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11.
This paper presents an integrated framework for risk evaluation and risk allocation with bounded data in a critical risk management. A risk evaluation framework using the Imprecise Data Envelopment Analysis (IDEA) method is proposed to be applied to operations of Korean Army helicopters. The risks pertaining to pilots, missions and helicopters are evaluated based on bounded data, and pilots are appropriately allocated to missions and helicopters using goal programming with bounded risk scores. Using bounded data, two risk allocation models are developed to be used with the expected value and lower/upper limit values, resulting in improved reliability of the solutions. Numerical experiments show reasonable solutions and valuable information for risk management.  相似文献   
12.
It is discussed how to determine the optimal amount of storage space and the optimal number of transfer cranes for import containers. A cost model is developed for the decision making. It includes the space cost, the fixed cost of transfer cranes which corresponds to the investment cost, the variable cost of transfer cranes and outside trucks which is related to the time spent for the transfer of containers. A simple solution procedure for the optimal solution is provided. The solution procedure is illustrated using a numerical example.  相似文献   
13.
The CRISPR/Cas9 site-directed gene-editing system offers great advantages for identifying gene function and crop improvement. The circadian clock measures and conveys day length information to control rhythmic hypocotyl growth in photoperiodic conditions, to achieve optimal fitness, but operates through largely unknown mechanisms. Here, we generated core circadian clock evening components, Brassica rapa PSEUDO-RESPONSE REGULATOR (BrPRR) 1a, 1b, and 1ab (both 1a and 1b double knockout) mutants, using CRISPR/Cas9 genome editing in Chinese cabbage, where 9–16 genetic edited lines of each mutant were obtained. The targeted deep sequencing showed that each mutant had 2–4 different mutation types at the target sites in the BrPRR1a and BrPRR1b genes. To identify the functions of BrPRR1a and 1b genes, hypocotyl length, and mRNA and protein levels of core circadian clock morning components, BrCCA1 (CIRCADIAN CLOCK-ASSOCIATED 1) and BrLHY (LATE ELONGATED HYPOCOTYL) a and b were examined under light/dark cycles and continuous light conditions. The BrPRR1a and 1ab double mutants showed longer hypocotyls, lower core circadian clock morning component mRNA and protein levels, and a shorter circadian rhythm than wildtype (WT). On the other hand, the BrPRR1b mutant was not significantly different from WT. These results suggested that two paralogous genes may not be associated with the same regulatory function in Chinese cabbage. Taken together, our results demonstrated that CRISPR/Cas9 is an efficient tool for achieving targeted genome modifications and elucidating the biological functions of circadian clock genes in B. rapa, for both breeding and improvement.  相似文献   
14.
As the control over radioactive species becomes critical for the contemporary human life, the development of functional materials for decontamination of radioactive substances has also become important. In this work, a three-dimensional (3D) porous carbon monolith functionalized with Prussian blue particles was prepared through removal of colloidal silica particles from exfoliated graphene/silica composite precursors. The colloidal silica particles with a narrow size distribution were used to act a role of hard template and provide a sufficient surface area that could accommodate potentially hazardous radioactive substances by adsorption. The unique surface and pore structure of the functionalized porous carbon monolith was examined using electron microscopy and energy-dispersive X-ray analysis (EDS). The effective incorporation of PB nanoparticles was confirmed using diverse instrumentations such as X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS). A nitrogen adsorption/desorption study showed that surface area and pore volume increased significantly compared with the starting precursor. Adsorption tests were performed with 133Cs ions to examine adsorption isotherms using both Langmuir and Freundlich isotherms. In addition, adsorption kinetics were also investigated and parameters were calculated. The functionalized porous carbon monolith showed a relatively higher adsorption capacity than that of pristine porous carbon monolith and the bulk PB to most radioactive ions such as 133Cs, 85Rb, 138Ba, 88Sr, 140Ce, and 205Tl. This material can be used for decontamination in expanded application fields.  相似文献   
15.
