• Title/Summary/Keyword: four classes

Search Result 964, Processing Time 0.026 seconds

A Short-Term Longitudinal Investigation of Pre- and Postnatal Depressive Symptoms of Korean Women (산전후 우울 변화 - 성장혼합모형을 이용한 단기종단연구)

  • Shin, Na-Ry
    • Journal of the Korean Home Economics Association
    • /
    • v.49 no.9
    • /
    • pp.59-72
    • /
    • 2011
  • This study examined whether there are underlying latent classes of growth trajectories of maternal depression in the Korean population. Data from the first phase of the Panel Study of Korean Children (PSKC) of the Institute of Child Care and Education (KICCE) were used for this study. The final sample of participants included 1,471 mothers, who completed three interviews: at birth, at one month, and at four months. A two-class model consisting of depression (12.3%) and non-depression (87.7%) was considered the best-fitting solution using Mplus 3.13. The changes in postnatal depression in the Korean population within four weeks after childbirth, which is the period of "postpartum onset", seem to be important. Logistic regression analysis showed that duration of breast-feeding and planned pregnancy effects were significantly associated with trajectory class membership.

On Some Spaces Isomorphic to the Space of Absolutely q-summable Double Sequences

  • Capan, Husamettin;Basar, Feyzi
    • Kyungpook Mathematical Journal
    • /
    • v.58 no.2
    • /
    • pp.271-289
    • /
    • 2018
  • Let 0 < q < ${\infty}$. In this study, we introduce the spaces ${\mathcal{BV}}_q$ and ${\mathcal{LS}}_q$ of q-bounded variation double sequences and q-summable double series as the domain of four-dimensional backward difference matrix ${\Delta}$ and summation matrix S in the space ${\mathcal{L}}_q$ of absolutely q-summable double sequences, respectively. Also, we determine their ${\alpha}$- and ${\beta}-duals$ and give the characterizations of some classes of four-dimensional matrix transformations in the case 0 < q ${\leq}$ 1.

: I. An Analysis on Striped Field Mice, Apodemus agrarius coreae Thomas, from Cheongju

  • Koh, Hung-Sun
    • The Korean Journal of Zoology
    • /
    • v.26 no.2
    • /
    • pp.123-134
    • /
    • 1983
  • Age variation and secondary sexual dimorphism in four external and 27 cranial characters of 102 specimens of striped firld mice, Apodemus agrarius coreae Thomas, from Cheongju, Korea, were analyzed statistically. Specimens were classified as subadults, young adults, middle-aged adults, and old adults, and variation of morphometric characters among the four age classes was evident. Significant secondary sexual dimorphism among sexes of the same age class was not revealed. Teh specimens of the same age class have to be used in further analyses to clarify geographic variation of morphometric characters in Apodemus agrarius from Korea.

  • PDF

Fish fauna and the population of a Korean endangered freshwater fish, Brachymystax lenok tsinlingensis, in Korea: Bonghwa Habitat

  • Lim, Dohun;Lee, Yoonjin
    • Environmental Engineering Research
    • /
    • v.24 no.4
    • /
    • pp.638-645
    • /
    • 2019
  • This research was an evaluation of the fish fauna and the habitat for Brachymystax lenok tsinlingensis (B. lenok tsinlingensis) for 11 stations at the Bonghwa-gun sanctuary. The predominant species in this research area was Zacco koreanus. B. lenok tsinlingensis, which has been designated as an endangered freshwater fish in Korea, was found in the Bonghwa sanctuary zone, except at stations 5 and 6. The B. lenok individuals were shorter in length than 400 mm. In total, 13 endemic species were found, including Coreoleuciscus splendidus and Iksookimia longicorpus. Specimens of Koreocobitis naktongensis, a first grade endangered species, were also collected. The benthic macroinvertebrates consisted of four divisions, four classes, seven orders, 30 families, 60 species, and 10,344 individuals and were distributed among the orders Ephemeroptera (55.9%), Diptera (18.2%), Trichoptera (12.4%), Plecoptera (2.1%), and Odonata (0.3%).

Development of Problem-Based Learning in an English-Mediated College Science Course: Design-Based Research on Four Semesters Instruction

  • LAHAYE, Rob;LEE, Sang-eun
    • Educational Technology International
    • /
    • v.19 no.2
    • /
    • pp.229-254
    • /
    • 2018
  • Universities in Korea have driven universities' new attempts to adopt more learner-centered and active learning in English. Problem-based Learning (PBL) is one of the well-known constructive teaching and learning methodologies in higher education. Our research goal was to design and develop the optimal PBL practices for a college physics course taught in English to promote learning and course satisfaction. For four semesters, we have tried and adjusted PBL components, and looked at the trend of the exam scores and group work achievement in each semester. We found that the number of problems and the duration of problem solving are the critical factors that influence the effect of PBL in a college physics course taught in English by going through iterative implementation. The iterative process of applying, designing, and constructing PBL to physics classes was meaningful not only in that we have found the optimal PBL model for learning a college physics course, but also in that we have been reflecting on the continuous interaction with learners during the course.

