Due to their wide applicability in inspection of concrete structures, there is considerable interest in the development of automated crack detection method by image processing. However, these methods are not yet accurate enough due to the difficulty and complexity of the problem. Authors consider that further detection methods and knowledge should be accumulated to make it accurate and practical. This paper proposes automated crack detection method based on random forest which is one of the supervised machine learning method. The accuracy of developed method is investigated by the photos of concrete structures with lots of adverse conditions including shadow and dirt, and it is found that the method can extract the crack region with high accuracy.

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 This paper proposes an electronic signboard using an UHF band RFID system for disaster management and its communication methods. RFID tags need no internal battery because a voltage source is generated by an incoming electromagnetic wave. Therefore, an RFID based communication method is appropriate in the case of losing electrical infrastructure due to a disaster. An RFID array structure enhances memory capacity to store a lot of characters in an internal memory of an RFID tag. To identify individual RFID tags and write data to the intended one, a function to recognize an identification number stored in an internal memory is embedded to reader/writer software. Furthermore, this array structure can also enhance communication distance in conjunction with the use of a reflector. Prototypes demonstrate validity of the proposed system.

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 Vegetation distribution in urban areas has previously been investigated through image classification and interpretation techniques using satellite images. However, vegetation distribution and density within cities have not been extensively studied using the imagery from satellites WorldView-3 and WorldView-2 having a high resolution of 30 cm. In this study, to evaluate the distribution of trees and lawns in a city park in Tokyo, the object-oriented technique for the classification of images with different spatial resolutions was compared with the pixel-based technique. The results of comparative study showed the KNN method for the images obtained by the WorldView-3 satellite to be the most effective. In addition, the possibility of creating vegetation distribution maps for urban parks using these features was considered.

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 Civil engineering structures are build-to-order manufacturing single items, which differ considerably from products such as household appliances or cell-phone sin the characteristic that their service life is over 50 years. However, in recent years image wearing is becoming a common necessary requirement in both cases. In the present research, girder bridges which represents the great majority of the constructed bridges were considered to investigate which characteristics a bridge must have to be considered as not-wearisome by applying rough sets. The study subjects were bridge engineers, male and female students. In rough sets the decision rule is the most applied and uses the C.I. (Covering Index) as an index that represents the degree of contribution of each element of the rule condition part to the conclusions in the decision chart. Not-wearisome design elements or wearisome design elements are considered based on C.I. values.

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 Development of traffic flow monitoring technology is required at areas where are not enough equipped traffic sensor infrastructure such as Asian countries and rural cities in Japan. Data collection from vehicles having smart phone and car navigation system has attracted attention to be one of the solution for those issues since these devices are installed Bluetooth devices that has unique MAC address, and matching of MAC address can collect traffic state data such as travel time, OD traffic volume and so on. However details of characteristics of MAC address data detection have not yet known to use for traffic state analysis. Therefore this research analyzes MAC address data detection rate from Bluetooth devices focusing on the distance and angle between MAC address scanner and transmitters. In addition, difference of setting way (horizontally and vertically placed) of MAC address scanner is also considered to analyze MAC address detection rate. Experiment results shows detection rate changed by distance, angle and setting way of MAC address scanner, and detection rate is significantly different by difference of those factors. Therefore hypothesis of this study what MAC address scanner has directivity to detect MAC address from Bluetooth devices has been supported statistically. And its results also showed importance of considering directivity for data collection from vehicles installing Bluetooth devices.

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 The objective of this study is to develop the learning system of the evacuation behavior in the disaster such as tsunamis, using the serial images taken by MMS ( Mobile Mapping System) as well as the maps. The all-around view camera, angle meter and GPS antenna are mounted on the moving object such as the car in MMS.
 The evacuation route can be shown in the serial images through the streets as well as in the map by synchronizing the pictures in the serial images with the time-series data of the location of an evacuee. It enables the realistic visualization of the results of the evacuation simulation. Moreover, this system helps the identification of the hazards which may be hard to be noticed, since the measurements of such as the width of the streets and the height of the possibly collapsing walls can be performed through the video.

