• Journal of Korean Association for Spatial Structures
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• v.21 no.3
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• pp.25-34
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• 2021

This study develops a new device system for measuring a slope of object with non-adhesive, non-contact and non-face-to-face, namely Inclinometer Slope Laser Measuring (ISLM), that is applicable in the field. This system includes cradle, laser, camera, and computer and the filming and is performed after laser projection at programmed intervals. After measuring the amount of displacement converted to numerical values, these values can then be transferred to the office using the selected data transmission method. The obtained results from the test carried out to verify the reliability of the ISLM system indicated that the ISLM system can measure with accurately level of 0.1mm/Pixel at 1m distance and when increasing the camera resolution, the precision might increase proportionally. Therefore, the proposed measure system may widely apply on-site for various constructions, especially, in the case of object with very high surface temperature where exhibits difficulty to directly measure the adjacent structures. However, due to the sensitive reaction to the illuminance, this method can be applied with caution at times of large changes in illuminance, such as at dawn and at dusk.

• The Journal of Asian Finance, Economics and Business
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• v.10 no.2
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• pp.1-14
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• 2023

The purpose of this study is to discover the possible solutions for the problem faced by academicians during online learning by means of employing qualitative and quantitative approaches. Using a qualitative approach, selected academicians were interviewed, and their feedback was transcribed and used to develop the survey instrument. The quantitative research design was later used to determine the most plausible solutions for the problem that could be obtained and implemented by distributing the questionnaire to academicians at a public university. Multiple regression analysis results indicate that work-life conflict and lack of support are the main contributors to academicians' mental and emotional health issues. The study's major findings help higher education institutions craft appropriate strategies to enhance the effectiveness of online teaching and learning by providing the necessary support to the academicians. The study's findings suggest that academicians should separate work and family requirements to concentrate on their job. Furthermore, the immediate supervisor must be considerate in determining the number of tasks, the deadlines, and the assistance required to complete the task. Lastly, academicians must equip themselves with emotional intelligence to cope with stressors.

• Journal of Families and Better Life
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• v.11 no.1
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• pp.80-92
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• 1993

The purpose of this study is to provide information of the structure of the social support network and life interchange with the social support network which influence the life satisfaction in the rural elderly. The sample of this study was selected from the elderly living in Korea rural areas. 350 out of 363 respondents were finally selected as datum sources. The methodological instrument was the questionnaire. The major findings of this study can be summarized as follows: First most of rural elderly had the relationship all kinds of social support network-family kin neighbors & friend. And the family was the primary source of support network. The com-mon size of the social support network was 1-3 persons. Second the frequency of the contact with the family the neighbors & the friends were almost daily and they were interacting in a near distance. The interchange with the social support network was high. Life satisfaction of the rural elderly was low. Third the interchange with the family and the kin the emotional interchange had the effect upon life satisfaction. Also the economic service support was significant in the kin and the neighbors.

• Journal of information and communication convergence engineering
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• v.21 no.3
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• pp.252-260
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• 2023

A bullet launcher can be developed as a smart instrument, especially for use in the military section, that can track, identify, detect, mark, lock, and shoot a target by implementing an image-processing system. In this research, the application of object recognition system, laser encoding as a unique marker, 2-dimensional movement, and pneumatic as a shooter has been studied intensively. The results showed that object recognition system could detect various colors, patterns, sizes, and laser blinking. Measuring the average error value of the object distance by using the camera is ±4, ±5, and ±6% for circle, square and triangle form respectively. Meanwhile, the average accuracy of shots on objects is 95.24% and 85.71% in indoor and outdoor conditions respectively. Here, the average prototype response time is 1.11 s. Moreover, the highest accuracy rate of shooting results at 50 cm was obtained 98.32%.

