed in the discourse of the key concept of natural selection for science-gifted elementary students. The paper analyzes and discusses the results of a three-student focus group, drawn from a cohort of twenty gifted sixth-grade elementary students. Nature, generality, justification, and audience were used to analyze epistemic consideration. Learning progression in scientific argumentation including argument construction and critique was used to analyze students' scientific argumentation level. The findings are as follows: First, Epistemic considerations in discourse varied between key concepts of natural selection discussed. The nature aspect of epistemic considerations is highly expressed in the discourse for all natural selection key concepts. But the level of generality, justification and audience was high or low, and the level was not revealed in the discourse. In the heredity of variation, which is highly expressed in terms of generality of knowledge, the linkage with various phenomena against the acquired character generated a variety of ideas. These ideas were used to facilitate engagement in argumentation, so that all three students showed the level of argumentation of suggestions of counter-critique. Second, students tried to explain the process of speciation by using concepts that were high in practical epistemic considerations level when explaining the concept of speciation, which is the final natural selection key concept. Conversely, the concept of low level of epistemic considerations was not included as an explanation factor. The results of this study suggest that students need to analyze specific factors to understand why epistemological decisions are made by students and how epistemological resources are used according to context through various epistemological resources. Analysis of various factors influencing epistemological decisions can be a mediator of the instructor who can improve the quality and level of the argumentation.

Genetic Diversity and Natural Selection in 42 kDa Region of Plasmodium vivax Merozoite Surface Protein-1 from China-Myanmar Endemic Border

  • Zhou, Xia;Tambo, Ernest;Su, Jing;Fang, Qiang;Ruan, Wei;Chen, Jun-Hu;Yin, Ming-Bo;Zhou, Xiao-Nong
    • Parasites, Hosts and Diseases
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    • v.55 no.5
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    • pp.473-480
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    • 2017
  • Plasmodium vivax merozoite surface protein-1 (PvMSP1) gene codes for a major malaria vaccine candidate antigen. However, its polymorphic nature represents an obstacle to the design of a protective vaccine. In this study, we analyzed the genetic polymorphism and natural selection of the C-terminal 42 kDa fragment within PvMSP1 gene ($PvMSP1_{42}$) from 77 P. vivax isolates, collected from imported cases of China-Myanmar border (CMB) areas in Yunnan province and the inland cases from Anhui, Yunnan, and Zhejiang province in China during 2009-2012. Totally, 41 haplotypes were identified and 30 of them were new haplotypes. The differences between the rates of non-synonymous and synonymous mutations suggest that $PvMSP1_{42}$ has evolved under natural selection, and a high selective pressure preferentially acted on regions identified of $PvMSP1_{33}$. Our results also demonstrated that $PvMSP1_{42}$ of P. vivax isolates collected on China-Myanmar border areas display higher genetic polymorphisms than those collected from inland of China. Such results have significant implications for understanding the dynamic of the P. vivax population and may be useful information towards China malaria elimination campaign strategies.

The Effects of Activity-Centered Instruction on Understanding of Natural Selection Concept (자연선택개념의 이해를 위한 활동중심수업의 효과)

  • Park, Jong-Boon;Lee, Mi-Sook;Lee, Kil-Jae
    • Journal of The Korean Association For Science Education
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    • v.23 no.5
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    • pp.505-516
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    • 2003
  • The concept of evolution is one of the most important concepts in the learning biology. However lots of students have difficulties in understanding its mechanism because their preexisted alternative concepts interrupt in gaining the correct idea of evolution. Students usually have the Larmarkian or teleological ideas of evolution. The purpose of this study is to investigate the effectiveness of an activity-centered instruction on the learner's conceptual change from misconception into the scientific concept, Darwinian one, and achievement. For the study, 162 students were sampled from a high school: 81 students for the activity-centered instruction and 81 students for traditional instruction. The result is as follows; 1) The activity-centered instruction is more effective than the traditional one in understanding the concept of Darwinian natural selection(p<.05) and in changing the students' various misconceptions of evolution into Darwinian one. 2) The activity-centered instruction concerning natural selection is more effective in their achievement(p<.01). 3) However, after both of the instructions, some students still kept the Lamarkian thoughts.