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 Introduction consideration of a CIM is accomplished as utilization of IT to a construction production process (ICT) in our country in recent years. As a result data profit utilization of three-dimensional model of the construction field has started. The three-dimensional model to which attribute information was given is to be utilized in a construction life cycle, and improvement of the productivity of the whole construction business is expected. For the moment, I design at both of three dimensions and two dimensions. Therefore designer's work rate isn't reduced. This study will report the result which considered a drawing of the usual method and the way to calculate the quantity from a 3D model.

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 In this study, we apply the serious game for pre-training of assumed evacuation a disaster. In the development of the game, after extracting three elements that include goal, interaction and quantization as a feature element of serious games, the evacuation game was developed with three stages allocate these elements. Then, the experiment was conducted to compare the learning effect between game-based learning and text-based learning. As a result, it became clear that it can learn fun in game-based learning although the learning effect is slightly inferior compared to the text-based learning., and game-based learning is likely to get more learning outcomes than the text-based learning by adding more game elements.

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 Numerous developed countries are currently facing problems resulting from the aging of decades-old infra-structures built during periods of rapid economic growth. Additionally, under prevailing severe fiscal circumstances found in many aging societies, it is not realistic to deal with every failing infrastructure facility in every part of a country. This paper focuses on pipelines for water supply, sewerage, and agricultural water use, many of which are buried, which makes investigating their distortion and deterioration difficult without excavation. Under such conditions, maintenance work proceeds slowly and failing buried pipes eventually rupture, which frequently inconvenience citizens and damage property. The authors have been proposing an investigation system that utilizes an RGB-D camera, or a depth-imaging device to examine pipeline interiors. RGB-D cameras can collect not only the RGB-color imagery, but also three-dimensional (3D) depth information from pipe interiors. Taking advantage of the com-pact size of RGB-D cameras, our proposed concept is based on the construction of a self-propelled robot system that will scan pipeline interiors in-situ, thus providing a means of conducting fast and inexpensive investigations that do not require large-scale excavations. This paper describes a novel method that can be used to detect deflection in pipe-shaped structures directly based on depth image capturing with a RGB-D camera. In order to settle intersection planes for deflection examination, the key idea is to find the longitudinal direction from the captured depth images based on the normal vector information, even in the cases that captured 3D point distribution does not form an entire piped-shape. This paper also shows that, based on a prototype implementation using a Kinect camera, the proposed method shows effective performances for actual point cloud data with light computational costs.

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 Recently, CIM (Construction Information Modeling/Management) is being introduced to civil engineering industry inside Japan. Among civil structures, CIM is also introduced in several river projects. However, case studies for River CIM are still small in number. River has floodway, which is always changing, unlike other civil structures. Therefore, maintenance phase is of much importance. Thus, the assistance of the project owner who maintains the structures is significant. In addition, river project has a lot of data which are accumulated until now. By introducing CIM, it can improve the efficiency of management work. In this paper, the authors have made River Management CIM Model using the existing data, such as a plan view and cross sectional views. By using this model, the authors have created a new method for management by using various types of visualization such as visualization of invisible parts, which is difficult to see in reality. Finally, the authors have applied the management model inside a case study to prove its usability.

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 In BIM for Infrastructure, a 3D product model of the bridge includes huge data which is created in its whole lifecycle. In order to share such a huge model between stakeholders and to use it efficiently, it should be managed by some DBMS (DataBase Management System). Relational DBMS is commonly used as an engine by many database systems, but we thought that the DBMS can't efficiently manage the model which is constructed with deep level structure. And we researched performance characteristics of several kinds of DBMS in which the model is stored. Finally we cleared which DBMS can efficiently manage 3D product models of the bridge.

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 Indoor walking support systems for the visually impaired have not been put to practical use because these systems usually need a lot of equipments on the site and there are administrative problems and operational issues. A self-position estimation technique was proposed that could be used in indoor walking support system for the visually im-paired without equipments on the site. It was shown that it was possible to estimate self-position by the proposal backward intersection method with the known position of the walls which are expressed by linear equations on the co-ordinated planes and the ranges to the walls that were measured by using four laser rangefinder.

