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Deploying teams of cooperative unmanned aerial vehicles (UAVs) to harvest data from distributed Internet of Things (IoT) devices requires efficient trajectory planning and coordination algorithms. Multi-agent reinforcement learning (MARL) has emerged as an effective solution, but often requires extensive and costly real-world training data. In this paper, we propose a novel model-aided federated MARL algorithm to coordinate multiple UAVs on a data harvesting mission with limited knowledge about the environment, significantly reducing the real-world training data demand. The proposed algorithm alternates between learning an environment model from real-world measurements and federated QMIX training in the simulated environment. Specifically, collected measurements from the real-world environment are used to learn the radio channel and estimate unknown IoT device locations to create a simulated environment. Each UAV agent trains a local QMIX model in its simulated environment and continuously consolidates it through federated learning with other agents, accelerating the learning process and further improving training sample efficiency. Simulation results demonstrate that our proposed model-aided FedQMIX algorithm substantially reduces the need for real-world training experiences while attaining similar data collection performance as standard MARL algorithms., 7 pages, 2 figures

Cell-type-specific use of the same DNA blueprint generates diverse cell types. Such diversity must also be executed via differential deployment of the same subcellular machinery. However, our understanding of the size, distribution, and dynamics of subcellular machinery in native tissues, and their connection to cellular diversity, remain limited. We generate and characterize an inducible tricolor reporter mouse, dubbed “kaleidoscope”, for simultaneous imaging of lysosomes, mitochondria and microtubules in any cell type and at a single cell resolution. The expected subcellular compartments are labeled in culture and in tissues with no impact on cellular and organismal viability. Quantitative and live imaging of the tricolor reporter captures cell-type-specific organelle features and kinetics in the lung, as well as their changes after Sendai virus infection.Yap/Tazmutant lung epithelial cells undergo accelerated lamellar body maturation, a subcellular manifestation of their molecular defects. A comprehensive toolbox of reporters for all subcellular structures is expected to transform our understanding of cell biology in tissues.SUMMARY STATEMENTOur understanding of subcellular machinery is often inferred from that in cultured cells. Hutchison et al. have generated a tricolor tunable reporter mouse for simultaneous imaging of lysosomes, mitochondria and microtubules in the native tissues at a single-cell resolution.

Chitosan adhesive hydrogels have attracted interest because of their unique properties. However, it is still a challenge to use simple and unmodified chitosan to synthesize multifunctional hydrogels with adhesive, self-healing and strain sensing properties. Here, a multifunctional hydrogel of Ca

Stereoselective synthesis of (Z)-α-boryl-crotylboronate is developed., Stereoselective synthesis of (Z)-α-boryl-crotylboronate is developed. Ni-catalyzed Z-selective alkene isomerization of α-boryl substituted homoallylboronate provided the targeted (Z)-crotylboronate with high selectivity. Stereoselective addition of the novel crotylboron reagent to aldehydes gave (E)-δ-boryl-substituted syn-homoallylic alcohols with excellent diastereoselectivities. The vinyl boronate unit in the products can be directly used for a subsequent C–C bond-forming transformation as illustrated in the synthesis of the C1–7 fragment of the natural products nannocystin A and nannocystin Ax.

Diastereoselective synthesis of γ-boryl substituted syn-β-alkoxy- or syn-β-amino-homoallylic alcohols is developed. Pt-catalyzed regioselective diboration of alkoxyallene or aminoallene with B2pin2 occurred at the terminal alkene unit of the allene to give ( Z)-γ-alkoxy- or ( Z)-γ-amino-β-boryl substituted allylboronates with high selectivities. Addition of the allylboronates to aldehydes followed by protection of the resulting secondary hydroxyl group gave TES-protected syn-1,2-diols and syn-1,2-amino alcohols with high diastereoselectivities. The vinyl-Bpin group in the products is a useful handle for further transformations.

A series of novel furoxan-based NO-donating b-elemene hybrids were designed and synthesized to improve the anticancer efficacy of natural b-elemene. The bioassay results indicated that all of the target compounds exhibited significantly improved antiproliferative activities against three cancer cell lines (SGC-7901, HeLa and U87) compared to parent compound b-elemene. Interestingly, these compounds displayed excellent sensitivity to U87 cells with IC50 values ranging from 173 to 2 nM. Moreover, most compounds produced high levels of NO in vitro, and the antitumor activity of 11a in U87 cells was markedly attenuated by an NO scavenger (hemoglobin or carboxy-PTIO). Further mechanism studies revealed that 11a caused the G2 phase arrest of the cell cycle and induced apoptosis of U87 cells by preventing the activation of the PI3K/Akt pathway. Moreover, 11a significantly suppressed the tumor growth in H22 liver cancer xenograft mouse model with a tumor inhibitory ratio (TIR) of 64.8%, whichwas superior to that of b-elemene (TIR, 49.6%) at the same dose of 60 mg/kg. Together, the remarkable biological profiles of these novel NO-donating b-elemene derivatives may make them promising candidates for the intervention of human cancers.

