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See detailPoverty Profiles and Well-Being: Panel Evidence from Germany
D'Ambrosio, Conchita UL; Clark, Andrew; Ghislandi, Simone

in Research on Economic Inequality (2015), 23

We consider the link between poverty and subjective well-being, and focus in particular on the role of time. We use panel data on 49,000 individuals living in Germany from 1992 to 2012 to uncover three ... [more ▼]

We consider the link between poverty and subjective well-being, and focus in particular on the role of time. We use panel data on 49,000 individuals living in Germany from 1992 to 2012 to uncover three empirical relationships. First, life satisfaction falls with both the incidence and intensity of contemporaneous poverty. Second, poverty scars: those who have been poor in the past report lower life satisfaction today, even when out of poverty. Last, the order of poverty spells matters: for a given number of years in poverty, satisfaction is lower when the years are linked together. As such, poverty persistence reduces well-being. These effects differ by population subgroups. [less ▲]

Detailed reference viewed: 380 (16 UL)
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See detailPoverty, government transfers, and the business cycle: Evidence for the United States
Herzer, D.; Klump, Rainer UL

in Applied Econometrics and International Development (2009), 9(2), 127-147

We examine the impact of government transfers and the business cycle on poverty in the United States in the context of a poverty function that includes the official poverty rate, three types of government ... [more ▼]

We examine the impact of government transfers and the business cycle on poverty in the United States in the context of a poverty function that includes the official poverty rate, three types of government transfers, real wages, the number of female-headed families, and a business cycle variable. Using cointegration techniques, we find - contrary to most previous studies - that government transfer programs play an important poverty-reducing role. In addition, the findings suggest that the business cycle is one of the key variables in explaining poverty in the US. Furthermore, the empirical results show that the size and composition of public transfer payments change over the business cycle. We also find poverty to have a significant effect on government transfers, the business cycle, and the structure of households. [less ▲]

Detailed reference viewed: 27 (1 UL)
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See detailPowder diffraction and crystal structure prediction identify four new coumarin polymorphs
Shtukenberg, Alexander G.; Zhu, Qiang; Carter, Damien J. et al

in Chemical Science (2017)

Coumarin, a simple, commodity chemical isolated from beans in 1820, has, to date, only yielded one solid state structure. Here, we report a rich polymorphism of coumarin grown from the melt. Four new ... [more ▼]

Coumarin, a simple, commodity chemical isolated from beans in 1820, has, to date, only yielded one solid state structure. Here, we report a rich polymorphism of coumarin grown from the melt. Four new metastable forms were identified and their crystal structures were solved using a combination of computational crystal structure prediction algorithms and X-ray powder diffraction. With five crystal structures, coumarin has become one of the few rigid molecules showing extensive polymorphism at ambient conditions. We demonstrate the crucial role of advanced electronic structure calculations including many-body dispersion effects for accurate ranking of the stability of coumarin polymorphs and the need to account for anharmonic vibrational contributions to their free energy. As such, coumarin is a model system for studying weak intermolecular interactions, crystallization mechanisms, and kinetic effects. [less ▲]

Detailed reference viewed: 218 (3 UL)
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See detailPower Allocation and Bit Loading for Spatial Multiplexing in MIMO Systems
Zhang, Xi; Ottersten, Björn UL

in Proceedings IEEE International Conference on Acoustics, Speech, and Signal Processing (2003)

The power assignment problem is important for Multiple-Input-Multiple-Output (MIMO) systems to achieve high capacity. Although this problem is solved by well-known water filling algorithms, this does not ... [more ▼]

The power assignment problem is important for Multiple-Input-Multiple-Output (MIMO) systems to achieve high capacity. Although this problem is solved by well-known water filling algorithms, this does not provide an optimal solution if the system is constrained to a fixed raw bit error rate threshold and to discrete modulation s. In this work an approximate approach, called QoS based WF, is proposed to solve the power assignment problem with such constrains. It is shown to outperform quantization of the conventional water filling solution and a well known bit loading algorithm (Chow's algorithm) used in the Digital Subscriber Lines (DSL). [less ▲]