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 This study was made to propose the method for extracting the positional information of the road structures required for au-tomatic running by giving the threshold of Reflection intensity value, RGB average value and altitude of 3D point cloud data. In case of extraction of white line, threshold values were discussed on Reflection intensity value and RGB average value. In the case of traffic light, has been done using Reflection intensity value and altitude, RGB average value and altitude. The determination of the threshold 3D point cloud data acquired on the 3 intersections by MMS. The verification of the method has been executed using 3D point cloud data another intersections by MMS. As a result, extraction rate of the object and the removal rate of unwanted substances became sufficient results.

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 This paper proposes a semiautomatic method for concrete surface cracks extraction from digital images. The characteristic feature of the method is the combination of interactive genetic algorithm (iGA) and touchscreen. The iGA is applied to optimize image processing parameters for each image without knowledge of image processing techniques. The touchscreen enables the user to touch images directly and extract cracks smoothly. Finally in order to show the capability of the software which implements the proposed method, concrete surface cracks are extracted from digital images with reasonable accuracy and processing time.

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 In the planning and construction stages of the structures, to prevent redo of the design and construction at a construction site, it is important to imagine and understand the shape and location of the structures to be constructed. If it is possible to visualize the construction situation of structures before construction, a more practical construction plan is possible. Hence, by applying augmented reality (AR) technology, we developed a system where the three-dimensional model design drawings are projected on motion pictures delivered from on-site monitoring cameras, and clarified the image of the structure in the construction-stage, and made it possible to visualize the scale. We mounted several functions for the purpose of doing use at a site of the various conditions.
 To show the practicality of this system, we examined it on actual planning and construction-stage sites. Field checking tests confirmed that positional relationship and scale of structures could be made clearer and that communication among stakeholders became smooth. Furthermore, by superimposing the local structure and design drawings, the obstacle for construction became clear. These results suggest that this system is very useful for actual planning work because the proposed method is effective in understanding construction plans before construction.

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 Ministry of Land, Infrastructure, Transport and Tourism (MLIT) in Japan is promoting the intelligent construction for productivity improvement, quality assurance, and cost reduction. In the intelligent construction, as-built management using Total Station (TS) is conducted. In this situation, a three-dimensional design data is manually created based on a two-dimensional drawing. And this puts a burden to contractors. Therefore, it is necessary to create a three-dimensional design data automatically. In order to solve this problem, there is a three-dimensional polyline utilized in Machine Control and Machine Guidance (MC/MG). This polyline data has the information required to create a three-dimensional design data. In addition, there are sites where MC/MG is combined with as-built management using TS. Therefore, if a three-dimensional design data is automatically created using a three-dimensional polyline, it could reduce the time and cost to create it.
 In this research, a system of generating three-dimensional design data based on three-dimensional polyline was developed. And we verified feasibility in the actual construction site.

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 The inspection of road tunnels are mainly conducted by visual inspection. Therefore, there is a need for the automation. The authors have developed an inspection vehicle for tunnel lining concrete. The vehicle takes continuously scanned images of tunnel wall by using digital video cameras. In this study, an automatic image stitching method is developed by image processing techniques in order to generate panoramic images of tunnel wall from the scanned images. Furthermore, application to an existing tunnel is presented so as to demonstrate the validity of the proposed method.

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 Smartphone easily enables to acquire a high accuracy location information using GPS sensor. Location information is expected to utilize in the field of disaster measures and traffic safety. For example, in a disaster, it is necessary for smartphone users to grasp a high accuracy three-dimensional location information. However, the three-dimensional location information measured by Global Positioning System on the individual smartphone includes many noises by reason of different environment and devises. It is possible that analysis of enormous amounts of probe data can handle the problem mentioned above. However, this is not satisfactory for the uses in emergency as the smartphone lacks real-time performance. In this research, a method for removing noises was proposed for acquiring high accuracy three-dimensional location information from a person trip survey of smartphone in real time.

