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中华皮肤科杂志 2024年第6期57卷 579-580页

作者：陈旭魏宇昊牛悦青 L'Oréal Research and Innovation Clichy France L'Oréal Research and Innovation Rio de Janeiro Brazil L'Oréal Research and Innovation Shanghai China L'Oréal Research and Innovation Aulnay-sous-Bois France L'Oréal Research and Innovation Chevilly-Larue France CHu Nice Department of Dermatology Université Côte d'Azur Nice France université Côte d'Azur INSERM U1065 C3M Nice France

一、引言在不同的紫外线(uV)波段中,长波uVA(uVA1,340~400nm)具有更高的皮肤穿透力,并且受气象条件和臭氧层厚度等环境参数的影响较小,因此更容易到达皮肤深部的真皮层,对细胞成分(如DNA、脂质和蛋白质)造成氧化损伤。uVA1已经越来越多... 详细信息

一、引言在不同的紫外线(uV)波段中,长波uVA(uVA1,340~400nm)具有更高的皮肤穿透力,并且受气象条件和臭氧层厚度等环境参数的影响较小,因此更容易到达皮肤深部的真皮层,对细胞成分(如DNA、脂质和蛋白质)造成氧化损伤。uVA1已经越来越多地被发现与衰老、致癌作用、多种皮肤疾病和色素问题相关。

关键词： uVA1 真皮层自身对照致癌作用皮肤疾病防晒剂遗传背景氧化损伤

The Memory-Bounded Speedup Model and Its Impacts in Computing

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Journal of Computer Science & Technology 2023年第1期38卷 64-79页

作者：孙贤和鲁潇阳 Department of Computer Science Illinois Institute of TechnologyChicago 60616U.S.A.

With the surge of big data applications and the worsening of the memory-wall problem,the memory system,instead of the computing unit,becomes the commonly recognized major concern of ***,this“memorycentric”common understanding has a humble *** than three decades ago,the memory-bounded speedup model is the first model recognizing memory as the bound of computing and provided a general bound of speedup and a computing-memory trade-off *** memory-bounded model was well received even by *** was immediately introduced in several advanced computer architecture and parallel computing textbooks in the 1990’s as a must-know for scalable *** include *** Hwang’s book“Scalable Parallel Computing”in which he introduced the memory-bounded speedup model as the Sun-Ni’s Law,parallel with the Amdahl’s Law and the Gustafson’s *** the years,the impacts of this model have grown far beyond parallel processing and into the fundamental of *** this article,we revisit the memory-bounded speedup model and discuss its progress and impacts in depth to make a unique contribution to this special issue,to stimulate new solutions for big data applications,and to promote data-centric thinking and rethinking.

关键词： memory-bounded speedup scalable computing memory-wall performance modeling and optimization data-centric design

Immediate mandibular reconstruction of a u.s. navy seal with a free fibula flap following osteoradionecrosis with pathological fracture

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中国口腔颌面外科杂志 2008年第B5期6卷 218-219页

作者： Ferguson, B Caballero, H. Cole, S. Hatt, H. Bach, K. Douglas, T. Gallus, K. Laughlin, R. Dental Department Naval Medical Center Suit 206 34800 BobWilson Dr San Diego CA 92134 U.S.A.

The number of u。S。Navy SEALs that serve within u。S。Special Operations Command (SOCOM) is fewer than 2,500; this is an extremely small number when compared to the 1.5 million total u。S。military personnel currently serving on active duty。When a highly-trained highly-specialized service person is injured or medically incapacitated, it is extremely important to return him to an operational status as soon as possible。Due to the physical requirements of these personnel, reconstruction options can be limited。We present a u。S。Navy SEAL who was diagnosed with osteoradionecrosis (ORN) and a pathologic fracture of the mandible。The gamet of reconstruction options were considered。A flee fibular flap for mandibular reconstruction allowed the surgical team to complete a one-stage reconstruction with minimized functional disability, which permitted the patient a fully operational return to the SOCOM community。Case report: A 41yo male active duty Navy personnel with a history of squamous cell cancer of the base of tongue (T1N2bM0) was diagnosed with ORN。Initial treatment consisted of the Marx-university of Miami Protocol for Hyperbaric oxygen therapy。He responded with complete soft tissue coverage of the exposed bone to the right mandible。One month later, the patient, returned to the Otolaryngology Department with recurrence of exposed bone to the right mandible。He was referred to the Oral and Maxillofacial Surgery clinic at Navy Medical Center San Diego for evaluation and treatment。Surgical debridement of right mandible to bleeding bone leaving an intact inferior border was performed。

关键词：颚修复方法整形技术腓骨放射性骨坏死

A novel reconfiguration of the solar array to enhance peak power and efficiency under partial shading conditions:experimental validation

