• Title/Summary/Keyword: small group processes

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A Study of Teaching and Learning Strategies for a Creative Sight-singing and Ear-trainig Program (창의적인 시창·청음 프로그램을 위한 교수·학습 전략 연구)

  • Park, Young Joo
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.3
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    • pp.359-365
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    • 2022
  • This study was to provide teaching and learning strategies to develop a creative sight-singing and ear-training program that aims to design student-centered education. Therefore, the characteristics of the sight-singing and ear-training as well as teaching and learning methods were analyzed through the literature review, and the following meaningful strategies were derived. First, a student-centered teaching environment was promoted by diversifying the teaching environment through small group activities and establishing a sustainable learning environment using MyEarTraining and Musescore applications. Second, teaching and learning strategies were proposed to improve sight-singing and ear-training skills by applying for various teaching and learning methods and cultivating the qualities of a pre-service teacher. This study is expected to be used as meaningful fundamental data in developing specific teaching and learning processes for a creative sight-singing and ear-training program.

A Study on the Strategic Trade Policy of Korea, China and Japan in the Era of Digital Trade (디지털무역 시대의 한국·중국·일본의 전략적 무역정책에 관한 연구)

  • Jia-Jia Liu;Nak-Hyun Han
    • Korea Trade Review
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    • v.47 no.6
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    • pp.335-353
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    • 2022
  • There are two aspects of digital trade: the digitalisation of goods/services being traded and the digitalisation of the transactional act. Digital data (i.e. machine-readable industrial data and transactional data) is the major driving force for both aspects of digital trade. Digital data is a non-rivalrous input, whether for production or marketing activities, and is thus able to be used by many firms or government agencies without limiting the use of others. Digital platforms provide online infrastructure for the interactions between groups, for instance, consumers and producers. The externality effect refers to the situation in which prosperity in one group on a given platform will improve the returns of other groups on the same platform. In the era of the data-driven economy, strategic trade policy can involve data-related policies. The major objective of these policies is to improve the competitiveness of domestic firms. For instance, firms may be subsidised if they use cloud services provided by specific platforms. This strand of strategic trade policies might be useful for increasing the competitiveness of small-and medium-sized enterprises (SMEs) via the digitalisation of production/marketing processes. Alternatively, strategic trade policy may also exploit the externality effect via platform economy-related policies. Further, some countries may form data coalitions to facilitate cross-border data flow. This paper uses cases in Asian countries to illustrate which role these strategic trade policies can play in the digital economy.

Middle School Students' Construction of Physics Inquiry Problems and Variables Isolation and Clarification during Small Group Open-inquiry Activities (중학생의 소집단 자유탐구활동 중 물리 영역 탐구문제의 구성과 변인 추출 및 명료화 과정)

  • Yoo, Junehee;Kim, Jongsook
    • Journal of The Korean Association For Science Education
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    • v.32 no.5
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    • pp.903-927
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    • 2012
  • The study aimed to analyze middle school students construction of physics inquiry problems for open inquiry from the viewpoint of variable isolation and clarification, and investigate students' difficulties during the processes of variable isolation and clarification to get implications for teaching and learning strategies for small group open inquiry activities which have been included in the 2007 national curriculum. The participants were 4 students who had attended an outreach program for the science gifted run by a university institution located in Seoul area. They performed an open inquiry on egg drop for 13 lessons for 30 hours. Level descriptions for variable isolation and clarification have been developed and applied to analyze students' inquiry problems and variables included by the problems. Students iterated inquiry processed 5 times and the inquiry problem showed progress gradually. Dependent variables have been isolated ahead and the levels of variable isolation and clarification showed higher than the independent variables. Many kinds of independent variables isolated extensively and the independent variables and control variables have been mingled. One of the reasons why students had some difficulties in isolation of independent variables could be the absence of theoretical models. The realities of school lab could restrict the variable isolation and clarification as well as topic selections. Some sensory or extensive variables such as broken eggs and drop height seem to be salient to be focused on as core variables. Lack of background knowledges could be one of the reasons for students' difficulties in variable clarification, such as theoretical definitions and operational definitions. As a result of lacking background knowledges, students could not construct theoretical models even though they could isolate and clarify variables as scientific lexical definitions. Some perceptions of inquiry as trial and error or reckless establishment of causal relations between variables could be accounted as one reason.