• Journal of The Korean Association For Science Education
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• v.15 no.4
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• pp.379-393
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• 1995

In spite of school science learning, the students' conceptions have not been changed easily. Therefore, to make students overcome their non scientific conceptions has been an important issue in science education. The purpose of this study was to identify the conceptions of students and teachers on the motion of the earth and the moon. The instrument was developed for estimating students' understandings of the concepts related to the motion of the earth and the moon. The validity of the instrument was examined by the specialists in Science Educator and Astronomer. At the same time, the two field trials had been executed, and the items were modified. Also, it consists of 12 items including 9 two-tier multiple choice items and 3 multiple choice items. The population of this study consists of 250 eighth-, 299 tenth-, 292 eleventh-grade students, 134 science teachers in secondary school. SPSS/PC+ was adopted for the statistical analysis. The type of misconceptions possessed students were as follows: 1) At 12:00 noon, the sun is directly overhead. 2) First quarter moon is a half of overall surface of the moon. 3) Air don't rotate with the earth surface because it keeps apart from the earth surface. 4) Summer is warmer than winter, because the earth is nearer from the sun in summer. 5) Whenever season is changed, the direction of rotation axis of the earth is changed. 6) The moon is the brightest at the position of new moon, because the distance between the moon and the sun is the shortest and the moon is received strongest sunlight. 7) The moon is not seen at the position of real full moon, because it is covered with shadow of the earth. 8) When the moon is not seen in the earth, sunlight is not reached at the moon. The major findings were as follows : 1) The middle school students had more misconceptions than those of high school students. And female students had more misconceptions than those of male ones. 2) The rate of correct answer and the type of conception in the tenth grade students were very similar with eleventh grade students. 3) The higher cognitive level, the better development of scientific conception and the less misconception. Also, the correlation coefficient between scientific conception score and GALT score was 0.57. 4) The students in scientific part had higher the rate of correct answer than those of students in human part and the former had less misconception than the latter. 5) The rate of correct answer about model and figure items was lower than descriptive ones, because they did not understand about figures itselves. These types of misconceptions will be used for science instruction and studies of other conceptions need.

• Journal of the Korean Society for Railway
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• v.12 no.3
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• pp.405-411
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• 2009

Railway signaling system in a rapid transit using the ATC system the approved a speed limit to a train and a part of signaling system in a metro approved a distance which is possible to move. Referring to the way of transmitting train control information, there are the one transmitting it to the on-board system of a train using the direct track, the another transmitting it establishing an instrument, and the other transmitting an instrument by a railway track. The one is the method using the direct track as a conductor for composing the part of the track and attaining the information controlling a train by transmitting a signal to the track. It is used for the high-speed railway and the subway. The method using the track attains information by transmitting it to returned information, and the on-board system of a train attains it by magnetic coupling. Because many reinforcing bars on the concrete slab track are used, interaction between a rail and a reinforcing bar that is not produced on ballast track is made. Due to the interaction, the electric characteristic of rail is changed. In the current paper, we numerically computed the coupling coefficient between the rail and the reinforcing bar based on the concrete slab track throughout the model related to the rail and the reinforcing bar using the concrete slab track that is used in the second interval of the Gyeongbu high-speed railway, and we defined the coupling coefficient not changed in the electric characteristic of rail in the condition that there is no interaction between the rail and the reinforcing bar.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.1
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• pp.153-160
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• 2010

It is necessary to determine accurate 3-dimensional coordinates of the building corner points that could be control or check points in order to verify the accuracy of 3D digital maps in the near future. The usual process of obtaining the coordinates of the building corner points is to set up the ground control points with a GPS and then to practice terrestrial survey such as distance or angle measurements. However, since an error in the ground control points can be propagated through the terrestrial survey into the final coordinates of the buildings, accurately should be considered as much as possible. The actual effect of the GPS-derived ground control point error on the estimates of the unknowns through the terrestrial survey is mathematically analyzed, and the simulation data is tested numerically. The error of the ground control points is tested in the cases of 1-4 cm for the horizontal components and 2-8 cm for the vertical component. The vertical component error is assigned twice the horizontal ones because of the characteristics of the GPS survey. The distance measurement is assumed for convenience and the precision of the estimated coordinates of the building corner points is almost linearly increased according to the errors of the ground control points. In addition, the final estimates themselves can vary by the simulated random errors depending on the precision of the survey instrument, but the precision of the estimates is almost independent of survey accuracy.

