Outermost Points Research Articles

Seasonal variation of home range size and habitat selection of elephants in the Kabompo landscape of Zambia

BackgroundMovements of large herbivores and habitat utilization provide critical information for ecological monitoring and conservation. However, such geospatial information rarely exists, especially in sub-Saharan Africa. This study aims to provide insight on seasonal variation of home range size and habitat utilization by African savanna elephants (Loxodonta africana) in Zambia’s Kabompo Landscape.MethodsTwo male sub-adult elephants (estimated age 10–15 years) were collared and monitored between March 2018 and December 2021 using the Geographic Position System (GPS) tracking devices. We used Minimum Convex Polygon (MCP), which uses the outermost points, to arrive at the largest home range of a study subject and the Kernel Density Estimator (KDE), which captures the intensity use of various parts of the home range. Distance from the river, elevation, slope, land cover type, fire intensity and Normalized Difference Vegetation Index (NDVI) were assessed against habitat selection by elephants using multinomial logistic regression.ResultsThe findings showed that the movements of the elephants were largely confined within the West Lunga National Park. The wet season had the largest home range (1720.8 km2) dominated by grassland, while the cold dry season had the smallest area of 931.8 km2. Elevation and land cover types had significant (p-value < 0.05) influence on home range across all the seasons. Other factors also had positive and negative impacts on the home range selection depending on the season.ConclusionsThe insights from this study can be exemplary relevant to conservation planning through monitoring seasonal movement of elephants.

Fast, Nondestructive and Precise Biomass Measurements Are Possible Using Lidar-Based Convex Hull and Voxelization Algorithms

Light detection and ranging (lidar) scanning tools are available that can make rapid digital estimations of biomass. Voxelization and convex hull are two algorithms used to calculate the volume of the scanned plant canopy, which is correlated with biomass, often the primary trait of interest. Voxelization splits the scans into regular-sized cubes, or voxels, whereas the convex hull algorithm creates a polygon mesh around the outermost points of the point cloud and calculates the volume within that mesh. In this study, digital estimates of biomass were correlated against hand-harvested biomass for field-grown corn, broom corn, and energy sorghum. Voxelization (r = 0.92) and convex hull (r = 0.95) both correlated well with plant dry biomass. Lidar data were also collected in a large breeding trial with nearly 900 genotypes of energy sorghum. In contrast to the manual harvest studies, digital biomass estimations correlated poorly with yield collected from a forage harvester for both voxel count (r = 0.32) and convex hull volume (r = 0.39). However, further analysis showed that the coefficient of variation (CV, a measure of variability) for harvester-based estimates of biomass was greater than the CV of the voxel and convex-hull-based biomass estimates, indicating that poor correlation was due to harvester imprecision, not digital estimations. Overall, results indicate that the lidar-based digital biomass estimates presented here are comparable or more precise than current approaches.

GEODETIC RESEARCH OF THE SMOKESTACK TILT OF THE BOILER HOUSE ON KARNAUKHOVA STREET IN RIVNE

Smokestackеs are extraordinary and technologically important construction structures. Their safe operation is a prerequisite for long-term and trouble-free operation of a boiler house and the provision of heat to entire city districts. The purpose of this paper is to study the smokestack tilt of a boiler house using geodetic methods. The relevance of this research is in the fact that the smokestack tilt a dangerous factor that can lead to its destruction due to loss of stability or due to the force exceeding the maximum resistance. The destruction of such a structure can cause significant economic or even human losses.&#x0D; A preliminary calculation of the accuracy of geodetic work to determine the smokestack's tilt on M. Karnaukhova Street was performed. Based on the calculation results, an electronic total station Leica TCR 1205 was selected. A modified coordinate method was used to determine the position of a large number of points on the outer surface of the smokestack for each horizontal section. The measurement results are balanced by the parametric method of the least squares method. This method is implemented in the "Kren" software module developed by the authors.&#x0D; Three measurement cycles were performed in 2021, 2022, and 2023. The value of the tilt (about 200 mm) is quite noticeable for this smokestack with a bottom section diameter of 3.65 m. The smokestack is tilted in the direction from which the mobile communication equipment is installed. The balanced tilt value differs from the value calculated from the outermost observation points from the station. Tilt monitoring data should be considered as an integral part of the chimney building information system (BIM).

Is There a Relationship Between Vertical Facial Development And Nasal Cavity?

