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排序方式: 共有275条查询结果,搜索用时 281 毫秒
91.
Rim Kalaï Daniel Vanderpooten 《International Transactions in Operational Research》2011,18(1):103-113
The knapsack problem is a classical combinatorial optimization problem used to model many industrial situations. The robust version of this problem was studied in the literature using a max–min or min–max regret criterion. In this paper, we show the drawbacks of such criteria and propose a new robustness approach, called lexicographic α‐robustness. We show that the complexity of the lexicographic α‐robust problem does not increase compared with the max–min version and present a pseudo‐polynomial algorithm in the case of a bounded number of scenarios. 相似文献
92.
Developing and Evaluating New ICT Innovation System: Case Study of Korea's Smart Media Industry
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The smart media (SM) industry has demonstrated that it has the characteristics to increase user innovative activities, enhance open innovativeness, and increase the segmentation of innovation value. This study introduces and evaluates an innovation system that reflects the characteristics of the SM industry. We categorize the SM industry into hardware, network, platform, and content industries and perform an AHP analysis (based on a survey of 96 experts) to evaluate the relative importance of the factors/factor groups affecting the creation of innovation. The results show that “collaboration activity” is a more important factor than other innovation factor groups (financial support, R&D, policy environment, human resources) in the SM industry. The results also show that the important factors/factor groups differ by industry. 相似文献
93.
Maria Lisa Clodoveo Rim Hachicha Hbaieb Faten Kotti Giacomo Scarascia Mugnozza Mohamed Gargouri 《Comprehensive Reviews in Food Science and Food Safety》2014,13(2):135-154
This monograph is a critical review of the biological activities that occur during virgin olive oil (VOO) extraction process. Strategic choices of plant engineering systems and of processing technologies should be made to condition the enzymatic activities, in order to modulate the nutritional and the sensory quality of the product toward the consumer expectations. “Modulation” of the product quality properties has the main aim to predetermine the quantity and the quality of 2 classes of substances: polyphenols and volatile compounds responsible of VOO nutritional and sensory characteristics. In the 1st section, a systematic analysis of the literature has been carried out to investigate the main olive enzymatic activities involved in the complex biotransformation that occurs during the mechanical extraction process. In the 2nd section, a critical and interpretative discussion of the influence of each step of the extraction process on the polyphenols and the volatile compounds has been performed. The effect of the different mechanical devices that are part of the extraction process is analyzed and recommendations, strategies, and possible avenues for future researches are suggested. 相似文献
94.
Lee SJ Koo JR Lim DH Park HR Kim YK Ha Y 《Journal of nanoscience and nanotechnology》2011,11(8):7151-7154
We demonstrated efficient and stable white phosphorescent organic light-emitting diodes (OLEDs) with double-emitting layers (D-EMLs), which were comprised of two emissive layers with a hole transport-type host of N,N'-dicarbazolyl-3,5-benzene (mCP) and a electron transport-type host of 2,2',2"-(1,3,5-benzenetryl)tris(1-phenyl)-1H-benzimidazol (TPBi) with blue/orange emitters, respectively. We fabricated two type white devices with single emitting layer (S-EML) and D-EML of orange emitter, maintaining double recombination zone of blue emitter. In addition, the device architecture was developed to confine excitons inside the D-EMLs and to manage triplet excitons by controlling the charge injection. As a result, light-emitting performances of white OLED with D-EMLs were improved and showed the steady CIE coordinates compared to that with S-EML of orange emitter, which demonstrated the maximum luminous efficiency and external quantum efficiency were 21.38 cd/A and 11.09%. It also showed the stable white emission with CIE(x,y) coordinates from (x = 0.36, y = 0.37) at 6 V to (x = 0.33, y = 0.38) at 12 V. 相似文献
95.
To improve power factor and to meet IEC 555-2 harmonic requirements, input power factor correction circuits have been used, widely, in the power supply industry. In response to the trend, this study proposes and investigates a simple controller for a single-phase AC to DC rectifier with input power factor correction 相似文献
96.
Jun Rim Choi Lak Hyun Jang Seong Wook Jung Jin Ho Choi 《Solid-State Circuits, IEEE Journal of》1997,32(3):468-476
A compact 10-b, 288-tap finite impulse response (FIR) filter is designed by adopting structured architecture that employs an optimized partial product tree compression method. The new scheme is based on the addition of equally weighted partial products resulted from 288 multiplications of the filter coefficients and the inputs. The 288 multiplication and 287 addition operations are decomposed to add 1440 partial products and the sign extension operations are manipulated independently to ensure the operation at 72 MHz, the internal clock frequency generated by the integrated phase-locked loop (PLL) clock multiplier. In addition to the optimized transmission gate full adder, modified carry save compression circuits such as 4:2 and 5:5:2 compressors are used to perform decomposed partial product addition. This structured approach enables cascade design that requires more than 288-tap FIR filtering. The completed 288-tap FIR fitter core occupies 5.36×7.29 mm2 of silicon area that consists of 371732 transistors in 0.6-μm triple-metal CMOS technology, and it consumes only 0.8 W of average power at 3.3 V 相似文献
97.
98.
Takagi S. Hoyt J.L. Rim K. Welser J.J. Gibbons J.F. 《Electron Devices, IEEE Transactions on》1998,45(2):494-501
In this study, admittance spectroscopy is applied for the first time to MOS capacitors fabricated on Si/Si1-xGex/Si double-heterostructures, in order to evaluate the valence band discontinuity ΔEv at the Si/Si1-xGex interface. The principle of the measurement is presented and verified by the experimental results. A new feature of admittance spectroscopy applied to MOS capacitors is the ability to select the interface whose barrier is measured, by controlling the gate voltage. This fact is confirmed by the measurement of MOS capacitors, which include a SiGe well with different Ge contents at the front and the back interfaces. It is found from this measurement that, while ΔEv at the back interface of the double-heterostructure is measured under slight depletion conditions for MOS capacitors, ΔEv averaged between the front and the back interfaces is measured under accumulation conditions. The Gex content dependence of the measured ΔEv is found to be in fairly good agreement with the theoretical values 相似文献
99.
Baseline concentrations of prolactin (PRL) was determined in the CSF of 28 lobotomized and 28 non-lobotomized patients with chronic schizophrenia. The mean PRL level of the female patients was significantly higher than that of the male patients (p < 0.001). In addition, non-lobotomized patients had significantly higher concentrations of CSF PRL than patients of the lobotomized group (p < 0.05). On the other hand, patients belonging to the latter group exhibited significantly more central as well as cortical brain atrophy than the patients on whom no psychosurgery had been performed (0.05 > p < 0.001). The significance of cerebrospinal PRL as an index of central dopamine metabolism is discussed. 相似文献
100.
A recently proposed circuit P-Q transformation is used to analyze a three-phase controlled-current PWM rectifier. The DC operating point and AC transfer functions are completely determined. Most features of the power converter are clearly interpreted. They are: (1) the output voltage can be controlled from zero to maximum; (2) the system is equivalently an ideal current source in the steady state; (3) the system can be described as linear circuits; and (4) the input power factor can be arbitrarily controlled within a certain control range 相似文献