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 This paper proposes a flexible technique framework for optimizing the scanning plans of outdoor constructions using photogrammetry-based modeling and mathematical optimization. Our framework is capable of accepting onsite feedbacks and flexibly reflecting them on the recalculation to complete the scanning through an optimized manner, thus the users can make the most use of the executed scans during the ongoing work. Based on a structure-from-motion (SFM) technique and a patch-based meshing technique, taking photos of the target site during a preliminary survey makes it possible to acquire three-dimensional (3D) point clouds and dense 3D surface meshes systematically. Such 3D information enables elaborate estimation of precise visible characteristics of the targeted scanning object from multiple different scanner viewpoints, so that a mathematical programming method can then be used to derive an optimal scan with the minimum number of measurement points and their layout necessary to scan all surfaces of the target object. On the hand, since on-site ground conditions at the planned scanner positions are sometimes unavailable when setting up the scanner, prepared plans may need to be modified or improved. The proposed optimization scenario can accept such modifications by editing the prepared 3D mesh models so as to fit the physical conditions. The proposed method was applied to an actual field of a castle ruin, where the stone walls need to be managed for conservation. A unmanned aerial vehicle (UAV) was used to collect photos for photogrammetry-based 3D modeling and initial optimization of the scanning plan, which needed to be modified to change the number of scans and a scanner position due to the ground conditions and requests from collaborating investigators on the spot. Eventually, the quality of the acquired point cloud was adequate for further investigations in terms of coverage and density with minimum scans.

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 The purpose of this research is to develop a consensus building system for an early restoration of road network after earthquake disasters. Restoration priority of the road network depends on restoration purposes. Therefore, road restoration works set a common goals and must effectively use the limited resources. However, because recovery purposes in each region organization may be different, it is difficult to build consensus among them. In this study, we develop web-based consensus building system based on an concept of district impact analysis. Several restruction schedule cases are presented to demonstrate the effectiveness of the proposed system.

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 In evaluating public works projects, it is necessary to evaluate their current condition quantitatively and qualitatively from diversified viewpoints based on the social situation. For the road projects, road traffic analysis is carried out to grasp the actual traffic condition quantitatively. If this analysis result reflects public opinions that are qualitative in detail, it can be expected that this will help to advance the evaluations of road projects. To collect qualitative public opinions, one of the effective measures is to utilize tweets from Twitter, which is a form of microblogs. However, since there are all sorts of tweets in circulation, it is difficult to appropriately extract the tweets that are useful in evaluating road projects. Moreover, even if a useful tweet is extracted, it is very hard to identify the location indicated by the tweet.Thus in this research, we devised a text mining method that combines road traffic data found on the Web with tweets from Twitter, and evaluated the feasibility of extracting public opinions related to road works projects and of estimating their locations.

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 This paper presents a visualization system based on augmented reality technology for environmental flow problem. The 2D marker-less method using a landscape image for the studied site is employed for the positioning method for the virtual image and real image. The present system is applied to the flow visualization for the air flow simulation around the building in urban area. The validity and applicability is investigated through the application examples. From the results, the present system is shown to be a useful tool for AR visualization of environmental flow simulation.

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 The Ministry of Land, Infrastructure and Transport has implemented the CIM pilot projects from 2012. The CIM at the phase of design and construction, the effect is exhibited. In the future, due to the aging of society's infrastructure, it is expected that the growing needs of maintenance. In the maintenance, the use of CIM is expected.
 In the present study, in order to take advantage of the CIM in the maintenance phase, it was examined how to create and attribute information of the three-dimensional model . We have proposed a method of creating a three-dimensional model . Its three-dimensional model is easier to use in an efficient and maintenance phase . To that end , we have defined the level of detail of the three-dimensional model of a element unit and take advantage of the scene and the set.

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 In the construction site of residential areas are in close proximity, because of the noise due to construction work, there is a case in which complaints may occur. And to experience in actually my ear the effect of noise measures, the purpose of that for you to understand, we have developed a VR (Virtual Reality) noise simulation system composed of tablet terminal (iPad) with headphones. VR noise simulation system, by making full use of multi-media functions of the tablet (iPad), actually listening to the noise in my ear, is that the noise reduction effect can VR(Virtual Reality) manner experience. For example, by utilizing this system, since the deeper understanding of each other is a communication tool, it is considered to sometimes become opportunity to think about construction. Moreover, the system, various soundproofing performance, the noise source, it is possible to register the background noise, a new system ever the tablet itself is a database of the noise.

