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This research proposes to evaluate and analyze the decision matrix for learner's English mobile applications (EMAs) based on multi-objective heuristic decision making with a view to listening, speaking, reading, and writing. Because of the number of criteria, the significance of parameters, and variance in results, EMAs are difficult. Decision making has built on the combination of listening, speaking, reading, and writing and EMA evaluation criteria for students. The requirements are adapted from a framework of pre-school education. Six alternatives and 17 skills as a requirement are included in decision-making results. The six EMA are then assessed, with six English learning experts distributing a review form. The application subsequently is evaluated using the best-worst method and preference-order technique (TOPSIS) using multi-objective heuristic decision making methods. The best-worst method is used to measure requirements, whereas TOPSIS is used to test and assess the applications. In two cases, namely person and group, TOPSIS is used. Internal and external aggregations are used throughout the group context. In effect, the aim of evaluating the proposed study and comparing it to six relative studies with scenarios and benchmarking checklists is to develop an objectives validation framework for e-apps.

Chronic stress-induced brain injury (CSBI) is the organic damage of brain tissue caused by long-term psychological and environmental stress. However, there is no effective drug for the treatment of CSBI. The present study aimed to investigate possible mechanisms of CSBI and to explore related therapeutic targets. A rat model of CSBI was established by combining chronic restraint and cold water immersion. Our CSBI model was validated via Nissl staining, Western blotting, and behavioral tests. RNA sequencing (RNA-seq) was used to identify differentially expressed genes (DEGs) within brain tissue during CSBI. Both Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses were performed to determine signaling pathways associated with CSBI-induced DEGs. Agonists/antagonists were used to validate the pharmacodynamics of potential therapeutic targets. A combination of chronic restraint and cold water immersion successfully induced a rat model of CSBI, as indicated by various markers of brain injury and cell apoptosis that were verified via Nissl staining, Western blotting, and behavioral tests. RNA-seq analysis identified 1,131 DEGs in CSBI rats. Of these DEGs, 553 genes were up-regulated and 778 genes were down-regulated. GO and KEGG pathway analyses revealed that significant DEGs were predominantly related to membrane-bound ion channels, among which the potassium channel function was found to be significantly affected. Pharmacological experiments revealed that retigabine, a voltage-gated potassium channel opener, demonstrated a protective effect in CSBI rats. Taken together, our findings suggest that potassium channel function is disrupted in CSBI, and that potassium channel regulators may function as anti-CSBI drugs.

In this paper, we compared the domestic and foreign research situation in the field of genomics from the perspective of bibliometrics, aiming to provide some references for further study. We retrieved genomics related literature through the Web of Science and CNKI from 1985 to 2016, and then analyzed the number of published articles, the networks of collaboration among authors, research institutes and countries, the co-occurrence of keywords and co-citations of the retrieved literature through the software CiteSpace 4.0.R5 SE. The number of published periodical articles develops in fluctuation and shows a rising trend in general. The USA holds the largest share of world publications in genomics, the following is the UK and China in order. A core institution with considerable scale has formed in America and good cooperative relationships have been established between universities in the institution. Chinese Academy of Sciences is the main research institution in China. The cooperation between the international institutions is more often and closer than that at home. The researchers with the most articles published in Chinese and foreign journals are Liu J.Q. and Zhang Y respectively. The main co-occurrence and burst keywords are Pharmacogenomics, Functional genomics, Comparative genomics, Proteomics, etc. The articles with the highest centrality, highest citation frequency and highest burst strength are (Yang, 2007), (Lander, 2001) and (Altschul, 1997), respectively. Interagency cooperation should be enhanced so as to push forward the development of genomics research in China.

Optimization of fan-out energy distribution for substrate guided wave optical interconnects with a surface-normal configuration is addressed in this paper. Up to nine optimized waveguide holograms are independently fabricated on the same substrate. Energy fluctuation affected by the deviation of the designed diffraction efficiency is theoretically analysed. Using DuPont photopolymer film HRF-600X001-20, we demonstrate 1-to-5 and 1-to-9 surface-normal fan-out devices operating at 850 nm. The output non-uniformities of ±4% and ±10% are experimentally confirmed for the two devices, respectively.

