The Experts below are selected from a list of 109347 Experts worldwide ranked by ideXlab platform
Giovanni Cortella - One of the best experts on this subject based on the ideXlab platform.
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Energy Benefit assessment of a water loop heat pump system integrated with a co2 commercial refrigeration unit
Energy Procedia, 2017Co-Authors: Alessio Polzot, Chiara Dipasquale, Paola Dagaro, Giovanni CortellaAbstract:Abstract The improvement of Energy efficiency and the use of environmentally friendly working fluids are key elements of current European policies. Supermarkets are intensive Energy consumers and approximately the 40% of their annual Energy consumption is for refrigeration. Direct emissions of greenhouse gases associated with the use of high Global Warming Potential (GWP) refrigerants, and the indirect impact on the environment related to high electrical Energy consumption, make shopping malls not sustainable buildings. This paper analyses the Energy saving potential of integrated supermarket air conditioning and refrigeration systems using a Water Loop Heat Pump system (WLHP). A basic CO2 booster commercial refrigeration system, applied to cold rooms and display cabinets, is considered. Heat recovery from the refrigeration circuit is performed in the heating season, while in the cooling season a dry cooler on the water loop allows heat rejection to outdoors. The building and all systems are modelled in the Trnsys environment taking into account the hourly weather data, the simulated daily profiles of the cooling and heating load demand and the request from refrigerated food storage equipment. Such a model allows a thorough understanding of the potential for Energy savings with heat recovery solutions.
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Energy Benefit assessment of a water loop heat pump system integrated with a CO2 commercial refrigeration unit
Energy Procedia, 2017Co-Authors: Alessio Polzot, Paola D'agaro, Chiara Dipasquale, Giovanni CortellaAbstract:The improvement of Energy efficiency and the use of environmentally friendly working fluids are key elements of current European policies. Supermarkets are intensive Energy consumers and approximately the 40% of their annual Energy consumption is for refrigeration. Direct emissions of greenhouse gases associated with the use of high Global Warming Potential (GWP) refrigerants, and the indirect impact on the environment related to high electrical Energy consumption, make shopping malls not sustainable buildings.\ud This paper analyses the Energy saving potential of integrated supermarket air conditioning and refrigeration systems using a Water Loop Heat Pump system (WLHP), where a water loop is used as a heat source/sink for a number of electric reversible heat pumps which provide climate control on the thermal zones. A basic CO2 booster commercial refrigeration system, applied to cold rooms and display cabinets, is considered. Heat recovery from the refrigeration circuit is performed in the heating season, while in the cooling season a dry cooler on the water loop allows heat rejection to outdoors.\ud A comprehensive model of a commercial building, HVAC and refrigeration integrated systems is presented. The building and all systems are modelled in the Trnsys environment taking into account the hourly weather data, the simulated daily profiles of the cooling and heating load demand and the request from refrigerated food storage equipment. Such a model allows a thorough understanding of the potential for Energy savings with heat recovery solutions. This work is developed in the framework of CommONEnergy, an EU project funded by the European Community within the Seventh Framework Programme (FP7/2007-2013) that aims at reducing Energy consumption in shopping malls
Jos H. Weber - One of the best experts on this subject based on the ideXlab platform.
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ISIT - On the Energy Benefit of compute-and-forward for multiple unicasts
2016 IEEE International Symposium on Information Theory (ISIT), 2016Co-Authors: Jasper Goseling, Jos H. Weber, Michael GastparAbstract:Compute-and-forward (CF) is a technique which exploits broadcast and superposition in wireless networks. In this paper, the CF Energy Benefit is studied for networks with unicast sessions and modeled by connected graphs. This Benefit is defined as the ratio of the minimum Energy consumption by traditional routing techniques, not using broadcast and superposition features, and the corresponding CF consumption. It is shown to be upper bounded by min(d, K, 12√K), where d and K are the average hop-count distance and the number of sessions, respectively. Also, it can be concluded that the Energy Benefit of network coding (NC) is also upper bounded by the same value, which is a new scaling law of the Energy Benefit for NC as a function of K.