Collective Understanding through Social Mediational Processes in a Collaborative Workshop between Science Teachers and Researchers: Focusing on 'Conflict' Aspect (과학 교사-연구자간 협력적 워크숍에서 사회적 중재를 통한 집합적 이해 과정: '갈등' 양상을 중심으로)

  • Kim, Hyeree;Lee, Sun-Kyung;Kim, Chan-Jong
    • Journal of The Korean Association For Science Education
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    • v.32 no.10
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    • pp.1502-1523
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    • 2012
  • Recently, there have been growing interest in teachers' professional development since teachers were regarded as a critical factor in the context of the reform efforts. Along with these efforts, educational researchers have continued to implement various programs to improve teachers' subject matter knowledge, beliefs, and their practices. Although considerable researches have been done regarding the efficiency of these programs, most of them have focused on individual teacher's change. However, a "teacher's mind is socially formed" (Edwards, 2001). This perspective indicates that teacher change is necessarily viewed in terms of social mediational process between individual and the social context. This study examines the interactions between teachers and researchers in order to explore the mediational processes and the aspects of collective understanding, which has emerged from the collaborative workshop. The data were collected from small group activities in a workshop and then analyzed using interactional sociolinguistic approach. Futhermore, activity system was employed to describe the social mediational process. The findings show that participating teachers constructed knowledge through conflict regarding collective understanding. This process of collective understanding was mediated by object, rules, and roles within each activity system. Findings from the study suggest that the sociocultural perspectives to teacher education are essential in understanding how teachers learn to teach and that teachers' professional discourse can play a significant role in teachers' professional development.

A Study on Space Design and Space Uses of Community Based Small Public Libraries - Focused on the Cases of Ann Arbor District Library in the United States - (소규모 지역 공공도서관의 공간 구성과 이용 특성 연구 - 미국 앤아버 공공도서관 브랜치의 사례조사를 중심으로 -)

  • Moon, Eun-Mi
    • Korean Institute of Interior Design Journal
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    • v.19 no.5
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    • pp.217-225
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    • 2010
  • Today's public libraries in communities are on the processes of changes to integrate information and communication technology into traditional library system in order to support current users' demands for the new digital era. The purpose of this study is to examine the changing characters on space design and space uses of community based public libraries by conducting case studies of three branch libraries which were built after 2004 in Ann Arbor, Michigan in the United States. As the conclusion of this research, the findings of the case studies are utilized as basic data for planning and design guidelines for public libraries as community resources. The study summarizes the characteristics of space design and space uses in public libraries as follow; first, the floor plans of small-scale public libraries are open visually as well as spatially. The space organization of the libraries is arranged by potential noise levels, as placing noisy spaces near the entrance halls and quiet spaces at the back. Main book shelves are located in the middle of the library buildings, while seats are arranged along the window sides. By placing various kinds of furniture in open reading areas, library users can select different types of seats and tables for their comforts. Second. the survey of observation also finds that a large number of users often use library computers and personal computers to connect the internet at the libraries. These personal computer users who are new user group in community based libraries preferred to sit in casual study areas and individual tables with one or two seats only. Third, the libraries, in addition, develop and provide various programs and events for people in communities. Especially, the programs for children, the elderly and new comers from the abroad are well prepared, thus provide opportunities for them to visit the libraries in regular bases. The survey finds that family entertainment and leisure activities are the important parts of the program as well as renting music CD and movie DVD are also important reasons for people to come. Thus, the libraries prepare high quality children's space and CD shelves near the entrance hall.

The Impact of Human Resource Innovativeness, Learning Orientation, and Their Interaction on Innovation Effect and Business Performance : Comparison of Small and Medium-Sized vs. Large-Sized Companies (인적자원의 혁신성, 학습지향성, 이들의 상호작용이 혁신효과 및 사업성과에 미치는 영향 : 중소기업과 대기업의 비교연구)