Multiple renal veins clogging the hilum of the right kidney

  • Satheesha B Nayak;Narendra Pamidi;Vasanthakumar Packirisamy;Soumya Kodimajalu Vasudeva
    • Anatomy and Cell Biology
    • /
    • v.56 no.1
    • /
    • pp.141-144
    • /
    • 2023
  • Knowledge of variations of renal vessels is of utmost importance in retroperitoneal surgeries and kidney transplant surgeries. We report concurrent variations of the right renal vessels, observed in an adult male cadaver during dissection classes. The right kidney was supplied by three renal arteries, out of which two entered the kidney through the hilum and the other one entered through the lower pole of the kidney. There were five renal veins, emerging independently from the hilum and opening separately through five openings into the inferior vena cava. Among the veins, only one emerged anterior to the renal pelvis and the other four emerged behind it. Four of them terminated into the posterolateral aspect of the inferior vena cava, whereas one terminated into its anterior aspect. Fourth vein from above, received the right testicular vein. The renal hilum was clogged with the presence of seven vessels and renal pelvis.

Major Class Recommendation System based on Deep learning using Network Analysis (네트워크 분석을 활용한 딥러닝 기반 전공과목 추천 시스템)

  • Lee, Jae Kyu;Park, Heesung;Kim, Wooju
    • Journal of Intelligence and Information Systems
    • /
    • v.27 no.3
    • /
    • pp.95-112
    • /
    • 2021
  • In university education, the choice of major class plays an important role in students' careers. However, in line with the changes in the industry, the fields of major subjects by department are diversifying and increasing in number in university education. As a result, students have difficulty to choose and take classes according to their career paths. In general, students choose classes based on experiences such as choices of peers or advice from seniors. This has the advantage of being able to take into account the general situation, but it does not reflect individual tendencies and considerations of existing courses, and has a problem that leads to information inequality that is shared only among specific students. In addition, as non-face-to-face classes have recently been conducted and exchanges between students have decreased, even experience-based decisions have not been made as well. Therefore, this study proposes a recommendation system model that can recommend college major classes suitable for individual characteristics based on data rather than experience. The recommendation system recommends information and content (music, movies, books, images, etc.) that a specific user may be interested in. It is already widely used in services where it is important to consider individual tendencies such as YouTube and Facebook, and you can experience it familiarly in providing personalized services in content services such as over-the-top media services (OTT). Classes are also a kind of content consumption in terms of selecting classes suitable for individuals from a set content list. However, unlike other content consumption, it is characterized by a large influence of selection results. For example, in the case of music and movies, it is usually consumed once and the time required to consume content is short. Therefore, the importance of each item is relatively low, and there is no deep concern in selecting. Major classes usually have a long consumption time because they have to be taken for one semester, and each item has a high importance and requires greater caution in choice because it affects many things such as career and graduation requirements depending on the composition of the selected classes. Depending on the unique characteristics of these major classes, the recommendation system in the education field supports decision-making that reflects individual characteristics that are meaningful and cannot be reflected in experience-based decision-making, even though it has a relatively small number of item ranges. This study aims to realize personalized education and enhance students' educational satisfaction by presenting a recommendation model for university major class. In the model study, class history data of undergraduate students at University from 2015 to 2017 were used, and students and their major names were used as metadata. The class history data is implicit feedback data that only indicates whether content is consumed, not reflecting preferences for classes. Therefore, when we derive embedding vectors that characterize students and classes, their expressive power is low. With these issues in mind, this study proposes a Net-NeuMF model that generates vectors of students, classes through network analysis and utilizes them as input values of the model. The model was based on the structure of NeuMF using one-hot vectors, a representative model using data with implicit feedback. The input vectors of the model are generated to represent the characteristic of students and classes through network analysis. To generate a vector representing a student, each student is set to a node and the edge is designed to connect with a weight if the two students take the same class. Similarly, to generate a vector representing the class, each class was set as a node, and the edge connected if any students had taken the classes in common. Thus, we utilize Node2Vec, a representation learning methodology that quantifies the characteristics of each node. For the evaluation of the model, we used four indicators that are mainly utilized by recommendation systems, and experiments were conducted on three different dimensions to analyze the impact of embedding dimensions on the model. The results show better performance on evaluation metrics regardless of dimension than when using one-hot vectors in existing NeuMF structures. Thus, this work contributes to a network of students (users) and classes (items) to increase expressiveness over existing one-hot embeddings, to match the characteristics of each structure that constitutes the model, and to show better performance on various kinds of evaluation metrics compared to existing methodologies.

