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781.
This paper presents a new design of a prototype refrigeration-cum-hot water heating system for domestic use. The system uses the heat energy rejected from the compressor and condenser of a vapour-compression refrigerator by storing it in a heat sink. This energy is then transferred to mains water entering the hot water cylinder, where the water temperature is boosted by an electric resistance heater to a preset temperature for domestic usage. A prototype system of such a configuration was assembled as an integrated unit with the refrigerator adjacent to the water tank. The system is called the Home Energy Centre (HEC). Power consumption and temperature distribution were measured for standing and draw off tests using the unit as a conventional hot water cylinder, refrigerator or as the combined system. A new parameter, ϕ, is defined to compare the system performance as the HEC prototype against its performance when working only as a refrigerator or a water heater. The system performed better as the prototype than it did as a hot water heater, but needs to be improved further to fully explore its expected potential. © 1998 John Wiley & Sons, Ltd. 相似文献
782.
International Journal of Information Security - Fake news has become an industry on its own, where users paid to write fake news and create clickbait content to allure the audience. Apparently, the... 相似文献
783.
Performance analysis of two‐hop decode‐amplify‐forward relayed system in different fading conditions
Recent advances in the field of wireless communication have proven the importance of diversity in combating channel fading and improving the bit error rates (BERs). In this report, a dual‐hop decode‐amplify‐forward (DAF) transmission system over Nakagami‐m fading channel is studied. The DAF relay system is a hybrid of decode‐and‐forward and amplify‐and‐forward relay systems that shows the benefits of both decode‐and‐forward and amplify‐and‐forward relay systems and is also called hybrid relay system or hybrid DAF relay system. Signal‐to‐noise ratios and BERs for various system models with varying number of transmit and receive antennas have been discussed. The diversity is achieved in two ways: firstly, by the use of relay and secondly, by the use of multiple antennas at both the transmitter and the receiver. Dual‐hop relaying gives better trunking efficiency and with single antenna at the relay site acquisition and antenna structures are much less expensive. The variations in the performance levels when the relay is moved to different locations within the line of sight of the transmitter and the receiver have also been analyzed. BERs with respect to variations in the fading parameter ‘m’ have also been presented and discussed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
784.
Jain Vipin Ramos‑Meza Carlos Samuel Aslam Ejaz Chawla Chanchal Nawab Tabish Shabbir Malik Shahzad Bansal Ajay 《Clean Technologies and Environmental Policy》2023,25(3):779-779
Clean Technologies and Environmental Policy - 相似文献
785.
Sidharth Kumar Sethi Rupesh Raina Shyam Bihari Bansal Anvitha Soundararajan Maninder Dhaliwal Veena Raghunathan Meenal Kalra Kritika Soni Samit Kumar Mahato Ananya Vadhera Dinesh Kumar Yadav Timothy Bunchman 《Hemodialysis international. International Symposium on Home Hemodialysis》2023,27(3):308-317
786.
Sudesh Kumar Ram Shringar Raw Abhishek Bansal 《International Journal of Communication Systems》2023,36(2):e5375
Recently, flying ad hoc networks (FANETs) has become a core research area in wireless networks that involves multiple unmanned aerial vehicles (UAVs). It is widely used in modern warfare for surveillance, monitoring and reconnaissance. The routing in FANETs poses a more significant challenge due to limited energy and frequent link disconnection between the UAVs. Consequently, an effective route is always required to ensure data transmission between UAVs. Therefore, this research proposes a link-optimized cone-assisted location (LoCaL) routing protocol for FANETs. The main goal of the proposed LoCaL is to enhance the link duration between the UAVs in which a source selects a forwarding UAV from a given set of neighbours by estimating the residual energy, link duration time and safety degree parameters. Proposed LoCaL provides better stability and less frequent route breaks between source and destination. Further, the mathematical formulation of the proposed approach is presented through the utility function to enhance the route stability by selecting all those relay UAVs in the cone-shaped request zone, which reduces the routing overhead in discovering the route. Finally, the performance of the LoCaL has been presented through key indicators such as energy consumption, routing overhead, message delivery ratio, network lifetime and delay compared to the existing approaches. 相似文献
787.
M. Sharma V. Bansal S. S. Ray R. Sarin D. K. Tuli A. K. Bhatnagar 《Lubrication Science》2003,15(4):321-328
Phosphorodithioate derivatives having different alkyl substitu‐ents have been synthesised, while keeping the core phosphorus‐sulphur moiety intact. The change in antiwear, extreme‐pressure, and antioxidant properties with the variation in sub‐stituents at oxygen and at sulphur linkages in the phosphorodithioates has been studied. The role of the heteroatoms with regard to the alkyl substituents has been examined. The experimental data show that the chemical structure of an additive influences its physicochemical and tribological properties. 相似文献
788.
Akshaya Kumar Swain Arpan Kumar Nayak Sungwook Mhin HyukSu Han 《International Journal of Applied Ceramic Technology》2022,19(2):639-643
Room-temperature ferromagnetic organic magnet is developed via a facile halide exchange process using fluoro-graphite (FG) as a starting material. Structural and chemical analysis reveals that heterogeneous C–F bond cleavage in the defect sites of FG is essentially related to the formation of ferromagnetic hydroxyl-graphene (HG). Pyrolysis of FG in a polar solvent with iodine ions induces a formation of metastable C–I bond and subsequent replacement of the I sites with the hydroxyl groups. Specifically, defective sites can be formed in FG due to nucleophile attack where the OH groups can be easily generated. As a result, the FG can be transformed into the HG with a network of sp2-conjugated carbon motifs in a sp3-based graphene matrix. Hence, the paramagnetic centers in the π-electron system of FG can be transformed to the long-range ordered ferromagnetic centers in the sp2-conjugated system of HG. Electron paramagnetic resonance data demonstrate the weak ferromagnetic property of HG stable at room temperature. 相似文献
789.
Abhinandan Patra Bhavya M. B. G. Manasa Akshaya K. Samal Chandra Sekhar Rout 《Advanced functional materials》2023,33(42):2306680
Surface-enhanced enhanced Raman spectroscopy (SERS) has emerged as a powerful analytical technique for ultrasensitive and label-free detection of chemical species, with numerous applications in various fields. Recently, 2D MXenes, have evoked substantial intrigue as promising substrates for SERS. Hence, a comprehensive understanding of the developments in the Raman effect and the mechanisms involved in SERS is highly crucial. The review reflects the advances, working principle, and dual mechanisms, including SERS's electromagnetic and chemical mechanisms. Noble metal nanostructures are highly prioritized as SERS substrates owing to their excellent sensitivity. However, due to certain disadvantages that they pose, metal-free SERS substrates with exceptional tunable properties are extensively researched in the current days. The combination of 2D MXenes and nanostructures can be effective in producing enhanced SERS signals. SERS performance of different MXene-based materials is emphasized. The performance of this combination is credited to their large surface-to-volume ratio, good electrical conductivity, and surface-terminated functionalities. The recent advancements in MXenes and MXenes-based heterostructures driven SERS sensing concerning the structural design of the material, its performance, and the mechanisms are studied. Finally, a detailed conclusion is provided with the challenges and future perspectives for designing 2D materials for efficient SERS sensors. 相似文献
790.
Jain Vipin Ramos-Meza Carlos Samuel Aslam Ejaz Chawla Chanchal Nawab Tabish Shabbir Malik Shahzad Bansal Ajay 《Clean Technologies and Environmental Policy》2023,25(3):771-777
Clean Technologies and Environmental Policy - This study examines the association between renewable energy strategies and carbon emissions on sustainable economic growth under affordable and clean... 相似文献