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On the Energy Benefit of compute-and-forward on the hexagonal lattice
2014Co-Authors: Zhijie Ren, Jos H. Weber, Jasper Goseling, Michael GastparAbstract:We study the Energy Benefit of applying compute-and-forward on a wireless hexagonal lattice network with multiple unicast sessions with a specific session placement. Two compute-and-forward based transmission schemes are proposed, which allow the relays to exploit both the broadcast and superposition nature of the wireless network. The Energy consumption of both transmission and reception of the nodes are taken into account. We show that with our schemes, the total Energy consumption of the network is significantly reduced compared to traditional routing based transmission schemes. Moreover, our schemes also outperform the plain network coding based transmission scheme in terms of power saving as long as the receive Energy of the devices is not negligible.
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Lower Bounds on the Maximum Energy Benefit of Network Coding for Wireless Multiple Unicast
EURASIP Journal on Wireless Communications and Networking, 2010Co-Authors: Jasper Goseling, Ryutaroh Matsumoto, Tomohiko Uyematsu, Jos H. WeberAbstract:We consider the Energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the Benefit of network coding, defined as the maximum of the ratio of the minimum Energy required by routing and network coding solutions, where the maximum is over all configurations. It is shown that if coding and routing solutions are using the same transmission range, the Benefit in d -dimensional networks is at least . Moreover, it is shown that if the transmission range can be optimized for routing and coding individually, the Benefit in 2-dimensional networks is at least 3. Our results imply that codes following a decode-and-recombine strategy are not always optimal regarding Energy efficiency.
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ISIT - On the Energy Benefit of network coding for wireless multiple unicast
2009 IEEE International Symposium on Information Theory, 2009Co-Authors: Jasper Goseling, Ryutaroh Matsumoto, Tomohiko Uyematsu, Jos H. WeberAbstract:We consider Energy savings offered by network coding for multiple unicast in wireless networks. For d-dimensional wireless networks we show that the maximum possible Benefit is at least 2d/⌊√d⌋
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Energy Benefit of Network Coding for Multiple Unicast in Wireless Networks
arXiv: Information Theory, 2008Co-Authors: Jasper Goseling, Jos H. WeberAbstract:We show that the maximum possible Energy Benefit of network coding for multiple unicast on wireless networks is at least 3. This improves the previously known lower bound of 2.4 from [1].
Jaeweon Jeong - One of the best experts on this subject based on the ideXlab platform.
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Energy Benefit of Liquid Desiccant-Assisted Humidification in Buildings during Winter Operation
Energies, 2021Co-Authors: Soo-jin Lee, Hansol Lim, Jaeweon JeongAbstract:The objective of this study was to modify an existing liquid desiccant and indirect/direct evaporative cooling-assisted 100% outdoor air system (LD-IDECOAS) for humidification operation in winter. The Energy Benefit of the liquid desiccant-assisted humidification approach during the operation of LD-IDECOAS over the conventional method with a steam humidifier was evaluated through a detailed Energy simulation. The humidification and enthalpy effectiveness values of the liquid desiccant humidification measured from laboratory tests were 0.41 and 0.49, respectively, which were applied to the Energy simulation for the modified system. Both systems with the proposed and conventional humidification approaches were simulated using an engineering equation solver combined with a TRNSYS 18 Energy simulation program. The results demonstrated that the modified LD-IDECOAS consumes less Energy for humidification compared to the existing system with a steam humidifier. The proposed system also exhibited considerable heating Energy-saving potential. Consequently, modified LD-IDECOAS consumed 42% less primary Energy during winter operation after being modified for liquid desiccant-assisted humidification.