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 Vegetation in urban areas has several functions such as the conservation of ecosystem, the reduction of urban heat island phenomenon, etc. The spatial continuity of vegetation distributions is required for the effective performance of the functions. In order to make locational planning of greenery areas, it is necessary to grasp the long-term change of the greenery areas. We have developed a spatial analysis method for detecting the continuity of vegetation distributions on a regional scale using remotely sensed data. The method consists of local spatial autocorrelation analysis, an overlay analysis, and a hydrological analysis with the Normalized Difference Vegetation Index (NDVI) adopted as the proxy of vegetation abundance. In this study, we apply the spatial analysis to two types of remotely sensed data acquired in 2000 and 2013, respectively. We discuss the long-term change of the spatial continuity of vegetation distributions through comparing between the results of the analysis. As a result, a change of the continuity of vegetation distributions were found to be involved in areas of large-scale urban development in study area.

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 A large-scale eruption occurred in Kagoshima, Kuchienorabu Island on May 29, 2015. This eruption released pyroclastic flow, which reached the shore areas. In this study, the disaster caused by this eruption was investigated using near real-time multi-spectral satellite images from Landsat-8/OLI, observed before and after the eruption, and ASTER/Global DEM data. These data were used for detailed image interpretation and three-dimensional indications of the extent of damage and the area covered by the pyroclastic flow. Furthermore, the characteristics of the distribution of damaged forest areas were obtained through NDVI analysis. From these investigations, the effectiveness of information from the near real-time remote sensing data in the evaluation of the volcanic disaster was assessed.

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 It is expected to improve the whole construction process by using the CIM(Construction Information Modeling/Management). Therefore, MLIT(Ministry of Land, Infrastructure, Transport and Tourism) has studied the introduction of the CIM, and has been attempted the CIM in several projects. In this paper, we reports the results of the trial for applying the CIM in the embankment project that is in the construction stage. Based on the results of the trial, we describe the effects of CIM in the construction stage, and we confirm that we can apply the CIM model to the Intelligent Construction.

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 The objective of this paper is to study on train operation disorde using official twitter of urban railway companies in the Tokyo metroporitan area. The frequency and causes of occurrence of the suspension of the train, the characteristics of the trouble time and error of operation resumption expected time were revealed by using the twitter information. As a result, it found that is more likely to occur suspension of the train service due to injury, the variation of trouble time in cause failure of facilities is greater, the error of the operation resumption expected time is within 15 minutes in the whole of 70%.

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 A Mobile Mapping System (MMS) can acquire three-dimensional position data around a vehicle. However, MMS computes low accurate results if MMS is not able to receive enough signals of Global Navigation Satellite System. When MMS computes bad results, the result is adjusted by Ground Control Point (GCP), which size is not documented in the manual. The purpose of the present research is to investigate GCP size the for a more effective installation method of GCP. As a method, a comparison has been done between the measurement results and calculation results. As a result, the GCP size of minimum error and minimum size of exposure were shown by this receach. The minimum size of GCP is 0.09 meters square in the conditions that the running speed is 40km/h, the GCP is set on the side 10m away from running course, and the laser data are used by one side equipmen.

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 Maintenance management is an essential operation that should be carried out effectively for maintaining, repairing, and rehabilitating highways and roads. In road maintenance site, the administrators and engineers want to refer and utilize the road ledger and its drawings. It is difficult to carry and use the ledgers and documents, because they are paper based documents.
 The primary objective of this study is to solve above problems on road maintenance and maintain the road efficiency. This paper proposed a road inspection support system using AR marker and QR code. The system consists of two functions: the function that AR marker indicates an important inspection point on site and the reference function of inspection and rehabilitation data using QR code. AR marker was used for indicating important inspection points of main girder, crossbeam, and drainage on bridge. QR codes were attached on kilo post at one hundred meter intervals. The inspectors can refer the inspection data of pavement, slope, directional arrow, and sign. And, the product data models were developed, which systematic information is defined for accumulating, exchanging, and sharing in civil infrastructure. The proposed system was evaluated the usability and capability in Shiraito Highland Way in Nagano Prefecture, Japan. The evaluation results indicated usability and capability on site usage. In the future work, the system will use and manage the daily inspection and rehabilitation data.