There are no studies investigating the relationship between cone beam computed tomography (CBCT) and nasal passage findings and vertical facial development. The aim of this study is to determine the relationship between nasal cavity anatomy and vertical development of patients. A total of 60 CBCTs were examined, and Class I malocclusion individuals were divided into two groups (30 each) according to vertical facial development. All nasal cavity findings were recorded in the study. Vertical facial development, nasal septum, nasal cavity width, thickness and angle were evaluated. Mann-Whitney U Test was used, and Student's t test was used for the comparison of two groups with normal distribution. Significance was evaluated at p<0.01 and p<0.05 levels. Statistical analysis showed a relationship between vertical facial development and nasal cavity findings. Nasal septum deviation was mild to moderate in the hyperdivergent group, while septal deviation was absent in the hypodivergent group. A statistically significant difference was found in the width, distance (x-y) and angle of the nasal cavity from the hyperdivergent group in Class I vertical subgroups (p<0.05). When compared between low-angle and high-angle groups, statistically significant differences were observed in anterior face height, nasal passage angle, and distance between the outermost points of the nasal cavity.

A Reliable Method for Determining the Degree of Orientation of Fibrous Foods Using Laser Transmission and Computer Vision.

The degree of organised alignment of fibre structures, referred to as the degree of orientation, significantly influences the textural properties and consumer acceptance of fibrous foods. To develop a new method to quantitatively characterise the fibre structure of such foods, a laser transmission imaging system is constructed to capture the laser beam spot on a sample, and the resulting image undergoes a series of image processing steps that use computer vision to translate the light and dark variations of the original images into distinct ellipses. The results show that the degree of orientation can be reasonably calculated from the ellipse obtained by fitting the outermost isopixel points. To validate the reliability of the newly developed method, we determine the degree of orientation of typical fibrous foods (extruded beef jerky, pork jerky, chicken jerky, and duck jerky). The ranking of the measured orientation agrees with the results of pseudocolour maps and micrographs, confirming the ability of the method to distinguish different fibrous foods. Furthermore, the relatively small coefficients of variation and the strong positive correlation between the degree of organisation and the degree of orientation confirm the reliability of this newly developed method.

A Recursive Hull and Signal-Based Building Footprint Generation from Airborne LiDAR Data

Automatically generating a building footprint from an airborne LiDAR point cloud is an active research topic because of its widespread usage in numerous applications. This paper presents an efficient and automated workflow for generating building footprints from pre-classified LiDAR data. In this workflow, LiDAR points that belong to the building category are first segmented into multiple clusters by applying the grid-based DBSCAN clustering algorithm. Each cluster contains the points of an individual building. Then, the outermost points of each building are extracted, on which the recursive convex hull algorithm is applied to generate the initial outline of each building. Since LiDAR points are irregularly distributed, the initial building outline contains irregular zig-zag shapes. In order to achieve a regularized building footprint that is close to the true building boundary, a signal-based regularization algorithm is developed. The initial outline is first transformed into a signal, which can reveal the wholistic geometric structure of the building outline after applying a denoising procedure. By analyzing the denoised signal, the locations of corners are identified, and the regularized building footprint is generated. The performance of the proposed workflow is tested and evaluated using two datasets that have different point densities and building types. The qualitative assessment reveals that the proposed workflow has a satisfying performance in generating building footprints even for building with complex structures. The quantitative assessment compares the performance of signal-based regularization with existing regularization methods using the 149 buildings contained in the test dataset. The experimental result shows the proposed method has achieved superior results based on a number of commonly used accuracy metrics.

Blind frequency offset estimation using the optimal decision threshold-assisted QPSK-partition method for probabilistically shaped MQAM systems.