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Energy Benefit of organic Rankine cycle in high-rise apartment building served by centralized liquid desiccant and evaporative cooling-assisted ventilation system
Sustainable Cities and Society, 2020Co-Authors: Hye-won Dong, Beom-jun Kim, Soo Yeol Yoon, Jaeweon JeongAbstract:Abstract Building heating, ventilating, and air-conditioning systems have high impacts on the Energy and environmental performance of residential buildings. To reduce the Energy consumption of the building for sustainable buildings and cities, this research proposed the organic Rankine cycle (ORC) applied to a centralized liquid desiccant (LD) and evaporative cooling-assisted ventilation system serving an apartment building and evaluated the Energy impact of the proposed system via detailed Energy simulations. As a small combined heat and power application in residential buildings, the ORC produces heat and power that are consumed by the proposed system and the building. A conventional decentralized Energy recovery ventilator powered by the existing power grid was selected as a reference system. The combination of the ORC, LD, and evaporative cooling-assisted ventilation system allows decoupling of the sensible and latent cooling and offers Energy Benefits by reclaiming heat from the ORC compared with the reference system owing to the parallel system of Energy consumption. Energy simulations were conducted for one floor of a 30-story apartment building. The proposed system exhibited 28% annual primary Energy savings and provided a 54% higher annual average coefficient of performance compared with the reference system, although the proposed system consumed more fan and pump Energy. The majority of the operating Energy savings of the proposed system were achieved by reclaiming the waste heat from the ORC condenser.
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Energy Benefit of a cascade liquid desiccant dehumidification in a desiccant and evaporative cooling-assisted building air-conditioning system
Applied Thermal Engineering, 2019Co-Authors: Joonyoung Park, Hye-won Dong, Jaeweon JeongAbstract:Abstract The main objective of this study was to estimate the impact of dehumidification with a cascade liquid desiccant on the primary Energy consumption in a liquid desiccant and evaporative cooling-assisted 100% outdoor air system. Detailed Energy simulations were performed for two systems serving an identical office space: the conventional liquid desiccant and indirect/direct evaporative cooling-assisted 100% outdoor air system (LD-IDECOAS) (i.e., Case 1) having a single-stage liquid desiccant dehumidification section, and a retrofit case of the LD-IDECOAS having a cascade liquid desiccant section (i.e., Case 2) consisting of a two-stage liquid desiccant dehumidifier. The results showed that Case 2 consumed 12% less primary Energy under the peak load condition and 17.4% less primary Energy during the cooling season. The overall thermal and primary coefficients of performance of Case 2 were 0.78 and 2.05, respectively, whereas those of Case 1 were 0.65 and 1.45, respectively. In addition, it was also observed that Case 2 could provide lower supply air temperature to the conditioned space compared with Case 1 owing to enhanced evaporative cooling performance, which was mainly caused by enhanced dehumidification in the cascade liquid desiccant section. The lower supply air temperature resulted in reductions in fan and pump Energy consumptions during the operation.
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Energy Benefit of a dedicated outdoor air system over a desiccant enhanced evaporative air conditioner
Applied Thermal Engineering, 2016Co-Authors: Huijeong Kim, Sungjoon Lee, Sanghyeon Cho, Jaeweon JeongAbstract:Abstract The purpose of this study is to comparatively evaluate the Energy performances of a dedicated outdoor air system (DOAS) and desiccant-enhanced evaporative air conditioner (DEVap) in building applications. The DOAS effectively accommodates latent cooling loads and some of the sensible cooling loads of the space by introducing cooled and dehumidified ventilation air into a building while integrating a parallel system aimed at reducing the remaining sensible load. The DEVap enhances the Energy performance of a variable air volume system by reducing cooling coil loads through preconditioning of the supply air before it reaches a coil. The preconditioning is accomplished by using a liquid desiccant system and dew-point indirect evaporative cooler. In this paper, the operating and annual primary Energy consumptions of both the DOAS and DEVap systems are compared based on detailed Energy simulations. The results indicated the Energy saving potential of DOAS to be greater than that of the DEVap. Specifically, a DOAS with ceiling radiant cooling panels experienced 20% less primary Energy consumption compared to a DEVap.
