• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.8
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• pp.693-700
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• 2007

We can predict spatial acoustic pressure distribution on the plane of interest by using acoustic holography. However, the information embedded in the distribution plot is usually much more than what we need: for example, source locations and their overall propagation pattern. One possible candidate to solve the problem is complex envelope analysis. Complex envelope analysis extracts slowly-varying envelope signal from a band signal. We have attempted to extend this method to space domain so that we can have spatial information that we need. We have to modulate two dimensional data for obtaining spatial envelope. Although spatial modulation basically follows the same concept that is used in time domain, the algorithm for the spatial modulation turns out to be different from temporal modulation. We briefly describe temporal complex envelope analysis and extend it to spatial envelope of 2-D acoustic field by introducing geometric transformation. In the end, the results of applying the spatial envelope to the holography are envisaged and verified.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.5
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• pp.59-71
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• 2020

Using high-resolution stereoscopic aerial images (in 2008, 2012 and 2016), we conducted to analyze the spatial characteristics affecting evergreen coniferous die-off in the northwestern ridge (major distribution area such as Abies nephrolepis), Seoraksan National Park. The detected number of dead trees at evergreen coniferous forest (5.24㎢) was 1,223 in 2008, was 2,585 in 2012 and was 3,239 in 2016. The number of cumulated dead trees was 7,047 in 2016. In recent years, the number of dead trees increased relatively in the northwest ridge, Seoraksan National Park. Among the analysed spatial factor (altitude, aspect, slope, solar radiation and topographic wetness index), the number of dead trees was increased in the conditions with high altitude, steep slope and dry soil moisture. A spatial distribution of dead tree was divided into 2 groups largely (high altitude with high solar radiation, low altitude with steep slope). In conclusion, the dead trees of evergreen coniferous were concentrated at spatial distribution characteristics causing dryness in the northwestern ridge, Seoraksan National Park.

• Journal of Distribution Science
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• v.21 no.3
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• pp.101-111
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• 2023

Purpose: The first purpose of this study is deriving in-store characteristics that affect the experience of customers using unmanned stores and reveals the value of major services that customers feel and experience. Also, an empirical analysis is conducted on the effect of intelligent consumption value after using unmanned stores on consumption emotions and continuous use intention, and the modulating effect of customers' untact tendency on environmental characteristics and the value of intelligent services is verified. Research design, data and methodology: Samples were taken from 186 people who visited the unmanned store from April to June 2022 to investigate the research model. Results: It was found that the environmental characteristics of unmanned stores had a positive effect on the intelligent service value. Also, the higher the value of intelligent service, the stronger the influence on consumption emotions, and the higher the value of the intelligence service and consumption emotions, the stronger the impact on the intention to use intention. The untact propensity played a role in controlling the relationship between ease of using technology and the intelligent service value and the relationship between spatial arrangement and functionality and intelligent service value. Conclusion: In order to improve unmanned store service in the trend of spreading unmanned stores, it is necessary to not only improve the technology using convenience in terms of store environmental characteristics but also create innovative consumption experiences in terms of space layout, function, and convenience of payment.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.764-771
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• 2009

This research aimed at analyzing relationship between spatial distribution of Pinus densiflora, and topographical factors in Seorak and Chiak national park. 100 m grid size was proven to be suitable for analyzing spatial distribution characteristics of Pinus densiflora. Pinus densiflora appeared mainly on 400 m~800 m of elevation, $15^{\circ}{\sim}30^{\circ}$ of slope and 0~2 of TWI. There were no big differences in appearance frequency of Pinus densiflora area by aspect. There were differences in distribution characteristics of Pinus densiflora between below and above 400 m of elevation. There were no big differences in appearance frequency of Pinus densiflora area above 400 m of elevation but a big differences by topographical factors below 400 m of elevation.

• Journal of Korea Port Economic Association
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• v.27 no.2
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• pp.59-84
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• 2011

The purpose of this study is to analyze the spatial distribution and the linkage characteristics of the warehousing industry in Busan and to provide the policy implications for the warehousing industry in Korean port hinterland. We surveyed the warehousing firms in Busan. Categorizing the warehousing industry into industry types, sizes, and organization types on the basis of the survey, we attempted the point pattern analysis and the proximity analysis using the GIS. The warehousing industry in Busan had changed from a small single-unit firm to a medium or a large firm with a head office or branches. These were distributed in hinterland of North Harbor, South Harbor & Gamcheon Harbor, and Sin-Pyoung & Jang-Rim industrial complex and Sasang Industrial Complex constituting the spatial agglomeration. The warehousing industry in Busan formed the linkages with other sectors of the same logistics to provide manufacturing industries with various other services as well as storage services. The linkages were largely formed in the local scope with spatial proximity, generating the economic gains of agglomeration, which were transformed into the efficiency of the warehousing industry in the local scope to gradually expand the spatial dimensions of the linkages.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.9
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• pp.1198-1206
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• 1997

