• Asian-Australasian Journal of Animal Sciences
• /
• v.9 no.5
• /
• pp.603-610
• /
• 1996

Spatial distribution of faeces by Japanese Black heifers and steers was investigated. The animals grazed a bahiagrass (Paspalum notatum $Fl\ddot{u}gge$) pasture in the daytime from 9 a.m. to 4 p.m., and spent the rest of the day in a barn. The pasture consisted of three paddocks, an alley and a resting area, and the paddocks were grazed rotationally. The number of defecations and the faecal weight excreted in the pasture were greater than those expected from the proportion of time that the animals spent in the pasture. These values were correspondingly smaller in the barn. The distribution of faeces to the paddock, alley and resting area of the pasture was usually not proportional to the area of the respective places. The number of defeations and the faecal weight were usually distributed less densely in the paddock than in the resting area. The degree of aggregation of defecation in the paddock, alley and resting area varied with the meteorological factors such as the air temperature, solar radiation and rainfall during the grazing, and the intake of hay supplement of the previous day.

• Asian-Australasian Journal of Animal Sciences
• /
• v.10 no.5
• /
• pp.484-490
• /
• 1997

Spatial distribution of urination by Japanese Black heifers and steers was investigated, and compared with the distribution of defecation. The animals grazed a bahiagrass (Paspalum notatum $Fl\ddot{u}gge$) pasture in the daytime, and spent the rest of the day in a barn. The distribution of urination to the pasture was greater than that expected from the proportion of time that the animals spent in the pasture. Correspondingly, the distribution was smaller in the barn. Such a distribution pattern of urination to the pasture and barn was similar to that of defecation, and affected by the intake of supplement on the previous day. The distribution of urination within the pasture, i.e. the distribution to the paddock, alley and resting area, was often uneven on an area basis. The animals often urinated sparsely in the alley and resting area, while they urinated in the paddock almost proportionally to its area. This was a clear contrast to the distribution pattern of defecation, which was sparse in the paddock and dense in the resting area. The degree of aggregation of urination in the paddock, alley and resting area varied with the meteorological factors and the intake of supplement.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.457-461
• /
• 2007

In many applications, received signal strength indicator is used for location tracking and sensor nodes localization. For location finding, the distances between sensor nodes can be estimated by converting received signal's power into distance using path loss prediction model. Many researches have done the analysis of power-distance relationship for radio channel characterization. In indoor environment, the general conclusion is the non-linear variation of RSSI values as distance varied linearly. This has been one of the difficulties for indoor localization. This paper presents works on indoor RSSI characterization based on statistical methods to find the overall trend of RSSI variation at different places and times within the same room From experiments, it has been shown that the variation of RSSI values can be determined by both spatial and temporal factors. This two factors are directly indicated by the two main parameters of path loss prediction model. The results show that all sensor nodes which are located at different places share the same characterization value for the temporal parameter whereas different values for the spatial parameters. Using this relationship, the characterization for location estimation can be more efficient and accurate.

• Ocean and Polar Research
• /
• v.39 no.2
• /
• pp.73-84
• /
• 2017

The probability distribution of ichthyoplankton is important for enhancing the precision of sampling while reducing unnecessary surveys. To estimate the ichthyoplankton detection proportion (IDP) and its margin of error (ME), the monitoring information of the chub mackerel's (Scomber japonicus) ichthyoplankton presence-absence sampling data has been were collected over approximately 30 years (from 1982 to 2011) in the Korean coastal seas. Based on the computed spatial distributions of the mackerel's IDP and ME, the confidence interval (CI) range, defined as 2 ME, decreases from approximately 80% to 40% as the sample size n increases from 4 to 24 and the ME is approximately 40% in the typical (seasonal survey) case n = 4 per year. The IDP and ME off Jeju Island are relatively high at the 0.5-degree smoothing level. After increasing the spatial smoothing level to 1.0-degree, the ME decreased, and the spatial distribution pattern also changed due to the over-smoothing effects. In this study, the 0.5-degree smoothing is more suitable for the distribution pattern than the 1.0-degree smoothing level. The area of the high IDP and the low ME on the mackerel's ichthyoplankton was similar to the estimated spawning ground in the Korean peninsula. This information could contribute to enhancing for the spawning ecology surveys.