Classification of Daily Precipitation Patterns in South Korea using Mutivariate Statistical Methods

  • Mika, Janos;Kim, Baek-Jo;Park, Jong-Kil
    • Journal of Environmental Science International
    • /
    • v.15 no.12
    • /
    • pp.1125-1139
    • /
    • 2006
  • The cluster analysis of diurnal precipitation patterns is performed by using daily precipitation of 59 stations in South Korea from 1973 to 1996 in four seasons of each year. Four seasons are shifted forward by 15 days compared to the general ones. Number of clusters are 15 in winter, 16 in spring and autumn, and 26 in summer, respectively. One of the classes is the totally dry day in each season, indicating that precipitation is never observed at any station. This is treated separately in this study. Distribution of the days among the clusters is rather uneven with rather low area-mean precipitation occurring most frequently. These 4 (seasons)$\times$2 (wet and dry days) classes represent more than the half (59 %) of all days of the year. On the other hand, even the smallest seasonal clusters show at least $5\sim9$ members in the 24 years (1973-1996) period of classification. The cluster analysis is directly performed for the major $5\sim8$ non-correlated coefficients of the diurnal precipitation patterns obtained by factor analysis In order to consider the spatial correlation. More specifically, hierarchical clustering based on Euclidean distance and Ward's method of agglomeration is applied. The relative variance explained by the clustering is as high as average (63%) with better capability in spring (66%) and winter (69 %), but lower than average in autumn (60%) and summer (59%). Through applying weighted relative variances, i.e. dividing the squared deviations by the cluster averages, we obtain even better values, i.e 78 % in average, compared to the same index without clustering. This means that the highest variance remains in the clusters with more precipitation. Besides all statistics necessary for the validation of the final classification, 4 cluster centers are mapped for each season to illustrate the range of typical extremities, paired according to their area mean precipitation or negative pattern correlation. Possible alternatives of the performed classification and reasons for their rejection are also discussed with inclusion of a wide spectrum of recommended applications.

Elementary School Students' Images of Science Class and Factors Influencing Their Formations (초등학생들의 과학 수업에 대한 이미지와 이미지 형성에 영향을 미치는 요인)

  • Kang, Hun-Sik;Lee, Ji-Young
    • Journal of The Korean Association For Science Education
    • /
    • v.30 no.4
    • /
    • pp.519-531
    • /
    • 2010
  • In this study, we investigated the elementary school students' images of science class and the factors influencing their formations. 280 sixth graders were selected from nine elementary schools in Gyeonggi province and Gangwon province and the DASCT-C (Draw-A-Science-Class-Test Checklist) was administered. In addition, four students were individually interviewed in order to investigate their responses deeply. Analyses of the results revealed that the students' images of science class for four science subjects (physics, chemistry, biology, and earth science) were more 'student-centered' than 'teacher-centered' or 'neutral'. The students of the teacher with student-centered image of science class had also more student-centered images than those with teacher-centered images. Many students answered that the main factors affecting their images of science class were the experiences of impressed or funny science classes, the perceptions of wanted science classes, the active science learning experiences, the educational experiences outside the school curriculum, and the negative science learning experiences. Educational implications of these findings are discussed.

Analyzing College Students' Perception of Quality Computer Class (좋은 컴퓨터 수업에 대한 대학생들의 인식 유형 분석)

  • Kim, Dugyu;Lee, Jaemu
    • Journal of The Korean Association of Information Education
    • /
    • v.24 no.3
    • /
    • pp.225-232
    • /
    • 2020
  • This study is to clarify how college students think about quality computer classes. Q methodology is applied to extract the subjective thinking of college students. After extracting the statements through students' interviews and advanced study, the 54 Q samples were selected. The P sample consisted of 50 college students. They performed Q sort against the Q sample questionnaire. The Q sort results were analyzed by performing QUANL program. As a result of the analysis, four types of perceptions of quality computer classes based on college students' ideas were extracted. There were no differences between male and female students, but there was a clear difference between general college and teacher's college students by type. The types were divided into four categories which we named as follows: is 'Value change-oriented class through creative problem-solving', is 'Improving computer application skills through the learner's competition', is 'Improving advanced computer technology with programming skills' and is 'Learner centered pleasant class'.