  • Yoh, Eunah
    • Korean small business review
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    • v.31 no.2
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    • pp.19-37
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    • 2009
  • The purpose of this research is to explore differences between small and medium-sized companies and large-sized companies in the impact of human resource innovativeness(HRI), learning orientation(LO), and HRI-LO interaction on innovation effect and business performance. Although learning orientation has long been considered as a key factor influencing good performance of a business, little research was devoted to exploring the effect of HRI-LO interaction on innovation effect and business performance. In this study, it is investigated whether there is a synergy effect between innovative human workforce and learning orientation corporate culture, in addition to each by itself, to generate good business performance as well as a success of new innovations in the market. Research hypotheses were as follows, including H1) human resource innovativeness(HRI), learning orientation(LO), and interactions of HRI and LO(HRI-LO interaction) positively affect innovation effect, H2) there is a difference of the effect of HRI, LO, and HRI-LO interaction on innovation effect between large-sized and small-sized companies, H3) HRI, LO, HRI-LO interaction, innovation effect positively affect business performance, and H4) there is a difference of the effect of HRI, LO, HRI-LO interaction, and innovation effect on business performance between large-sized and small-sized companies. Data were obtained from 479 practitioners through a web survey since the web survey is an efficient method to collect a national data at a variety of fields. A single respondent from a company was allowed to participate in the study after checking whether they have more than 5-year work experiences in the company. To check whether a common source bias is existed in the sample, additional data from a convenient sample of 97 companies were gathered through the traditional survey method, and were used to confirm correlations between research variables of the original sample and the additional sample. Data were divided into two groups according to company size, such as 352 small and medium-sized companies with less than 300 employees and 127 large-sized companies with 300 or more employees. Data were analyzed through t-test and regression analyses. HRI which is the innovativeness of human resources in the company was measured with 9 items assessing the innovativenss of practitioners in staff, manager, and executive-level positions. LO is the company's effort to encourage employees' development, sharing, and utilizing of knowledge through consistent learning. LO was measured by 18 items assessing commitment to learning, vision sharing, and open-mindedness. Innovation effect which assesses a success of new products/services in the market, was measured with 3 items. Business performance was measured by respondents' evaluations on profitability, sales increase, market share, and general business performance, compared to other companies in the same field. All items were measured by using 6-point Likert scales. Means of multiple items measuring a construct were used as variables based on acceptable reliability and validity. To reduce multi-collinearity problems generated on the regression analysis of interaction terms, centered data were used for HRI, LO, and Innovation effect on regression analyses. In group comparison, large-sized companies were superior on annual sales, annual net profit, the number of new products/services in the last 3 years, the number of new processes advanced in the last 3 years, and the number of R&D personnel, compared to small and medium-sized companies. Also, large-sized companies indicated a higher level of HRI, LO, HRI-LO interaction, innovation effect and business performance than did small and medium-sized companies. The results indicate that large-sized companies tend to have more innovative human resources and invest more on learning orientation than did small-sized companies, therefore, large-sized companies tend to have more success of a new product/service in the market, generating better business performance. In order to test research hypotheses, a series of multiple-regression analysis was conducted. In the regression analysis examining the impact on innovation effect, important results were generated as : 1) HRI, LO, and HRI-LO affected innovation effect, and 2) company size indicated a moderating effect. Based on the result, the impact of HRI on innovation effect would be greater in small and medium-sized companies than in large-sized companies whereas the impact of LO on innovation effect would be greater in large-sized companies than in small and medium-sized companies. In other words, innovative workforce would be more important in making new products/services that would be successful in the market for small and medium-sized companies than for large-sized companies. Otherwise, learning orientation culture would be more effective in making successful products/services for large-sized companies than for small and medium-sized companies. Based on these results, research hypotheses 1 and 2 were supported. In the analysis of a regression examining the impact on business performance, important results were generated as : 1) innovation effect, LO, and HRI-LO affected business performance, 2) HRI by itself did not have a direct effect on business performance regardless of company size, and 3) company size indicated a moderating effect. Specifically, an effect of the HRI-LO interaction on business performance was stronger in large-sized companies than in small and medium-sized companies. It means that the synergy effect of innovative human resources and learning orientation culture tends to be stronger as company is larger. Referring to these result, research hypothesis 3 was partially supported whereas hypothesis 4 was supported. Based on research results, implications for companies were generated. Regardless of company size, companies need to develop the learning orientation corporate culture as well as human resources' innovativeness together in order to achieve successful development of innovative products and services as well as to improve sales and profits. However, the effectiveness of the HRI-LO interaction would be varied by company size. Specifically, the synergy effect of HRI-LO was stronger to make a success of new products/services in small and medium-sized companies than in large-sized companies. However, the synergy effect of HRI-LO was more effective to increase business performance of large-sized companies than that of small and medium-sized companies. In the case of small and medium-sized companies, business performance was achieved more through the success of new products/services than much directly affected by HRI-LO. The most meaningful result of this study is that the effect of HRI-LO interaction on innovation effect and business performance was confirmed. It was often ignored in the previous research. Also, it was found that the innovativeness of human workforce would not directly influence in generating good business performance, however, innovative human resources would indirectly affect making good business performance by contributing to achieving the development of new products/services that would be successful in the market. These findings would provide valuable managerial implications specifically in regard to the development of corporate culture and education program of small and medium-sized as well as large-sized companies in a variety of fields.