The flow characteristics of an intermittent fuel injection into a stationary ambient air were investigated using gasoline. The measurements were made by two-channel, air cooling type Phase Doppler Anemometer(PDA) system (DANTEC, 750 MW). And a pintle type injector of MPI (Multi-point Port Injection) system was utilized as a fuel injector. The PDA receiver optic was set up in a 60.deg. C forward scatter arrangement to obtain the optimum scattering signal of fuel droplets. The data were obtained by synchronizing PDA system with the fuel injection period, and the axial and radial velocity and turbulent components of fuel droplets were mainly measured for the analysis of temporal and spatial distribution depending upon the fuel injection pressures.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.6
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• pp.133-144
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• 2018

To suggest the field maintenance plan considering the geographical characteristics of the region, we selected representative regions(plain regione and mountain region) and compared spatial distribution of cultivated land in Muan-gun and Hwasun-gun. Firstly, we examined the distribution characteristics of cultivated land according to the scope of the maintenance object with Fragstats. As a result of that, it was found that the cultivated area except rice paddy had the highest aggregation effect. And then, we developed type classification of maintenance considering geographic characteristics and cultivated crops information. As a result of classification, plain land type Muan region was mostly cultivated land suitable for integrated maintenance. On the other hand, Hwasun, a mountainous terrain, needs small-scale maintenance and road maintenance. Based on these results, it was found that more detailed planning is needed for the upland field infrastructure improvement considering the topographic characteristics.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.3
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• pp.68-84
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• 2020

This study analyzed the relationship between spatial characteristics and heat waves in the distribution area of the elderly population in Changwon, Gyeongsangnam-do. For analysis, the Statistics Census data, the Ministry of Environment land cover, Landsat 8 surface temperature, and the Meteorological Agency's heat wave days data were used. The spatial characteristics of the distribution of the elderly population was classified into 5 types through K-mean cluster analysis considering the land use types. The characteristics of the elderly population by spatial type were higher in the urbanized type(cluster-3), but the proportion of the elderly population was higher in the agricultural and forest area types(cluster-1, cluster-2). In the characteristics of the surface temperature and the heat wave days, the surface temperature was the highest in the urban area, but heat wave days were the highest in the rural area. As a result of analyzing the heat wave characteristics according to the spatial type of the distribution area of elderly population, cluster-2 with the largest area in agricultural areas was highest at 15.95 days, and cluster-3 with a large area in urbanized types was the lowest at 9.41 days and 9.18 days. In other words, the elderly population living in rural areas is more exposed to heat waves than the elderly population living in urban areas, and the damage is expected to increase. The results of this study could be used as basic data to prepare various policy measures for effective management and prevention of vulnerable areas in summer.

• Journal of Agricultural Extension & Community Development
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• v.19 no.4
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• pp.961-987
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• 2012

The present study is to investigate the characteristics and determinants of spatial distribution of strong small farm by defining the term, strong small farm (SSF) extracting the SSF households data dealing with apples, from 2010 Census of Agriculture, Forestry and Fisheries, Korea. Spatial distribution and concentration of SSF are analyzed based on spatial clustering techniques. We construct discrete dependent variables on strong and non-strong small farms and then analyze the determinants of the SSFs using probit model, with independent variables including population and economic characteristics and management characteristics. As of 2010, the apple SSFs, 1,529 households in total, are geographically concentrated in Gyeonsangbuk-do according to the analysis results. The determinants of SSF are similar to those of farms' earnings. When located in the apple producing area, and participating in producers organization while selling products directly, the farm is highly likely an SSF. The findings and results of the present study are expected to provide fundamental information helpful for preparing and implementing policies for SSFs in that the present study investigates the characteristics of SSF, which is a prerequisite step for SSF-related policies.

• The Journal of the Acoustical Society of Korea
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• v.23 no.1E
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• pp.31-39
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• 2004

Backscattered underwater signals from multiple scatterers contain information regarding resolvable spatial distribution of scatterers. This experimental study describes the spectral characteristics of backscattered signal from multiple scatterers, which are regularly or randomly spaced, in terms of their amplitude and phase and a proper signal analysis that will eventually provide scatterer spacing estimation. Air-filled tubes suspended in water, steel balls and plastic tubes buried in the sediment are the multiple scatterers. The cepstrum and the spectral autocorrelation (SAC) methods were used to estimate the scatterer spacing from the backscattered signals. It was found that the SAC method could be improved by employing singular value decomposition (SVD) to extract the effective rank for the spectral components. Unlike the conventional method of estimating the density of scatterers within the insonified volume of water, this type of estimation method would provide better understanding of the spatial distribution of scatterers in the ocean.