Moderate or strong shaping conditions reduce the occurrence probability of the outermost ring constellation points of probabilistically shaped (PS)-M quadrature amplitude modulation (QAM) signals, which easily causes the peaks in the 4th power periodogram of received signals be submerged, accordingly the classical frequency offset estimation (FOE) scheme using 4th power fast Fourier transform (FFT) cannot be applied in PS-MQAM system. To solve this issue, we have proposed an optimal decision threshold assisted quadrature phase shift keying (QPSK)-partition blind FOE scheme. Firstly, the proposed scheme utilizes an optimal decision threshold assisted method for the symbol decision of received symbols, then chooses the symbols on multiple specific QPSK-shape rings. Secondly, the amplitude of each symbol selected above is normalized and uniformly augmented to 18. Finally, it carries out FOE using an improved time-domain 4th power feedforward method that eliminates the time interval. The effectiveness of the proposed scheme has been verified by 28 GBaud polarization division multiplexing (PDM) PS-16/64QAM simulations and 28/8 GBaud PS-16/64QAM experiments. The results obtained by this scheme present that under moderate or strong shaping conditions, the generalized mutual information (GMI) increases with optical signal-to-noise ratio (OSNR) and eventually exceeds the corresponding GMI threshold. Besides that, the FOE range can reach [-Rs/8, Rs/8], where Rs denotes the baud rate. When OSNRs are higher than 16 dB and 19.5 dB, the NMSEs of PS-16QAM-3/3.6 are lower than 1e-7, respectively. For PS-64QAM-4.4/5, the NMSEs achieve lower than 1e-6 after OSNR increases to 20.3 dB and 23.4 dB, respectively. More importantly, the overall complexity can be reduced to O(N), which is at most as 26.5% as that of FFT FOE scheme.

Maritime Security Dynamics of Archipelagic States with Focus on Maldives

Archipelagic waters are created when an archipelagic state meeting the qualifications of article 47 of the Law of the Sea (LOS) convention draws archipelagic baselines joining the outermost points of the outermost islands and drying reefs of the archipelago. Maldives is an archipelagic state with 99.7% of the area is sea situated in the birthplace of maritime civilization- the Indian Ocean. In recent years, Maldives has seen a growing inclination towards its maritime environment with the expanding economy fuelled by growing international tourism, shipping, overseas trade and fisheries. Owing to the strategic position of the country and its proximity to vital Sea Line of Communication (SLOC) that are infested with rising threats and crimes. Though Maldives does not have any territorial disputes with neighboring countries, country is facing great challenges in dealing with narcotics, ERF and other non- traditional maritime threats especially environmental challenges. Maldives is facing various threats for her existence other than the issues faced due to climate changes. To deal with these challenges Maldives maritime agencies need to be conceptualized, instead of Marine Police under the Maldives Police Service, and other government institutions such as Customs Marine Department under Maldives Customs Service and Immigration Marine Department under Maldives Immigration working independently. Maldives Maritime Authority can be formed to work under one umbrella to oversee functions of the above mentioned departments. Hence law enforcement at sea will be more effective, economizing the effort and resources while serving the people effectively to deter future threats and uncertainty.

Indonesia’s Archipelagic State Status: Current Development

A crucial, almost revolutionary, development in the international law of the sea was the recognition of archipelagic state principles within the United Nations Convention on the Law of the Sea 1982 (LOSC). The essential features of archipelagic state principle laid down by Part IV of LOSC include permission to draw straight archipelagic baselines around the outermost points of the outermost islands of archipelagos; and the recognition of the new and distinct legal regime of archipelagic water for the waters thus enclosed of a nature designed to accommodate the interests of maritime user states, that are states which carry out certain activities, including navigation, in the water areas falling under the jurisdiction of archipelagic states. Since this principle has been Indonesian national philosophical outlook even before the adoption of LOSC and provided within Article 25 (a) of the Indonesian Constitutions, it is submitted that all Indonesian national legislations related to ocean affairs should be based on the archipelagic state principles. This study looks at the legal application of archipelagic state principles in Indonesia within the framework of contemporary ocean governance principles. This paper argued that current development on Indonesian law of the sea as well as ocean governance shows less commitment to archipelagic state principles. Thus, it is submitted that archipelagic state principles should be re-stored as the basis of all ocean related legislations and governance.

Bi-Directional OFDM Truncated PS-4096QAM Signals Transmission in a Full-Duplex MMW-RoF System at E-Band