Roll Force Prediction of High-Strength Steel Using Foil Rolling Theory in Cold Skin Pass Rolling (고강도강의 냉간 조질 압연 시 호일 압연이론을 이용한 압연하중의 예측)

  • Song, Gil Ho;Jung, Jae Chook
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.2
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    • pp.271-277
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    • 2013
  • Skin pass rolling is a very important process for applying a certain elongation to a strip in the cold rolling and annealing processes, which play an important role in preventing the stretching of the yield point when the material is processed. The exact prediction of the rolling force is essential for obtaining a given elongation with the steel grade and strip size. Unlike hot rolling and cold rolling, skin pass rolling is used to apply an elongation of within 2% to the strip. Under a small reduction, it is difficult to predict the rolling force because the elastic deformation behavior of the rolls is complicated and a model for predicting the rolling force has not yet been established. Nevertheless, the exact prediction of the rolling force in skin pass rolling has gained increasing importance in recent times with the rapid development of high-strength steels for use in automobiles. In this study, the possibility of predicting the rolling force in skin pass rolling for producing various steel grades was examined using foil rolling theory, which is known to have similar elastic deformation behavior of rolls in the roll bite. It was found that a noncircular arc model is more accurate than a circular model in predicting the roll force of high-strength steel below TS 980 MPa in skin pass rolling.

Geochemical Characteristics of Allanite from Rare Metal Deposits in the Chungju Area, Chungcheongbuk-Do (Province), Korea (충주지역 희유원소광상에서 산출되는 갈렴석의 지구화학적특성)

  • Park, Maeng-Eon;Kim, Gun-Soo;Choi, In-Sik
    • Economic and Environmental Geology
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    • v.29 no.5
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    • pp.545-559
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    • 1996
  • Rare metal (Nb-Zr-REE) ore deposits are located in the Chungju area. Geotectonically, the rare metal ore deposits are situated in the transitional zone between Kyeonggi massif and Okcheon belt. The rare metal deposits are distributed in Kyemyeongsan Formation which consist of schist and alkaline igneous rocks. Alkali granite has suffered extensive post-magmatic metasomatism and hydrothermal processes. The ore contains mainly Ce-La, Ta-Nb, Y, Y-Nd, Nd-Th group minerals. More than 15 RE and REE minerals are found in the ore deposits. Allanite, one of the Ce-La rich REE minerals belonging to the epidote group, is the most common mineral in the studied area. The allanite- bearing rocks may be devided into seven types by features of occurrence and mineral associations; zircon type (ZT), allanite-vein type (AT), feldspar type (KT), fluorite type (FT), quartz-mica type (QT), iron-oxide type (MT), and amphibole type (HT). The allanite veins (AT) and zircon rich rocks (ZT) contain the highest total REE contents. Differences in REE abundance can be interpreted in terms of varying portions of magmatic hydrothermal fluid. Petrographical and chemical data are presented for allanites which were collected from different types. The allanites show wide variations in optical properties, due in part to differences in their chemical composition (depending on the types) and to the degree of crystallinity of the individual specimens. Allanite metamicts in biotite are generally surrounded by well developed pleochroic haloes. Usually, allanite is accompanied by zircon and other REE-bearing minerals. CaO and total REE contents $({\sum}RE_2O_3)$ range from 9.29 to 18.79% and 11.66 to 26.31%, respectively. Also, SiO, (28.87~32.61%), $Al_2O_3$ (8.30~16.88%), and $Fc_2O_3$ (16.74~24.38%) contents show varying contents from type to type. The ${\sum}RE_2O_3$ of allanite has positive relationships with $Fe_2O_3$ and negative relaton with CaO, $SiO_2$, and $Al_2O_3$ Backscattered electron microscope images (BEl) of allanite shows that the its mineral composition and texture is very complex. The allanite-bearing hosts show distinct light REE enrichment with strong negative Eu anomaly except for HI. The HT has an almost flat REE distribution pattern with a small negative Eu anomaly. The chemical variation of the allanites with occurrences and mineral association can be related to condition of temperature and oxidation states in precipitation environment.