Detailed reference viewed: 17 (0 UL)
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See detailPower Allocation for Energy Efficiency Maximization in Downlink CoMP Systems With NOMA
Liu, Zhengxuan; Kang, Guixia; Lei, Lei UL et al

in IEEE Wireless Communications and Networking Conference (WCNC), 2017 (2017, March 19)

This paper investigates a power allocation problem for maximizing energy efficiency (EE) in downlink Coordinated Multi-Point (CoMP) systems with non-orthogonal multiple access (NOMA). First, users’ ... [more ▼]

This paper investigates a power allocation problem for maximizing energy efficiency (EE) in downlink Coordinated Multi-Point (CoMP) systems with non-orthogonal multiple access (NOMA). First, users’ achievable data rate and network throughput are analysed under three transmission schemes: 1) all users’ signals are jointly transmitted by coordinated base stations (BSs); 2) only cell-edge users’ signals are jointly transmitted by coordinated BSs; 3) each user’s signals are transmitted by only one BS. Next, we formulate EE maximization problems for the three schemes under the constraints of minimum users’ data rate and maximum BS transmit power. The considered problem is non-convex and hard to tackle. To address it, an iterative sub-optimal algorithm is proposed by adopting fractional programming and difference of convex programming. Numerical results show that the near optimality performance of EE can be achieved by using the proposed algorithm with advantages of fast convergence and low complexity. Three transmission schemes of NOMA have superior EE performance compared with conventional orthogonal multiple access scheme in the same CoMP networks. [less ▲]

Detailed reference viewed: 251 (32 UL)
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See detailPower Allocation for Energy-Constrained Cognitive Radios in the Presence of an Eavesdropper
Maleki, Sina UL; Kalantari, Ashkan UL; Chatzinotas, Symeon UL et al

in 2014 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP) (2014, May)

Reliable and agile spectrum sensing as well as secure communication are key requirements of a cognitive radio system. In this paper, secrecy throughput of a cognitive radio is maximized in order to ... [more ▼]

Reliable and agile spectrum sensing as well as secure communication are key requirements of a cognitive radio system. In this paper, secrecy throughput of a cognitive radio is maximized in order to determine the sensing threshold, the sensing time, and the transmission power. Constraints of the problem are defined as a lower-bound on the detection probability, an upper-bound on the average energy consumption per time-frame, and the maximum transmission power of the cognitive radio. We show that the problem can be solved by an on-off strategy where the cognitive radio only performs sensing and transmits data if the cognitive channel gain is greater than the average eavesdropper channel gain. The problem is then solved by a line-search over sensing time. Eventually, the secrecy throughput of the cognitive radio is evaluated employing the IEEE 802.15.4/ZigBee standard. [less ▲]

Detailed reference viewed: 159 (4 UL)
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See detailPower Allocation for In-Band Full-Duplex Self-Backhauling
Lagunas, Eva UL; Lei, Lei UL; Maleki, Sina UL et al

in International Conference on Telecommunications and Signal Processing (TSP), Barcelona, Spain, July 2017 (2017, July)

Detailed reference viewed: 197 (25 UL)
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See detailPower Allocation in Multibeam Satellite Systems: A Two-Stage Multi-Objective Optimization
Aravanis, Alexis; Shankar, Bhavani UL; Arapoglou, Pantelis-Daniel et al

in IEEE Transactions on Wireless Communications (2015)

Detailed reference viewed: 353 (24 UL)
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See detailPower allocation in Multibeam satellites - A hybrid-Genetic Algorithm approach
Aravanis, Alexis; Shankar, Bhavani UL; Danoy, Grégoire UL et al

in ESA Workshop on Advanced Flexible Telecom Payloads (2012)

Detailed reference viewed: 256 (26 UL)
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See detailPower and Direction of Transmission Estimation for a Directive Source: Identifiability Analysis and Estimation Algorithm
Maleki, Sina UL; Ciblat, Philippe; Shankar, Bhavani UL et al

in 2016 IEEE Sensor Array and Multichannel Signal Processing Workshop (SAM) (2016)

