Public works have contributed to the construction of high-quality living space and of the country safe and secure against natural disasters. In recent years, however, negative image for public works is spreading in an atmosphere of criticism for public works. The budget is cut and some projects are delayed or stopped due to its difficulty of obtaining public support. We must promote these works with the agreement of the people. Therefore, it is important to understand the people's impression. We carried out the questionnaire about people's image towards some words, regarding to “public works”, twice. As a result, it was suggested that people's negative image toward “public works” could be improved by their recognition of the significance or emergency.

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 In Japan, the government reinforces the environmental regulations and people concern about the environmental stability of waste landfill, so the site of landfill is diversified from inland to coast near urban areas. However, as the standards on their environmental stability and the monitoring methods are not established, the coastal landfills have been built and used without a long-term evaluation on their performance. Therefore this paper shows the methods of evaluations for the impervious walls which prevent leakage of the waste leachate. This paper uses two methods, statistical and physical chemical method. Furthermore, this paper assumes that the environmental damages occur by the leakage through the containment facilities. This paper defines expectation life cycle cost (LCC) is the sum of the repairing cost and environmental damage cost and calculate with the probability by the Weibull distribution. Furthermore, from the viewpoint of asset management, this paper examines the maintenance strategy of landfills.

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 Fault of lamps in tunnel partially reduces road illuminance. Therefore, it becomes difficult to drive comfortably and safely. Thus, it is important for road administrators to quantitatively estimate fault probability of lamps and its effect. In this paper, the final target is to evaluate the risk of the reduction of road illuminance, caused by fault of lamps. For that reason, the statistical methodology is constructed to analyze the influence and range of road illuminance the lamps have. Concretely, the relation between lamps and road illuminance is formulized as a spatial distribution of illuminance model, which considers spatial interaction, and Bayesian estimation is proposed to estimate the unknown parameter and autocorrelation parameter of a spatial distribution of illuminance model. The paper is concluded by illustrating the application examples of the methodology presented in this paper to the data set in the real field.

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 In this study, the authors develop a model of the generating process about peeling/falling of protective covering concrete as a counting process. A model is proposed, considered a time-dependent/independent factor of peeling/falling process. In detail, a time-independent peeling/falling process is presented by the homogeneous Poisson process, a time-dependent process is presented by the non-homogeneous Poisson process where the arrival rates are changed with time. Then, a mixed Poisson deterioration model is formulated by both of Poisson process. Lastly, the appropriateness of the proposed model is discussed empirically, by applying it to actual expressway.

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 Falling objects on highways is one of the direct or indirect factors which induce a major accident. Therefore, in management of highways, the improvement in visibility to falling objects has been an important issue. And, the reflectance distribution of falling objects and the tunnel lighting system greatly influence improvement in the visibility of falling objects. In this study, it is set the eventual goal that the establishment of the decision making of the tunnel lighting system, and as its basic study, it is precisely estimated the reflectance distribution. Specifically, it is represented the reflectance distribution by beta mixture model that can be considered the multimodal and estimated mixing coefficient and unknown parameters of beta mixture model with the aid of the EM algorithm. Finally it is indicated the application example which used the survey data, and verified of the validity of the model in this study.

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 The Great East-Japan Earthquake hit Tohoku area in Japan on March 11, 2011. A large number of water storage facilities were damaged due to the 9.0 magnitude earthquake of the Richter-scale. Prior to reconstruction and retrofit of these structures, damage evaluation of in-situ structures is now in urgent demand. In this concern, damaged dams were investigated (n=143) and qualitative evaluation of damage was conducted by 3D-resistivity survey and microtremor measurement in deteriorated dam bodies (n=2). Thus, the deteriorated of dam body could be evaluated by specific resistance with H/V spectral ratio by microtremor monitoring. A relation between structural damage and monitoring parameters was correlated in deteriorated dam bodies.

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 In recent year, many disasters, for example earthquakes, typhoons, heavy rains and so on, happen in Japan. Especially, in 2011 Tohoku earth quake caused serious damages by tremor and tunami in very large areas. Some people predict that in days to come, some enormous earthquakes happen and cause terrible damages in Tokyo, Japanese capital, and other cities which very many people live. For decreasing damages by such disasters, we have to disperse living and business place from mega cities like Tokyo to other rural areas. It is said that people tend to live in areas that infrastructures constructed. So in this research I predicted the effect of constructing infrastructure like highway and Shinkansen train. And this research suggests that constructing and using infrastructure cause various effects like increasing GDP, tax income tourist.

