• Journal of Korean Institute of Industrial Engineers
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• v.9 no.1
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• pp.23-31
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• 1983

A group scheduling problem, which is production scheduling problem associated with the concept of group technology, is studied under due date constraints in multi-stage manufacturing systems. The purpose of this paper is to develop and evaluate a practical heuristic procedure for determining group sequence and job sequence within each group to minimize total tardiness in multi-stage manufacturing systems. A heuristic algorithm has been developed by introducing the concept of relative measures of job tardiness and group tardiness for job sequencing and group sequencing, respectively. A numerical example is shown to illustrate the proposed procedure. The heuristic algoirthm is tested by comparisons with problems with known optimal solutions and also with random group schedules for a set of large-size problems. Results indicate that the proposed heuristic algorithm provides good solutions with small computational requirements, and thus is viable for large size problems in practice.

• Journal of the Korean Society of Earth Science Education
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• v.9 no.1
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• pp.97-105
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• 2016

The purpose of this study was to examine the effects of storytelling skill on science concept and science learning motivation. For this study the 5 grade, 2 class was divided into a research group and a comparative group. The class was pre-tested in order to ensure the same standard. The research group had the science class with storytelling skill, and the comparative group had the class of the teacher centered lectures on 11 classes in 8 weeks. The storytelling skill was focused on set the astronomical target wants to set up a story, through the small group discussion, present subject of the story, set the protagonist of the story for smooth configuration of the story, in order to smooth the flow of the story, make up a story around a hero, to make a clear story, decorated with pictures, shapes, graphs, etc, group story, complete with an astronomical(saints) in storytelling. To prove the effects of this study, science concept was split up according to knowledge, inquiry, attitude. Also, science learning motivation consisted of assignment is worth, learning beliefs about control, self efficacy. The results of this study are as follows. First, using storytelling skill was effective in science concept. Second, using storytelling skill was effective in science learning motivation. Also, after using storytelling skill was good reaction by students. As a result, the elementary science class with storytelling skill had the effects of developing science concept and science learning motivation. It means the science class with storytelling skill has potential possibilities and value to develop science concept and science learning motivation.

• Journal of Communications and Networks
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• v.7 no.3
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• pp.294-306
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• 2005

Group oriented multicast applications are becoming increasingly popular in mobile ad hoc networks (MANETs). Due to dynamic topology of MANETs, stateless multicast protocols are finding increased acceptance since they do not require maintenance of state information at intermediate nodes. Recently, several multicast schemes have been proposed which scale better' with the number of multicast sessions than traditional multicast strategies. These schemes are also known as explicit multicast (Xcast; explicit list of destinations in the packet header) or small group multicast (SGM). In this paper, we propose a new scheme for small group' multicast in MANETs named extended explicit multicast (E2M), which is implemented on top of Xcast and introduces mechanisms to make it scalable with number of group members for a given multicast session. Unlike other schemes, E2M does not make any assumptions related to network topology or node location. It is based on the novel concept of dynamic selection of Xcast forwarders (XFs) between a source and its potential destinations. The XF selection is based on group membership and the processing overhead involved in supporting the Xcast protocol at a given node. If the number of members in a given session is small, E2M behaves just like the basic Xcast scheme with no intermediate XFs. As group membership increases, nodes may dynamically decide to become an XF. This scheme, which can work with few E2M aware nodes in the network, provides transparency of stateless multicast, reduces header processing overhead, minimizes Xcast control traffic, and makes Xcast scalable with the number of group members.

• Journal of Korean Elementary Science Education
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• v.30 no.4
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• pp.415-429
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• 2011

In the elementary science classroom, inquiry-based learning activities are often limited to students' hands-on experiences. As a result, students often overlook core concepts they are supposed to acquire from the inquiry activities and show difficulties in applying those concepts in a real life context. To make a connection between the hands-on activities and the concept leaning, a small-group discussion can be considered. In this study, we designed a team-based learning (TBL) model for the elementary science classroom. We developed teaching and learning materials for the "Comfortable Environments" unit in the 6th grade curriculum based on the TBL model. After appling the model with 32 6th grade students, we compared the TBL participants' level of concept understanding and attitudes toward science before and after the intervention, and also compared them with their counterpart control group who participated in a traditional classroom. The results showed that the level of concept understanding of the TBL participants were higher than that of the control group. However, there was no statistically significant difference found in attitudes toward science between the TBL participants and the control group. In addition, the interviews with the TBL participants showed that they positively perceived the TBL experiences.

• Korean Journal of Child Studies
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• v.34 no.1
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• pp.53-70
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• 2013

This study proposes to find out what effects physical effort using props has on infants' ability in relation to their creative physical expression and physical self-concept. This study targets three-year-old preschoolers who attend S and T nursery, located in Yeonje, Busan, of which 16 belong to an experimental group. The research tools used in the study are the creative physical expression test by Kim Eun-Shim(1994), which is the modified version of Bae Hyun-Suck's testing tool(1990), and an altered version of the questionnaire focusing on physical self-concept by Whang Sun-Gack(2001). The experimental group is divided into a large and small sub-group and then physical activities involving props are done by these divided experimental groups once or twice a week for 12 weeks, while outdoor activities are carried out with the comparison group once or twice a week for 12 weeks. For both groups, a total of 20 experiments are done. To obtain answers to the research questions, an individual version of the T-test is conducted using means and standard variations of the experimental and comparison groups. The results of this study are as follows : 1) the physical efforts of the experimental group using props reaped more positive effects as regards creative physical expression than the comparison group, 2) the positive effect on the participants' physical self-concept is also more evident in the case of the experimental group.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.509-518
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• 2011