The film shrinkage effect of photopolymeric phase media failed to provide the desired volume holograms for point-to-point optical interconnects. In this letter, we report a compensation method to physically correct the shrinkage effect that resulted from the holographic recording and the postbaking. Dupont photopolymer HRF-600X001 is studied. The correction of the Bragg diffraction angle shift of 1°21′, which is induced by a 5.25% film shrinkage, is successfully demonstrated with the surface-normal configuration. A shrinkage-corrected volume hologram with 80% diffraction efficiency is experimentally confirmed. The methodology reported herein is applicable to other phase media when the associated film shrinkage data are experimentally determined.

The vulnerability in optoelectronic packaging of free space optical interconnects fail to provide a reliable interconnection for highly parallel system. In this letter, we report, for the first time, a substrate-guided-wave-based perfect shuffle (PS) having an 8-to-8 interconnection, is demonstrated at 632.8-nm wavelength. Sixteen waveguide holograms are fabricated with the full functionality of the PS. The diffraction efficiencies of the waveguide holograms are all within 80%/spl plusmn/5%, The surface-normal configuration of the demonstrated PS makes the integration with vertical-cavity surface-emitting lasers (VCSELs) and other surface-mountable processing elements (PEs) highly feasible.

A dual-core baseband processor IC for GSM/GPRS cellular phone applications is built in a 0.13 /spl mu/m CMOS process with 5 levels of copper interconnect and contains a high level of mixed-signal integration which includes: 1 GHz CMOS synthesizer, 10 b general-purpose ADC, two 14 b ADCs, power amplifier controller, and 13 b voice codec.

We report the first bidirectional optical backplane bus for a high performance multiprocessor system operating at wavelengths of 632.8 nm and 1300 nm. The optical backplane employs an array of multiplexed holograms, in conjunction with a waveguiding plate within which cascaded fanouts are generated. Data transfer rate of 1.2 Gbit/sec at 1300 nm is demonstrated with a single bus line for a system composed of nine processor/memory boards. To provide a reliable system, packaging-related issues, such as the detector size and misalignment effects are addressed. Theoretical treatment to minimize fluctuations among the received power at each processor/memory board is further presented and an optimum design rule is provided. The backplane demonstrated here is for general-purpose. It can support standard multiprocessor buses such as Futurebus+, Multibus II, etc. It also can function as a backplane bus in existing computing systems and significantly reduce the bottlenecks that accompany electrical interconnects.

In order to utilize the high speed of optical interconnects and overcome the latencyproblem of a large bus structure, we proposed an architecture of optoelectronic hierarchical bus system. Waveguide hologram implementations, and its associated cache coherence problem are addressed. In our configuration, bus hierarchy is controlled with electronic programmable plates. Optical signals can be transmitted on all-optical paths without intermediate conversions.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The design and architecture of bi-directional optical backplanes with single and multiple bus lines for high performance bus are reviewed and bus systems with one and 2-bus lines at a wavelength of 850 nm are experimentally demonstrated. For optical backplanes with single-bus line, a speed of 1.2 Gbit/sec at a wavelength of 1,3 µm is demonstrated. Arrays of multiplexed holograms are employed, in conjunction with a waveguiding plate within which cascaded fanouts are generated. For the backplane bus system containing multiple bus lines and 9 processor/memory boards, VCSELs (Vertical Cavity Surface Emitting Lasers) and photodetector arrays, such parameters as power budget, misalignment and packaging related issues are discussed. With the introduction of GRIN lenses into the backplane system, it is found that not only can the signal beam from the VCSELs get collimated, but die angular tolerance of the system is greatly enhanced. The optical backplane bus system developed here is transparent to higher level bus protocols, thus can support standard backplane buses such as Futurebus+, Multi-bus II, and VMEbus.