A bi-directional photonics-aided millimeter-wave (MMW) transmission system at E-band is proposed in this article, which can be applied in future mobile networks. Only one pair of horn antennas are adopted in the experiment to support symmetrical wireless signal transmission. The center frequency of the downlink and uplink is set as 73.5 and 83.5 GHz, respectively, to avoid the interference effect. Moreover, the probabilistic shaping (PS) technique is used to adapt transmission rate and improve system capacity under a limited SNR. The time-domain Volterra series based equalizer effectively compensates the nonlinear distortion induced by the photoelectric devices. Based on the experimental results, the proposed full-duplex MMW-RoF system can support OFDM truncated PS (TPS)-4096QAM signal transmission, whose entropy is 10 bits/symbol/Hz. We set the probability of the outermost points to zero and the generated TPS-4096QAM signal is actually a PS-1936QAM one. The system simultaneously allows 7 Gbaud TPS-4096QAM signal downlink and uplink transmission over 2 m wireless distance, satisfying the NGMI threshold at 0.83. Moreover, the bi-directional 7 Gbaud PS-1024QAM signal transmission distance can be extended to 13.4 m when we adopt a higher NGMI threshold at 0.67. So the total rate of our proposed bi-directional transmission system is achieved to 100 Gbit/s. We also investigate the BER performance with different modulation formats. Such a system is a promising solution for future high-speed backhaul networks with multiple modulation format requirements.

Возрастные изменения головного указателя и размеров таламусов у мезоцефалов

Objective: to identify the pattern of age-related changes in the cerebral index and to determine the dynamics of trans-verse and longitudinal thalamic dimensions in mesocephalians according to magnetic resonance imaging. Material and methods. The data of magnetic resonance imaging of the brain of 78 people (37 men and 41 women) were analyzed. Depending on the age, all the subjects were divided into two groups. Group I consisted of 43 people (21 men and 22 women) of the first period of adulthood (29.19±0.73 years), group II - 35 people (16 men and 19 women) of senile age (78.97 ± 0.61 years). The cranial width index and cranial length index were calculated from the outermost protruding points on the axial section in 3D reconstruction mode. Morphometric examination of the thalamus included determining its linear dimensions in the axial plane: transverse (distances from the most distant medial and lateral points) and longitudinal (distances from the most distant anterior and posterior points). Results. Analysis of head index values revealed their statistically significant prevalence in men compared to women in the first period of adulthood (p&lt;0.01). In old age, there were no sex differences, but there was a tendency for the values of the head index to prevail in men compared to women (p&gt;0.05). Transverse and longitudinal dimensions of the thalamus in both hemispheres were found to be predominant in both males and females in the first period of adulthood in comparison with old age (p&lt;0,01). When comparing the thalamic dimensions of the right and left hemispheres, both in the first period of adulthood and in senile age, no statistically significant differences in parameters were found, but there was a tendency for their predominance in the left thalamus (p&gt;0.05). Conclusion. The results obtained in this study add to the information available in the scientific literature on age-related changes in the cerebral index as well as on the morphometric characteristics of the thalamus in both sexes during the first period of adulthood and in old age, making it possible to implement a personified approach in medical practice as well as to use these data in further clinical and basic research.

Annular Neighboring Points Distribution Analysis: A Novel PLS Stem Point Cloud Preprocessing Algorithm for DBH Estimation

Personal laser scanning (PLS) has significant potential for estimating the in-situ diameter of breast height (DBH) with high efficiency and precision, which improves the understanding of forest structure and aids in building carbon cycle models in the big data era. PLS collects more complete stem point cloud data compared with the present laser scanning technology. However, there is still no significant advantage of DBH estimation accuracy. Because the error caused by merging different point cloud fragments has not yet been eliminated, overlapping and inaccurate co-registered point cloud fragments are often inevitable, which are usually the leading error sources of PLS-based DBH estimation. In this study, a novel pre-processing algorithm named annular neighboring points distribution analysis (ANPDA) was developed to improve PLS-based DBH estimation accuracy. To reduce the impact of inaccurately co-registered point cloud fragments, ANPDA identified outliers through iterative removal of outermost points and analyzing the distribution of annular neighboring points. Six plots containing 247 trees under different forest conditions were selected to evaluate the ANPDA. Results showed that in the six plots, error reductions of 53.80–87.13% for bias, 38.82–57.30% for mean absolute error (MAE), and 27.17–56.02% for root mean squared error (RMSE) were achieved after applying ANPDA. These results confirmed that ANPDA was generally effective for improving PLS-based DBH estimation accuracy. It appeared that ANPDA could be conveniently fused with an automatic PLS-based DBH estimation process as a preprocessing algorithm. Furthermore, it has the potential to predict and warn operators of potential large errors during hierarchical semi-automatic DBH estimation.

