More than 10000 different types of ship ply the waters of Bangladesh all year round,but the performance of these ships in terms of CO2 emission is not known and regulations related to energy efficiency of inland water...More than 10000 different types of ship ply the waters of Bangladesh all year round,but the performance of these ships in terms of CO2 emission is not known and regulations related to energy efficiency of inland waterway ships remain nonexistent.This paper attempts to assess the present situation of inland class vessels in terms of Energy Efficiency Design Index(EEDI).With the use of a developed database of inland vessels in Bangladesh,EEDI reference lines for different types of inland vessels in Bangladesh were established and then compared with those of other countries.The present EEDI of existing inland vessels was investigated.Results indicate that most of the existing vessels do not meet the current EEDI baseline.Hence,new guidelines are necessary to achieve EEDI compliance in the near future.Some recommendations were proposed for improving CO2 emissions,with the socioeconomic and technical factors in Bangladesh taken into consideration.展开更多
Methods of constructing the optimum chemical balance weighing designs from symmetric balanced incomplete block designs are proposed with illustration. As a by-product pairwise efficiency and variance balanced designs ...Methods of constructing the optimum chemical balance weighing designs from symmetric balanced incomplete block designs are proposed with illustration. As a by-product pairwise efficiency and variance balanced designs are also obtained.展开更多
The digital filters with adjustable frequency-domain characteristics are called variable filters. Variable filters are useful in the applications where their characteristics are required to be changeable during the co...The digital filters with adjustable frequency-domain characteristics are called variable filters. Variable filters are useful in the applications where their characteristics are required to be changeable during the course of signal processing. Generally speaking, the variable frequency responses of a variable filters are the functions of a set of spectral parameters defining the desired frequencyUomain characteristics. In this paper, we first sample the given variable maghtode specifications and use them to construct a multi-dimensional (M - D) specification array, then propose an outer product expansion method for expanding it as the sum of the outer products of vectors. Using the outer product expansion, we can simplify the difficult problem of desighng a variable filter as the easy one that only needs constant 1 - D filter designs and 1 - D polynoIhal approximations. The method can obtain variable filters having arbitrary desired variable magnitude characteristics with a high design acctiracy.展开更多
The successful development of Li-O_2 battery technology depends on developing a stable and efficient cathode. As an important step toward this goal, for the first time, we report the development of CeO_2 nanoparticles...The successful development of Li-O_2 battery technology depends on developing a stable and efficient cathode. As an important step toward this goal, for the first time, we report the development of CeO_2 nanoparticles modified NiCo_2O_4 nanowire arrays(NWAs) grown on the carbon textiles as a new carbon-free and binder-free cathode system. In this study, the Li-O_2 battery with the CeO_2@NiCo_2O_4 NWAs has exhibited much reduced overpotentials, a high discharge capacity, an improved cycling stability,outperforming the Li-O_2 battery with NiCo_2O_4 NWAs. These improvements can be attributed to both the tailored morphology of discharge product and improved oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) activity after CeO_2 NPs deposition. To a considerable extent, this idea of cathode construction including structure design and composition optimization can provide guidance for further researches in developing more powerful cathode for Li-O_2 battery.展开更多
A barcode-like waveguide nanostructure with discretized multilevel pixel lines is designed and optimized by a nonlinear search algorithm. We obtain the design of a one-dimensional multilevel nanostructure with-1.04 d ...A barcode-like waveguide nanostructure with discretized multilevel pixel lines is designed and optimized by a nonlinear search algorithm. We obtain the design of a one-dimensional multilevel nanostructure with-1.04 d B efficiency for surface normal coupling to a standard single-mode fiber. Another design is achieved from the automatic optimization process, which enables polarization-independent coupling to a single-mode fiber. The optimum coupling efficiency is simulated to be-2.83 dB for TE and-3.49 for TM polarization centered near the 1550 nm wavelength. Polarization-dependent loss of less than 1 dB over 45.3 nm is achieved.展开更多