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 Three-dimensional landform data are generated by laser profiler (LP), mobile mapping system (MMS), laser scanner (LS), and camera on UAV (Unmanned Aerial Vehicle). There are no standards for representing and drawing three-dimensional landform data. In this paper, the first version of three-dimensional landform modeling guideline was proposed. It targets the landform and standardizes a common specification of landform in civil infrastructure domain. It standardizes the notation of view, and proposes to define the contents of conformance class, level of detail, management information, annotation, used point, line, surface and solid, and features. The three-dimensional data measured by LP, MMS, LS and camera on UAV were displayed on Cloud Compare for discussing the view of landform. The results were classified by density of point cloud. The guideline is proposed the menu of view by density of point cloud.

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 The use of 3D modeling at construction sites has expanded rapidly as a result of Construction Information Modeling, which is promoted by the Japanese Ministry of Land, Infrastructure, Transport and Tourism. However, 3D modeling is still in limited use because many cases require special software or high-performance workstations. WebGL is a technology for representing 3D graphics in standard web browsers. It allows 3D models to be shared by users at different locations, which may resolve these kinds of issues. This study considers the effectiveness of applying WebGL to the maintenance and management of civil engineering structures in general and inspection tasks in particular.

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 For better supporting concrete surface crack inspection, this paper presents a real-time visibility evaluation system (VIS system) with video camera for supporting fine crack detection of concrete surface and its practicality. In this system, the power spectra for the fluctuation of digital number values (i.e., spatial frequency components) in each pixel of the animation-like Feature Composite moving image (FC image) inducing visual illusion can be delineated on "Visibility Evaluation image (VE image)." Through the site inspection for various kinds of concrete surfaces of tunnel lining, box culvert and concrete slab bridge, the results can be summarized as follows: i) The simultaneousdisplayingof FC and VE image corresponding to negative and positive moving image is effective in detecting the crack of "0.1-0.2mm" in width, even from the place 10m away from the concrete surface, and ii) Real-time processing of magnification and reduction for FC and VE image contribute to prevent the inspectors overlooking those fine cracks from workbench of vehicle forhigh lift work.

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 In recent years, there is an active movement to introduce costruction information modeling/management(CIM) which has a mechanism similar to BIM in civil engineering, . In order to exploit CIM as needed, understanding information and communications technology (ICT) is important. Thus, we surveyed the current status of ICT for use in mountain tunnel excavation. Subsequently, the items needed for mountain tunnel planning, design, construction, and maintenance were extracted. The CIM of mountain tunnels, needs to be properly integrated with ICT. Therefore, we developed a draft system based on a platform comprising Navisworks, AutoCAD, and Excel. In addition, we are developing the predictive CIM by adding a tunnel face forward geological information such as mechanical and geometric condition on draft system.

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 In view of the progression of the Japanese super-aging society, ensuring the smooth movement of senior persons along pedestrian spaces presents an urgent challenge for all. Technological studies, such as those examining mobile information terminals for walking support, are underway to resolve this issue. Compilation of a 3D database of pedestrian spaces is indispensable for implementation of these technologies. For this study, we collected a 3D database of pedestrian spaces using a hand-cart-type Mobile Mapping System (MMS) while walking along pedestrian spaces. Although this database might include fewer fine data than those compiled by on-car type MMS, it provides a simple system for various purposes. Because a few earlier studies examined the fundamental performance of hand-cart-type MMSs, we instead examined the precision of measurements produced by the system and detected locations of blocks to guide visually impaired people. Those data might be used in a database supporting smooth movement by pedestrians. Furthermore, we assess future methods of compiling databases.

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