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annual operating Energy savings of liquid desiccant and evaporative cooling assisted 100 outdoor air system
Energy and Buildings, 2014Co-Authors: Joonyoung Park, Minki Sung, Anseop Choi, Jaeweon JeongAbstract:a b s t r a c t The purpose of this research is to investigate the annual operating Energy performance of a desiccant and evaporative-cooling-assisted 100% outdoor air system. The seasonal mode of operation of the proposed system is also suggested and used for estimating the Energy saving potentials. The TRNSYS 16 program integrated with a commercial equation solver is used for the Energy simulation of the proposed system, and then two existing air handling alternatives: a conventional variable air volume (VAV) system and an existing evaporative-cooling-assisted system are compared with the proposed system. The proposed system shows operating Energy savings of 82% over the conventional VAV system dur- ing the summer, and 54% and 37% in the winter and the intermediate season operations, respectively. Ultimately, the proposed system provides 68% annual operating Energy saving over the conventional VAV system, and 23% savings compared to the established evaporative-cooling-assisted system. It is also found that the extreme Energy Benefit can be obtained by enhancing the evaporative cooling effects using the liquid desiccant (LD) unit. The operating Energy saving of the LD unit can be achieved by applying the water-side free cooling and the solar thermal system. © 2014 Elsevier B.V. All rights reserved.
Alessio Polzot - One of the best experts on this subject based on the ideXlab platform.
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Energy Benefit assessment of a water loop heat pump system integrated with a co2 commercial refrigeration unit
Energy Procedia, 2017Co-Authors: Alessio Polzot, Chiara Dipasquale, Paola Dagaro, Giovanni CortellaAbstract:Abstract The improvement of Energy efficiency and the use of environmentally friendly working fluids are key elements of current European policies. Supermarkets are intensive Energy consumers and approximately the 40% of their annual Energy consumption is for refrigeration. Direct emissions of greenhouse gases associated with the use of high Global Warming Potential (GWP) refrigerants, and the indirect impact on the environment related to high electrical Energy consumption, make shopping malls not sustainable buildings. This paper analyses the Energy saving potential of integrated supermarket air conditioning and refrigeration systems using a Water Loop Heat Pump system (WLHP). A basic CO2 booster commercial refrigeration system, applied to cold rooms and display cabinets, is considered. Heat recovery from the refrigeration circuit is performed in the heating season, while in the cooling season a dry cooler on the water loop allows heat rejection to outdoors. The building and all systems are modelled in the Trnsys environment taking into account the hourly weather data, the simulated daily profiles of the cooling and heating load demand and the request from refrigerated food storage equipment. Such a model allows a thorough understanding of the potential for Energy savings with heat recovery solutions.
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Energy Benefit assessment of a water loop heat pump system integrated with a CO2 commercial refrigeration unit
Energy Procedia, 2017Co-Authors: Alessio Polzot, Paola D'agaro, Chiara Dipasquale, Giovanni CortellaAbstract:The improvement of Energy efficiency and the use of environmentally friendly working fluids are key elements of current European policies. Supermarkets are intensive Energy consumers and approximately the 40% of their annual Energy consumption is for refrigeration. Direct emissions of greenhouse gases associated with the use of high Global Warming Potential (GWP) refrigerants, and the indirect impact on the environment related to high electrical Energy consumption, make shopping malls not sustainable buildings.\ud This paper analyses the Energy saving potential of integrated supermarket air conditioning and refrigeration systems using a Water Loop Heat Pump system (WLHP), where a water loop is used as a heat source/sink for a number of electric reversible heat pumps which provide climate control on the thermal zones. A basic CO2 booster commercial refrigeration system, applied to cold rooms and display cabinets, is considered. Heat recovery from the refrigeration circuit is performed in the heating season, while in the cooling season a dry cooler on the water loop allows heat rejection to outdoors.\ud A comprehensive model of a commercial building, HVAC and refrigeration integrated systems is presented. The building and all systems are modelled in the Trnsys environment taking into account the hourly weather data, the simulated daily profiles of the cooling and heating load demand and the request from refrigerated food storage equipment. Such a model allows a thorough understanding of the potential for Energy savings with heat recovery solutions. This work is developed in the framework of CommONEnergy, an EU project funded by the European Community within the Seventh Framework Programme (FP7/2007-2013) that aims at reducing Energy consumption in shopping malls
Jasper Goseling - One of the best experts on this subject based on the ideXlab platform.
