- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 Conference on Electrotechnology: Processes, Models, Control and Computer Science (EPMCCS) - Kielce, Poland (2018.11.12-2018.11.14)] 2018 Conference on Electrotechnology: Processes, Models, Control and Computer Science (EPMCCS) - Investigation and Determination of Efficiency of the Waste Heat Recovery System Using Peltier Modules
摘要： High efficiency technology of waste heat energy utilization would change the face of the energy market. Due to the fact that the energy system and transport are based on fossil fuels, there is a huge potential for its efficient use. Despite the fact that the technology of Peltier semiconductor modules has been known for many years, there are no solutions that might be commonly disseminated. There is also a deficit of available sources that in a transparent, coherent and synthetic way could provide guidelines for the constructors of such devices, and show how much energy they can generate and what efficiency they have. Moreover, the Peltier modules available on the market are burdened with many stereotypes. When trying to use this technology, it should be remembered that in addition to the Peltier phenomenon, the module's operation is based on four other physical phenomena: two of them have a negative impact and they determine the practically obtained parameters of the Peltier module. These are: Joule effect and heat conduction phenomenon. The other two phenomena: Seebeck and Thomson ones, play slightly smaller roles. The aim of the authors was to investigate the self-made model of a thermoelectric generator TEG, constructed using Peltier modules. The paper presents the results of measurements and the method of determining the electrical efficiency of this model. Additionally, a temperature range was determined at that such recovery has a measurable utilitarian aspect and economic sense. The limitations of semiconductor technology of Peltier cells have been given, and design guidelines at construction process of such systems to optimize their efficiency are presented.
关键词： Seebeck effect,thermoelectric generator TEG,determination of efficiency,Peltier module
更新于2025-09-23 15:23:52
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[IEEE 2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Chengdu, China (2018.5.7-2018.5.11)] 2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - A High Efficiency TE<inf>01</inf>- TE<inf>11</inf> Mode Converter
摘要： A high efficiency TE01-TE11 mode converter is designed and analyzed based on coupled wave theory. The optimal configurations of a three-period converter is obtained to realize the optimal conversion at 30.5 GHz. The simulation results show that a conversion efficiency of up to 99.85% is got with a bandwidth of 4.4% over a converting efficiency of 95%, and the TE11 mode purity is also up to 99.9% at the output port.
关键词： high mode purity,TE01-TE11,mode converter,high conversion efficiency
更新于2025-09-23 15:23:52
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Research on the influence of alignment error on coupling efficiency and beam quality for Gaussian beam to multimode fiber
摘要： The effect of alignment error on the coupling efficiency and beam quality of a Gaussian beam coupled into a large-core multimode fiber is studied in this paper. The equations for evaluating the effect of alignment error on the coupling efficiency are derived separately, and verified with the method of simulation. The calculation and simulation results obtained are highly consistent. In the same way, the effects of alignment error on the beam power distribution are discussed. The results show that the lateral error will change the path of partial light to a large extent, and have a greater influence on the power distribution of the Gaussian beam than the longitudinal error and angular error do.
关键词： Multimode fiber,Coupling efficiency,Beam quality,Alignment error
更新于2025-09-23 15:23:52
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Bumpy Hollow Gold Nanospheres for Theranostic Application: Effect of Surface Morphology on Photothermal Conversion Efficiency
摘要： The combination of hollow core and rugose surface morphology is highly attractive for photoactive near-infrared (NIR) nanomaterials. Here, we present a facile pH modification to hollow gold nanosphere (HGN) synthesis to enable controlled tuning of the surface morphology from smooth to very bumpy. Unlike other methods, the synthetic protocol does not require harsh surfactants, secondary reducing agents, or organic solvents. The resultant bumpy HGNs (bHGNs) are highly monodisperse with little variation in protrusion length from particle to particle. Mechanistic studies suggest that surface rugosity is mainly controlled by the presence of free OH- ions in solution. We also present the first systematic investigation into the effect of surface morphology on the photothermal conversion efficiency (PCE) of bumpy as well as smooth HGNs, with a maximum PCE reaching 99%. Although expected to have a higher scattering component, the bHGNs retain the excellent PCE of their smooth counterparts, which may be due to efficient reabsorption of scattered light.
