• Journal of The Korean Association For Science Education
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• v.31 no.6
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• pp.931-941
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• 2011

This study aimed to examine the effects of argument-based chemistry laboratory investigations using the Science Writing Heuristic (SWH) approach on students' use and embedding of multimodal representations in summary writing. Participants of this study were thirty-nine freshman students majoring in science education at a National University in Korea. Argument-based chemistry laboratory investigations using the SWH approach were implemented for twenty-three students enrolled in one cohort, and the traditional chemistry laboratory teaching was implemented for 16 students enrolled in the other cohort. Summary writing samples were collected from students before and after the implementation. Summary writing samples produced by students were examined using an analysis framework for examining the use and embeddedness of multimodal representations. Summary writing was categorized into one of verbal mode, symbolic mode, and visual mode. With regard to the embedding of multi-modal representations, summary writing samples were analyzed in terms of 'constructing understanding,' 'integrating multiple modes,' 'providing valid claims and evidence,' and 'representing multiple modes.' Data analysis shows that the students of the SWH group were better at utilizing and embedding multimodal representations in summary writing as they provided evidence supporting their claims. This study provides important implications on pre-service science teacher education.

• The Journal of the Acoustical Society of Korea
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• v.33 no.2
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• pp.87-93
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• 2014

If one identifies the detailed distribution of pressure and axial velocity at a source plane, the position and strength of major noise sources can be known, and the propagation characteristics in axial direction can be well understood to be used for the low noise design. Conventional techniques are usually limited in considering the constant source characteristics specified on the whole source surface; then, the source activity cannot be known in detail. In this work, a method to estimate the pressure and velocity field distribution on the source surface with high spatial resolution is studied. The matrix formulation including the evanescent modes is given, and the nearfield measurement method is proposed. Validation experiment is conducted on a wide duct system, at which a part of the source plane is excited by an acoustic driver in the absence of airflow. Increasing the number of evanescent modes, the prediction of pressure spectrum becomes further precise, and it has less than -25 dB error with 26 converged evanescent modes within the Helmholtz number range of interest. By using the converged modal amplitudes, the source parameter distribution is restored, and the position of the driver is clearly identified at kR = 1. By applying the regularization technique to the restored result, the unphysical minor peaks at the source plane can be effectively suppressed with the filtering of the over-estimated pure radial modes.

• Journal of Korea Port Economic Association
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• v.25 no.4
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• pp.131-146
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• 2009

The purpose of this study is to predict the railway cargo volume on Busan new-port and north-port, in order to revitalize railway transport. This paper is organized as follows. Section 1 presents the description of the objective and methods on this study. Section 2 presents the status of Railway Cargo volumes and Construction plan of railway facilities in Busan New port. Section 3 presents the Forecast Railway Cargo volume using a volume ratio, actual volume records and another predicted datas. Section 4 summarizes our conclusions and further research topics. Especially, korea faces enforcement of green Logistics policy. Modal shift to trail freight transportation is one of ways, but there are no more detail plans. so it need that a cooperation system in government department, a indirect subside policy shift to rail freight transportation from trucking for revitalization of Railway Freight transportation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.4
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• pp.304-312
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• 2011

Grain size analysis was conducted for a total of 402 surface sediments collected from 67 sites along three (upper, middle, and lower) transects corresponding to the high-, mid-, and low-intertidal zone of beach on the Sinjado, Nakdong River estuary in Nov. 2005 and May 2006. Sinja-do beach sediments showed uni-modal grain size distributions, in which the mode of $3.0{\phi}$ was dominant in 2005 whereas the mode of $2.5{\phi}$ in 2006. This coarsening trend was more remarkable in the western side of beach as well as in the mid- and low-intertidal zone. In this study, we focused on investigating characteristics of sediment size changes on the basis of transect data that differ in tidal elevation. For this purpose, a statistical test was applied for transect by transect comparison of grain size parameters such as mean, sorting, and skewness. Mean values between middle and lower transect, sorting values between upper and lower transect, and skewness values over the beach reflected statistically significant temporal changes. Also, mean and skewness parameters showed an inverse relationship which was more stronger in 2006 than in 2005. Temporal changes in Sinja-do beach sediments resulted in decrease of mean and sorting values but increase of skewness values, intensifying the inverse relationship between mean and skewness parameters.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.6
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• pp.769-778
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• 2007