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ISIT - On the Energy Benefit of compute-and-forward for multiple unicasts
2016 IEEE International Symposium on Information Theory (ISIT), 2016Co-Authors: Jasper Goseling, Jos H. Weber, Michael GastparAbstract:Compute-and-forward (CF) is a technique which exploits broadcast and superposition in wireless networks. In this paper, the CF Energy Benefit is studied for networks with unicast sessions and modeled by connected graphs. This Benefit is defined as the ratio of the minimum Energy consumption by traditional routing techniques, not using broadcast and superposition features, and the corresponding CF consumption. It is shown to be upper bounded by min(d, K, 12√K), where d and K are the average hop-count distance and the number of sessions, respectively. Also, it can be concluded that the Energy Benefit of network coding (NC) is also upper bounded by the same value, which is a new scaling law of the Energy Benefit for NC as a function of K.
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On the Energy Benefit of compute-and-forward on the hexagonal lattice
2014Co-Authors: Zhijie Ren, Jos H. Weber, Jasper Goseling, Michael GastparAbstract:We study the Energy Benefit of applying compute-and-forward on a wireless hexagonal lattice network with multiple unicast sessions with a specific session placement. Two compute-and-forward based transmission schemes are proposed, which allow the relays to exploit both the broadcast and superposition nature of the wireless network. The Energy consumption of both transmission and reception of the nodes are taken into account. We show that with our schemes, the total Energy consumption of the network is significantly reduced compared to traditional routing based transmission schemes. Moreover, our schemes also outperform the plain network coding based transmission scheme in terms of power saving as long as the receive Energy of the devices is not negligible.
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Lower Bounds on the Maximum Energy Benefit of Network Coding for Wireless Multiple Unicast
EURASIP Journal on Wireless Communications and Networking, 2010Co-Authors: Jasper Goseling, Ryutaroh Matsumoto, Tomohiko Uyematsu, Jos H. WeberAbstract:We consider the Energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the Benefit of network coding, defined as the maximum of the ratio of the minimum Energy required by routing and network coding solutions, where the maximum is over all configurations. It is shown that if coding and routing solutions are using the same transmission range, the Benefit in d -dimensional networks is at least . Moreover, it is shown that if the transmission range can be optimized for routing and coding individually, the Benefit in 2-dimensional networks is at least 3. Our results imply that codes following a decode-and-recombine strategy are not always optimal regarding Energy efficiency.
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ISIT - On the Energy Benefit of network coding for wireless multiple unicast
2009 IEEE International Symposium on Information Theory, 2009Co-Authors: Jasper Goseling, Ryutaroh Matsumoto, Tomohiko Uyematsu, Jos H. WeberAbstract:We consider Energy savings offered by network coding for multiple unicast in wireless networks. For d-dimensional wireless networks we show that the maximum possible Benefit is at least 2d/⌊√d⌋
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Energy Benefit of Network Coding for Multiple Unicast in Wireless Networks
arXiv: Information Theory, 2008Co-Authors: Jasper Goseling, Jos H. WeberAbstract:We show that the maximum possible Energy Benefit of network coding for multiple unicast on wireless networks is at least 3. This improves the previously known lower bound of 2.4 from [1].