关键词： surface plasmon resonance,photothermal conversion efficiency,heat generation,surface morphology,hollow gold nanospheres
更新于2025-09-23 15:23:52
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IoT Based Framework: Mathematical Modelling and Analysis of Dust Impact on Solar Panels
摘要： The solar photovoltaic performance is governed by manifold parameters viz. temperature, irradiance, dust on solar module, photoactive material, panel orientation. Among these dust is a critical impediment, as its accumulation on panel surface degrades its productivity; while frequent cleaning sessions affect module's life and result into PV destruction. Accordingly, the need to know dust thickness responsible for deteriorating panel's capability and adequate cleaning time of solar panels to produce optimum yields is requisite. This paper aims to discern a right cleaning time, owing to a particular dust thickness so as to conserve the panel efficiency using internet of things (IoT). The mathematical correlations of PV efficiency and current with thickness of accumulated dust are derived using linear regression. Further, these equations are associated with an IoT-based platform which remotely monitors and records PV output current; thereafter dust thickness corresponding to a significant current reduction is estimated. For this, experimental data of 46 inverters with total 114,819.30 kWh productions in a month with an average of 4416.13 kWh/day is accessed and the results pertaining to mathematical analysis exhibit a decline in current by 1 A with 5.51 × 10^{-3} mm thickness of dust.
关键词： Transmittance,Photovoltaic module,Output efficiency,Dust deposition
更新于2025-09-23 15:23:52
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One-out-of-two Quantum Oblivious Transfer based on Nonorthogonal States
摘要： This research proposes the first one-out-of-two quantum oblivious transfer (QOT) scheme that does not have a two-level structure and is not subject to Lo’s no-go theorem. Instead, the proposed scheme is a simple and efficient approach based on nonorthogonal states. The nonorthogonality causes one of a pair of messages to be unable to be measured to achieve the irreversible goal of discarding a message, resulting in a one-out-of-two selection effect. The proposed QOT protocol is therefore built directly on quantum resources rather than on a two-level structure in which two classical keys must first be created using quantum resources (all-or-nothing QOT) and then a one-out-of-two protocol is built from there. Furthermore, the proposed protocol allows Alice and Bob to test each other’s loyalty by comparing measurement results. In addition, the relationship with the no-go theorem is discussed in detail; this relationship is often overlooked in other studies. A security analysis demonstrates that the proposed protocol is secure against both external and internal attacks. In addition, an efficiency analysis shows that the proposed protocol is more efficient than other, two-level-structured protocols.
关键词： quantum oblivious transfer,security analysis,efficiency analysis,nonorthogonal states,Lo’s no-go theorem
更新于2025-09-23 15:23:52
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Design and Implementation of Digital Phase Locked Loop for Single-Phase Grid-Tied PV Inverters
摘要： The rational design of porphyrin sensitizers is always crucial for dye-sensitized solar cells (DSSCs), since the change of only a single atom can have a significant influence on the photovoltaic performance. We incorporated the pyridothiadiazole group, as a stronger electron-withdrawing group, into the commonly well-established skeleton of D-porphyrin-triple bond-acceptor sensitizers by a single atom change for a well-known strong electron-withdrawing benzothiadiazole (BTD) unit as an auxiliary acceptor. The impact of the pyridothiadiazole group on the optical; electrochemical; and photovoltaic properties of D–π–A porphyrin sensitizers was investigated with comparison for a benzothiadiazole-substituted SGT-020 porphyrin. The pyridothiadiazole-substituted SGT-024 porphyrin dye was red-shifted so that the absorption range might be expected to achieve higher light harvest efficiency (LHE) than the SGT-020 porphyrin. However, all the devices were fabricated by utilizing SGT-020 and SGT-024, evaluated and found to achieve a cell efficiency of 10.3% for SGT-020-based DSSC but 4.2% for SGT-024-based DSSC under standard global AM 1.5G solar light conditions. The main reason is the lower charge collection efficiency of SGT-024-based DSSC than SGT-020-based DSSC, which can be attributed to the tilted dye adsorption mode on the TiO2 photoanode. This may allow for faster charge recombination, which eventually leads to lower Jsc, Voc and power conversion efficiency (PCE).