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Clean Energy 2023年第4期7卷 824-842页

作者： Vijay Laxmi Mishra Yogesh K.Chauhan K.S.Verma EED KNIT SultanpurU.P.Pin-228118India

Non-homogeneous irradiation patterns and temperature levels immensely affect the performance of solar photovoltaic *** shading conditions on solar arrays reduce the peak power and *** paper provides a new remedy called a novel Ramanujan reconfiguration(NRR)to eliminate this physical shading problem in solar photovoltaic *** is a static-based reconfigured technique that is built using a three-diode model with the help of the MATLAB®/Simulink®*** special feature of the proposed NRR technique is that when shade occurs on the solar modules,it gets realigned in a particular row,column,diagonal,corner,centre and middle peripheral *** helps over a wide range of shade dispersion on the solar *** novel topology is tested against the conventional total cross-tied(TCT)model and recently introduced advanced reconfigured models,namely odd–even topology(OET)and Kendoku topology(KDT).The results are tested under certain shading *** proposed NRR technique increases the peak power by 4.45,2.15 and 2.17 W under the first shading condition regarding TCT,OET and *** efficiency is improved by 0.51–2.18%under the third shading condition compared with other considered models in this *** addition,NRR leads to smooth output curves under the second,third and fourth shading conditions,effectively mitigating the local power *** experimental results show the proposed enhanced performance of the novel model against the other *** Abstract Remedy for physical problem correlated with solar photovoltaics Comparison with traditional and recent solar models Conclusion:NRR has effectively handled the problem related with solar *** has improved the efficiency up to 31.44%under ***,smooth output curves under S2-S4 shows its effectiveness in mitigating the local power *** power gain at 3.94%under S4 is achieved by novel ***-time verification proves the supremacy of novel proposed model over o

关键词： efficiency partial shading conditions peak power Ramanujan reconfiguration solar array total cross-tied three-diode model

Energy-Efficient Minimum Mobile Charger Coverage for Wireless Sensor Networks

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Journal of Computer Science & Technology 2022年第4期37卷 869-887页

作者： Abdalaziz Sawwan Jie Wu Department of Computer and Information Sciences Temple UniversityPhiladelphia 19122U.S.A.

Sustaining an operational wireless sensor network (WSN) is challenging due to the persistent need of the battery-powered sensors to be charged from time to time. The procedure of exploiting mobile chargers (MCs) that traverse to the fixed sensors of the network and wirelessly transfer energy in an efficient matter has been considered widely as a promising way to tackle this challenge. An optimization problem, called the mobile charger coverage problem, arises naturally to keep all of the sensors alive with an objective of determining both the minimum number of MCs required meeting the sensor recharge frequency and the schedule of these MCs. It is shown that this optimization problem becomes NP-hard in high-dimensional spaces. Moreover, the special case of the homogeneous recharge frequency of the sensors has already been proven to have a tractable algorithm if we consider whether the 1-dimensional space is a line or a ring. In this work, we seek to find a delicate border between the tractable and the intractable problem space. Specifically, we study the special case of heterogeneous sensors that take frequencies of 1's and 2's (lifetime of 1 and 0.5 time units) on a line, conjecture the special case's NP-hardness, propose a novel brute-force optimal algorithm, and present a linear-time greedy algorithm that gives a 1.5-approximation solution for the problem. Afterwards, we introduce the energy optimization problem of the MCs with the minimized number and solve it optimally. Comprehensive simulation is conducted to verify the efficiency of using our proposed algorithms that minimize the number of MCs.

关键词： cooperative charging linear network energy optimization mobile charger wireless charging wireless sensor network

A dive into spectral inference networks: improved algorithms for self-supervised learning of continuous spectral representations

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Applied Mathematics and Mechanics(English Edition) 2023年第7期44卷 1199-1224页

作者： J.Wu S.F.WANG P.PERDIKARIS Graduate Group in Applied Mathematics and Computational Science University of Pennsylvania PhiladelphiaPA 19104U.S.A. Department of Mechanical Engineering and Applied Mechanics University of Pennsylvania PhiladelphiaPA 19104U.S.A.

We propose a self-supervising learning framework for finding the dominant eigenfunction-eigenvalue pairs of linear and self-adjoint *** represent target eigenfunctions with coordinate-based neural networks and employ the Fourier positional encodings to enable the approximation of high-frequency *** formulate a self-supervised training objective for spectral learning and propose a novel regularization mechanism to ensure that the network finds the exact eigenfunctions instead of a space spanned by the ***,we investigate the effect of weight normalization as a mechanism to alleviate the risk of recovering linear dependent modes,allowing us to accurately recover a large number of *** effectiveness of our methods is demonstrated across a collection of representative benchmarks including both local and non-local diffusion operators,as well as high-dimensional time-series data from a video *** results indicate that the present algorithm can outperform competing approaches in terms of both approximation accuracy and computational cost.