A series of novel ?-elemene isopropanolamine derivatives were synthesized and evaluated for their antitumor activity. The results indicated that all of the compounds showed stronger antiproliferative activities than ?-elemene as well as improved aqueous solubility. In particular dimer 6q showed the strongest cytotoxicity against four tumor cell lines (SGC-7901, HeLa, U87 and A549) with IC50 values ranging from 4.37 to 10.20 ?M. Moreover, combination of 6q with cisplatin exhibited a synergistic effect on these cell lines with IC50 values ranging from 1.21 to 2.94 ?M, and reversed the resistance of A549/DPP cells with an IC50 value of 2.52 ?M. The mechanism study revealed that 6q caused cell cycle arrest at the G2 phase and induced apoptosis of SGC-7901 cells through a mitochondrial-dependent apoptotic pathway. Further in vivo study in H22 liver cancer xenograft mouse model validated the antitumor activity of 6q with a tumor inhibitory ratio (TIR) of 60.3%, which was higher than that of ?-elemene (TIR, 49.1%) at a dose of 60 mg/kg. Altogether, the potent antitumor activity of 6qin vitro and in vivo warranted further preclinical investigation for potential anticancer chemotherapy.

High impedance faults (HIF) are defined as circumstances where the fault current drawn is not sufficient to trip conventional protective devices due to the high impedance path. HIF is a common occurrence in medium voltage distribution networks. The broken live conductors can be a hazard to personal safety. In most cases, high temperature arcing is associated with such faults which can lead to fire. Detection of HIF has been a challenging problem due to its low amplitude and complex dynamics. In this thesis, the recorded data from extensive experiments conducted in the UNSW High Voltage Laboratory and those obtained through HRL Technology Pty Ltd (Victoria) have been studied and summarized. Experiments were also conducted to study the feasibility of using the existing metering current transformers installed on distribution networks for HIF sensing (thus avoid the need for new sensors on the network). The distinctive features of arcing HIF were obtained from the data. An arc model based on the thermal differential equations has been simulated and optimised by using differential evolution method in MATLAB. The simulation results are compared and fitted with experimental arcing data. The standard IEEE test networks are chosen as benchmark for case study and several types of power transients are simulated as well which are used as discrimination signals. Detection algorithms based on the wavelet transform and neural network are proposed based on the integrated simulation system and verified using experimental arcing data. Both results show that the HIF can be accurately detected and reliably discriminated from other faults.

This paper is to show a case study from Junggar Basin in North West China, which integrates a variety of logging data acquired by latest wireline measurements to analyze and evaluate lithology, pore types, fluid types and geomechanics properties of volcanic reservoir. Interpretation of volcanic reservoir has always been a great challenge. Recently, a lot more advanced data sets are available from the new wireline tools and measurements in Xinjiang Oilfield, such as SonicScanner, LithoScanner, Images logs, and latest 3D Saturn Radial probe forvolcanicformation sampling. The new data provide a better view for avolcanic reservoir. An integrated evaluation workflow that combines multiple latest wirelinetechnologies has been set, which can provide a good solution to the evaluation of volcanic reservoir in this area. Calibrating high precision and high-resolution lithology data to core data can accurately describe the complex lithology of volcanic reservoir. Meanwhile, apart from fractures identification, we are not only be able to categorize rock type with help of structure analysis provided by image data, but also can analyze the volcanic eruptible period by comparing images of adjacent wells. In addition, by acquiring, processing and interpreting advanced sonic scanner data; we can evaluate formation anisotropy, fracture effectiveness, identify gas zones and calculate geomechanics parameters, which will be used later during stimulation. In the end, utilizing the 3D Radial probes, the formation tester can confirm the fluid type by the downhole analyzer and actual fluid samples, this greatly reduce the uncertainly for evaluation and later stimulation. In this example, Well A from XinJiang oilfield, JinLong Block, is a typical volcanic formation which is characterized by highly developed natural fractures with various attitudes, complex lithology, which mainly contains andesitic volcanic breccia, breccia andesite, basalt, andesite, tuff and volcanic sedimentary rock, and quite low matrix permeability. Thus, SonicScanner, LithoScanner and FMI data have been acquired, and the favorable lithology, well-developed fracture zones, and high matrix porosity zones have been identified, the "sweet spot" have been located. In the end, the actual gas sample has been obtained for the first time by formation testers using 3D radial probe in volcanic reservoir in CHINA. This case study is a good example of volcanic reservoir evaluation. A workflow that is applicable to this area has been formed, which can be used as guidance for evaluation of other similar wells in the future.