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Studies on the Mineralogical Characteristics of Apple Orchard Soils (사과원토양(園土壤)의 광물학적특성(鑛物學的特性)에 관(關)한 연구(硏究))

  • Lee, Mahn Jung
    • Korean Journal of Soil Science and Fertilizer
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    • v.6 no.3
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    • pp.141-152
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    • 1973
  • The mineralogical studies of the eleven sub-soil samples derived from granite, granodiorite, diorite and arkose sandstone, taken from apple orchards in the province of Kyungsangbukdo, Korea are made to investigate the relationships between the mineral weathering, soil forming processes and mineralogical composition. The fine sand fraction (less than 0.2mm) and the clay fraction (less than 2 micron) are dispersed with the shaker after hydrogen peroxide treatment for the removal of organic matter, and separated from each suspension by gravity sedimentation. The fine sand are observed by mineral microscope and the clay are observed by X-ray diffraction patterns, differential thermal analysis curves and infrared spectrum. The outline of the results are as follows. 1. The primary minerals ; Quartz, changed-feldspar, plagioclase, alkali-feldspar are dominant in almost all samples, and some samples contain an appreciable amount of hornblende, biotite, muscovite and plant opal. There are also those samples which contain very small quantity of pyroxene group, tourmaline, epidote, cyanite, magnetite, volcanic glass and zircon. They are mainly derived from weathering products of granite, granodiorite, diorite, arkose or its mixtures. 2. All samples contain expanding or nonexpanding $14{\AA}$ minerals, illite and kaolin minerals, and some samples contain chlorite, cristobalite, gibbsite, and those primary minerals as quartz and feldspar, but the quantities vary according to the parent matrials. 3. Non-expanding $14{\AA}$ minerals may be dioctahadral vermiculite which sandwiches gibbsite layer or chlorite in between layer lattices. 4. As for clay minerals, montmorillonite was principal component in the samples derived from weathering products of arkose sandstone and tertiary. Minerals which are derived from weathering products of arkose have kaolin minerals and vermiculite as their principal component, and minerals derived from weathering products of acidic rock group are generally classified into two groups, the kaolin mineral group, and the kaolin minerals and vermiculite group.

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Paleomagnetism, Stratigraphy and Geologic Structure of the Tertiary Pohang and Changgi Basins; K-Ar Ages for the Volcanic Rocks (포항(浦項) 및 장기분지(盆地)에 대한 고지자기(古地磁氣), 층서(層序) 및 구조연구(構造硏究); 화산암류(火山岩類)의 K-Ar 연대(年代))