• Water Engineering Research
• /
• v.3 no.1
• /
• pp.31-44
• /
• 2002

The effect of diurnal cycle, intermittent visit of observation satellite, sensor installation, partial coverage of remote sensing, heterogeneity of soil properties and precipitation to the soil moisture estimation error were analyzed to present the global sampling strategy of soil moisture. Three models, the theoretical soil moisture model, WGR model proposed Waymire of at. (1984) to generate rainfall, and Turning Band Method to generate two dimensional soil porosity, active soil depth and loss coefficient field were used to construct sufficient two-dimensional soil moisture data based on different scenarios. The sampling error is dominated by sampling interval and design scheme. The effect of heterogeneity of soil properties and rainfall to sampling error is smaller than that of temporal gap and spatial gap. Selecting a small sampling interval can dramatically reduce the sampling error generated by other factors such as heterogeneity of rainfall, soil properties, topography, and climatic conditions. If the annual mean of coverage portion is about 90%, the effect of partial coverage to sampling error can be disregarded. The water retention capacity of fields is very important in the sampling error. The smaller the water retention capacity of the field (small soil porosity and thin active soil depth), the greater the sampling error. These results indicate that the sampling error is very sensitive to water retention capacity. Block random installation gets more accurate data than random installation of soil moisture gages. The Walnut Gulch soil moisture data show that the diurnal variation of soil moisture causes sampling error between 1 and 4 % in daily estimation.

• Korean Journal of Acupuncture
• /
• v.36 no.4
• /
• pp.292-299
• /
• 2019

Objectives : DongUiBoGam is one of the representative medical literatures in Korea. We used text mining methods and analyzed the characteristics of the indications of each meridian in the second chapter of DongUiBoGam, WaeHyeong, which addresses external body elements. We also visualized the relationships between the meridians and the disease sites. Methods : Using the term frequency-inverse document frequency (TF-IDF) method, we quantified values regarding the indications of each meridian according to the frequency of the occurrences of 14 meridians and 14 disease sites. The spatial patterns of the indications of each meridian were visualized on a human body template according to the TF-IDF values. Using hierarchical clustering methods, twelve meridians were clustered into four groups based on the TF-IDF distributions of each meridian. Results : TF-IDF values of each meridian showed different constellation patterns at different disease sites. The spatial patterns of the indications of each meridian were similar to the route of the corresponding meridian. Conclusions : The present study identified spatial patterns between meridians and disease sites. These findings suggest that the constellations of the indications of meridians are primarily associated with the lines of the meridian system. We strongly believe that these findings will further the current understanding of indications of acupoints and meridians.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.2A
• /
• pp.121-129
• /
• 2008

This paper presents the spatial multiplexing MIMO system to increase data rate to double in MB-OFDM UWB system, which is ECMA standards, and compares BER performance of various receiver structures. The complexity and BER performance of various types of spatial multiplexing receivers are compared and analyzed using diagonal and horizontal encoding techniques for $2{\times}2$\;and\;2{\times}3$ antennas systems. Computer simulations exhibit that $2{\times}2$ MML and $2{\times}3$ ZF method show better BER performance than that of SISO system with simple complexity.

• The Journal of the Convergence on Culture Technology
• /
• v.6 no.1
• /
• pp.485-488
• /
• 2020

In this paper, a technique for securely concealing the watermark, which is intellectual property information, in the image pixel LSB using spatial encryption is proposed. The proposed watermarking technique can be effectively used to protect intellectual property of images. The proposed technique can be used to extract watermark without loss from the stego-image, which is a hidden image of spatially encrypted watermark. The experimental results confirmed the superiority of the proposed technique. As a result of performing watermarking using the proposed technique, the image quality of the stego-image is higher than 51 dB, so humans cannot visually recognize the presence of a watermark. Due to the watermark is spatially encrypted, the security of the watermark is excellent.

• Journal of Environmental Science International
• /
• v.27 no.7
• /
• pp.509-518
• /
• 2018

Weather is the most influential factor for crop cultivation. Weather information for cultivated areas is necessary for growth and production forecasting of agricultural crops. However, there are limitations in the meteorological observations in cultivated areas because weather equipment is not installed. This study tested methods of predicting the daily mean temperature in onion fields using geostatistical models. Three models were considered: inverse distance weight method, generalized additive model, and Bayesian spatial linear model. Data were collected from the AWS (automatic weather system), ASOS (automated synoptic observing system), and an agricultural weather station between 2013 and 2016. To evaluate the prediction performance, data from AWS and ASOS were used as the modeling data, and data from the agricultural weather station were used as the validation data. It was found that the Bayesian spatial linear regression performed better than other models. Consequently, high-resolution maps of the daily mean temperature of Jeonnam were generated using all observed weather information.

• The Korean Journal of Applied Statistics
• /
• v.20 no.3
• /
• pp.459-473
• /
• 2007

In this paper, we suggest a spatial regression model to predict AADT. Although Euclidian distances between one monitoring site and its neighboring sites were usually used in the many analysis, we consider the shortest travel path between monitoring sites to predict AADT for unmonitoring site using spatial regression model. We used universal Kriging method for prediction and found that the overall predictive capability of the spatial regression model based on shortest travel path is better than that of the model based on multiple regression by cross validation.