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 In early stages of a disaster, the contribution of local building constructors of a stricken area is important, and a number of construction heavy equipment is needed for elimination of road obstacles. However, the number of construction heavy equipment which local constructors hold is decreasing under the influence of long-term depression and decrease of expenditure for public works. Minagawa et.al. examined the effect of cooperation between local-governments for elimination of road obstacles in early stages of the disaster for expected Tokai earthquake by using a multi-agent simulator. In this study, first, the influence of transportation route destruction in elimination of road obstacles was considered using the Minagawa's model. Second, the influence of the difference of the attribute of roads and corresponding change of the rubble processing efficiency in elimination of road obstacles was investigated. This research confirmed that the difference of rubble accumulation situation and rubble processing efficiency depending on each road width have significant impact on efficiency in elimination of road obstacles.

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 In creation of a tender estimate and preparation of a working budget, a tendering contractor's standard prices are important. Thus, it is an important issue for each tendering contractor to collect accurate standard prices. Since the method of collecting step charges as a method of collecting standard prices requires much effort and time to collect a large amount of detailed data, the method of collecting order unit prices was employed in this research. However, since no concrete collection method or analysis validation methodology had been developed yet, we decided to build an original standard price feedback system which can collect order unit prices.
 The method of collecting order unit prices involves generation of working budgets and administrative budgets, procurement, and collection of standard unit prices, in order and collected data is filtered by a statistical method. The standard unit price feedback system can display the above collected and filtered data including fiscal years, names of unit price tables, standards, number of track records, actual average unit prices, standard deviations, minimum unit prices, and histograms.
 In this system, itemized working budgets and administrative budgets for elements can interact mutually and itemized unit prices of working budgets are collected ad standard prices. Thus, the system can collect reliable data since all compositions of costs of labor, material, and machine are the same.

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 Inexperienced workers have little knowledge and techniques for work and safety in construction sites, so they need safety education to help them understand the dangers and compensate for their lack of experience. This study examines the potential use of a tablet-PC-based safety-training tool created for introductory education of experienced and inexperienced housing construction workers. The tool displays four work situations on a tablet PC. From these, participants choose one dangerous situation and learn dangerous situations by repeating this. Twenty-eight construction workers, 37 carpenter trainees, and 30 inexperienced workers (college students) participated in the safety training, and the tool's effectiveness was compared for the different experience levels. The tool was also evaluated subjectively by carpenter trainees. Carpenter trainees and inexperienced workers learned to recognize dangers in construction sites quickly and correctly, suggesting that the tool effectively facilitated comprehension of curriculum contents. In particular, the percentage of correct answers of inexperienced workers was initially low but finally increased to the same level as that of construction workers. The interface of the tablet-PC-based safety-training tool needed to be improved, but the subjective evaluation (interest in the safety-training tool and subjective learning effects) of the safety-training tool by carpenter trainees was high. These results suggest the potential use of a tablet-PC-based safety-training tool for introductory education.

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 In this paper, we develop a method called the resource-dependent critical path method (RDCPM) to identify resource dependencies that exist between activities in order to determine the critical paths and real floats in resource-constrained scheduling (RCS) techniques. The popular critical path method (CPM) and program evaluation and review technique (PERT) network techniques are based on the assumption of unlimited resources. This assumption is not valid in most practical applications, wherein exist definite limits on the amount of available resources. Although RCS techniques can consider resource limitations, they do not provide the correct floats and critical path, as do the CPM and PERT techniques. This is because in addition to technological relationships, a resource constraint schedule contains resource dependencies between activities that are neglected in RCS techniques.
 RDCPM provides reasonable resource links between activities so that both total floats and free floats can be computed accurately, and critical activities and critical sequences can be correctly identified. Moreover, to minimize the number of resource links and reduce the complexity of the network, RDCPM establishes resource links between activities while considering their optimization and removes redundant relations. This approach makes a schedule more realistic and provides a stable schedule with progress updates. Therefore, it should be considerably more beneficial and useful for the construction industry.

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 When conducting land readjustment projects, cooperative associasionas occasionally face financial risks caused by anemic sales of reserve lands. In these cases, finding effective countermeasures for these risks and then reconstructing project financial plans using these countermeasures is very important to achieve the projects.
 In this paper, the effectiveness and feasibility of the alternative countermeasures to various risks in the projects are first evaluated in nine Likert scales using questionnaire surveys given to land readjustment project experts. Secondly, based on these results, a flowchart is proposed that the cooperative associations can use to specify the countermeasures and reconstruct project financial plan.