• Journal of Elementary Mathematics Education in Korea
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• v.16 no.3
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• pp.359-388
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• 2012

The study aims to extract the framework of sub-factors of spatial sense, to develop test instruments based on the framework to investigate the actual spatial sense ability of fourth to sixth graders in elementary school and to analyze the results. According to the framework of sub-factors of spatial sense of the study, spatial sense has two factors of spatial visualization and spatial orientation. Spatial visualization is divided into mental rotation, mental transformation and figure-ground perception while spatial orientation is categorized into direction sense, distance sense, and location sense. Based on the framework, the test instrument for spatial sense ability was developed and the test was conducted to 430 fourth to sixth students in five elementary schools in capital areas. The following conclusions were drawn from the results obtained in the study. Firstly, the higher school year gets, the more spatial sense grows. However, spatial visualization is developed much more than spatial orientation and their order is reversed with higher graders. Secondly, the most insufficient abilities among fourth to sixth elementary school students' spatial sense were mental transformation of spatial visualization and location sense of spatial orientation. Thirdly, the reasons of differences in sub-factors of spatial sense and graders seem to be from effects of students' learning experiences of spatial sense of mathematics curriculum and the complexities of test items.

• Journal of environmental and Sanitary engineering
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• v.18 no.3 s.49
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• pp.27-34
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• 2003

An objective of local exhaust hood design is to design the hood to operate as efficiently as possible. The greatest loss normally occurs at the entrance to the duct, due to the vena contracta in the throat of the duct. This can be accomplished by minimizing the loss that results from the vena contracta. There have been little studied to be cost-effective approach as installing simple instrument inside the throat of the hood. The aims of this paper were to minimize entry loss using inner square, and to measure the effect of inner square when installed inside hood throat. The results of this study were as follows; First, the magnitude of vena contracta could be considered as the difference between direct measured velocity and calculated velocity, which is from Bernoulli theory. In circle hood, calculated velocity and direct measured velocity were 10.7m/sec and 10.3n/sec, respectively. And the calculated velocity and direct measured velocity in square hood were 7.7m./sec and 6.5m/sec, respectively. Second, effect of inner square by width was carried out. The widths of inner square were L/1(18cm), L/2(9cm), L/3(6cm) and L/6(3cm). In case inner square was installed with 3cm width, the entry of coefficient was 0.93, comparing with 0.85 of entry of coefficient of general hood. Third, effect of inner square by distance from hood inside surface to inner square was carried out. The distances were L/3(6cm), L/6(3cm), L/9(2cm) and L/l8(1cm). In case the distance was 3cm the best efficiency was shown (Ce= 0.93). Fourth, effect of inner square by location from hood entry to duct inside was carried out. The locations of inner square were entry(0cm), L/6(3cm), L/3(6cm), L/2(9cm) and L/l(12cm). In case the location was 0cm, 3cm and 6cm the entry of coefficients were 0.93, 0.92 and 0.90, respectively.

• Journal of Korean Ophthalmic Optics Society
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• v.15 no.3
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• pp.281-286
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• 2010

Purpose: This research provided basic data for refraction by comparing the corrected diopter of trial lens and phoropter. Methods: We compared the corrected diopter of trial lens and phoropter, and analyzed statistical significance and relations of the spherical lens corrected diopter and cylindrical lens corrected diopter according to the types (trial lens and phoropter) of subjective refractive instruments. Also we analyzed statistical significance and relations between cylindrical lens corrected diopter at the astigmatism and the types (trial lens and phoropter) of subjective refractory instruments. Results: When we measured the corrected diopter of simple myopia, the mean value for corrected diopter was S-2.74D using the trial lens and S-2.65D using the phoropter. So the corrected diopter was 0.09D smaller when measured by phoropter. The degree of astigmatism was measured C-0.81D using the trial lens and C-0.77D using the phoropter which showed that the measured value was 0.04D smaller using the phoropter. On correlation analysis between the refractive instruments (trial lens and phoropter) and the corrected diopter, there was significant (p<0.01) strong correlation between refractory machine and corrected spherical diopter (r=0.996) and the correlation between refractory machine and corrected cylindrical diopter was r=0.986 and was also significant (p<0.01). Conclusions: The use of phoropter than trial lens was more desirable when performing refraction on high myopia (simple refractive error, high astigmatism), and when using trial lens, you should consider the vertex distance and the gap between overlapped lenses before prescription.