• Geophysics and Geophysical Exploration
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• v.12 no.1
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• pp.33-40
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• 2009

In field surveys using the dipole-dipole electrical resistivity method, we often encounter negative apparent resistivity. The term 'negative apparent resistivity' refers to apparent resistivity values with the opposite sign to surrounding data in a pseudosection. Because these negative apparent resistivity values have been regarded as measurement errors, we have discarded the negative apparent resistivity data. Some people have even used negative apparent resistivity data in an inversion process, by taking absolute values of the data. Our field experiments lead us to believe that the main cause for negative apparent resistivity is neither measurement errors nor the influence of self potentials. Furthermore, we also believe that it is not caused by the effects of induced polarization. One possible cause for negative apparent resistivity is the subsurface geological structure. In this study, we provide some numerical examples showing that negative apparent resistivity can arise from geological structures. In numerical examples, we simulate field data using a 3D numerical modelling algorithm, and then extract 2D sections. Our numerical experiments demonstrate that the negative apparent resistivity can be caused by geological structures modelled by U-shaped and crescent-shaped conductive models. Negative apparent resistivity usually occurs when potentials increase with distance from the current electrodes. By plotting the voltage-electrode position curves, we could confirm that when the voltage curves intersect each other, negative apparent resistivity appears. These numerical examples suggest that when we observe negative apparent resistivity in field surveys, we should consider the possibility that the negative apparent resistivity has been caused by geological structure.

• Geophysics and Geophysical Exploration
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• v.8 no.4
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• pp.251-261
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• 2005

The quality of MT (magnetotellurics) data highly depends on the level of artificial noise form industrial sources. We have conducted the feasibility study of MT noise modelling using digital spatial data and spatial modelling through the comparison between the predicted and the measured MT noises. A simple noise model predicting the intensity of electromagnetic field radiated from the latent noise sources, that is, the electric facilities in the building, road and high-voltage powerline, is developed in consideration of the propagation property of electromagnetic waves. From the analysis of correlation between the predicted and the measured noise power, the correlation coefficients of electric field are higher than those of magnetic field in whole frequency band. The magnetic field component has the high correlation in the narrow band near 60 Hz only. The spatial noise modelling proposed in this study would provide some useful informations for the MT surveys in the noisy environment like urban area.

• Publications of The Korean Astronomical Society
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• v.32 no.1
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• pp.235-237
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• 2017

The AKARI NEP Deep Field Survey is an international multiwavelength survey over $0.4deg^2$ of the sky. This is the deepest survey made by the InfraRed Camera (IRC) of the infrared astronomical satellite AKARI with 9 filters continuously covering the $2-25{\mu}m$ range, including three filters in the Spitzer gap between the IRAC and MIPS coverages. This enabled us to make sensitive MIR detection of AGN candidates at z~ 1, based on hot dust emission in the AGN torus. It is also efficient in detecting highly obscured Compton-thick AGN population. In this article, we report the first results of X-ray observations on this field. The field was covered by 15 overlapping Chandra ACIS-I observations with a total exposure of ~300 ks, detecting ${\approx}450$ X-ray sources. We utilize rest-frame stacking analysis of the MIR AGN candidates that are not detected individually. Our preliminary analysis shows a marginal detection of the rest-frame stacked Fe $k{\alpha}$ line from our strong Compton-thick candidates.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.5
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• pp.487-493
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• 2014

A geographic survey, which requires much of working hours in the digital mapping process, is consisted with the complementary survey and the attribute survey of topography and topographic features, and depended on the field survey. In previous research, using the location-based image had been recommended for diminishing the workload of field survey and post processing. For this research, we have developed the hardware and software for gathering and processing the location-based images with referencing results from the previous research. Those Geographic surveys were performed using developed system on 1/5,000 map sheets for Si and Gun area, respectively. The results have been evaluated as the mobile geographic survey system were able to replace the large part of field survey, and also the working hours were decreased by 37.5% at Si area. However, the complementary survey was needed for the attributes of topography and topographic features that were occluded by the parked vehicles or located in the areas without entry of vehicles.

• Journal of the Korean Society of Fashion and Beauty
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• v.5 no.1 s.12
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• pp.34-50
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• 2007

This study was designed to measure customer awareness about their own scalp and hair treatment based on survey, through the theoretical background of scalp physiology field by considering scalp and hair treatment. This was to provide a principal data about scalp and hair treatment for the beauty industry. Also, the data about the awareness of customers will be used to search for a direction far basic beauty services in the scalp and hair treatment field. Four hundred customers in beauty parlors, dermatology clinics, skin care institutes, and scalp institutes, living in the North Cheolla Province were surveyed. They were 25 years old and over. The surveys were performed over a period of ten days from November 18th to 28th in 2005. The collected data was analyzed by SPSS. Frequency and percentage were used to draw typical feature of subjects. Chi-square test, frequencies, t-test and One-way ANOVA were performed to consider awareness of customers for hair treatment as well as hair character and scalp hair. This study was able to estimate the awareness of customers by putting together between the recognition of scalp based on the special quality of hair and the recognition of hair and scalp treatment. In conclusion, the scalp and hair did not act independently. In order to have healthy hair, one must posses a healthy, and physiologically sound scalp. In order for beauticians to properly serve their clientele who require hair and scalp treatment, one must be able to comprehend and understand the field of scalp and hair treatment.