关键词： spectral learning partial differential equation(PDE) neural network slow features analysis

Tracing magma mixing in granite genesis:in situ u-Pb dating and Hf-isotope analysis of zircons

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Tracing magma mixing in granite genesis:in situ U-Pb dating ...

Addressing nonresponse bias in forest inventory change estimation using response homogeneity classifications

中国科学院地质与地球物理研究所2007学术年会

作者： Simon A.Wilde Department of Applied Geology Curtin university of Technology P.O.Box U1987PerthWA 6845Australia

In situ zircon u-Pb and Hf-isotopic data have been determined for mafic microgranular enclaves and host granitoids from the Early Cretaceous Gudaoling batholith in the Liaodong Peninsula,NE China,in order to constrain the sources and petrogenesis of *** zircon u-Pb age of the enclaves(120±1 Ma) is identical to that of the host monzogranite (120±1 Ma),establishing that the mafic and felsic magmas were *** Hf isotopic composition of the enclaves[ε(t) = +4.5 to -6.2]is distinct from the host monzogranite[ε(t)=-15.1 to -25.4],indicating that both depleted mantle and crustal sources contributed to their *** depleted mantle component was not previously revealed by geochemical and Nd and Sr isotopic studies,showing that zircon Hf isotopic data can be a powerful geochemical tracer with the potential to provide unique petrogenetic *** wallrock contamination is indicated by inherited zircons with considerably older u-Pb ages and low initial Hf isotopic *** isotopic variations in Early Cretaceous zircons rule-out simple crystal-liquid fractionation or restite unmixing as the major genetic link between enclaves and host ***,mixing of mantle-derived mafic magmas with crustal-derived felsic magmas,coupled with assimilation of wall rocks,is compatible with the data.

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Forest Ecosystems 2023年第1期10卷 125-131页

作者： James A.Westfall Mark D.Nelson u.S.Forest Service Northern Research StationYorkPAUSA u.S.Forest Service Northern Research StationSt.PaulMNUSA

Estimating amounts of change in forest resources over time is a key function of most national forest inventories(NFI). As this information is used broadly for many management and policy purposes, it is imperative that accurate estimations are made from the survey sample. Robust sampling designs are often used to help ensure representation of the population, but often the full sample is unrealized due to hazardous conditions or possibly lack of land access permission. Potentially, bias may be imparted to the sample if the nonresponse is nonrandom with respect to forest characteristics, which becomes more difficult to assess for change estimation methods that require measurements of the same sample plots at two points in time, i.e., remeasurement. To examine potential nonresponse bias in change estimates, two synthetic populations were constructed: 1) a typical NFI population consisting of both forest and nonforest plots, and 2) a population that mimics a large catastrophic disturbance event within a forested population. Comparisons of estimates under various nonresponse scenarios were made using a standard implementation of post-stratified estimation as well as an alternative approach that groups plots having similar response probabilities(response homogeneity). When using the post-stratified estimators, the amount of change was overestimated for the NFI population and was underestimated for the disturbance population, whereas the response homogeneity approach produced nearly unbiased estimates under the assumption of equal response probability within groups. These outcomes suggest that formal strategies may be needed to obtain accurate change estimates in the presence of nonrandom nonresponse.

关键词： Disturbance Post-stratification Land use conversion Sample bias

xCCL:A Survey of Industry-Led Collective Communication Libraries for Deep Learning

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Journal of Computer Science & Technology 2023年第1期38卷 166-195页

作者： Adam Weingram 李雨珂戚昊 Darren Ng 代柳瑶鲁小亿 Department of Computer Science and Engineering University of CaliforniaMercedMerced 95343U.S.A.

Machine learning techniques have become ubiquitous both in industry and academic *** model sizes and training data volumes necessitate fast and efficient distributed training *** communications greatly simplify inter-and intra-node data transfer and are an essential part of the distributed training process as information such as gradients must be shared between processing *** this paper,we survey the current state-of-the-art collective communication libraries(namely xCCL,including NCCL,oneCCL,RCCL,MSCCL,ACCL,and Gloo),with a focus on the industry-led ones for deep learning *** investigate the design features of these xCCLs,discuss their use cases in the industry deep learning workloads,compare their performance with industry-made benchmarks(i.e.,NCCL Tests and PARAM),and discuss key take-aways and interesting *** believe our survey sheds light on potential research directions of future designs for xCCLs.

关键词： collective deep learning distributed training GPuDirect RDMA(remote direct memory access)