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- 摘要
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- 实验方案
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Repeatability and Reproducibility of Measures of Bovine Methane Emissions Recorded using a Laser Detector
摘要： Methane (CH4) emissions represent a worldwide problem due to their direct involvement in atmospheric warming and climate change. Ruminants are among the major players in the global scenario of CH4 emissions, and CH4 emissions are a problem for feed e?ciency since enteric CH4 is eructed to the detriment of milk and meat production. The collection of CH4 phenotypes at the population level is still hampered by costly and time-demanding techniques. In the present study, a laser methane detector was used to assess repeatability and reproducibility of CH4 phenotypes, including mean and aggregate of CH4 records, slope of the linear equation modelling the aggregate function, and mean and number of CH4 peak records. Five repeated measurements were performed in a commercial farm on three Simmental heifers, and the same protocol was repeated over a period of three days. Methane emission phenotypes expressed as parts per million per linear meter (ppm × m) were not normally distributed and, thus, they were log-transformed to reach normality. Repeatability and reproducibility were calculated as the relative standard deviation of ?ve measurements within the same day and 15 measurements across three days, respectively. All phenotypes showed higher repeatability and reproducibility for log-transformed data compared with data expressed as ppm × m. The linear equation modelling the aggregate function highlighted a very high coe?cient of determination (≥0.99), which suggests that daily CH4 emissions might be derived using this approach. The number of CH4 peaks resulted as particularly diverse across animals and therefore it is a potential candidate to discriminate between high and low emitting animals. Results of this study suggest that laser methane detector is a promising tool to measure bovine CH4 emissions in ?eld conditions.
关键词： sustainability,e?ciency,environment,methane emission
更新于2025-09-23 15:19:57
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Diffuse-reflection-based single-ended laser absorption sensor for H2O temperature and concentration in kerosene-fuelled combustor
摘要： The design, optimization and demonstration of a compact, single-ended laser absorption sensor based on diffuse-wall-reflected signal is presented for temperature and H2O concentration measurements in a kerosene-fuelled aero-combustor. Challenges of laser measurements in such harsh, practical combustion environments involve strong beam-steering, low signal-to-noise ratio (SNR), and constrained optical access. We here present detailed characterization and optimization procedure of a single-ended optical configuration using a holed off-axis parabolic mirror as the pitch and catch optics, and the coked wall surface of the combustor as a diffuse reflector. A near-infrared distributed-feedback diode laser near 1.4 μm scanned at 1 kHz for direct absorption detection was used to access two H2O transitions for concentration and temperature measurement. Optical system design and adaptive Savitzky-Golay signal processing algorithm was used for noise suppression and SNR amelioration. The sensor was demonstrated under practical conditions in a kerosene-fuelled swirl combustor. High signal fidelity was achieved and allowed for single-scan H2O concentration detection limit of 122 ppm-m-Hz-1/2 despite a low reflected laser intensity level of ~50 μW. In situ, time-resolved measurements detected temperatures ranging from ~1100 K to 1300 K, and H2O concentration ranging from ~8% to 12% as global equivalence ratio varied between 0.2 and 0.45. The results revealed expected trend while demonstrating much faster response and less delay versus a comparing thermocouple. This successful field manifestation provides direct proof for the robustness and reliability of diffuse-reflection-based single-ended sensor system in engine combustion chamber environments.
关键词： single-ended,turbulent environment,combustion diagnostics,laser absorption sensing,kerosene-fuelled combustor
更新于2025-09-23 15:19:57
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Cyclic-controlled quantum operation teleportation in noisy environment
摘要： A scheme is proposed for cyclic-controlled quantum operation teleportation (CCQOT) for three sides with EPR and cluster states. Under the control of David, Alice can implement an unknown single-qubit unitary operation on the remote Bob's quantum system, while Bob can execute a single-qubit unitary operation on Charlie's quantum system and Charlie can also perform an unknown single-qubit unitary operation on Alice's quantum system. Our scheme can be generalized to nen (cid:2) 3) agents involved in the cycle to realize the transmission of single-qubit operations. Moreover, by replacing the quantum channels, we can change the cyclic direction of controlled qunatum operation teleportation (CQOT) from clockwise to counter-clockwise. In addition, we discuss our scheme in four types of noisy environments (amplitude-damping, phase-damping, bit-°ip and phase-°ip noisy environment), and use ˉdelity to analyze the amount of information lost in the process of CCQOT due to noise. The results show that the ˉdelity is determined by decoherence rate and amplitude parameters of the ˉnal state.
