158 research outputs found
A Game-Theoretic Approach to Energy-Efficient Resource Allocation in Device-to-Device Underlay Communications
Despite the numerous benefits brought by Device-to-Device (D2D)
communications, the introduction of D2D into cellular networks poses many new
challenges in the resource allocation design due to the co-channel interference
caused by spectrum reuse and limited battery life of User Equipments (UEs).
Most of the previous studies mainly focus on how to maximize the Spectral
Efficiency (SE) and ignore the energy consumption of UEs. In this paper, we
study how to maximize each UE's Energy Efficiency (EE) in an
interference-limited environment subject to its specific Quality of Service
(QoS) and maximum transmission power constraints. We model the resource
allocation problem as a noncooperative game, in which each player is
self-interested and wants to maximize its own EE. A distributed
interference-aware energy-efficient resource allocation algorithm is proposed
by exploiting the properties of the nonlinear fractional programming. We prove
that the optimum solution obtained by the proposed algorithm is the Nash
equilibrium of the noncooperative game. We also analyze the tradeoff between EE
and SE and derive closed-form expressions for EE and SE gaps.Comment: submitted to IET Communications. arXiv admin note: substantial text
overlap with arXiv:1405.1963, arXiv:1407.155
Contact Analysis of Separation Between Concrete Slab and Cushion Layer in Tianshengqiao Concrete-Faced Rockfill Dam
Tianshengqiao concrete-faced rockfill dam (CFRD), with a maximum height of 178m, is the highest dam of the same kind in China and the second highest in the world. During the construction of the dam, some problems special for high CFRDs occurred, such as deficient of cushion layer and separation of concrete slab from cushion layer. In this paper, a finite element analysis is made to understand the deformation of the cushion layer and the separation between the slab and the cushion. Direct constraints method and Coulomb friction law are used to simulate the contact behavior between the deformable concrete slab and the cushion layer. The methods are shown to be effective through a comparison of the numerical results with in-situ measurements. The mechanism of occurrence of the separation between the slab and the cushion is discussed. Valuable suggestions are made for further design and construction of high concrete-faced rockfill dams
3D Path Planning and Obstacle Avoidance Algorithms for Obstacle-Overcoming Robots
This article introduces a multimodal motion planning (MMP) algorithm that
combines three-dimensional (3-D) path planning and a DWA obstacle avoidance
algorithm. The algorithms aim to plan the path and motion of
obstacle-overcoming robots in complex unstructured scenes. A novel A-star
algorithm is proposed to combine the characteristics of unstructured scenes and
a strategy to switch it into a greedy best-first strategy algorithm. Meanwhile,
the algorithm of path planning is integrated with the DWA algorithm so that the
robot can perform local dynamic obstacle avoidance during the movement along
the global planned path. Furthermore, when the proposed global path planning
algorithm combines with the local obstacle avoidance algorithm, the robot can
correct the path after obstacle avoidance and obstacle overcoming. The
simulation experiments in a factory with several complex environments verified
the feasibility and robustness of the algorithms. The algorithms can quickly
generate a reasonable 3-D path for obstacle-overcoming robots and perform
reliable local obstacle avoidance under the premise of considering the
characteristics of the scene and motion obstacles.Comment: 2nd IEEE International Conference on Electronic Communications,
Internet of Things and Big Data Conference 2022 (IEEE ICEIB 2022
Biogenesis of iron–sulfur clusters and their role in DNA metabolism
Iron–sulfur (Fe/S) clusters (ISCs) are redox-active protein cofactors that their synthesis, transfer, and insertion into target proteins require many components. Mitochondrial ISC assembly is the foundation of all cellular ISCs in eukaryotic cells. The mitochondrial ISC cooperates with the cytosolic Fe/S protein assembly (CIA) systems to accomplish the cytosolic and nuclear Fe/S clusters maturation. ISCs are needed for diverse cellular functions, including nitrogen fixation, oxidative phosphorylation, mitochondrial respiratory pathways, and ribosome assembly. Recent research advances have confirmed the existence of different ISCs in enzymes that regulate DNA metabolism, including helicases, nucleases, primases, DNA polymerases, and glycosylases. Here we outline the synthesis of mitochondrial, cytosolic and nuclear ISCs and highlight their functions in DNA metabolism
Exploring the Use of Large Language Models for Reference-Free Text Quality Evaluation: A Preliminary Empirical Study
Evaluating the quality of generated text is a challenging task in natural
language processing. This difficulty arises from the inherent complexity and
diversity of text. Recently, OpenAI's ChatGPT, a powerful large language model
(LLM), has garnered significant attention due to its impressive performance in
various tasks. Therefore, we present this report to investigate the
effectiveness of LLMs, especially ChatGPT, and explore ways to optimize their
use in assessing text quality. We compared three kinds of reference-free
evaluation methods based on ChatGPT or similar LLMs. The experimental results
prove that ChatGPT is capable to evaluate text quality effectively from various
perspectives without reference and demonstrates superior performance than most
existing automatic metrics. In particular, the Explicit Score, which utilizes
ChatGPT to generate a numeric score measuring text quality, is the most
effective and reliable method among the three exploited approaches. However,
directly comparing the quality of two texts using ChatGPT may lead to
suboptimal results. We hope this report will provide valuable insights into
selecting appropriate methods for evaluating text quality with LLMs such as
ChatGPT.Comment: Technical Report, 13 page
Modeling and Evolutionary Optimization on Multilevel Production Scheduling: A Case Study
Multilevel production scheduling problem is a typical combinatorial
optimization problem in a manufacturing system, which is
traditionally modeled as several hierarchical sublevel problems and optimized
at each level, respectively. An integrated model, which can cope
with the whole multilevel scheduling information simultaneously, is proposed