Under the synergistic effect of molecular design and devices engineering, small molecular organic solar cells have presented an unstoppable tendency for rapid development with putting forward donor- acceptor (D-A) s...Under the synergistic effect of molecular design and devices engineering, small molecular organic solar cells have presented an unstoppable tendency for rapid development with putting forward donor- acceptor (D-A) structures. Up to now, the highest power conversion efficiency of small molecules has exceeded 11%, comparable to that of polymers. In this review, we summarize the high performance small molecule donors in various classes of typical donor-acceptor (D-A) structures and discuss their relationships briefly.展开更多
We propose a cascade system of filters for realizing a non-uniform waveband separation for optical networks. The use of such separation is required at the DEMUX stage in a optical OXC switching wavebands. The design o...We propose a cascade system of filters for realizing a non-uniform waveband separation for optical networks. The use of such separation is required at the DEMUX stage in a optical OXC switching wavebands. The design of the system is based on optimized balanced tree, which minimizes the overall optical loss.展开更多
The development of economically feasible bio-based process requires efficient cell factories capable of producing the desired product at high titer under high-cell-density fermentation.Herein we present a combinatoria...The development of economically feasible bio-based process requires efficient cell factories capable of producing the desired product at high titer under high-cell-density fermentation.Herein we present a combinatorial approach based on systems metabolic engineering and metabolic evolution for the development of efficient biomass-producing strain.Systems metabolic engineering guided by flux balance analysis(FBA)was first employed to rationally design mutant strains of Scheffersomyces stipitis with high biomass yield.By experimentally implementing these mutations,the biomass yield was improved by 30%in GPD1,25%in TKL1,30%in CIT1,and 44%in ZWF1 overexpressed mutants compared to wild-type.These designed mutants were further fine-tuned through metabolic evolution resulting in the maximal biomass yield of 0.49 g-cdw/g-glucose,whichmatcheswell with predicted yield phenotype.The constructed mutants are beneficial for biotechnology applications dealing with high cell titer cultivations.This work demonstrates a solid confirmation of systems metabolic engineering in combination with metabolic evolution approach for efficient strain development,which could assist in rapid optimization of cell factory for an economically viable and sustainable bio-based process.展开更多
文摘More than 10000 different types of ship ply the waters of Bangladesh all year round,but the performance of these ships in terms of CO2 emission is not known and regulations related to energy efficiency of inland waterway ships remain nonexistent.This paper attempts to assess the present situation of inland class vessels in terms of Energy Efficiency Design Index(EEDI).With the use of a developed database of inland vessels in Bangladesh,EEDI reference lines for different types of inland vessels in Bangladesh were established and then compared with those of other countries.The present EEDI of existing inland vessels was investigated.Results indicate that most of the existing vessels do not meet the current EEDI baseline.Hence,new guidelines are necessary to achieve EEDI compliance in the near future.Some recommendations were proposed for improving CO2 emissions,with the socioeconomic and technical factors in Bangladesh taken into consideration.
文摘Methods of constructing the optimum chemical balance weighing designs from symmetric balanced incomplete block designs are proposed with illustration. As a by-product pairwise efficiency and variance balanced designs are also obtained.
文摘The digital filters with adjustable frequency-domain characteristics are called variable filters. Variable filters are useful in the applications where their characteristics are required to be changeable during the course of signal processing. Generally speaking, the variable frequency responses of a variable filters are the functions of a set of spectral parameters defining the desired frequencyUomain characteristics. In this paper, we first sample the given variable maghtode specifications and use them to construct a multi-dimensional (M - D) specification array, then propose an outer product expansion method for expanding it as the sum of the outer products of vectors. Using the outer product expansion, we can simplify the difficult problem of desighng a variable filter as the easy one that only needs constant 1 - D filter designs and 1 - D polynoIhal approximations. The method can obtain variable filters having arbitrary desired variable magnitude characteristics with a high design acctiracy.