关键词： noisy environment,Bell-state measurement,ˉdelity,Cyclic-controlled quantum operation teleportation
更新于2025-09-23 15:19:57
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Data-Enabled Advancement of Computation in Engineering: A Robust Machine Learning Approach to Accelerating Variational Methods in Electromagnetics and Other Disciplines
摘要： One critical issue, for a wireless sensor network (WSN) to operate successfully, is to provide sufficient sensing coverage. Define the smart sensing environment as a sensing system with the capability to sense the environment and respond properly in an automated manner. In this paper, we target on smart sensing environments and deal with heterogeneous sensors (here sensor heterogeneity is defined as sensors having different sensing ranges) equipped with actuation facilities to assist in the sensor self-deployment. A coverage-aware sensor automation (CASA) protocol is proposed to realize an automated smart monitoring network. Two centralized algorithms are included in the CASA protocol suite: enhanced virtual forces algorithm with boundary forces (EVFA-B) and sensor self-organizing algorithm (SSOA). Unlike most previous works that tackle the deployment problem only partially, we intend to address the problem from both global deployment (EVFA-B) and local repairing (SSOA) perspectives. The EVFA-B protocol exerts weighted attractive and repulsive forces on each sensor based on predefined distance thresholds. Resultant forces then guide the sensors to their suitable positions with the objective of enhancing the sensing coverage (after a possibly random placement of sensors). Furthermore, in the presence of sensor energy depletions and/or unexpected failures, our SSOA algorithm is activated to perform local repair by repositioning sensors around the sensing void (uncovered area). This capability of local recovery is advantageous in terms of saving the communication and moving energies. Performance of the proposed sensor deployment strategies is evaluated in terms of surveillance coverage, monitoring density, network self-healing competence, and moving energy consumption. We also implement our CASA protocol suite in a real-life monitoring network (MoNet) to demonstrate the protocol feasibility and validate the MoNet detection capability of emergency events.
关键词： smart sensing environment,sensor automation,self-healing,coverage problem,Wireless sensor deployment
更新于2025-09-23 15:19:57
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[IEEE 2019 2nd International Conference on Electrical, Communication, Computer, Power and Control Engineering (ICECCPCE) - Mosul, Iraq (2019.2.13-2019.2.14)] 2019 2nd International Conference on Electrical, Communication, Computer, Power and Control Engineering (ICECCPCE) - Virtual Environment Modelling using Simulated Laser Scanners
摘要： Life quality of people with sever motor disabilities can be improved by developing and inventing new assistive technologies. In this context, it is proposed to develop a semi-autonomous electric wheelchair that has capabilities of navigating through various environments which include different types and sizes of obstacles. This paper describes a methodology to use a range laser scanner mounted on an electric wheelchair to map different environments. The electric wheelchair is simulated in a virtual environment and is developed at the Neurophysiology Laboratory of University of Strathclyde. Mapping the environment is dependent on the information provided by the range laser. An algorithm was developed in MATLAB to record the data received by the range laser and use the data to map the environments and produce a 2D map. The suggested algorithm has been tested using two virtual environments representing rooms with different features. The results showed that range laser scanner can be used on an electric wheelchair platform for efficient mapping of the environment.
关键词： Assistive technologies,Range laser scanner,Virtual environment,Electric wheelchair,Shared control
更新于2025-09-23 15:19:57
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nAdaptive detection of point-like targets based on a reduced-dimensional data model
摘要： This paper approaches the problem of detecting a point-like target in Gaussian background. The useful signal lies in an one-dimensional subspace spanned by a known steering vector. The Gaussian disturbance fills the whole observation space. Since the disturbance outside the signal subspace is unrelated to the decision result, it is eliminated by pre-multiplying the recorded data by the conjugate transpose of the steering vector in this paper. This preprocessing is not applied in the classical detectors, such as the generalized likelihood ratio test (GLRT), the adaptive matched filter (AMF), etc. This preprocessing results in a new scalar data model where the useful signal and disturbance lie in the same space. Based on this scalar data model, two new detectors are designed through the one-step and two-step GLRT, respectively. Their probabilities of false alarms and detections are derived analytically. The one- (two-) step GLRT-based detector has the (approximately) constant false alarm rate feature in the Gaussian background. Simulation results show that the proposed detectors outperform those classical ones when finite training data is available. The one-step GLRT-based detector is more robust to mismatched signals than those classical detectors.