In this study, we investigated the effects of analogy-generating in small group in elementary science-gifted education upon the types and the mapping errors of student-generated analogies, and the perceptions of the instruction. Fifth graders (N=37) at two science-gifted classes in two elementary schools were selected and assigned to individualistic analogygenerating (IA, n=19) and pair analogy-generating (PA, n=18) groups. After the students of each group performed the experiment and were taught about 'saturated solution' concept in the first class, they administered the test on the self-generating analogies on the concept in the second class. The students in the PA group also administered the test on perceptions of analogy-generating in small group and some of them were interviewed deeply. The results revealed that the students in the PA group made more verbal/pictorial, structural/functional, enriched, and higher systematic analogies than those in the IA group. However, there were little difference between the two groups in the subcategories of artificiality (artificial and everyday) and abstraction (abstract and concrete). The students in the PA group fewer mapping errors than those in the IA group. Many students in PA group perceived the analogy-generating in small group positively upon various cognitive and motivational aspects. However, they also pointed a few disadvantages of the activity. Educational implications of these findings are discussed.

• Journal of the Korean housing association
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• v.24 no.4
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• pp.83-96
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• 2013

With the recent increase in the number of one- and two-person households, demand for small-sized apartments has been on the rise, and lifestyles have seen swift changes to cater to smaller-sized housing. The construction market is shifting toward small-sized apartments, and research is now needed on the lifestyles of those living in small-sized apartments in order to develop suitable housing units. Therefore, this study aims to produce a planning concept for housing units by lifestyle, categorizing residents based on lifestyle and identifying their LDK preferences. Regarding methodology, prior research was reviewed to validate housing-related lifestyle factors and study the lifestyles of those living in small-sized apartments. Lifestyle categories based on housing type were determined by a cluster analysis, and LDK preferences for each lifestyle were analyzed through a survey. These data were then used to propose a planning concept with small-sized apartments for each lifestyle type. Thirty-two factors for categorizing lifestyles were obtained by studying three domains of housing-related lifestyle factors: 'housing values', 'attitudes toward living space', and 'behavior in living space; A total of 648 people living in small-sized apartments were classified into three lifestyle groups: 'True Family Benefiters', 'Smart Shopaholics', and 'Slow Heritage Pursuers'. 'Each group's lifestyle characteristics and socio-demographic features were used to classify the lifestyles of those living in small-sized apartments. The LDK preferences for each lifestyle were analyzed to design a planning concept for small-sized apartment.

• Journal of the Korean housing association
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• v.15 no.6
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• pp.57-65
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• 2004

This paper has attempted to analyze the site planning theories of Raymond Unwin (1863-1940), who is called the father of British town planning. A prominent contribution of his was to establish both the site planning of garden suburb and urban housing style in British type. Here it attempts to analyze how he greatly and firmly established the concept of Housing Group, and how he got this the concept from the life and spatial composition of villages. It could be pointed out that the main factors of the Unwin theory are social mixture, creation of community consciousness and informal landscape design, and that the small enclosed space with plenty of amenity is his main theme. It is pointed out that the Unwin theory is composed of recognizing urban life as totality, and group planning theory, and that he definitely originated a new technique: Housing Group. It is analyzed that the syntactic relations between the group planning theory and housing designs in the English garden suburbs are epitomized in Hampstead Garden Suburb, Middlesex.

• Journal of The Korean Association For Science Education
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• v.21 no.2
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• pp.279-288
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• 2001

In this study, interaction patterns in peer small-group discussions with cognitive conflict strategy (CCS) and those with social consensus strategy (SCS) were compared. Verbal interactions of four small groups (16 students) in learning science concepts were analyzed at the levels of turns, interaction units, and episodes. The frequencies of total turns and knowledge construction turns per discussion for the SCS group were higher than those for the CCS group. Comparing and evaluating hypotheses and discussion worksheets provided were especially effective in increasing metacognitive utterances of the SCS group students. The frequencies of 'most students participating mode', 'elaborative interaction mode', and 'exploratory episode' for the SCS group were higher than those for the CCS group. These suggested that more students in the SCS group participated in small-group discussions and their discussions were more interactive and elaborative. The interactions and episodes of the SCS group were also superior in quality to those of the CCS group.

• Asian Journal of Innovation and Policy
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• v.3 no.1
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• pp.25-49
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• 2014

We wanted to show the different group dynamics of factors for success and failure cases for technology commercialization in small technology-based firms. Existing studies are based on product level, project level, division level or firm level. We deal with technology level, and at small-technology-based firms. This is a longitudinal case study based on 8 cases from Korea. Our study on technology level is a first trial in success and failure studies unlike all existing studies. As a first step, we introduced new categories and factors such as technology attributes and CEO reflecting data, and especially a new concept of launch readiness level. Finally, we adopted correspondence analysis to show the group dynamics. The results are as follows; Technology factors are the most important factors. Second, resource-based factors are more critical in failure cases than success cases and technology factors are more critical to success.