  • Lee, Hyun Koo;Moon, Hi-Soo;Min, Kyung Duck;Kim, In-Soo;Yun, Hyesu;Itaya, Tetsumaru
    • Economic and Environmental Geology
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    • v.25 no.3
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    • pp.337-349
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    • 1992
  • The Tertiary basins in Korea have widely been studied by numerous researchers producing individual results in sedimentology, paleontology, stratigraphy, volcanic petrology and structural geology, but interdisciplinary studies, inter-basin analysis and basin-forming process have not been carried out yet. Major work of this study is to elucidate evidences obtained from different parts of a basin as well as different Tertiary basins (Pohang, Changgi, Eoil, Haseo and Ulsan basins) in order to build up the correlation between the basins, and an overall picture of the basin architecture and evolution in Korea. According to the paleontologic evidences the geologic age of the Pohang marine basin is dated to be late Lower Miocence to Middle Miocene, whereas other non-marine basins are older as being either Early Miocene or Oligocene(Lee, 1975, 1978: Bong, 1984: Chun, 1982: Choi et al., 1984: Yun et al., 1990: Yoon, 1982). However, detailed ages of the Tertiary sediments, and their correlations in a basin and between basins are still controversial, since the basins are separated from each other, sedimentary sequence is disturbed and intruded by voncanic rocks, and non-marine sediments are not fossiliferous to be correlated. Therefore, in this work radiometric, magnetostratigraphic, and biostratigraphic data was integrated for the refinement of chronostratigraphy and synopsis of stratigraphy of Tertiary basins of Korea. A total of 21 samples including 10 basaltic, 2 porphyritic, and 9 andesitic rocks from 4 basins were collected for the K-Ar dating of whole rock method. The obtained age can be grouped as follows: $14.8{\pm}0.4{\sim}15.2{\pm}0.4Ma$, $19.9{\pm}0.5{\sim}22.1{\pm}0.7Ma$, $18.0{\pm}1.1{\sim}20.4+0.5Ma$, and $14.6{\pm}0.7{\sim}21.1{\pm}0.5Ma$. Stratigraphically they mostly fall into the range of Lower Miocene to Mid Miocene. The oldest volcanic rock recorded is a basalt (911213-6) with the age of $22.05{\pm}0.67Ma$ near Sangjeong-ri in the Changgi (or Janggi) basin and presumed to be formed in the Early Miocene, when Changgi Conglomerate began to deposit. The youngest one (911214-9) is a basalt of $14.64{\pm}0.66Ma$ in the Haseo basin. This means the intrusive and extrusive rocks are not a product of sudden voncanic activity of short duration as previously accepted but of successive processes lasting relatively long period of 8 or 9 Ma. The radiometric age of the volcanic rocks is not randomly distributed but varies systematically with basins and localities. It becomes generlly younger to the south, namely from the Changgi basin to the Haseo basin. The rocks in the Changgi basin are dated to be from $19.92{\pm}0.47$ to $22.05{\pm}0.67Ma$. With exception of only one locality in the Geumgwangdong they all formed before 20 Ma B.P. The Eoil basalt by Tateiwa in the Eoil basin are dated to be from $20.44{\pm}0.47$ to $18.35{\pm}0.62Ma$ and they are younger than those in the Changgi basin by 2~4 Ma. Specifically, basaltic rocks in the sedimentary and voncanic sequences of the Eoil basin can be well compared to the sequence of associated sedimentary rocks. Generally they become younger to the stratigraphically upper part. Among the basin, the Haseo basin is characterized by the youngest volcanic rocks. The basalt (911214-7) which crops out in Jeongja-ri, Gangdong-myon, Ulsan-gun is $16.22{\pm}0.75Ma$ and the other one (911214-9) in coastal area, Jujon-dong, Ulsan is $14.64{\pm}0.66Ma$ old. The radiometric data are positively collaborated with the results of paleomagnetic study, pull-apart basin model and East Sea spreading theory. Especially, the successively changing age of Eoil basalts are in accordance with successively changing degree of rotation. In detail, following results are discussed. Firstly, the porphyritic rocks previously known as Cretaceous basement (911213-2, 911214-1) show the age of $43.73{\pm}1.05$$49.58{\pm}1.13Ma$(Eocene) confirms the results of Jin et al. (1988). This means sequential volcanic activity from Cretaceous up to Lower Tertiary. Secondly, intrusive andesitic rocks in the Pohang basin, which are dated to be $21.8{\pm}2.8Ma$ (Jin et al., 1988) are found out to be 15 Ma old in coincindence with the age of host strata of 16.5 Ma. Thirdly, The Quaternary basalt (911213-5 and 911213-6) of Tateiwa(1924) is not homogeneous regarding formation age and petrological characteristics. The basalt in the Changgi basin show the age of $19.92{\pm}0.47$ and $22.05{\pm}0.67$ (Miocene). The basalt (911213-8) in Sangjond-ri, which intruded Nultaeri Trachytic Tuff is dated to be $20.55{\pm}0.50Ma$, which means Changgi Group is older than this age. The Yeonil Basalt, which Tateiwa described as Quaternary one shows different age ranging from Lower Miocene to Upper Miocene(cf. Jin et al., 1988: sample no. 93-33: $10.20{\pm}0.30Ma$). Therefore, the Yeonil Quarterary basalt should be revised and divided into different geologic epochs. Fourthly, Yeonil basalt of Tateiwa (1926) in the Eoil basin is correlated to the Yeonil basalt in the Changgi basin. Yoon (1989) intergrated both basalts as Eoil basaltic andesitic volcanic rocks or Eoil basalt (Yoon et al., 1991), and placed uppermost unit of the Changgi Group. As mentioned above the so-called Quarternary basalt in the Eoil basin are not extruded or intruaed simultaneously, but differentiatedly (14 Ma~25 Ma) so that they can not be classified as one unit. Fifthly, the Yongdong-ri formation of the Pomgogri Group is intruded by the Eoil basalt (911214-3) of 18.35~0.62 Ma age. Therefore, the deposition of the Pomgogri Group is completed before this age. Referring petrological characteristics, occurences, paleomagnetic data, and relationship to other Eoil basalts, it is most provable that this basalt is younger than two others. That means the Pomgogri Group is underlain by the Changgi Group. Sixthly, mineral composition of the basalts and andesitic rocks from the 4 basins show different ground mass and phenocryst. In volcanic rocks in the Pohang basin, phenocrysts are pyroxene and a small amount of biotite. Those of the Changgi basin is predominant by Labradorite, in the Eoil by bytownite-anorthite and a small amount pyroxene.

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