Rainfall erosivity and impact forces are key meteorological parameters for predicting rainfall-induced hazards and disasters. Erosivity of rainfall is widely indicated by its kinetic energy or momentum that is widely derived from drop diameters or drop size distribution and velocity of raindrops. Raindrop velocity and impact forces describe the rainfall erosivity dissipated to impacting surface. These parameters are not commonly evaluated and available in practice due to cost and capability of measuring instruments. A strain gauge-based device was developed for automatic and continuous measurement of the parameters in laboratory. The strain sensor, with the aid of a portable, dynamic, and high frequency data acquisition, was calibrated to capture the falling velocity of a 4.00 mm diameter waterdrop with varying heights. Results of the falling velocities of a waterdrop against heights in this study showed a close agreement with results from literature data and equations for the falling velocity and its impact force of a waterdrop were derived. In addition, results of using the equations to derive terminal velocities and impact forces as a function of drop diameters were presented.

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This paper presents the result of cyclic loading tests followed by water infiltration on unsaturated sandy samples to study possible slope failures in earthquake areas. The cyclic tri-axial tests and dynamic measurements were carried out on Edosaki sand, silica sand taken from a natural slope in Chiba prefecture in Japan. The specimens were first consolidated in anisotropic condition with a principal stress ratio (K = 2), and then cyclically loaded under un-drained conditions. After cyclic loading, water infiltration was applied to the specimens until failure after different periods of waiting time. During the tests, the elastic wave velocities were continuously measured. Test results clearly show the variation of stiffness during cyclic loading and infiltration attributed to changes in relative density. Test results also confirm that there is a possible threshold value for the cyclic amplitude that causes a rearrangement of the soil skeleton and gives rise to higher failure resistance during water infiltration after reconsolidation. In short, it is very useful to monitor the stiffness and pore water pressure in a slope after an earthquake in areas with high and frequent rainfall.

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There is growing social concern about water environment issue including eutrophication, water pollution in the water bodies, and hazardous contaminants in lowland groundwater. Following extensive research into wastewater characteristics, the understanding of the potential effects of wastewater on health and the environment has become more comprehensive. Soil and water in lowland areas are especially easily contaminated by heavy metals, toxicant chemicals from waste disposal landfill sites and factories, and natural disasters. These events have prompted the search for suitable solutions. Several treatment methods have been developed to deal with health and environmental concerns associated with the findings of recent research. In this paper, a new adsorbent is characterized and the adsorption of harmful substances dissolved in leachate has been studied. Nano size Layered Double Hydrotalcite (NLDH) and Zeolite (Ze) have been combined to synthesize a more powerful adsorbent, which successfully adsorb both anion and cation at the same time; cations and anions were simultaneously recovered at the same time over 3 hours, under an initial pH of 6 at 20°C using 0.5 gram and 1 gram per liter of the hybrid adsorbent (HB). Other adsorbents were used to validate the efficiency of a new hybrid adsorbent (HB).

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The issue that many Chinese cities follow similar international styles degrades local cultural customs and regional ethnic features, and it is drawing much attention of citizens, governors and designers. Some research has corroborated the effectiveness of correlation and integrity of native urban sceneries, to deal with the above issue. Urban landscape can be regarded as a dynamic network system, comprising some interlinked spots and regions. Based on the current situation and academic proceedings, this research introduced the concept of urban landscape network. By a case study of Hangzhou City construction, this paper conducted a grid analysis of the landscape grid network, and built four sub-networks: natural scenery, historical development, road transportation, and land use. Using variance analysis, correlation analysis, multiple regression analysis, this paper examines the relationship between the four sub-networks, and finally achieved an appropriate regression equation of the landscape network in accordance with the subjective satisfaction evaluation concerning the landscape quality.

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Now-a-days the industrial revolution is taking place in Bangladesh like the other developing countries. The number of industries is increasing resulting the increased number of migrant people as workers. This large amount of people demands housing. To meet this demand, the land owners are constructing houses without considering the quality. This study tends to explore the existing housing condition of garment workers in a sub-city Savar, near Dhaka. All the information about the garments workers were collected by observation, questionnaire survey and personal interview method. The aspects that mainly considered in this study were type and material of house, size of room and occupancy, related facilities and services such as water supply, electricity, drainage, solid waste management and so on. It was found that the garment workers usually rent a single room in a group housing whatever the family size is. In a group housing a minimum of 5 and maximum 35 family lived. They shared the kitchen, toilet and bathroom. A considerable number of workers (about 40%) were still use wood in the kitchen. Corrugated Iron sheet was the main housing material as well as brick, concrete, bamboo and mud were used. The workers living in the study area faced the problems of frequent load shedding, lack of proper drainage system and absence of solid waste management system. In fact, the garment workers are rural migrants and inexperienced in urban life. They are not concerned about the facilities they should get with housing.

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Under the tide of green building, many countries introduce actively evaluation standards of green campus and develop the construction of green campus. China introduced the Green Campus Evaluation Standards (CSUS / GBC04-2013) (short for Standard in the following) subsequently. While compared with green campus evaluation standards of other countries, it is still in the start stage and has many shortcomings, for this reason, in order to optimize Standard by studying United States green campus evaluation standard STARS. Comparing China's standard with the US STARS2.0 to analyze the differences and the cause of differences from the three aspects including the organization model, methods and contents of evaluation. Then combined with China's actual situation to analyze the suitability of application of STARS in our country. Finally, study the reasonable place of the STARS, from three aspects to provide Standard with concrete improvement suggestions and give China's green campus construction a better guidance.

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