• Journal of Korean Society of Transportation
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• v.14 no.4
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• pp.31-48
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• 1996

This paper develops a disaggregate model system for travel behavior of workers in a metropolitan area. We attempt to develop a set of models for predicting trip generation type, trip purpose, destination, mode choices in each trip on the way from work to home by using the concept of utility maximization of base-to-base tour. The model incorporates the concept that decisions of a trip in a trip in a travel tour depend on decisions of the trips having been made before and decisions of trip planned after of this trip, as well as on current trip conditions. As the structure of the model, the nested logit model is used to avoid a simultaneous model's complexity. The data to be used for estimating the model system are from the person trip survey which was carried out in 1981 in Nagoya metropolitan. Empirical tests of the model for Nagoya metropolitan area show encouraging results and prove the validity of the assumption of this model.

• Hwankyungkyoyuk
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• v.21 no.3
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• pp.1-12
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• 2008

This study is aimed at suggesting ways to develop field trip or learning materials focusing on environment of Jeju seashore in order to make an effective field trip. To perform these purposes, the contents and concepts were analyzed from environment-related 'geological unit' of elementary science textbook. Afterwards, the places having the geological features in coincidence with them are chosen, and investigated, and these regions can develop into geological teaming places for field trip. Each teaming spot focuses on understanding and finding out the characteristic geological environment of rock shore, gravel shore, sand shore, shellfish shore, and tideland shore among Jeju shores. When field trip is conducted at the preparatory stage, students can get advance knowledge on geological concepts from textbook. The activity record paper is presented at the field trip stage where students observe geological phenomena on their own. After field trip is finished, the summary stage is given to solve some problems on the basis of the observed contents. The developed data from this research have its regional limits, but is surely useful for teachers who try to plan field trip when they especially choose the right field trip spots, or plan to make the process for field trip preparation of the environmental education. Furthermore, with this survey and activities, students can take the chance to improve the learning effect through their own experience on environment of Jeju seashore.

• Proceedings of the KWS Conference
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• 2003.05a
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• pp.149-151
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• 2003

The development of lightweight car bodies is the most prominent issue in the automotive industry today, in preparation of environmental regulations such as reduction of CO$_2$ emissions. Also, with the recent implementation of mandatory off-set collision test, many studies have been carried out to enhance the safety of automobiles. Recently, TRIP(Transformation Induced Plasticity) steel has developed as a prominent alternative due to its high strength and superior elongation. In this study, TRIP steel weldability is evaluated with lobe curve, continuous spot welds, shunt effect, and weld of edge position.

• Korean Journal of Metals and Materials
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• v.49 no.4
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• pp.281-290
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• 2011

In order to gain better understanding of the selective surface oxidation and its influence on the galvanizability of a transformation-induced plasticity (TRIP) assisted steel containing 1.5 wt.% Si and 1.6 wt.% Mn, a model experiment has been carried out by depositing Si and Mn (each with a nominal thickness of 10 nm) in either monolayers or bilayers on a low-alloy interstitial-free (IF) steel sheet. After intercritical annealing at $800^{\circ}C$ in a $N_2$ ambient with a dew point of $-40^{\circ}C$, the surface scale formed on 590 MPa TRIP steel exhibited a microstructure similar to that of the scale formed on the Mn/Si bilayer-coated IF steel, consisting of $Mn_{2}SiO_{4}$ particles embedded in an amorphous $SiO_{2}$ film. The present study results indicated that, during the intercritical annealing process of 590 MPa TRIP steel, surface segregation of Si occurs first to form an amorphous $SiO_{2}$ film, which in turn accelerates the out-diffusion of Mn to form more stable Mn-Si oxide particles on the steel surface. During hot-dip galvanizing, particulate $Fe_{3}O_{4}$, MnO, and Si-Mn oxides were reduced more readily by Al in a Zn bath than the amorphous $SiO_{2}$ film. Therefore, in order to improve the galvanizability of 590 TRIP steel, it is most desirable to minimize the surface segregation of Si during the intercritical annealing process.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.3 s.30
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• pp.43-50
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• 2004

This study has an object of searching for appropriateness in applying the trip distribution model by studying the changes of the character of parameter which the model contains and by analyzing and evaluating trip distribution technique out of few steps of pre-estimate technique for the traffic demand through computer simulation centering around Kwangju. Method of this study is investigating the basic theory for trip distribution model and with this grounding, I rearranged it as research data for trip distribution model compatible for Kwangju, using data such as research data on actual state, the statistics annual report and basic plan for traffic full equipment of Kwangju. So, The most stable measure of the type of trip distribution of Kwangju city was produced in Fratar and Detroit model, however, gravity model has a little bit low reliance in sharing of estimation and actual survey although it is astringent in short period.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.2
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• pp.164-171
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• 2003