In this paper, excitation systems using linear mass shaker (LMS) and active tuned mass damper (ATMD) are presented in order to simulate the wind induced responses of a building structure. The actuator force for the excitation systems is calculated by using the inverse transfer function of a target structural response to the actuator. Filter and envelop function are used such that the error between the wind and actuator induced responses is minimized by preventing the actuator from exciting unexpected modal response and initial transient response. The analyses results from a 76-story benchmark building problem in which wind load obtained by wind tunnel test is given, indicate that the excitation system installed at a specific floor can approximately embody the structural responses induced by the wind load applied to each floor of the structure. The excitation system designed by the proposed method can be effectively used for evaluating the wind response characteristics of a practical building structure and for obtaining an accurate analytical model of the building under wind load.

• The Journal of the Acoustical Society of Korea
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• v.37 no.2
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• pp.99-109
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• 2018

The precision of the vibration-sensors, contact or non-contact types, is usually satisfactory for the practical measurement applications, but a sensor is confined to the measurement of a point or a direction. Although the precision and frequency span of the low-cost camera are inferior to these sensors, it has the merits in the cost and in the capability of simultaneous measurement of a large vibrating area. Furthermore, a camera can measure multi-degrees-of-freedom of a vibrating object simultaneously. In this study, the calibration method and the dynamic characteristics of the low-cost machine vision camera as a sensor are studied with a demonstrating example of the two-dimensional vibration of a cantilever beam. The planar image of the camera shot reveals two rectilinear and one rotational motion. The rectilinear vibration motion of a single point is first measured using a camera and the camera is experimentally calibrated by calculating error referencing the LDV (Laser Doppler Vibrometer) measurement. Then, by measuring the motion of multiple points at once, the rotational vibration motion and the whole vibration motion of the cantilever beam are measured. The whole vibration motion of the cantilever beam is analyzed both in time and frequency domain.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.1
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• pp.331-351
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• 2016

Digitalized data and literature in scholarly community has developed the concept of digital humanities and cyberscholarship which indicate the characteristics of a new aspect and approach in scholarly activities with digitalized resources or new media. This study was performed in order to identify the changes in national research activities of art and humanities by using a multi-modal approach. The combined methodology of in-depth interview and content analysis on publishing and citing behaviors in literature was executed. The steps of research process is identified as a non-linear combination of 3 parts: developing research idea, developing the research idea to write, and submitting manuscript to publish. Prominent implementations of cyberscholarship were found in the 2nd step for accessing and using research data and literatures. Understanding the characteristics of scholar communication using cyberscholarhip factors in humanities for interdisciplinarity, sophisticating the environment of cyberscholarhip for data sharing, investing and developing archivist and archives, and providing a various platform for accelerating scholarly communication were derived by the panel discussion for developing interdisciplinary research for humanities.

• Journal of the Korean Society for Railway
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• v.19 no.2
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• pp.135-144
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• 2016

It is essential to lighten the weight of switch girders in order to reduce their costs of manufacturing and make it easier to use them in construction. Lightening the weight of switch is also important to the Maglev 3-way switches system, however, the design variables should be considered very carefully if lightening is to be applied to the system, because these variables are vitally related to the levitation stability. Because Urban Maglev trains have a structure in which train bogie wraps around the guiderail, the adjustment of a girder's height is a possible way to reduce the weight. The safety of the application of this concept is ensured by repeated experiments in a test bed, however, due to a lack of space and budget limits, the design parametric study for the system model can substitute for actual application. The purpose of this paper is to study the design parameters that are concerned with levitation stability while a Maglev train is running on the Maglev 3-way system depending on the weight of the switch girders. In this study, switch girder weight is reduced by adjustment of girder height and girders are and modeled as a flexible body. The effect of the adjustment of girder height on the levitation stability can be analyzed by comparing the velocity of the train when it passes the switch girders, with the lateral gap, and the levitation gap which are obtained from the co-simulation of the Maglev train's dynamics model and flexible switching system. The results of this research will be used to design a Maglev switch.