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 “Cooperative infrastructure management” where road facilities are maintained by various stakeholders such as local municipalities, private companies, road users and residents through taking part in the maintenance works are necessary because of lack of the budget and human resource constraints. The keywords are cooperation and residents participation. This paper defines areas where resident participate their infrastructures as regional infrastructures and discuss the essential points of regional infrastructures for cooperation. This paper especially focuses on the provision of materials in Nakatsugawa City, Gifu. The scheme and role of stakeholders are summarized. As a result, it is clarified that the areas of regional infrastructures are related into residents' life. Also the areas are related into the relation between various stakeholders. In order to maintain the regional infrastructure, this paper points out of some essential points. From the perspective of residents, residents' life is necessary. On the other hand, from the perspective of private sectors, to keep their foundation in the region is necessary. Moreover, from the perspective of public sectors, it is important that to participate the residents activities and to facilitate the cooperation between residents and experts.

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 A large number of irrigation infrastructures are dameaged by environmental effects. Prior to reconstruction and retrofit of these structures, renewal method of in-situ structure is now in urgent demand. In this concern, in-situ conservation of corroded steel sheet pile canal is going to be performed, applying steel sheet pile-concrete composite. In the experiments, the mechanical properties of composites were evaluated based on characteristics of displacement due to fracturing under bending test. It was demonstrated that the retrofit in mechanical properties could be evaluated by comparing a moment with a maximum displacement. A relation between mechanical properties and composite properties were correlated. Thus, the corroded steel sheet pile canal is preserved effectively using steel sheet pile-concrete composite.

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 Japan has a wide distribution of soil and rocks containing naturally-occurring heavy metals like arsenic. In recent years, cases of construction workers encountering geological features with heavy metals are on the rise. In particular, construction of tunnels involves the excavation of soil and rocks containing heavy metals, and there is a rising demand for environmental solutions to reduce the impact on surrounding sites. Implementing solutions for excavation of heavy metals requires a quantitative analysis of those excavation procedures; such analysis requires a period of several days, over which time considerations could include storage of excavated contents while in transit and prevention of dispersion or outflow of harmful substances when removed. This research demonstrates how the rapid analysis of excavated content onsite and creation of a practical management system based on communications technology could point a way towards improved disposal and care of heavy metal substances.

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 The Ministry of Land, Infrastructure, Transport and Tourism (MLIT) has extensively adopted Comprehensive Bidding Evaluation Method with Technical Proposal (CBEMTP). Recently, CBEMTP has been adopted by local governments and the expressway companies. Some of local governments and the expressway companies have adopted so-called “summation method”. And there are several methods of evaluation of the price and technical proposal. In this paper, the bidding behaviors are analyzed from the viewpoints of evaluation methods in order to propose improvements of CBEMTP. By comparing the bidding results, the effects on the bidding behaviors are clarified.

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 The quality-and cost-based selection (QCBS) method used by local government has been implemented in all prefecture and designated cities since its introduction by Tokyo Metropolitan Government in 2001, but its actual implementation has not been clarified. This study compares and analyzes the details of QCBS method of 7 prefectures and 4 designated cities in the Kinki Area, and extracted issues such as sluggish growth of implementation rate, the limited implementation of the application area of QCBS method, and the insufficient of the system design for effective competition. In addition to this, we have proposed application of QCBS method to general competition bidding method as a rule, changing the main technical evaluation method to special simplified method, and improvements to the system design to increase the effectiveness of technical competition according to these analysis results.

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 This study examines tendering data on bid and win prices for general civil engineering work by Tokyu A and B in 2002-2010. Regression analysis is conducted on the data, which are based on information from Shikoku Regional Development Bureau, Ministry of Land Infrastructure, Transport and Tourism, by using factors such as the predetermined price and number of participants to capture the actual situation regarding examination trigger price changes. According to analysis results, the price change in 2008 did not affect bid and win prices and those in 2009 and 2011 had a positive but not statistically significant effect. However, there was a mechanism that if the hiking examination caused avoidance of a firm's contract or invalidation of the bid, the price would be increased by the firm's appropriate trial and error. On testing this mechanism, when the probability of avoidance and invalidation of bids is analyzed, the changes in 2009 and 2011 have positive coefficients and are statistically significant, thus validating the mechanism.

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 Design-build is a method of project delivery through a single contract to provide design and construction services. The use of this method is expected to bring about a number of positive effects including utilization of exquisite techniques of private sectors, ensured quality of design and construction services, streamlined construction design commensurate with construction capability, and improved effectiveness by consistent flow of both services.
 In this study, actual contract documents of design-build projects, which are used to form an agreement between the project owner and the contractor in the procurement process of the projects under ministerial jurisdiction, have been examined to clarify points differed from contract documents applied to projects delivered with design-bid-build method. Using these results, it further proposes structures and provisions of a standard form of design-build contract between the project owner and the contractor, for use in design-build projects under ministerial jurisdiction.