Reliable spectrum cartography of directive sources depends on an accurate estimation of the direction of transmission (DoT) as well as the transmission power. Joint estimation of power and DoT of a ... [more ▼]

Reliable spectrum cartography of directive sources depends on an accurate estimation of the direction of transmission (DoT) as well as the transmission power. Joint estimation of power and DoT of a directive source using ML estimation techniques is considered in this paper. We further analyze the parametric identifiability conditions of the problem, develop the estimation algorithm, and derive the Cramer-Rao-Bound (CRB). [less ▲]

Detailed reference viewed: 205 (9 UL)
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See detailPower and Flow Assignment for 5G Integrated Terrestrial-Satellite Backhaul Networks
Lagunas, Eva UL; Lei, Lei UL; Chatzinotas, Symeon UL et al

in IEEE Wireless Communications and Networking Conference, Marrakech, Morocco, April 2019 (2019)

Detailed reference viewed: 134 (26 UL)
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See detailPower and Load Optimization in Interference-Coupled Non-Orthogonal Multiple Access Networks
Lei, Lei UL; You, Lei; Yang, Yang UL et al

in IEEE Global Communications Conference (GLOBECOM) 2018 (2018, December)

Detailed reference viewed: 182 (24 UL)
See detailPower and mutuality in George Eliot's Middlemarch
Weber, Jean-Jacques UL; Hastert, Marie-Paule; Toolan, Michael

in Language, Text and Context (1992)

Detailed reference viewed: 110 (1 UL)
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See detailPower and Rate Allocation in Cognitive Satellite Uplink Networks
Lagunas, Eva UL; Maleki, Sina UL; Chatzinotas, Symeon UL et al

in IEEE International Conference on Communications, ICC 2016 (2016)

In this paper, we consider the cognitive satellite uplink where satellite terminals reuse frequency bands of Fixed-Service (FS) terrestrial microwave links which are the incumbent users in the Ka 27.5-29 ... [more ▼]

In this paper, we consider the cognitive satellite uplink where satellite terminals reuse frequency bands of Fixed-Service (FS) terrestrial microwave links which are the incumbent users in the Ka 27.5-29.5 GHz band. In this scenario, the transmitted power of the cognitive satellite terminals has to be controlled so as to satisfy the interference constraints imposed by the incumbent FS receivers. We investigate and analyze a set of optimization frameworks for the power and rate allocation problem in the considered cognitive satellite scenario. The main objective is to shed some light on this rather unexplored scenario and demonstrate feasibility of the terrestrial-satellite co-existence. In particular, we formulate a multi-objective optimization problem where the rates of the satellite terminals form the objective vector and derive a general iterative framework which provides a Pareto-optimal solution. Next, we transform the multi-objective optimization problem into different single-objective optimization problems, focusing on popular figures of merit such as the sumrate or the rate fairness. Supporting results based on numerical simulations are provided which compare the different proposed approaches. [less ▲]

Detailed reference viewed: 307 (27 UL)
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See detailPower Comparison of Cloud Data Center Architectures
Ruiu, Pietro; Bianco, Andrea; Fiandrino, Claudio UL et al

in IEEE International Conference on Communications (ICC), Kuala Lumpur, Malaysia, 2016 (2016, May)

Power consumption is a primary concern for cloud computing data centers. Being the network one of the non- negligible contributors to energy consumption in data centers, several architectures have been ... [more ▼]

Power consumption is a primary concern for cloud computing data centers. Being the network one of the non- negligible contributors to energy consumption in data centers, several architectures have been designed with the goal of improv- ing network performance and energy-efficiency. In this paper, we provide a comparison study of data center architectures, covering both classical two- and three-tier design and state-of-art ones as Jupiter, recently disclosed by Google. Specifically, we analyze the combined effect on the overall system performance of different power consumption profiles for the IT equipment and of different resource allocation policies. Our experiments, performed in small and large scale scenarios, unveil the ability of network-aware allocation policies in loading the the data center in a energy-proportional manner and the robustness of classical two- and three-tier design under network-oblivious allocation strategies. [less ▲]