microelectronic integrated circuits is limited by electromagnetic interference, parasitic capacitance, andinductance coupling. To overcome the bottlenecks of electrical interconnects, optical interconnection hasbeen widely agreed to be one of the most important alternatives.23Many investigators have been working on optical implementation of the perfect shuffle, and severalapproaches have been proposed and then demonstrated.4-9 Lohmann and his colleague4'5 performed thisconcept with a combination of lenses and prisms. Using microlens arrays, the PS is demonstrated bySawchuk and Glaser.6 Recently, holographic optical elements (HOEs) are employed to implement one-dimensional (1-D) and two-dimensional (2-D) PSs.79 All these implementations are limited to free spaceoptical interconnects, which are vulnerable to mechanical and environmental perturbations. Furthermore

The architectural design and performance of bi-directional optical backplanes with multi-bus lines are presented and analyzed. Previously, we have reported a general purpose bi- directional optical backplane with single bus line. With the integration of vertical-cavity surface-emitting lasers and photodetector arrays, in this paper, we further propose and demonstrate an optical backplane with multi-bus lines. With the multi-bus line structure, the bandwidth of the bus system is greatly increased. The performance related issue, such as the power budget consideration, the misalignment, etc., are also discussed, and related experiments are presented.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The structure, fabrication, and theory of a three-dimensional planarized optoelectronic clock signal distribution device, based on a thin light-guiding substrate in conjunction with a two-dimensional polymer holographic grating array, are described. We have demonstrated previously a 25-GHz 1-to-42 (6 x 7) highly parallel fan-out interconnect with a signal-to-noise ratio of 10 dB. We present theoretical research that focuses on generating a globally uniform fan-out distribution. An objective function aimed at equalizing the intensities among the fan-out beams is established. For an arbitrary M x N fan-out distribution, there are M + N + 1 sets of holograms needed to be recorded independently to provide the required equal fan-outs. The efficiency of each hologram is determined precisely. The angular misalignment, wavelength dispersion, and spot-size problems are discussed further, together with their tolerance requirements on the size of the photoreceivers integrated on the multichip modules. Employment of 0.25-pitch gradient index (GRIN) lenses as a collimator and as a focusing element is demonstrated experimentally. Optical beam profile manipulation and packaging tolerance are enhanced greatly with GRIN lenses. Finally, clock skew problems associated with the proposed system are discussed, and schemes to minimize the skew are proposed.

In this paper, concerning with the practical applications of substrate guided wave optical interconnects, one-to-many surface-normal fanout devices with equalized fanout energy distribution are addressed and then demonstrated. DuPont photopolymer film HRF-600X001-20 is used in our experiment. The optimum recording beam intensity is investigated for obtaining large dynamic region of diffraction efficiency versus exposure dosage. Based on the experimental diffraction efficiency curve, 1-to-5 and 1-to-9 surface- normal fanout devices are fabricated operating at a wavelength of 850 nm. Output energy fluctuations of +/- 4 percent and +/- 10 percent are obtained for the two devices.

A ne optical interconnect architecture for a 3D switch array using multiple LiNbO3-based electro-optically modulated gratings in conjunction with substrate guided waves is reported. First the operating mechanism of the system is studied in detail, and the momentum mismatch in the operating process of the system is also demonstrated. Then, a new method for calculating coupling efficiency is derived by introducing a compensation for the mismatch. With the new calculation method and by introducing a substrate guided wave with 45 degree bouncing angle and 100-V applied voltage, an optimized coupling efficiency is obtained even though it is under the case of momentum-mismatch. Finally, the experimental result of coupling efficiency of the electro-optically modulated grating is provided, and agreements between the experimental results and the theoretical prediction are obtained.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The film shrinkage effect of photopolymeric phase media failed to provide the desired volume holograms for point-to- point optical interconnects. In this paper, we report a new compensation method to physically correct the shrinkage effect resulted from the holographic recording and the post baking. DuPont photopolymer HRF-600X001 is studied. The correction of the Bragg diffraction angle shift of 85', which is induced by a 5.25 percent film shrinkage, is successfully demonstrated with the surface-normal configuration. A shrinkage-corrected volume hologram with 80 percent diffraction efficiency is experimentally confirmed. The methodology reported herein is applicable to other phase media when the associated film shrinkage data are experimentally determined.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We report on a new optical interconnect architecture for three-dimensional, multiple electro-optic gratings with LiNbO(3) used in conjunction with substrate guided waves. First the operating mechanism of the system is studied in detail, and the momentum mismatch in the operating process of the system is also demonstrated. We then derive a new method for calculating coupling efficiency by introducing a compensation for the mismatch. This theoretical research allows the new optical interconnect architecture to provide a higher design accuracy and an optimized coupling efficiency, even though it is under the case of momentum mismatch. We achieve this result by introducing a substrate guided wave with 45 degrees bouncing angle and 100-V applied voltage. The successful design and its theoretical analysis will be helpful for research on the grating coupler.

