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[en] We developed an optimization model for determining thinning schedules in planted teak (Tectona grandis L.f.) stands that maximize the financial output in terms of soil expectation value (SEV) and net present value (NPV) considering a) the simultaneous optimization of timber production and carbon (C) sequestration and b) only for C sequestration. Planted teak forests in the western alluvial plains of Venezuela. We integrated a stand growth and yield model with a constrained optimization model based on genetic algorithms (GA) for determining optimal thinning schedules (number, age, and removal intensity) that maximize SEV when simultaneously managing for timber production and C sequestration. The data came from permanent plots established in planted teak stands with remeasurements from 2 to 32 yr.-old. Plots differ in site quality, initial spacing, and thinning schedules. We obtained optimal thinning schedules for several scenarios combining site quality, initial spacing, interest rates, harvest and transport costs, as well as timber and C prices. The stand growth and yield model estimates timber products and C flows (storage and emissions) until most stored C is reemitted to the atmosphere. When considering simultaneously both, timber production and C sequestration, the scenario with the maximum SEV consisted of initial stand densities = 1,111 trees ha-1, site quality (SQ) I, harvest age 20 years, and four thinnings (ages 6, 10, 14, 17 with removal intensities 26 %, 28 %, 39 %, and 25 % of stand basal area respectively). For maximizing C sequestration only, the best schedule consisted of 1,600 trees ha-1, SQ I, harvest age 25 years, with no-thinning. A sensitivity analysis showed that optimal schedules and SEV were highly sensitive to changes in interest rates, growth rates, and timber prices.
[en] Ion sources are devices which generate ions of atoms of interest which can be extracted as an ion beam by applying suitable extraction method. An ideal ion source shall produce high intensity ions with a minimum emittance for the experimental interest. The development of such low emittance ion sources have a great contemporary significance. They are used for various purposes such as radioactive ion beam production and sophisticated nuclear astrophysics experiments. Keeping the above facts in view, to produce a low emittance, high intensity ion beam, a low temperature plasma has been generated. Further the ion transport has been verified through simulation studies for understanding the extracted beam properties
[en] The purpose of this research was carried out with developing biomaterials by increase of extracting yield and functionality of natural ingredient and contributing high value technology in field of beauty industry. - In this project, We optimized effective extraction method for active components in natural ingredient using irradiation technology and developed radiation fusion technology-applied biomaterial ingredient. On the basis of these results, we developed two healthcare material and one prototype, and our result can suggest a new paradigm for development of functional cosmetics and cosmeceuticals in beauty and health industries. Furthermore, our findings contribute to minimize side effects of synthetic materials and act as supplemental cosmetics for skin diseases. - Consequently, our outcomes indicate that application of radiation fusion technology will be valuably applicated in various industrial field
[en] Nuclear emulsion detector played important role in the studies of high energy interactions during the twentieth century. In this report, the focus is on the characteristics of the shower particles produced in the interaction of 84Kr with nuclear emulsion detector at relativistic energy
[en] To commemorate the 500th anniversary of the city of Havana, the Isotope Center reviews its activity since its creation. The production of radionuclidemarked compounds and other radiochemical work at the Institute of Nuclear Physics, inaugurated in 1969, stimulated the applications of open radioactive sources, which can be considered as the most tangible organized antecedent of the center. Later in the 1980s, the Executive Secretary for Nuclear Affairs accelerated, diversified and expanded nuclear applications, developed the training of highly qualified staff and experts as well as international cooperation. The creation of the Center for Applied Nuclear Development Studies coincided with the consolidation of a group of biotechnological research and production institutions and with these applications gaining importance in Nuclear Medicine. It was soon recognized that it was not possible to continue managing a growing inventory of radionuclides. As a result, CENTIS, a specialized center with a complete cycle, was designed and built, which comprised not only research and development, but also production and marketing. When in 1994 CENTIS became part of the Nuclear Energy Agency, investment was concluded and the production methodologies of the most important radiopharmaceuticals were established. In more than 20 years of work CENTIS has become the main support of Nuclear Medicine in the country. With its metrological capabilities in the magnitude of radioactivity and its non-clinical and clinical research, it is increasingly part of the socio-economic life of the country and its capital. In this paper the main results of each stage are detailed in relation to the mission of the center and a technical assessment is made regarding the actions taken to favor their target sectors: health and biomedical research. Periods of five years in favor of centuries.
[en] The source terms of fission products in the airborne effluents of the CPR1000 and HPR1000 (Hualong One) nuclear power plants (NPPs) in China were estimated for cycles without fuel failure. We used both the operational data for the primary coolants of domestic and foreign NPPs as well as the latest research on reactor source terms for this purpose. The results indicated that the activity concentrations of fission product nuclides in the gaseous effluents were two orders of magnitude lower than the detection limit of laboratory instruments. After comparing the domestic and foreign regulations on gaseous effluent monitoring of NPPs and reviewing the domestic gaseous effluent monitoring practices, recommendations on gaseous effluent monitoring were offered in this paper. This study could provide a technical basis for gaseous effluent management for NPPs and help revise the relevant Chinese regulations and standards in the future. (author)
[en] Every production facility is made of several essential functions such as raw material management, material processing function, branding and distribution function. Apart from these vital functions, there are supporting functions such as quality control and equipment-maintenance (hereafter called as 'maintenance' in short). The subject matter of maintenance had grown in a formal manner had branched into concepts such as breakdown maintenance, preventive maintenance, predictive maintenance, Total Quality Maintenance, and so on. The maintenance workforce, though had not implemented these concepts in a formal manner, had silently assimilated these concepts and implemented an amalgamated work style to meet the requirements of the production plant. Their experience had revealed that, while creativity is an essential requirement of research work, even maintenance work gets enriched by allowing ourselves to creativity. This paper is a brief description of application of creativity in maintenance activities in order to make success in minimum time and cost, to ultimately support production
[en] Raising the operating effectiveness of wells at different stages of their development is one of the most promising trends in oil-gas extraction branch. In connection with the increase of technogenic pollution of the environment, there is a need for control and environmental assessment of the quality of oil and gas production.
[en] Canada remains a Tier 1 Nuclear Nation for Radioisotope production, Radiotracer design, Radiotracer utilization, Radiopharmaceutical research and development. The field of radioisotopes is much more than any one activity. Collaboration is key to enabling innovation and building knowledge infrastructure. Maintaining physical and knowledge infrastructure is key to advancing science and technology in Canada and ensuring access to new medical technologies
[en] This observatory takes stock of the production, commercialization and consumption of fire log, wood chips and pellets for wood burning appliances and collective installations in Auvergne-Rhone-Alpes: typology of suppliers, wood fuel supplies, transformation and artificial drying, regional air quality evolution, wood fuel industry challenges, regional companies directory, quality assurance labels and their progress, wood fuel consumption and commercialization, focus on wood pellets and wood chips