Rice husk is a plentiful agricultural byproduct. In this paper, rice husk (RH) surface was first treated by NaOH/urea into a modified-rice husk(MRH), then the MRH was used as a new template for polymerization of acrylamide(AM) on MRH, as a result, the product named as MRH-g-AM, was formed by the free-radical initiation in aqueous solution using ammonium persulfate as an initiator. The polymer grafted on the MRH was considered as a novel copolymer which was thereafter analyzed by FTIR and SEM. The product was washed thoroughly with distilled water to remove all unreactive chemicals. The results showed that MRH was successfully reacted with AM. The SEM images indicated that MRH-g-AM appeared distinct cracks and formed a loosen structure in comparison with RH, indicating the facilitation of heavy metal ion adsorption in the future wastewater treatment.

Previous studies have shown that cost of illness (COI) measures are lower than the conceptually correct willingness-to-pay (WTP) measure of the economic benefits of disease prevention. We compare COI with stated preference estimates of WTP associated with shigellosis in a rural area of China. COI data were collected through face-to-face interviews at 7 and 14 days after culture-confirmed diagnosis. WTP to avoid an episode similar to the one the respondent just experienced was elicited using a sliding-scale payment card. In contrast to previous studies' findings, average COI estimates (2002 PPP adjusted US dollars 28.2) approximate an upper bound estimate of WTP, rather than a lower bound. One explanation for the similarity between COI and WTP is that preventive expenditures and disutility due to pain and suffering are low for shigellosis. WTP to avoid additional cases in children aged 0-5 years is higher than in adults. Also, average COI (2002 PPP adjusted US dollars 28.4) for children is similar to a lower bound estimate of WTP (2002 PPP adjusted US dollars 16.4) and lies within the WTP range. Because the monetary loss associated with another episode in children is small, caregivers' higher WTP may be attributable to the disutility of illness due to the children's pain and suffering. These findings suggest that for some diseases, COI may approximate more comprehensive measures of economic benefits.

As interest grows in formations with permeability ranging from tight ( The tight gas formations have poor borehole condition for conventional probe sealing and testing. A total of 25 attempts by two different conventional probes fail to seal. However, three stations for the 3D radial probe took less than 4 hours per station to successfully collect PVT-quality samples. Fast cleanup to flow pure formation fluids enabled better accuracy in real-time fluid identification, sampling assurance, and compositional analysis including CO2. Transient analysis indicated that all stations have Performance was compared against conventional modules. The advantages of the 3D radial probe over elliptical probes and dual-packer module in this kind of tight gas reservoirs are obvious and significant, with better efficiency, quality and operability such as applicable differential pressure, sealing capability, minimum storage, no exposure to borehole mud, and less sticking and plugging probabilities. Numerical modeling of an immiscible water-gas system with representative borehole conditions and reservoir properties of tight gas formations was conducted to investigate flow and pressure transient behaviors for operation optimization. Initial results of the simulations will be briefly discussed in this paper.

Considering nonlinear and uncertainty of the system and complex contour error model, in order to improve contour machining precision, a global fast terminal sliding mode control based on equivalent errors method was proposed. Nonlinear equivalent errors model of direct drive XY table by permanent magnet linear synchronous motor(PMLSM), which is easily calculated, was built by using equivalent errors method. Direct drive XY table contour controller was designed by global fast terminal sliding mode method. The method can make the states of the system converge fast to the equilibrium point in finite time and reduce the affect of load disturbance and uncertainty of the system. The simulation results show that the designed contour controller can make the system of direct drive XY table have high contour machining precision and strong robustness.

In this paper, an nickel-chromium (NiCr) alloy piezoresistive atmosphere pressure sensor, based on eutectic bonding is presented. Compared with conventionally silicon piezoresistive pressure sensor, it has the advantages with low cost and easy fabrication processes. First, NiCr alloy (80:20 wt%) is used as the strain detecting material, with a smaller but acceptable sensitivity and simpler processes. Second, eutectic bonding technology based on silver-tin (Ag-Sn) alloy, which is 3.5%wt Ag and 20um thickness, is used as an alternative and easy bonding choice to complete the vacuum package. Bonding quality of eutectic bonding is evaluated by inspection through the deflection of diaphragm of silicon with more than 95% of the area successfully bonded. The Pressure-Voltage characteristic test results suggest a precision within 0.3% in square fitting. The temperature characteristics is also tested and theoretically analyzed. The temperature coefficient offset (TCO) is 620 ppm/(°C FSO).