Over the past decade, the demand for more computing power has increased to such an extent that no single processor can provide the solutions in many applications. As a result, various efforts were made to build multiprocessor systems. Among those, systems based on electrical backplane buses, as shown in Fig. 1, have been prevailing in the commercial market mainly due to the ease of design and low cost. However, as the signal speed increases along the backplane, the transmission line effects become dominant, and the bus performance becomes limited by backplane physics1,2. Although advanced buses like Futurebus+3 guarantee an incident wave switching, other inherent problems degrade the performance significantly4. As new faster processors arise, the electrical backplane buses can no longer supply the bandwidth required for high performance multiprocessor systems.

In this paper, we report the implementation of waveguide-based holograms for several on-going applied photonics research at the Microelectronics Research Center of the University of Texas, Austin. These include a wavelength division demultiplexer (WDDM), a nonblocking wavelength-selective crossbar, an IEEE protocol compatible optical backplane bus and true-time-delay lines for wide-band phased array antennae. The exclusive characteristics of waveguide holograms and the maturity of photopolymeric materials make the reported research findings highly attractive for system integration where device performance features and system reliability are pivotal. The surface-normal configuration of both the WDDM and the wavelength-selective crossbar provides not only a much more rugged packaging due to the elimination of edge coupling but also an insertion compatibility with vertical cavity surface emitting laser integration. An eight channel wavelength division demultiplexing device with a center wavelength of 772 nm and a wavelength separation of 4 nm is demonstrated with channel to channel cross talk of less than -20 dB is experimentally confirmed in Section 2. A 3x3 crossbar with Δλ=10nm with a center wavelength of 765 nm is delineated in Section 3. An optical backplane bus containing nine memory/process boards with 72 interconnects is reported in section 4. A waveguide hologram based true-time-delay-line is presented in Section 5.

We review the recent results on the design and implementation of the performance-optimized bidirectional optical backplane bus aimed at high speed multiprocessor systems. It employs an array of multiplexed holograms, in conjunction with a waveguiding plate within which cascaded fanouts are generated. Data transfer rate of 1.2 Gbit/sec at 1300 nm is demonstrated with a single bus line for a system composed of nine boards. Packaging-related issues and misalignment effects are addressed. Theoretical treatment to minimize fluctuations among the received powers at each board was carried out and the overall performance was optimized. We also introduce a hybrid optical backplane with multiple bus lines. The hybrid backplane maintains the same waveguiding structure, and exploits optoelectronic array devices. A new demonstration system is being implemented. The optical backplane that we developed is transparent to higher level bus protocols, thus can support standard backplane buses such as Futurebus+, Multibus II, and VMEbus.