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 The aim of this paper is to propose a support system for overall evaluation bidding method to small and medium-sized regional local governments. The act on progress to ensure quality of public works in 2004 requests to introduce smoothly the bidding system with transparency and fairness for public procurement.
 However, approximate 70% of the local government introduced the bidding method in 2012. Especially, many small and medium-sized governments are in a trial level of the system. The reason is why the system has unavoidably long-term procedure and heavily administrative load rather than other bidding methods. In a few results of the bidding in local government, we conducted a questionnaire survey to local governments. In according to the result of analysis, we would like to propose the following things.
 1. The Japanese government should show applicable criteria for overall evaluation bidding method and
 2. Pool people of experience or academic standing for third party committee of the bidding system,
 3. Apply a "regional cooperation system" in public procurement.

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 The companies of construction engineering service such as designs, investigation, research, etc, are divided generally into three categories of major, local and semi-major companies. The local consultant companies are essential in emergency including disaster since they could immediately implement the survey and inquiry of the damaged sites and emergency recovery just after disasters have happened. It becomes more necessary that the local consultant companies would be promoted and that they would keep and improve the technological skills.
 We put in order the opinions at the hearing from some associations of construction consultant companies, verified the problems on the competiton between major and local companies which the associations pointed out analyzing the procurement data by Ministry of Land, Infrastructure, Transport and Tourism in fiscal year 2011, and studied the improvement of the procurement system.

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 The dumping prevention system have greatly decreased the low price of successful biddings in the Quality and Cost Based Selection System(QCBS). On the other hand, many bidding prices are immediately above the threshold price for low price inquiry. Some possibilities emerged after the interviews with bidders. The reason of such bidder's action seems that many bidders didn't consider about capabilities of their own engneerings, when they decided the bidding price.
 On this study, we review the latest trend of QCBS, and examine the recent problem of QCBS, that is way of evaluation approach about quality and price.

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 In Japan, investment in construction has been decreasing, but the number of companies of construction industry has not been decreasing at the same degree. Therefore, Japanese construction industry is in excessive competition. Generally, there are two types of prospects that industry in excessive competition will have. One is that natural selection of companies will occur. The other is that all companies share a little demand and they gradually lose their capital. In this case, it is likely that construction industry falls into decay.This paper shows which types of prospects Japanese construction industry will have in the future by using the bidding simulation, analyzing the case of civil engineering works in Oita Prefecture. Results show that the differences among the contractors are narrowing both in orders and perceived technical competency.

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 To promote the sustainable efforts of regional resource utilization, it is necessary that each local government has a mechanism and a process to review the policy in conjunction with stakeholders. In that process, regional characteristics and geographical factors in each region should be considered. For supporting the review process of concerning policy, this study investigates a method to evaluate the effects of conditions of the regional distribution centers give, focusing on farmers' direct markets as main regional distribution centers of agricultural resources.
 In order to grasp the influence quantitatively, a simulation is performed by modeling the behavior of farmers and consumers incorporated with the geographic elements within the region. The results of simulation are evaluated not only with the number of users, but also with the utility of farmers and consumers and the performance of the distribution system.

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 The annual amount of precipitation including snowfall tends to greatly fluctuate probably because of global warming. To minimize the risk of an unexpected increase in snow remocal expenditures due to unusual heavy snowfall, barious budgetary measures including national or prefectural supplementary budgets are prepared. In constrast, for a winter with scant snowfall, measures to minimize snow removal contractors' risk that they cannot gain the expected profit from snow removal work have been largely limited. In addition, some snow removal contract systems have been changed, which has made the contractors' finantial risk greater than before the change. As a result, in Fukushima Prfecture in 2009, no bidder appeared for a snow removal contract. If the no. of snow removal contractors decreases due to the extreme fuluctuations of snowfall, snow removal will not be able to be sufficiently realized in the cold, snow regions that account for about 60% of Japan's land area, and this may make winter living in such regions insecure and unstable. The authors developed a snow removal cost estimation model that uses a linear regression line of “unit cost of snow removal” (UCSR). UCSR decreases with increases in culuative snowfall. Through the model, this study evaluates the contractors' risk in a year with unusually little snowfall and seek how to address the risk.