关键词： D–π–A structural porphyrin,charge collection efficiency,acceptor units,charge recombination,dye-sensitized solar cells
更新于2025-09-23 15:23:52
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Effect of the Orientation Schemes of the Energy Collection Element on the Optical Performance of a Parabolic Trough Concentrating Collector
摘要： While the circular shape is currently the proven optimum design of the energy collection element (ECE) of a parabolic trough collector, that is yet to be confirmed for parabolic trough concentrating collectors (PTCCs) like trough concentrating photovoltaic collectors and hybrid photovoltaic/thermal collectors. Orientation scheme of the ECE is expected to have significant effect on the optical performance including the irradiance distribution around the ECE and the optical efficiency, and therefore, on the overall energy performance of the PTCC. However, little progress addressing this issue has been reported in the literature. In this study, a thorough investigation has been conducted to determine the effect of the orientation schemes of ECE on the optical performance of a PTCC applying a state-of-the-art Monte Carlo ray tracing (MCRT) technique. The orientation schemes considered are a flat rectangular target and a hollow circular, semi-circular, triangular, inverted triangular, rectangular and rectangle on semi-circle (RSc). The effect of ECE defocus, Sun tracking error and trough rim angle on the optical performance is also investigated. The MCRT study reveals that the ECE orientation schemes with a curved surface at the trough end showed much higher optical efficiency than those with a linear surface under ideal conditions. ECEs among the linear surface group, the inverted triangular orientation exhibited the highest optical efficiency, whereas the flat and triangular ones exhibited the lowest optical efficiency, and the rectangular one was in between them. In the event of defocus and tracking errors, a significant portion of the concentrated light was observed to be intercepted by the surfaces of the rectangular and RSc ECEs that are perpendicular to the trough aperture. This is an extended version of a published work by the current authors, which will help to design an optically efficient ECE for a parabolic trough concentrating collector.
关键词： optical efficiency,optical performance,concentrating solar power,parabolic trough concentrating collector,irradiance distribution,Monte Carlo ray tracing
更新于2025-09-23 15:23:52
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Practical performance of a small PTC solar heating system in winter
摘要： The active solar house-heating in winter is a novel technology that is eco-friendly and economical. The performance of a small solar heating system composed of parabolic trough collector (PTC) and ventilation pipelines has been experimentally investigated in the current study. With an automatic solar-tracking device, the system adopted a PTC device of aperture area 2.407 m2. The air stream was heated in the tube collector and then driven into the test room. By examining the heat gain of the air stream passing through the PTC as well as the temperature distribution of the indoor air, the working characteristic of the solar-heating system in winter was evaluated practically. The experimental results showed that for the generally-insulated room that was located in 39.87°N latitude, the daily solar heating time reached to 6–7 h, and the thermal efficiency of the PTC device was above 60%. Supposing the heat loss is reduced effectively along the outdoor pipelines in the future, such active solar heating system will be a promising heating technology in regions that are not far north on the earth.
关键词： Thermal efficiency,Solar energy,PTC,House heating
更新于2025-09-23 15:23:52
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Evaluation of Signal Regeneration Impact on the Power Efficiency of Long-Haul DWDM Systems
摘要： Due to potential economic benefits and expected environmental impact, the power consumption issue in wired networks has become a major challenge. Furthermore, continuously increasing global Internet traffic demands high spectral efficiency values. As a result, the relationship between spectral efficiency and energy consumption of telecommunication networks has become a popular topic of academic research over the past years, where a critical parameter is power efficiency. The present research contains calculation results that can be used by optical network designers and operators as guidance for developing more power efficient communication networks if the planned system falls within the scope of this paper. The research results are presented as average aggregated traffic curves that provide more flexible data for the systems with different spectrum availability. Further investigations could be needed in order to evaluate the parameters under consideration taking into account particular spectral parameters, e.g., the entire C-band.
关键词： DWDM,phase shift keying,differential phase shift keying,power consumption,spectral efficiency,sub-band spacing,WDM networks,single-line rate,optical fibre networks,power efficiency,energy efficiency
更新于2025-09-23 15:22:29