• Science of Emotion and Sensibility
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• v.17 no.3
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• pp.107-116
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• 2014

In the current study, it is suggested that when two emotions are presented through cross-modality, such as auditory and visual, incongruence will influence arousal, recognition, and recall of subjects. The first hypothesis is that incongruent cross-modality does not only increase arousal more than the congruent, but it also increases recall and recognition more than congruent. The second hypothesis is that arousal modulates recall and recognition of subjects. To demonstrate the two hypotheses, our experiment's conditions were manipulated to be congruent and incongruent by presenting positive or negative emotions, visually and acoustically. For dependent variables, we measured recall rate and recognition rates. and arousal was measured by PAD (pleasure-arousal-dominance) scales. After eight days, only recognition was measured repeatedly online. As a result, our behavioral experiment showed that there was a significant difference between arousal before watching a movie clip and after (p<.001), but no difference between the congruent condition and incongruent condition. Also, there was no significant difference between recognition performance in the congruent condition and incongruent condition, but there was a main effect of the clips' emotions. Interestingly after analyzing recognition rates separately depending on clips' emotions, there was a significant difference between congruent and incongruent conditions in the only negative clip (p= .044), not in the positive clip. In a detailed result, recognition in the incongruent condition is more than in the congruent condition. Furthermore, in the case of recall performance, there was a significant interaction between the clips' emotions shown in the clips and congruent conditions (p=.039). Through these results, the effect of incongruence with negative emotion was demonstrated, but an incongruent effect by arousal could not be demonstrated. In conclusion, in our study, we tried to determine the impact of one method to convey a story dramatically and have an effect on memory. These effects are influenced by the subjects' perceived emotions (valence and arousal).

• Economic and Environmental Geology
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• v.25 no.4
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• pp.447-461
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• 1992

The Jurassic granitoids in the study area are divided into the "Gneissose granodiorite" and the "Daebo granodiorite" (1 : 250,000 Jeonju Geological map, 1973). The term of Geochang granodiorite was used in this study instead of "Daebo granodiorite". These granitoids were studied in terms of microscopic observation, petrochemistry, and zircon morphology. The granitoids are mostly granodiorite. Two kinds of progressive variation can also be recognized in the modal quartz~alkali feldspar~plagioclase triangular diagram; the Gneissose granodiorite is in accordance with the trondhjemitic (low k) trend, and the Geochang granodiorite with the granodioritic trend (medium k). The granitoids belong to the calc-alkaline series, and are classified into the I-type (magnetite series). Plagioclase ($An_{25.1}{\sim}An_{30.9}$) in the granitoids shows generally an oligoclase composition. Biotite has a wider range in (Si, Al) solution than in (Fe, Mg) solid solution. Hornblende occurs in a few thin sections of the Geochang granodiorite, and is plotted in the tschermakite field. The zircon prism shows a long variation between the {110} dominant type and the {100} dominant type in the Geochang granodiorite, but only the {110}={100} type in the Gneissose granodiorite. However, zircon crystals in the granitoids are mostly crystallized in a low-to-medium temperature magma. In the PPEF (Prism- Pyramid-Elongation-Flatness) diagram, the Gneissose granodiorite shows a closed scissors type, the Geochang granodiorite, a opened scissors type. It indicates that the Geochang granodiorite might originate from the mixed magma with crustal materials or pre-existed residual magma which had formed the Gneissose granodiorite.