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 Reconstruction from the Great East Japan Earthquake has not progressed noticeably after two years. Unprecedented damage was caused by great earthquake and massive tsunami, and in addition, it can be considered that there is also cause in the reconstruction system by municipality organization and the central government. The previous Earthquake disaster recovery has been mainly the restoration and reconstruction for the inland earthquakes. For this reason, the coastal type earthquake can not take full experience from the past and entire reconstruction has been fallen behind. This is because municipality organization was not ready for pre-disaster action plan for reconstruction for the disaster and the central government has tried to bring the peacetime system and law regulation into large scale disaster. In this paper, the authors found the necessity of disaster management system which covers from recovery to reconstruction by clarifying the problems of organization and law regulation for rapid reconstruction, from the point of view of “Local Public Management” that municipality organization makes effective policy and executes in accordance with actual condition in local area.

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 In Japan, it has been said that productivity in construction industry is lower than other industries. Also, reduction in public investment has led to a cost reduction of excessive and may hinder the improvement of productivity in the construction industry. The purpose of this paper is to summarize how technology in construction industry progress under the social background and clarify the issues of the construction industry in Japan. In empirical study, Total Factor Productivity of construction industry was calculated as an indicator of technological progress in macro and microeconomic levels. In macro study, TFP in construction industry is compared with TFP in other industries. In micro study, TFP of each contractors company was compared by each hierarchical levels. Then, each characteristic is clarified and the issues in Japan was considered. As a result of macro study, TFP of construction industry has declined. Also, in the micro study, TFP in higer level of company has increased but in lower one has declined. These results suggest that construction industry has employment adjustment issues.

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 Rapid emergency response were performed by construction constracots and so on. In this paper, the factors of the rapid emergency response by region were analyzed with the survey result conducted by National Institute for Land and Infrastructure Management, MILIT, Tohoku Regional Bureau, MLIT, and Organization of TOHOKU Construction Contractors Association. As a result, it was found that construction contractors used their own resources; however, they also had to use another company's one in coast region.

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 This paper analyzed the current situation for the system of human resource development and evaluation method for young civil engineers by using two types of questionnaire. As a result, it is clarified that the rate of recognition of evaluation item for the ability as an engineer varies with the industry sector and the job environment by aggregate analyses. In addition, we conducted linear discriminant analyses in order to reveal the influence factor associated with both the satisfaction with their works and the acceptability of their abilities. According to the results, it is shown that the challenging atmosphere relates to their satisfactions, and the job environment of each sector has an influence on the acceptability of them. Furthermore, we focused on the relationship between the administrator as a rater and the engineer evaluated by the rater, and analyzed what the evaluation items are valued more for both parties. The result was that there are the differences between the rater and the young engineer, while the conscious-ness of young engineer is similar to that of student for all industry sectors.

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 In this study, clarifies necessary quantity of construction machinery required for disaster correspondence for every area for improvement in local disaster prevention power. In the Kyushu district, the threat of a natural disaster is large. Moreover, public service density is falling by progress and the municipal merger of aging of a depopulated area. The capability corresponding to a disaster is declining.
 So, in this study, the disaster situation was investigated for grasp of the necessary quantity of the construction machinery for every area in Kyushu. Next, the questionnaire was performed to 149 construction machinery lease-and-rental companies of the Kyushu district. The geographical distribution of construction machinery was able to be clarified by measuring the necessary quantity of construction machinery, and available supplies. Moreover, the issue which future should tackle was described.

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 Towards a low carbon society, Tochigi prefecture tries to promote the introduction of energy saving equipment and the use of renewable energy. This is because the prefecture is facing an tight financial condition, and are forced to work on a financial plan to rebuild its financial base. In such backgrounds, the prefecture devised the dam ESCO system, in order to aim at cutting down on administrative expenses, reduction of an environmental impact, and also effective use of hydraulic power energy which hadn't been used at an old dam. The dam ESCO system can save the energy of equipment at a dam. Moreover a prefecture generates electricity by utilizing funds, executive ability, etc. which civilian enterprise companies have. And also the prefecture can install a hydroelectric power generator in its dam. This report is written on an action about the introduction of the dam ESCO system of Tochigi Prefecture.

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 On 7 of July 2008, the sacred Site of Preah Vihear was inscribed into the list of World Heritage. Preah Vihear province is one of the least inhabited compared to other regions, and is one of the most undeveloped regions in Cambodia. In this paper, the authors discuss the past development trend, present issues to develop, in order for the future sustainable development of the valuable heritage region. Since the area has the potential for agriculture production, the long term vision as well as the development policy should be established for the success of sustainable development for the overcome of the poverty.

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