基金supported by the Ministry of Science and Technology of the People’s Republic of China (2017YFA0206704, 2016YFB0100103)the National Basic Research Program of China (2014CB932300)+3 种基金Strategic Priority Research Program of the Chinese Academy of Sciences (XDA09010404)Technology and Industry for National Defence of the People’s Republic of China (JCKY2016130B010)the National Natural Science Foundation of China (51771177, 21422108, 51472232)Jilin Province Science and Technology Development Program (20160101289JC)
文摘The successful development of Li-O_2 battery technology depends on developing a stable and efficient cathode. As an important step toward this goal, for the first time, we report the development of CeO_2 nanoparticles modified NiCo_2O_4 nanowire arrays(NWAs) grown on the carbon textiles as a new carbon-free and binder-free cathode system. In this study, the Li-O_2 battery with the CeO_2@NiCo_2O_4 NWAs has exhibited much reduced overpotentials, a high discharge capacity, an improved cycling stability,outperforming the Li-O_2 battery with NiCo_2O_4 NWAs. These improvements can be attributed to both the tailored morphology of discharge product and improved oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) activity after CeO_2 NPs deposition. To a considerable extent, this idea of cathode construction including structure design and composition optimization can provide guidance for further researches in developing more powerful cathode for Li-O_2 battery.
基金National Natural Science Foundation of China(NSFC)(61505039)Shenzhen Municipal Science and Technology Plan Project(JCYJ20150403161923530)
文摘A barcode-like waveguide nanostructure with discretized multilevel pixel lines is designed and optimized by a nonlinear search algorithm. We obtain the design of a one-dimensional multilevel nanostructure with-1.04 d B efficiency for surface normal coupling to a standard single-mode fiber. Another design is achieved from the automatic optimization process, which enables polarization-independent coupling to a single-mode fiber. The optimum coupling efficiency is simulated to be-2.83 dB for TE and-3.49 for TM polarization centered near the 1550 nm wavelength. Polarization-dependent loss of less than 1 dB over 45.3 nm is achieved.
基金supported by the National Natural Science Foundation of China (Nos. 21474022, 51603051)Youth Innovation Promotion Association CAS and Beijing Nova Program (No. Z171100001117062)the Chinese Academy of Sciences
文摘Under the synergistic effect of molecular design and devices engineering, small molecular organic solar cells have presented an unstoppable tendency for rapid development with putting forward donor- acceptor (D-A) structures. Up to now, the highest power conversion efficiency of small molecules has exceeded 11%, comparable to that of polymers. In this review, we summarize the high performance small molecule donors in various classes of typical donor-acceptor (D-A) structures and discuss their relationships briefly.
文摘We propose a cascade system of filters for realizing a non-uniform waveband separation for optical networks. The use of such separation is required at the DEMUX stage in a optical OXC switching wavebands. The design of the system is based on optimized balanced tree, which minimizes the overall optical loss.
基金Platform Technology grant from National Center for Genetic Engineering and Biotechnology,Thailand(No.P-13-50084).
文摘The development of economically feasible bio-based process requires efficient cell factories capable of producing the desired product at high titer under high-cell-density fermentation.Herein we present a combinatorial approach based on systems metabolic engineering and metabolic evolution for the development of efficient biomass-producing strain.Systems metabolic engineering guided by flux balance analysis(FBA)was first employed to rationally design mutant strains of Scheffersomyces stipitis with high biomass yield.By experimentally implementing these mutations,the biomass yield was improved by 30%in GPD1,25%in TKL1,30%in CIT1,and 44%in ZWF1 overexpressed mutants compared to wild-type.These designed mutants were further fine-tuned through metabolic evolution resulting in the maximal biomass yield of 0.49 g-cdw/g-glucose,whichmatcheswell with predicted yield phenotype.The constructed mutants are beneficial for biotechnology applications dealing with high cell titer cultivations.This work demonstrates a solid confirmation of systems metabolic engineering in combination with metabolic evolution approach for efficient strain development,which could assist in rapid optimization of cell factory for an economically viable and sustainable bio-based process.