The side impact behavior has been investigated when the high strength steel 60TRIP(Transformation Induced Plasticity) is replaced for the conventional low-carbon steel for weight reduction of an auto-body. The side impact analysis was carried out as specified in US-SINCAP with the center pillar and the side sill of the conventional steel or 60TRIP. For accurate impact analyses, the dynamic material properties are adopted with the Johnson-Cook model. The analysis results demonstrate that the penetration of the side members is remarkably reduced when 60TRIP is employed for the center pillar and the side sill replacing the conventional steel. The crashworthiness in the side impact is considerably improved with less penetration of the side members and less acceleration of the opposite floor.

• The Journal of the Korea Contents Association
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• v.20 no.6
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• pp.482-497
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• 2020

The purpose of this study is to find out how college students overseas field trip group's social network exist, how the network change during the travel period, and how they are related to trip satisfaction, school involvement and peer relations. College students have an unprecedented school adaptation problem, which is questioning college education practices and measure should be taken. Since travel provides a strong bond with the group of participants, in a similar vein, students' overseas trips are also assumed to strengthen solidarity of students. For 31 trip participants, survey was administered to find out the existence of a distinctive network structure, its changes, and its impact on related variables. First, the network structure of the field trip existed explicitly, in which student representatives held their position in degree centrality. Second, network structure has changed before and after the trip, which is due to the social interaction between participants. Third, the effect on trip performance variables was marginal, even if some participants move to centrality. Forth, field trip satisfaction, school involvement, and peer relations were significant correlated. At the end of the paper, the implications and limitations of the study were included.

• Journal of the Korean Society of Earth Science Education
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• v.8 no.2
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• pp.193-205
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• 2015

In this study, a Virtual geological Field Trip(VFT) learning program using 3D panorama virtual reality techniques was developed to learn about the Gongju city 7 area located in Chungcheongnam-do, Korea. The developed $360^{\circ}$ 3D VFT program can show every face of observational points and interact as zoom-in, zoom-out and image rotation. For the educational effects of the materials, it is provided with a compass, a protractor, enlarged images, pop-up windows, etc.. The program was applied to the class of 35 gifted students in middle school to investigate the effectiveness of the program. The results showed that positive responses of the students were 90% or more. When geological field trip problems like cost, safety, distance occur in geological learning procedure of middle school science, this VFT program can become as a supplementary learning material and a solution.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2503-2508
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• 2013

Single-person households in the Seoul Metropolitan Area have increased sharply during recent 20-30 years. Despite of decreasing in the total population, the number of single-person household is predicted to increase continuously. However, the effect of single-person household growth on the domestic transport sector has not been studied concretely. In this study, the differences on trip generation characteristics by household size and attributes were figured out by analyzing Seoul Metropolitan Area Household Travel Behavior Survey (SMA-HTBS). Firstly, trip generation rates (trips/day/person) were produced by household attribute, household member attribute and trip attribute based on SMA-HTBS. Secondly, trip generation rate of single-person household and that of multi-person (2 or more) household were compared by significance test. It was found that trips generation characteristics of single-person household is quite different from those of multi-person household by housing type, residential type, living area, and transport mode. The result of this paper is expected to contribute developing more sophisticated trip generation model and transport policy reflecting trip generation characteristics of single-person household.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.05a
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• pp.156-160
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• 2001

The effects of TRansformation Induced Plasticity(TRIP) phenomena on the plastic deformation of 0.2C-1.5Si-1.5Mn multiphase steels have been investigated at various heat treatment and stress conditions. In order to estimate the formability, the hole expansion(HE) tests and the tensile tests were carried out. The formability evaluated from the uni-axial tensile tests was quite different from the formability measured from multi-axial HE-tests. Consequently, the formability in the multi-axial stress state decreased due to the extinction of the retained austenite relatively at earlier deformation stage and the production of irregular α' martensite. However, the defects of TRIP-steels were initiated exactly at the boundary between transformed martensite and ferrite matrix regardless of stress state. In addition, new experimental formula is proposed in order to predict the multi-axial formability of the TRIP steels from the results of uniaxial tensile test.