The behavior of pipeline in liquefied ground is not fully elucidated. Therefore, the seismic design is not established systematically. The thrust force due to the bending angle and internal pressure constantly acts on the bend. The resistance for the thrust force is passive earth pressure behind the bend, but it is not considered that the passive earth pressure decreases when the liquefaction occurs. In this study, lateral loading tests were carried out in order to discuss the mechanical behavior of flexible joints pipeline with a bend in the liquefied ground. As a result, it was revealed that the horizontal resistance force decreases significantly, and the horizontal displacement of pipeline increases during liquefaction. In addition, it was confirmed that the numerical simulation modeled by beam and spring elements agreed well with the lateral loading tests.

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Continuous irrigation with running water (CIRW) experiments were conducted in an experimental paddy field under different amount of irrigation water, water depth, and irrigation timing condition, and the effects of these irrigation conditions on water temperature in paddy field were studied. The effect of cooling by inflow of irrigation water exhibited positive and negative relationships with amount of irrigation water and water depth, respectively. CIRW during nighttime was more effective than that of daytime, under the same conditions of irrigation amount and weir height. On the other hand, changes in water temperature at the area that did not receive cool irrigation water became slower with increase in water depth that increased heat capacity of paddy water. Thus, higher (lower) water depth kept water temperature cooler in daytime (nighttime).

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To clarify the deformation behavior of an irrigation tunnel with a void behind its lining, a model experiment applying vertical load was performed. The test specimens consisted of lining, peripheral ground, and several ranges of voids behind the lining. The lining was made of mortar and peripheral ground around the tunnel lining was made of low-strength mortar. Stress on the lining and the deformation of the inner section were measured, and the movement of peripheral ground was analyzed by the digital image correlation method. When there was no void, or the void was in the range of 45 degrees, the lining was deformed in the vertical direction. Whereas, in a case where the range of the void was 90 degrees, the peripheral ground moved into the tunnel as the deformation progressed, resulting in the inner section being expanded in the vertical direction and reduced in the horizontal direction.

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We investigated some practical application methods of snow-depth measurement technique based on snow temperature profile for the purpose of observing snow depths in high mountainous and forest areas. Small temperature loggers were attached to poles at 20cm intervals from ground surface. Snow depths were estimated by assessing the daily variations in air and snow temperature. The material and color of the poles and the support provided to the poles did not affect the estimation accuracy significantly. If the standard deviation recorded by a temperature logger in a given day was less than 0.3°C, the logger was considered to be covered by snow. The observation error of this method may be approximately 75% of the attached interval; the method is inexpensive and robust, and it can be applied in inaccessible high mountainous and forest areas.

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In order to apply the repair and reinforcement to aged pipes, it is necessary to evaluate the remaining strength of the pipes including their surrounding soil and foundations. In this research, the internal loading method that can be evaluated the strength of buried pipes is proposed. This method aims to evaluate the degree of deterioration (especially cracking and material deterioration) by measuring the relationship between the load and deformation. Experiments with this method were conducted for flexible PVC pipes with and without kerfs. As a result, it was confirmed to be capable of detecting the change in stiffness of a pipe caused by different types of kerfs. And then, it was considered that the influence of the occurrence position in the circumferential direction. Furthermore, even in the same pipe, it was confirmed that the difference of the measurement position influences the deformation in the axial direction.

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Swimming experiments were conducted in the field using weather loach (Misgurnus anguillicaudatus) fry in order to study its swimming ability. The experimental equipment used was a stamina tunnel, which was installed at a local dry riverbed. During one swimming experiment, the relationship between swimming speed and time, and the relationship between velocity and swimming distance were considered. For weather loach with body lengths of between 4 cm and 5 cm, the results show that 1) a swimming-curve-formula defining the relationship between swimming speed and swimming time was obtained, 2) swimming time of the weather loach whose body length is between 4 cm and 5 cm was shorter than those whose body length is more than 5 cm in the same flow velocity conditions, 3) the critical flow velocity in which the weather loach could swim up was 43-55 cm•s^-1, and 4) in the case of a small scale fishway for fishes in paddy field design for weather loach in which the flow velocity in the small scale fishway for fishes in paddy field is made to be 30 cm•s^-1 or about 40 cm•s^-1, many individuals seem to be able to ascend, as the necessary passage distance was respectively made to be 30 cm or less and 10 cm or less.

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The integrated agricultural and rural development is recognized as one of the important program for the poverty alleviation. However, only few such projects are supported by yen loan due to the lack of information on the effective combinations of different project interventions and implementation mechanisms. The Agrarian Reform Infrastructure Support Project has been implemented by yen loan in the Philippines for poverty alleviation. Effective implementation mechanism of integrated agricultural and rural development has been identified from experiences in implementing ARISP over 20 years. To improve poverty conditions in numerous farm villages scattered nationwide, packaging development interventions into a small scale integrated agricultural and rural development project and covering many farm villages is proved to be an effective approach. In addition, factors such as establishment of flexible implementation mechanism, adoption of simple and standard facilities, focusing on O&M stage and promotion of the work/cost implementation sharing between central government and local government/ beneficiaries are key elements that should be fully taken into account. Furthermore, the focus of the project proposal of poverty alleviation programs should be more on poverty reduction interventions rather than development potential.

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