The pH-sensitive photocatalytic system was prepared by embedding TiO2 into poly(vinyl alcohol)/poly(acrylic acid) hydrogel. Two different type TiO2/hydrogel composites, such as matrix and nanofiber, were prepared to investigate the morphological effects on the photocatalytic activity. TiO2 was distributed uniformly in the composite hydrogel and kept the original anatase structure without any structural change. The photocatalytic activity of TiO2 was evaluated based on the efficiency of photobleaching of dye. The photobleaching of dye was improved greatly as the pH was changed into basic condition and the larger surface area of hydrogel was available for TiO2 by using nanofiber supports.  相似文献   
16.
The notion of a BCK-valued function on a set is introduced, and related properties are investigated. Codes generated by BCK-valued functions are established.  相似文献   
17.
The grooved-mirror-type Fabry-Perot (GFP) oscillator was used for coherent power-combining of multiple elements in the millimeter- and submillimeter-wave region. The admittance of the Gunn diode in oscillation was measured experimentally in the millimeter-wave region to design the GFP oscillator. The gain characteristics of the diode were found at the frequencies from 42 to 48 GHz from the measured results. With this Gunn diode in the GFP resonator, oscillation was observed. The experimental results indicated that for impedance matching between the diode and the resonant cavity, the groove height must be adjusted  相似文献   
18.
In this letter, we have studied the inverted staggered thin-film transistor (TFT) using a spin-on-glass (SOG) gate insulator and a low-temperature polycrystalline silicon (poly-Si) by Ni-mediated crystallization of amorphous silicon. The p-channel poly-Si TFT exhibited a field-effect mobility of 48.2 cm2/V ldr s, a threshold voltage of -4.2 V, a gate-voltage swing of 1.2 V/dec, and a minimum off-current of < 4 times 10-13A/ mum at Vds = -0.1 V. Therefore, the gate planarization technology by SOG can be applicable to low-cost large-area poly-Si active-matrix displays.  相似文献   
19.
Virtual reality (VR) has been widely used for training, gaming, and entertainment, and the value of VR is continually increasing as a contact-free technology. For an immersive VR experience, measuring finger movements and providing appropriate feedback to the hand are as important as visual information, given the necessity of the hands for activities in daily life. Thus, a hand-worn VR device with motion sensors and haptic feedback is desirable. In this paper, a multimodal sensing and feedback glove is developed with soft, stretchable, lightweight, and compact sensor and heater sheets manufactured by direct ink writing (DIW) of liquid metal, eutectic gallium-indium (eGaIn). In the sensor sheet, ten sensors and three vibrators are embedded to measure finger movements and provide vibro-haptic feedback. The other heater sheet provides thermo-haptic sensation in accurate and rapid manner via model-based feedback control even under stretched conditions. The multimodal sensing and feedback glove allows users to feel the contact status and discriminate materials with different temperature. Performance of the proposed multimodal glove is verified under VR environments including touching and pushing two blocks of different materials and grabbing a heated metal ball submerged in hot water.  相似文献   
20.
The field emission characteristics of an oxidized porous polysilicon were investigated with different annealing temperatures. Pt/Ti, Ir, and Au/NiCr were used as surface emitter electrodes, and Pt/Ti emitter showed highly efficient and stable electron emission characteristic compared with the conventional Au/NiCr electrode. Thin Ti layer played an important role in promotion of adhesion of Pt to SiO2 surface and uniform distribution of electric field on the OPPS surface. Additionally, the Ti layer efficiently blocked the diffusion of emitter metal, which resulted in more reliable emission characteristics. Pt/Ti emitter annealed at 350 °C/1 h showed the highest efficiency of 3.36% at Vps=16 V, which resulted from the improvement of interfacial contact characteristics of thin emitter metal to an oxidized porous polysilicon. Annealing above 400 °C showed that Pt/Ti and Ir emitter electrode were thermally more stable than Au/NiCr emitter.  相似文献   
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