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81.
Most provinces in Indonesia will be facing water scarcity problems in the next decades due to increasing water demands resulting from population growth, urbanization and economic and industrial developments. As a consequence, they will also be facing a number of problems with regards water resource management, such as a lack of data and information needed to evaluate the real status of water resources, the unsystematic development of relevant infrastructure and economic instruments, inadequate human resources for the operation and maintenance of water resources, and a lack of interest in improving research and development activities. This paper examines the application of data and information management for improved water resources management in Indonesia through “one door data service system” linked among the related institutions from different sectors and levels both at the central and regional government agencies. One of the key solutions to help solve water resource problems would therefore be to obtain supporting data and information by developing an information system and water resources data centre (WRDC). Rapid developments in information and communication technology (ICT) could be used to support data communication and management requests in order to build capacity of the water resources sector, and as a prerequisite for an integrated water resources management program. Improved efficiency and effectiveness could be achieved by making relevant data and information available, as well by establishing a communication system among related institutions. Further, provinces should also prioritize developing human and social capital through education, service delivery and career development, as well as training for water resources development and management. Data and information such as the hydrological and water quality data, information of water resources potential, irrigation areas, population and economic growth as well as the others related data need to store in both the tabular and spatial formats. The water resources data management and warehouse system is a web-enabled application that permits spatial data to be stored with tabular data in a standard database management system. This system permits a dynamic generation of output from the tabular and spatial data and enables users to generate answers to their queries online, rather than simply presenting static maps and tables from the database. The WRDC applications were developed and chosen by gathering the ideas suggested by users at the ministerial, provincial and river basin levels. Within the resulting inventory system, information was grouped into irrigation scheme system; water resources potential; natural disaster; hydrological data and station networks; and other information. For the users at the ministerial level access the system by using local area network (LAN) connections and other users at the provincial and river basin levels or elsewhere in the world can use the internet for connections and regular browser software for system operation.  相似文献   
82.
Recent technological advances demanded polyimides of improved versatility in terms of electronic, optical and thermal properties. In this work, a series of poly(siloxane–imide) block copolymers were synthesized in order to investigate the effect on their optical and electronic properties. The polyimide unit was derived from 3,3′,4,4′-Biphenyltetracarboxylic dianhydride (BPDA) and 4-(4-{1-[4-(4-aminophenoxy) phenyl]-1-methylethyl} phenoxy) aniline (BAPP) while the siloxane unit was derived from 3-[3-(3-aminopropyl)-1,1,3,3-tetramethyldisiloxanyl] propylamine (DMS) and Poly(dimethylsiloxane), bis(3-aminopropyl)terminated (PDMS). The structure of the polyimide was characterized by fourier transformer infra red (FT-IR), nuclear magnetic resonance (NMR) spectroscopy, elemental analysis, solution viscosity and gas permeation chromatography (GPC). Scanning electron microscope (SEM) analysis suggested a microphase separation between the two components. The refractive index and dielectric properties showed a decreasing trend with increased silicone unit in the polyimide backbone. However ultra violet visible (UV–Vis) and optical transparency was not significantly affected. Electronic and optical properties of this copolymer were discussed in relation to the polysiloxane content.  相似文献   
83.
The threshold of the absorption spectra of colloidal cadmium sulfide (CdS) quantum dots in electrolytic solutions is shown to shift as the concentration of the electrolyte is varied. The shift in the absorption threshold as a function of the electrolytic concentration is given by electrolytic screening of the field caused by the intrinsic spontaneous polarization of these würtzite quantum dots. These electrolyte-dependent absorption properties are compared with Fermi-level tuning in carbon nanotubes in electrolytic environments.Moreover, concepts for integrating such colloidal quantum dots in high density networks with biomolecular links are discussed. Such biomolecular links are used to facilitate the chemically-directed assembly of quantum dots networks with densities approximating 1017 cm−3.  相似文献   
84.
Blends of polypropylene (PP)/ethylene-propylene diene terpolymer (EPDM)/natural rubber (NR) with different ratio were investigated using a Haake torque rheometer. The effect of N,N-m-phenylene bismaleimide (HVA-2) addition on the flow behavior of PP/EPDM/NR blends also was studied. The torque data was collected at different rotor speeds in the range of 30–60 rpm and different processing temperatures in the range of 170–190°C. The recorded data were interpreted in terms of apparent shear rate, apparent shear stress, and apparent viscosity. The shear stress–shear strain curve shows that all blends follow the power law where the pseudoplasticity behavior of melt viscosity increases with increasing NR content as well as addition of HVA-2. The apparent viscosity of the blends was found to increase with increasing NR content in the blend. The addition of HVA-2 increases the apparent viscosity due to the formation of cross-linking in rubber phase. However, blends with HVA-2 show lower flow activation energies than do similar blends without HVA-2. Scanning electron microscopy (SEM) shows good correlation with the flow properties of the blends.  相似文献   
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