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Concerns regarding the high level of research and development (R&D) expenditure on military technology have prompted many nations to pursue a dual-use regime in military R&D. However, the value of dual-use military technology has not yet been quantitatively investigated. We explore whether military technology with a higher level of duality has been more valuable than that with a lower level of duality. We assume that the patent of valuable military technology was renewed until its termination. We retrieve military patents from the United States Patent and Trademark Office during 1976–2014 based on their International Patent Classification (IPC) as F41 or F42. Then, we propose three indicators to assess the duality level of them. The first indicator is based on the determination of whether the patented technology is utilizable in both the military and the civilian sectors using its IPC. For the second indicator, we estimate the potential of convergence of a patented technology with various technological fields using the degree of centrality of the IPC’s co-occurrence network. The third indicator is based on ratio of forward citation by the civilian sector over the total number of forward citations as a measurement of technology diffusion toward the civilian sector. Using logistic regression, we found that the first two indicators are positively associated with patent renewal decision, while the last indicator is nonsignificant. The effects of the two significant indicators suggests that military technologies are more valuable when the technology itself can be used in various sectors, including the civilian sector, and can be converged with technologies in different fields. However, the nonsignificant influence of the third variable suggests that the relation between patent value and diffusion effects toward following inventions is not confined to the civilian sector. Our findings provide evidence of the impact of dual-use policies in military R&D.  相似文献   
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It is argued that the term with the negative sign in the rate expression for an equilibrium-limited gas–solid reaction can be viewed as representing a lowering of the concentration driving force for the forward reaction due to equilibrium limitation. While the gas composition favors the forward reaction, the negative term may represent the local rate of the reverse reaction. When the gas composition changes significantly to the opposite side of equilibrium, however, this term as written for the forward reaction does not represent the rate of the reverse reaction. Even the reaction order with respect to the same gaseous species may become different for the reverse reaction.  相似文献   
65.
The effects of different types of reducing gas on swelling and iron whisker formation during the reduction of iron oxide compacts were investigated. The compacts sintered in air at 1273 K were reduced at 1173 K in different reducing atmospheres. The results indicated that catastrophic swelling can happen in CO but not when H2 is present in the reducing gas mixture. Scanning electron microscope (SEM) micrographs showed that catastrophic swelling was caused by a large amount of long iron whiskers formed during the reduction. The presence of N2 and CO2 in CO changed the amount of long iron whiskers and its distribution, which determined the extent of swelling.  相似文献   
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An automatic mackerel grader is a machine that automatically sorts mackerel according to size. The chute spreads the mackerel to allow the latter to enter each roller evenly. Sorting is simulated to confirm that the multibody dynamics model of the automatic grader correctly sorts the mackerel. This process is completed according to the shape of the chute to confirm the effect on performance. A new shape of the chute and the application are proposed and evaluated by a comparison with conventional chute shapes. RecurDyn, a multi-body dynamics program, is used for the sorting simulation. The contact parameters are defined by Hertzian contact theory using the material information of mackerel and C/S steel. A rigid-body mackerel model is used to express the behavior of mackerel. Sorting is simulated for each shape. The sorting accuracy and error of the new shape are compared with those of two existing shapes. The new shape shows a 0.29 mm sorting error and better sorting accuracy than the existing shapes.  相似文献   
68.
Wastewater produced during recycling of spent lithium primary battery was biologically treated with Acidithiobacillus ferrooxidans to decrease the pH and metal concentration. Since the wastewater contains high concentrations of Cr, Ni, and Li, the effects of these metals on the bacterial activity in a 9 K medium were also investigated. Samples of the medium with different metal concentrations were treated, and the oxidation ratio of Fe2+ ions was measured to examine the activity of bacteria. In the treatment of simulated wastewater, the presence of Cr and Ni ions with concentrations of 8000 g m?3 and 13,000 g m?3, respectively, did not inhibit the bacterial activity, whereas the oxidation ratio of Fe2+ ions was observed to be low in the medium when Li ion was present with a concentration at 5000 g m?3. This observation suggested that at this concentration, Li ion suppressed the bacterial activity. In the case of treatment of real wastewater containing Cr, Ni, and Li, the oxidation ratio of Fe2+ to Fe3+ was observed to be low while the Fe concentration and pH decreased to 21,633 g m?3 and 1.8, respectively. Thus, the wastewater produced during the recycling of spent lithium primary batteries can be effectively treated biologically for re-circulating in the recycling process.  相似文献   
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Journal of Mechanical Science and Technology - Recently, domestic gas turbines are primarily operated under partial loads. Hence, thermal expansion of components decreases, leading to a...  相似文献   
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Journal of Mechanical Science and Technology - In this paper, to help reduce the squeal noise produced during the braking of urban railway vehicles, the shape of the disc brake pad was investigated...  相似文献   
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