Scoring Korean Written Responses Using English-Based Automated Computer Scoring Models and Machine Translation: A Case of Natural Selection Concept Test (영어기반 컴퓨터자동채점모델과 기계번역을 활용한 서술형 한국어 응답 채점 -자연선택개념평가 사례-)

  • Ha, Minsu
    • Journal of The Korean Association For Science Education
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    • v.36 no.3
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    • pp.389-397
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    • 2016
  • This study aims to test the efficacy of English-based automated computer scoring models and machine translation to score Korean college students' written responses on natural selection concept items. To this end, I collected 128 pre-service biology teachers' written responses on four-item instrument (total 512 written responses). The machine translation software (i.e., Google Translate) translated both original responses and spell-corrected responses. The presence/absence of five scientific ideas and three $na{\ddot{i}}ve$ ideas in both translated responses were judged by the automated computer scoring models (i.e., EvoGrader). The computer-scored results (4096 predictions) were compared with expert-scored results. The results illustrated that no significant differences in both average scores and statistical results using average scores was found between the computer-scored result and experts-scored result. The Pearson correlation coefficients of composite scores for each student between computer scoring and experts scoring were 0.848 for scientific ideas and 0.776 for $na{\ddot{i}}ve$ ideas. The inter-rater reliability indices (Cohen kappa) between computer scoring and experts scoring for linguistically simple concepts (e.g., variation, competition, and limited resources) were over 0.8. These findings reveal that the English-based automated computer scoring models and machine translation can be a promising method in scoring Korean college students' written responses on natural selection concept items.

Pre-service Biology Teachers' Perspectives about Biological Competition and Adaptation (생물학적 경쟁과 적응에 대한 예비 생물 교사의 인식)

  • Jo, Jiseon;Cha, Heeyoung;Yang, Pilseung
    • Journal of The Korean Association For Science Education
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    • v.36 no.5
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    • pp.801-814
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    • 2016
  • The purpose of this study is to find out whether pre-service biology teachers' biological meanings of competition and adaptation is the same as everyday meanings to understand natural selection and evolution. Fifty three pre-service biology teachers answered written tests and thirteen of them were interviewed. The tests on general meanings on competition and adaptation, tests on biological meanings on competition and adaptation and tests on natural selection were administered. Questions on semi-structured interviews were composed of only biological meanings about competition and adaptation. Analyzing data through four steps, pre-service biological teachers' general meanings on competition and adaptation were compared with the definitions of Korean dictionary and compared with biological definitions. Pre-service teachers' alternative conceptions about biological competition and adaptation were classified and the alternative conceptual types were checked when explaining natural selection and evolution. They realized competition is battle for intention or purpose like everyday meaning of competition. However, they didn't realize adaptation happen in the population level. They thought that adaptation, like in everyday life meaning, is getting suitable to environment for survival on an individual level. By relating adaptation to evolution, they thought that long-lasting adaptation become evolution. This study has significance with respect to suggesting the alternative concepts of competition and adaptation based on effective evolution teaching from constructivism viewpoint and highlighting the importance of the concepts of biological competition and adaptation, which have been concerned rarely for a long time.

Analysis of Pure Refrigerant Cycle Design on C3MR Process through Driver Selection (동력 공급 장치 선택을 통한 C3MR 공정의 순수냉매 사이클 설계 분석)

  • Lee, Inkyu;Tak, Kyungjae;Lim, Wonsub;Moon, Il;Kim, Haksung;Choi, Kwangho
    • Journal of the Korean Institute of Gas
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    • v.17 no.3
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    • pp.27-32
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    • 2013
  • Natural gas liquefaction process which is operated under cryogenic condition spends large amount of energy. Most of energy in the natural gas liquefaction process is consumed by compressors. Therefore, minimizing energy consumption of compressors is an important issue in process design and operation. Among various natural gas liquefaction processes, propane pre-cooled mixed refrigerant (C3MR) process consists of mixed refrigerant system and pure refrigerant system. In this study, to find the optimal design of pure refrigerant system, pure refrigerant cycle is simulated on different number of pressure levels and the necessary energy of each design is compared. After that, the driver selection model is applied to analyse each processes, which has different number of equipments, in terms of cost. As the result, the design using many equipments spends lower energy. Using this result, this study suggests standard of process design selection by the cost term.