关键词： generalized likelihood ratio test,Adaptive detection,constant false alarm ratio,homogeneous environment,point-like target
更新于2025-09-23 15:19:57
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Ethanol-Precipitable Silica-Passivated Perovskite Nanocrystals Incorporated into Polystyrene Microspheres for Long-Term Storage and Re-Usage
摘要： Perovskite nanocrystals (PNCs) are emerging luminescent materials due to their fascinating physic-optical properties. However, their sensitive surface chemistry with organic polar solvents, oxygen and moisture greatly hinders their developments towards practical applications. Herein we promote silica-passivated PNCs (SP-PNCs) by in situ hydrolyzing the surface ligands of (3-aminopropyl) triethoxysilane. The resultant SP-PNCs possesses a high quantum yield (QY) of 80% and are precipitable by polar solvents, such as ethanol and acetone, without destroying their surface chemistry or losing QY, which offers an eco-friendly and efficient method for separation, purification and phase transfer of PNCs compared with the traditional solvent evaporation technique. Moreover, we further promoted a swelling-deswelling encapsulation process to incorporate the as-made SP-PNCs into polystyrene microspheres (PMs), which can largely increase the stability of the SP-PNCs against moisture for long-term storage. Besides, the embedded SP-PNCs can also be reused and mono-dispersed by totally dissolving the PMs in suitable solvents for making all-solution-processed devices. We thereby believe this work should open new avenues for greener synthesis, scalable production, and long-term storage of PNCs towards the emerging practical applications.
关键词： surface engineering,polar environment,perovskite nanocrystals,encapsulation,stability
更新于2025-09-19 17:15:36
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Multidimensional analysis of groundwater pumping for irrigation purposes: Economic, energy and environmental characterization for PV power plant integration
摘要： Nowadays, the agriculture sector presents relevant opportunities to integrate renewable energy sources as an alternative solution to mitigate fossil-fuel dependence and decrease emissions. Moreover, this sector demands a detailed review of energy uses and other factors that are addressed as priority issues in most developed countries. In this framework, groundwater pumping energy requirements for agriculture irrigation emerge as a relevant topic to be improved in terms of power demand. Actually, this demand is currently supplied by diesel equipment solutions, with relevant drawbacks such as: (i) a large energy dependence on fossil fuels for the agricultural sector and (ii) a lack of participation in reducing CO2 emissions. This paper proposes a multidimensional characterization to evaluate photovoltaic (PV) solar energy integration into groundwater pumping requirements. Alternative solutions are compared under economic, energy and environmental aspects; thus providing an extensive scenario where the considerable influence of multiple factors such as water needs, irrigation area or aquifer depth are explicitly considered. Extensive results based on a real Spanish aquifer and discussion about the solutions are also included in the paper.
关键词： PV systems,Characterization of energy alternatives,Solar pumping,Optimization energy requirement,Economic-Energy-Environment (3E) Analysis.,Agricultural development
更新于2025-09-19 17:15:36
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A Turn-On Fluorescent Probe for Sensitive Detection of Cysteine in a Fully Aqueous Environment and in Living Cells
摘要： We reported here a turn-on fluorescent probe (1) for the detection of cysteine (Cys) by incorporating the recognition unit of 2,4-dinitrobenzenesulfonyl ester (DNBS) to a coumarin derivative. The structure of the obtained probe was confirmed by NMR and HRMS techniques. The probe shows a remarkable fluorescence off-on response (～52-fold) by the reaction with Cys in 100% aqueous buffer. The sensing mechanism was verified by the HPLC test. Probe 1 also displays high selectivity towards Cys. The detection limit was calculated to be 23 nM. Moreover, cellular experiments demonstrated that the probe is highly biocompatible and can be used for monitoring intracellular Cys.
关键词： living cells,aqueous environment,fluorescent probe,turn-on,cysteine
更新于2025-09-19 17:15:36
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[IEEE 2018 International Conference on Sensor Networks and Signal Processing (SNSP) - Xi'an, China (2018.10.28-2018.10.31)] 2018 International Conference on Sensor Networks and Signal Processing (SNSP) - Research on the IR-UWB Ranging Algorithm in Outdoor Near-Ground Environment
摘要： Impulse radio ultra-wideband (IR-UWB) has been adopted in wireless sensor networks (WSN) research due to its high precision ranging and localization capability. Focus on the outdoor near-ground environment, the propagation characteristics of IR-UWB signal is experimentally researched. A time-of arrival (TOA) ranging algorithm is proposed. Based on the matched filter (MF) receiver, the searching steps of the direct path (DP) component in the dense multipath are discussed. The Kalman filter is also used to improve the performance of the ranging estimation. Experimental results show that the proposed algorithm is able to acquire accurate ranging results and well-suited for the WSN application in outdoor near-ground environment.
关键词： outdoor near-ground environment,IR-UWB,ranging algorithm
更新于2025-09-19 17:15:36