A basic end-member model algorithm for grain-size data of marine sediments

End-member (EM) unmixing algorithms are widely used in the earth sciences for unmixing compositional data such as grain-size data of sediments. However, many unmixing algorithms only use goodness-of-fit measures that justify the EMs in the absence of geological feasibility, and others tend to find EMs that enclose the sample points as tightly as possible, resulting in the calculated EMs are still mixed products, especially when unmixing highly mixed dataset. This paper proposes that EM unmixing algorithms should search for the Basic-EMs, i.e., the outermost points in the EM space. The EMs that can be unmixed by mathematics can also be purified by physical processes, i.e., the actual EMs are most likely the Basic-EMs. This paper also introduces a basic end-member model algorithm (BasEMMA) that uses genetic algorithms which mimic natural evolution processes, to seek the Basic-EMs. The evaluations by BasEMMA using both artificial and actual grain-size data show that BasEMMA can accurately find the Basic-EMs. This paper also introduces a procedure for determining the appropriate EM number, which has plagued previous researchers. In summary, this paper introduces a new way to determine geologically feasible EMs, a new EM unmixing algorithm and a new method to determine the appropriate EM number.

Loading path optimization of shaft clinching forming assembly using finite element simulation and response surface methodology

Shaft clinching forming assembly has become a mainstream clamping technology of wheel bearings. The radial deformation of inner rings is the main negative impact in the shaft clinching forming process. The elastoplastic finite element method was used to study the shaft clinching forming process of wheel bearings, and the accuracy of the numerical simulation was verified by experiment. The ratio of the inner ring outside diameter variation to the clamping force ( RIC) was taken as an optimization objective. Response surface methodology was used to optimize the loading path of punches in the shaft clinching forming process. Three factors were selected, including the central angle between two successively appeared outermost points of the plum blossom shape loading trajectory ( θ), the rotation speed of the punch ( ω), and the tilted angle of punches ( α). The results show that the central angle θ is the most sensitive factor, and the interaction effects of the central angle θ and the speed of autorotation ω on the ratio RIC are the most significant. Finally, the minimum ratio RIC and a corresponding loading path are obtained. The research results can be applied to other rotary forging processes.

Liquid distributor design for random packed columns

Liquid distributors are the second most important internal in packed columns, as they ensure sufficient initial distribution, which is crucial to achieve optimum separation performance. In this work, a liquid distributor design method is presented, which applies the TUM–WelChem Cell Model to consider the interaction between the liquid distributor and the packing. Liquid distribution in the packing is estimated in dependence of the liquid distributor design. An overall maldistribution quality is determined as a characteristic value for evaluation. Two common methods, the coefficient of variation and the liquid distribution quality by Moore and Rukovena, are implemented for reference. A parameter study with an exemplary column design provides optimum drip point densities for different types of packing. Moreover, the spacing between the outermost drip points and the column wall is considered in detail, suggesting an optimum distribution quality for high wall spacing. Further application of the method suggests an increase of the optimum drip point density for smaller column diameters. Application of the TUM–WelChem Cell Model to liquid distributor design provides a potent tool for an optimized distributor layout with sufficient initial distribution at minimized material usage and high free space for the gas flow.

Exact solution to a Liouville equation with Stuart vortex distribution on the surface of a torus

A steady solution of the incompressible Euler equation on a toroidal surface of major radius R and minor radius r is provided. Its streamfunction is represented by an exact solution to the modified Liouville equation, , where and κ denote the Laplace–Beltrami operator and the Gauss curvature of the toroidal surface respectively, and c, d are real parameters with cd < 0. This is a generalization of the flows with smooth vorticity distributions owing to Stuart (Stuart 1967 J. Fluid Mech. 29, 417–440. (doi:10.1017/S0022112067000941)) in the plane and Crowdy (Crowdy 2004 J. Fluid Mech. 498, 381–402. (doi:10.1017/S0022112003007043)) on the spherical surface. The flow consists of two point vortices at the innermost and the outermost points of the toroidal surface on the same line of a longitude, and a smooth vorticity distribution centred at their antipodal position. Since the surface of a torus has non-constant curvature and a handle structure that are different geometric features from the plane and the spherical surface, we focus on how these geometric properties of the torus affect the topological flow structures along with the change of the aspect ratio α = R/r. A comparison with the Stuart vortex on the flat torus is also made.