in this paper, and a specific evolutionary algorithm is designed
to solve the integrated model with a twin-screw coding strategy. In order
to evaluate the performance of the new algorithm, a real 3-level production
scheduling problem is employed for case study, and two typical
metaheuristic algorithms, a genetic algorithm (GA) and a simulated
annealing (SA), are also employed for comparison study. Experimental
simulation results show that our proposed modeling and optimization
method has outperformed the other ones
A Benchmark for Text Expansion: Datasets, Metrics, and Baselines
This work presents a new task of Text Expansion (TE), which aims to insert
fine-grained modifiers into proper locations of the plain text to concretize or
vivify human writings. Different from existing insertion-based writing
assistance tasks, TE requires the model to be more flexible in both locating
and generation, and also more cautious in keeping basic semantics. We leverage
four complementary approaches to construct a dataset with 12 million
automatically generated instances and 2K human-annotated references for both
English and Chinese. To facilitate automatic evaluation, we design various
metrics from multiple perspectives. In particular, we propose Info-Gain to
effectively measure the informativeness of expansions, which is an important
quality dimension in TE. On top of a pre-trained text-infilling model, we build
both pipelined and joint Locate&Infill models, which demonstrate the
superiority over the Text2Text baselines, especially in expansion
informativeness. Experiments verify the feasibility of the TE task and point
out potential directions for future research toward better automatic text
expansion
A method for protein extraction from different subcellular fractions of laticifer latex in Hevea brasiliensis compatible with 2-DE and MS
<p>Abstract</p> <p>Background</p> <p>Proteomic analysis of laticifer latex in <it>Hevea brasiliensis </it>has been received more significant attentions. However, the sticky and viscous characteristic of rubber latex as cytoplasm of laticifer cells and the complication of laticifer latex membrane systems has made it challenge to isolate high-quality proteins for 2-DE and MS.</p> <p>Results</p> <p>Based on the reported Borax/PVPP/Phenol (BPP) protocol, we developed an efficient method for protein preparation from different latex subcellular fractions and constructed high-resolution reference 2-DE maps. The obtained proteins from both total latex and C-serum fraction with this protocol generate more than one thousand protein spots and several hundreds of protein spots from rubber particles as well as lutoid fraction and its membranes on the CBB stained 2-DE gels. The identification of 13 representative proteins on 2-DE gels by MALDI TOF/TOF MS/MS suggested that this method is compatible with MS.</p> <p>Conclusion</p> <p>The proteins extracted by this method are compatible with 2-DE and MS. This protein preparation protocol is expected to be used in future comparative proteomic analysis for natural rubber latex.</p
Reference Ranges and Association of Age and Lifestyle Characteristics with Testosterone, Sex Hormone Binding Globulin, and Luteinizing Hormone among 1166 Western Chinese Men
Decreased total testosterone (TT) is the recommended metric to identify age-related hypogonadism. However, average TT and the extent to which it varies by age, can vary substantially among different populations. Population-specific reference ranges are needed to understand normal versus abnormal TT levels. Therefore, the goal for this study was to describe androgen concentrations and their correlates among Western Chinese men. We completed a population-based, cross-sectional study including 227 young adults (YA) (20–39 years) and 939 older adults (OA) (40–89 years). We measured TT, sex-hormone binding globulin (SHBG), luteinizing hormone (LH), testosterone secreting index (TSI), and calculated free testosterone (cFT). Reference ranges for this population were determined using average YA concentrations. Multivariable regression models were used to predict hormone concentrations adjusting for age, waist-to-height ratio (WHR), marital status, education, occupation, smoking, alcohol, blood glucose, and blood pressure. Among OA, 3.8% had low TT, 15.2% had low cFT, 26.3% had low TSI, 21.6% had high SHBG, and 6.1% had high LH. Average cFT was significantly lower in OA (0.30 nmol/L; standard deviation (SD): 0.09) versus YA (0.37; SD: 0.11) but TT was not different in OA (16.82 nmol/L; SD: 4.80) versus YA (16.88; SD: 5.29). In adjusted models increasing age was significantly associated with increased SHBG or LH, and decreased cFT or TSI; however, TT was not significantly associated with age (β = 0.02 nmol/L; 95% confidence interval (CI): -0.01, 0.04). Higher WHR was associated with significantly decreased TT, SHBG, TSI, and LH. The only variable significantly related to cFT was age (β = -0.0033; 95% CI:-0.0037, -0.0028); suggesting that cFT measurements would not be confounded by other lifestyle factors. In conclusion, cFT, but not TT, varies with age in this population, suggesting cFT may be a better potential marker for age-related androgen deficiency than TT among Western Chinese men
Copper-based charge transfer multiferroics with a configuration
Multiferroics are materials with a coexistence of magnetic and ferroelectric
order allowing the manipulation of magnetism by applications of an electric
field through magnetoelectric coupling effects. Here we propose an idea to
design a class of multiferroics with a configuration using the magnetic
order in copper-oxygen layers appearing in copper oxide high-temperature
superconductors by inducing ferroelectricity. Copper-based charge transfer
multiferroics SnCuO2 and PbCuO2 having the inversion symmetry breaking
polar space group are predicted to be such materials. The active inner s
electrons in Sn and Pb hybridize with O states leading the buckling in
copper-oxygen layers and thus induces ferroelectricity, which is known as the
lone pair mechanism. As a result of the configuration, SnCuO2 and PbCuO2
are charge transfer insulators with the antiferromagnetic ground state of the
moment on Cu retaining some strongly correlated physical properties of parent
compounds of copper oxide high-temperature superconductors. Our work reveals
the possibility of designing multiferroics based on copper oxide
high-temperature superconductors.Comment: 18 pages, 5 figures, 1 tabl
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