• Journal of the Korea Convergence Society
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• v.6 no.4
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• pp.47-54
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• 2015

This study was conducted an convergence research on 210 mothers in order to examine the effect of golf on subjective happiness of mothers who have children with disabilities. The factors were conducted surveys using SPSS WIN 18.0 program. Firstly, were mostly 40s, college graduates, Buddhists or had no religion, had housekeeping as occupation, had average household income, and most of them were healthy. In addition, descriptive statistics on their years of experience in golf, golf strokes, field, practice frequency, and practice hours were all above average. Secondly, significant correlations were suggested between experience in golf, golf strokes, field, practice frequency, silence during practice hours, and in the subjective happiness of negative correlation as a result of analysing the correlations between the factors. Thirdly, the field, practice frequency, and practice hours affected the subjective happiness.

• Fire Science and Engineering
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• v.24 no.3
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• pp.113-118
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• 2010

FSR has been placed and operated in the Daegu Fire & Safety Department on a trial basis since September 2009. This research proposes a direction for developing the robot, which will provide greater field adaptability and efficiency through analyzing in-depth interviews and surveys of firefighters who have operated the robot. Analysis has shown that an Assistant FSR is expected to enhance maneuverability and improve the performance of wheels, which will increase the capacity for navigating obstacles. The Field FSR needs improvements in convenience of control, making the weight lighter, and stabilization of radio communications to eliminate tangled wires. Overall satisfaction regarding the performance of robots currently in operation is low, while preference toward using the Assistant robot in the field is also low, shown at 8.4%. Therefore, it is urgently necessary to vitalize usage of FSR in the field so that early commercialization of the FSR will contribute to reinforce both growth and competitiveness of the domestic robotics industry.

• Korean Institute of Interior Design Journal
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• v.26 no.1
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• pp.25-32
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• 2017

As the elderly population increases rapidly, existing houses many elderly reside are under poor conditions that they work as a factor to impede on the independent living of elderly people. Thus, improving existing housing environment to suit the needs of elderly life has been required. Academics has been continuously researched on the field considering the importance of elderly housing modification and the importance on the research of this field is projected to be greater with the coming of aging society. Hence, this study has a purpose on analyzing trends of previous studies related to housing modification for the elderly published in Korean academic journals in depth. This study is a content analysis study and analyzed the trend of previous studies with academic journal field, purpose of study, research subject, research area, research method, research content as analysis categories. As a result, previous studies was published the most in natural science academic journals and main stream of research was to suggest direction of housing modification by conducting surveys on actual conditions and needs of single elderly families and to suggest improving the directions of policies related to modification. On the other hand, empirical studies needed to execute housing modification such as standard and method of housing modification and supporting tools are still at minimal level that researches on this field should be conducted additionally. This study is expected to be used as basis to examine the current state of previous studies on housing modification for the elderly and to seek further research directions.

• Journal of People, Plants, and Environment
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• v.24 no.4
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• pp.441-450
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• 2021

Background and objective: The purpose of study is to analyze the three-dimensional (3D) structure by creating a 3D model for green spaces in a park using unmanned aerial vehicle (UAV) images. Methods: After producing a digital surface model (DSM) and a digital terrain model (DTM) using UAV images taken in Mureung Park in Chuncheon-si, we generated a digital tree height model (DHM). In addition, we used the mean shift algorithm to test the classification accuracy, and obtain accurate tree height and volume measures through field survey. Results: Most of the tree species planted in Mureung Park were Pinus koraiensis, followed by Pinus densiflora, and Zelkova serrata, and most of the shrubs planted were Rhododendron yedoense, followed by Buxus microphylla, and Spiraea prunifolia. The average height of trees measured at the site was 7.8 m, and the average height estimated by the model was 7.5 m, showing a difference of about 0.3 m. As a result of the t-test, there was no significant difference between height values of the field survey data and the model. The estimated green coverage and volume of the study site using the UAV were 5,019 m² and 14,897 m³, respectively, and the green coverage and volume measured through the field survey were 6,339 m² and 17,167 m³. It was analyzed that the green coverage showed a difference of about 21% and the volume showed a difference of about 13%. Conclusion: The UAV equipped with RTK (Real-Time Kinematic) and GNSS (Global Navigation Satellite System) modules used in this study could collect information on tree height, green coverage, and volume with relatively high accuracy within a short period of time. This could serve as an alternative to overcome the limitations of time and cost in previous field surveys using remote sensing techniques.

• Journal of the Korean Society for Library and Information Science
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• v.31 no.4
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• pp.187-214
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• 1997

This study surveys science information resources and science information resource services institutions existing in the field of scientific research to analyse their strengths and weaknesses, which provide theoretical foundation of planning an effective and efficient nation-wide science information transfer system for Korea. This study also suggests right directions of developing a centralised system of science information for Korea.