Detailed reference viewed: 217 (8 UL)
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See detailPower consumption in spatial cognition
Alodeh, Maha UL; Zorba, Nizar; Verikoukis, Christos

in Transactions on Emerging Telecommunications Technologies (2013)

Detailed reference viewed: 109 (18 UL)
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See detailPower Control for Satellite Uplink and Terrestrial Fixed-Service Co-existence in Ka-band
Lagunas, Eva UL; Sharma, Shree Krishna UL; Maleki, Sina UL et al

in IEEE Vehicular Technology Conference, Boston 6-9 Sept 2015 (2015, September)

Detailed reference viewed: 263 (15 UL)
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See detailPower Control in Cognitive Radio Networks Using Cooperative Modulation and Coding Classification
Tsakmalis, Anestis UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in Proceedings of 10th International Conference on Cognitive Radio Oriented Wireless Networks (CROWNCOM) 2015 (2015)

In this paper, a centralized Power Control (PC) scheme aided by interference channel gain learning is proposed to allow a Cognitive Radio (CR) network to access the frequency band of a Primary User (PU ... [more ▼]

In this paper, a centralized Power Control (PC) scheme aided by interference channel gain learning is proposed to allow a Cognitive Radio (CR) network to access the frequency band of a Primary User (PU) operating based on an Adaptive Coding and Modulation (ACM) protocol. The main idea is the CR network to constantly probe the band of the PU with intelligently designed aggregated interference and sense whether the Modulation and Coding scheme (MCS) of the PU changes in order to learn the interference channel gains. The coordinated probing is engineered by the Cognitive Base Station (CBS), which assigns appropriate CR power levels in a binary search way. Subsequently, each CR applies a Modulation and Coding Classification (MCC) technique and sends the sensing information through a control channel to the CBS, where all the MCC information is combined using a fusion rule to acquire an MCS estimate of higher accuracy and monitor the probing impact to the PU MCS. After learning the normalized interference channel gains towards the PU, the CBS selects the CR power levels to maximize total CR network throughput while preserving the PU MCS and thus its QoS. The effectiveness of the proposed technique is demonstrated through numerical simulations. [less ▲]

Detailed reference viewed: 150 (11 UL)
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See detailPower control in cognitive radio networks using cooperative modulation and coding classification
Tsakmalis, Anestis UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST (2015), 156

In this paper, a centralized Power Control (PC) scheme aided by interference channel gain learning is proposed to allow a Cognitive Radio (CR) network to access the frequency band of a Primary User (PU ... [more ▼]

In this paper, a centralized Power Control (PC) scheme aided by interference channel gain learning is proposed to allow a Cognitive Radio (CR) network to access the frequency band of a Primary User (PU) operating based on an Adaptive Coding and Modulation (ACM) protocol. The main idea is the CR network to constantly probe the band of the PU with intelligently designed aggregated interference and sense whether the Modulation and Coding scheme (MCS) of the PU changes in order to learn the interference channels. The coordinated probing is engineered by the Cognitive Base Station (CBS), which assigns appropriate CR power levels in a binary search way. Subsequently, each CR applies a Modulation and Coding Classification (MCC) technique and sends the sensing information through a control channel to the CBS, where all the MCC information is combined using a fusion rule to acquire an MCS estimate of higher accuracy and monitor the probing impact to the PU MCS. After learning the normalized interference channel gains towards the PU, the CBS selects the CR power levels to maximize total CR network throughput while preserving the PU MCS and thus its QoS. The effectiveness of the proposed technique is demonstrated through numerical simulations. © Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2015. [less ▲]

Detailed reference viewed: 202 (5 UL)
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See detailA Power Efficient Genetic Algorithm for Resource Allocation in Cloud Computing Data Centers
Portaluri, Giuseppe; Giordano, Stefano; Kliazovich, Dzmitry UL et al

in IEEE International Conference on Cloud Networking (CLOUDNET), Luxembourg City, 2014. (2014)

Detailed reference viewed: 136 (1 UL)