The structure, fabrication, and theory of a 3D planarized optoelectronic clock signal distribution device, based on a thin light-guiding substrate in conjunction with a 2D polymer holographic grating array, are described. We have previously demonstrated a 25 GHz 1-to-42 (6 X 7) highly parallel fanout interconnect with a signal to noise ration of 10 dB1. In this paper, theoretical work focused on generating a globally uniform fanout distribution is presented. An objective function aimed at equalizing the intensities among the fanout beams is established and optimization results are reported. Finally, the angular misalignment and wavelength dispersion problem are further discussed, together with their tolerance requirements on the size of the photoreceivers and the bandwidth of the vertical cavity surface emitting lasers integrated on the multi-chip-modules.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We report for the first time a bi-directional optical backplane bus for a high performance system containing nine multi-chip module (MCM) boards. The backplane bus reported herein employs arrays of multiplexed polymer-based waveguide holograms in conjunction with a waveguiding plate within which 16 substrate guided waves for 72 (8 X 9) cascaded fanouts are generated. Data transfer of 1.2 Gbit/sec at 1.3 micrometers wavelength is demonstrated for a single bus line with 72 cascaded fanouts. Packaging-related issues such as transceiver size and misalignment are embarked upon to provide a reliable system with a wide bandwidth coverage. The backplane bus demonstrated is for general-purpose and, therefore, compatible with such IEEE standardized buses as VMEbus, Futurebus, and FASTBUS, and can function as a backplane bus in existing computing environments and significantly reduce the bottlenecks that accompany electrical interconnects.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper, we report on a 5-channel wavelength division demultiplexer (WDDM) using substrate-guided waves in conjunction with a polymer-based Littrow hologram operating at 700, 710, 720, 730, and 740 nm, respectively. An average cross talk of -40 dB between adjacent channels is measured. The diffraction efficiencies of 69%, 78%, 83%, 77%, and 69% are both experimentally and theoretically confirmed for the five-channel WDDM device. Further study aiming at reducing the wavelength channel separation to 1 nm is also provided for future work. A device length of 6.4 cm corresponding to a propagation distance of 9.05 cm is required to achieve such a goal.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Optimized design for a bi-directional optical backplane bus, containing 72 (9 X 8) interconnects and employing arrays of multiplexed polymer-based waveguide holograms on a waveguiding plate, is presented in this paper. After an objective function for the system is established, the fan-out intensity fluctuations among all the different channels are minimized by solving a set of non-linear equations numerically. Particularly, the fan-out distribution for the case in which nine boards on one side of the optical bus are optimized. A global optimized diffraction efficiency distribution exits and the minimum fan-out intensity after optimization is 1.5% of the incident power.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The packing density of a highly parallel free-space multi-stage optical interconnect network involving arrays of vertical cavity surface-emitting lasers (VCSELs), microlenses, and photodetectors is analyzed for the first time, based on a crosstalk model involving the diffraction-induced crosstalk among pixels. Variations of channel packing density, interconnection distance, and optical transmission efficiency are evaluated to provide optimum design parameters for the arrays of VCSELs, microlenses, and photodetectors. It is shown that it is pivotal to optimize the photodetector diameter in such an optical interconnect network. Photodetector array misalignment effects on system performance are further investigated, providing both transverse and longitudinal alignment tolerance. Several experiments are also conducted to verify the theory developed herein.

Fabrication of the bidirectional optical backplane bus, employing arrays of multiplexed polymer-based waveguide holograms on a waveguiding plate, is reviewed. An analysis of its functionality is presented for the first time. After an objective function for the system is established, the fan-out intensity fluctuations among all the different channels are minimized by solving a set of nonlinear equations numerically. To further ensure the validity of our calculation, a different objective function is considered and the same optimized result is obtained. Particularly, we optimized the fan-out distribution for the case in which nine boards on one side of the optical bus are presented. It was found that a globally optimized diffraction efficiency distribution exists and the minimum fan-out intensity after optimization is about 1.5% of the incident power, which means a minimum laser diode power for this bidirectional optical bus has to be above 7.0 mW for a system speed of 1.2 Gbit/s and a bit error rate of 10-15. Finally, the surface normal fanout beams come out of both directions of the backplane. Therefore, the best hardware implementation scheme integrates the processor/memory boards on both sides of the backplane bus. As a result, the optimal member of processor/memory boards is 16, i.e., 9 ± (922), rather than 9.