Detection Schemes for High Order $M$ -Ary QAM Under Transmit Nonlinearities

Nonlinearities in various stages of a transmitter may hinder and restrict the transmission rate. As observed in many studies, outermost constellation points are usually more adversely affected by these impairments. To observe these effects, we utilize two power amplifier models that have different effects on transmitted signals. The Rapp model considers only amplitude deformation and the resultant in-phase and quadrature errors can be assumed to be independent on the receiver side. Unlike the Rapp model, the Saleh model exerts both amplitude and phase deformations and the phase deformation introduces correlation between the in-phase and quadrature errors according to our observations. In addition to the correlation, the variances of in-phase and quadrature errors may not be equal to each other. In this paper, we propose receivers that consider error variances of each quadrature amplitude modulation (QAM) symbol. We compare the performances of the receivers with those of other receivers that take average error variances into account for decoding. Furthermore, we propose a practical receiver that directly works on digitized observations based on a look-up table that keeps log-likelihood ratios of the quantized regions in order to reduce computational complexity.

Consistency assessment of rating curve data in various locations using Bidirectional Reach (BReach)

Abstract. When estimating discharges through rating curves, temporal data consistency is a critical issue. In this research, consistency in stage–discharge data is investigated using a methodology called Bidirectional Reach (BReach), which departs from a (in operational hydrology) commonly used definition of consistency. A period is considered to be consistent if no consecutive and systematic deviations from a current situation occur that exceed observational uncertainty. Therefore, the capability of a rating curve model to describe a subset of the (chronologically sorted) data is assessed in each observation by indicating the outermost data points for which the rating curve model behaves satisfactorily. These points are called the maximum left or right reach, depending on the direction of the investigation. This temporal reach should not be confused with a spatial reach (indicating a part of a river). Changes in these reaches throughout the data series indicate possible changes in data consistency and if not resolved could introduce additional errors and biases. In this research, various measurement stations in the UK, New Zealand and Belgium are selected based on their significant historical ratings information and their specific characteristics related to data consistency. For each country, regional information is maximally used to estimate observational uncertainty. Based on this uncertainty, a BReach analysis is performed and, subsequently, results are validated against available knowledge about the history and behavior of the site. For all investigated cases, the methodology provides results that appear to be consistent with this knowledge of historical changes and thus facilitates a reliable assessment of (in)consistent periods in stage–discharge measurements. This assessment is not only useful for the analysis and determination of discharge time series, but also to enhance applications based on these data (e.g., by informing hydrological and hydraulic model evaluation design about consistent time periods to analyze).

A study of interdependence of geometry of the nuchal neck triangle and cervical spine line in the habitual and straightened postures

IntroductionThe paper shows the mutual dependencies of height and angles of the neck triangle and selected points of the spine for straightened and habitual postures with the use of a non-contact optical tool. A group of 39 healthy, adult volunteers participated in the study, which was conducted in Warsaw, Poland. Results show relationships between the habitual posture in the sagittal plane, the angle of the triangle between the cervical and upper thoracic kyphosis and the vertical line defined by spine points C7/Th1. MethodsMeasurement system based on photogrammetry was used for spatial determination of specific points. Specially designed non-invasive markers were used. The presented paper shows a new approach for analysis of the geometry of the upper part of the human musculoskeletal system with the use of optical systems in biomedical applications. ResultsResults are presented as series of 14 defined parameters and calculated for habitual and straighten postures. Results were analyzed as a values of correlation coefficients and significance level. DiscussionAn analysis of measurements results based on a triangle represented by three points: two outermost points of the superior nuchal line of the skull and the C7 point are presented. This approach allow to characterize individual positioning of the head in space and is sensitive to many changes in the musculoskeletal system – i.e. the individual way of “standing up straight”.

급경사지 붕괴위험 판단을 위한 강우기반의 한계영역 설정 기법 연구

Rainfall-induced landslide disaster case histories are typically required to establish critical lines based on the decrease coefficient for judging the likelihood of slope collapse or failure; however, reliably setting critical lines is difficult because the number of nationwide disaster case histories is insufficient and not well distributed across the region. In this study, we propose a method for setting the critical area to judge the risk of slope collapse without disaster case history information. Past 10 years rainfall data based on decrease coefficient are plotted as points, and a reference line is established by connecting the outermost points. When realtime working rainfall cross the reference line, warning system is operating and this system can be utilized nationwide through setting of reference line for each AWS (Automatic Weather Station). Warnings were effectively predicted at 10 of the sites, and warnings could have been issued 30 min prior to the landslide movement at eight of the sites. These results indicate a reliability of about 67%. To more fully utilize this model, it is necessary to establish nationwide rainfall databases and conduct further studies to develop regional critical areas for landslide disaster prevention.