Map / envelope based design process of the planetary roller screw

Electro-Mechanical linear actuators have received recent attention for the aircraft control surface systems to eliminate hydraulic systems from aircraft. This approach is intended to improve reliability, safety, efficiency, and maintainability. For linear actuators, one of the most important components is the planetary roller screws (PRSs). The planetary roller screw (also called the satellite roller screw) is a mechanical transmission device, which converts rotational motion to linear motion or vice versa. The mechanism of planetary screw is similar in principle to the conventional ball screw mechanism (BSM). PRS has been receiving attention in lots research and industry, however, it is hard to produce high-quality PRS transmissions, because it is difficult to determine the PRS parameter relationship among all its components and hard to build visual maps for rapid design. The main objective of this research is to provide the parametric relationship between components to build design maps. Developing a visual design process for PRSs is the primary goal. In order to understand contact geometry and relative motions in the PRS, an exact PRSs structure is presented, as well as its parameter analysis. Then the parameters are tested to identify how the parameters affect the PRSs requirements such as load distribution, stiffness, dynamic load capacity, and force density as key measures for the visual design process. One of the key impacts of this research is the utilization of design procedures to build sets of 3-D design maps. These maps and design procedures are helpful to manage parameters to quickly build optimal PRSs dimensions for designers. Each measure has its own parameters. Some of these parameters are fixed constants and others can be set by designer. As variables, the parameters are classified into two types. Ones are primary parameters that have large impact on the mapping and design process and others are secondary parameters that have minor impact. Any set of parameters is given in accordance with each set of 3-D maps and they can be adjusted to generate new visual 3-D maps by designer. Then the designer can reviews the 3-D mapping results, he or she can then quickly decide the effect of first design decision and adjust updated parameter choices to get new maps. This helps the designer to optimize dimensions of PRSs and determine the best solution for application requirements by this design process. Overall, the whole design process accelerates quickly reaching the design goal for the designerMechanical Engineerin

Optimized Data Rate Allocation for Dynamic Sensor Fusion over Resource Constrained Communication Networks

This paper presents a new method to solve a dynamic sensor fusion problem. We consider a large number of remote sensors which measure a common Gauss-Markov process and encoders that transmit the measurements to a data fusion center through the resource restricted communication network. The proposed approach heuristically minimizes a weighted sum of communication costs subject to a constraint on the state estimation error at the fusion center. The communication costs are quantified as the expected bitrates from the sensors to the fusion center. We show that the problem as formulated is a difference-of-convex program and apply the convex-concave procedure (CCP) to obtain a heuristic solution. We consider a 1D heat transfer model and 2D target tracking by a drone swarm model for numerical studies. Through these simulations, we observe that our proposed approach has a tendency to assign zero data rate to unnecessary sensors indicating that our approach is sparsity promoting, and an effective sensor selection heuristic

Closely Mounted Compact Wideband Diversity Antenna for Mobile Phone Applications

Here a compact wideband diversity antenna covering the PCS/UMTS/WiMAX bands with high isolation and low enveloped correlation coefficient (ECC) is proposed. To widen the bandwidth, the proposed antenna uses a structure with a gap-coupled feed and an inductively shorted line that has capacitive compensation between the radiator and the ground plane. Also, a suspended line with a parasitic element is used to enhance the isolation between the two antennas

Closely Mounted Compact Wideband Diversity Antenna for Mobile Phone Applications

Here a compact wideband diversity antenna covering the PCS/UMTS/WiMAX bands with high isolation and low enveloped correlation coefficient (ECC) is proposed. To widen the bandwidth, the proposed antenna uses a structure with a gap-coupled feed and an inductively shorted line that has capacitive compensation between the radiator and the ground plane. Also, a suspended line with a parasitic element is used to enhance the isolation between the two antennas

The Draft Genome of an Octocoral, Dendronephthya gigantea

Coral reefs composed of stony corals are threatened by global marine environmental changes. However, soft coral communities of octocorallian species, appear more resilient. The genomes of several cnidarians species have been published, including from stony corals, sea anemones, and hydra. To fill the phylogenetic gap for octocoral species of cnidarians, we sequenced the octocoral, Dendronephthya gigantea, a nonsymbiotic soft coral, commonly known as the carnation coral. The D. gigantea genome size is similar to 276 Mb. A high-quality genome assembly was constructed from PacBio long reads (29.85 Gb with 108x coverage) and Illumina short paired-end reads (35.54 Gb with 128x coverage) resulting in the highest N50 value (1.4 Mb) reported thus far among cnidarian genomes. About 12% of the genome is repetitive elements and contained 28,879 predicted protein-coding genes. This gene set is composed of 94% complete BUSCO ortholog benchmark genes, which is the second highest value among the cnidarians, indicating high quality. Based on molecular phylogenetic analysis, octocoral and hexacoral divergence times were estimated at 544 MYA. There is a clear difference in Hox gene composition between these species: unlike hexacorals, the Antp superclass Evx gene was absent in D. gigantea. Here, we present the first genome assembly of a nonsymbiotic octocoral, D. gigantea to aid in the comparative genomic analysis of cnidarians, including stony and soft corals, both symbiotic and nonsymbiotic. The D. gigantea genome may also provide clues to mechanisms of differential coping between the soft and stony corals in response to scenarios of global warming

Transcriptional regulatory networks of tumor-associated macrophages that drive malignancy in mesenchymal glioblastoma.

BACKGROUND: Glioblastoma (GBM) is a complex disease with extensive molecular and transcriptional heterogeneity. GBM can be subcategorized into four distinct subtypes; tumors that shift towards the mesenchymal phenotype upon recurrence are generally associated with treatment resistance, unfavorable prognosis, and the infiltration of pro-tumorigenic macrophages. RESULTS: We explore the transcriptional regulatory networks of mesenchymal-associated tumor-associated macrophages (MA-TAMs), which drive the malignant phenotypic state of GBM, and identify macrophage receptor with collagenous structure (MARCO) as the most highly differentially expressed gene. MARCO CONCLUSIONS: Collectively, our study characterizes the global transcriptional profile of TAMs driving mesenchymal GBM pathogenesis, providing potential therapeutic targets for improving the effectiveness of GBM immunotherapy