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Opportunities to search for extraterrestrial intelligence with the FAST

Research in Astronomy and Astrophysics 2020年第5期20卷 193-204页

作者： Di Li Vishal Gajjar Pei Wang Andrew Siemion Zhi-Song Zhang Hai-Yan Zhang You-Ling Yue Yan Zhu cheng-Jin Jin Shi-Yu Li Sabrina Berger Bryan Brzycki Jeff cobb Steve croft Daniel czech David DeBoer Julia DeMarines Jamie Drew J.Emilio Enriquez Nectaria Gizani Eric J.Korpela Howard Isaacson Matthew Lebofsky Brian Lacki David H.E.MacMahon Morgan Nanez chen-Hui Niu Xin Pei danny c.price Dan Werthimer Pete Worden Yunfan Gerry Zhang Tong-Jie Zhang FAST collaboration cAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China University of chinese Academy of Sciences Beijing 100049China Department of Astronomy University of California BerkeleyBerkeley CA 94720USA SETI Institute Mountain ViewCA 94043USA Department of Astrophysics/IMAPP Radboud UniversityNijmegenNetherlands University of Malta Institute of Space Sciences and AstronomyMalta Space Sciences Laboratory University of CaliforniaBerkeleyBerkeley CA 94720USA Breakthrough Initiatives NASA Research ParkMoffett Field CA 94043USA Hellenic Open University School of Science&TechnologyParodos AristotelousPerivola PatronGreece University of Southern Queensland QLD 4350Australia Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China centre for Astrophysics&Supercomputing Swinburne University of TechnologyHawthornVIC 3122Australia Department of Astronomy Beijing Normal UniversityBeijing 100875China Institute of Astronomical Science Dezhou UniversityDezhou 253023China

The discovery of ubiquitous habitable extrasolar planets,combined with revolutionary advances in instrumentation and observational capabilities,has ushered in a renaissance in the search for extraterrestrial intelligence(SETI).Large scale SETI activities are now underway at numerous international *** Five-hundred-meter Aperture Spherical radio Telescope(FAST)is the largest single-aperture radio telescope in the world,and is well positioned to conduct sensitive searches for radio emission indicative of *** is one of the five key science goals specified in the original FAST project plan.A collaboration with the Breakthrough Listen Initiative was initiated in 2016 with a joint statement signed both by *** Yan,the then director of National Astronomical Observatories,chinese Academy of Sciences(NAOc),and *** Worden,chairman of the Breakthrough Prize *** this paper,we highlight some of the unique features of FAST that will allow for novel SETI *** identify and describe three different signal types indicative of a technological source,namely,narrow band,wide-band artificially dispersed and modulated ***,we propose observations with FAST to achieve sensitivities never before *** nearby exoplanets,such as TESS targets,FAST will be sensitive to an EIRP of 1.9×1011 W,well within the reach of current human *** the Andromeda Galaxy,FAST will be able to detect any Kardashev type II or more advanced civilization there.

关键词： Search for Extraterrestrial Intelligence Five-hundred-meter Aperture Spherical radio Telescope

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A DIREcT SEARcH FRAME-BASED cONJUGATE GRADIENTS METHOD

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Journal of computational Mathematics 2004年第4期22卷 489-500页

作者： I.D.coope c.J.price DepartmentofMathematicsandStatistics UniversityofCanterburyPrivateBag4800ChristchurchNewZealand

A derivative-free frame-based conjugate gradients algorithm is presented. convergence is shown for c^1 functions, and this is verified in numerical trials. The algorithm is tested on a variety of low dimensional problems, some of which are ill-conditioned, and is also tested on problems of high dimension. Numerical results show that the algorithm is effective on both classes of problems. The results are compared with those from a discrete quasiNewton method, showing that the conjugate gradients algorithm is competitive. The algorithm exhibits the conjugate gradients speed-up on problems for which the Hessian at the solution has repeated or clustered eigenvalues. The algorithm is easily parallelizable.

关键词： conjugate gradients Derivative-free Frame-based methods Numerical results

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The next generation models for crops and agro-ecosystems

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Science china(Information Sciences) 2011年第3期54卷 589-597页

作者： THOLEN danny Plant Systems Biology Group CAS-MPG Partner Institute and Key Laboratory for Computational BiologyShanghai Institutes for Biological SciencesChinese Academy of Sciences

Growth in population, decrease in arable land area, and change in climate are endangering our food security. Precision agriculture has the potential to increase crop productivity thorough tailored agricultural practices for different growing areas. Many models of crops and agro-ecosystems capable of predicting interaction between plants and environments have been developed for precision agriculture. currently, there are several representative categories of crop and agro-ecosystem models, including the de Wit school models, the DSSAT series models and the APSIM series models, which have contributed substantially to improvement of agricultural practices. However, these models are weak in predicting performances of crops under environmental and genetic perturbations are generally weak, which severely limits the application of these models in guiding precision agriculture. We need to develop the next generation crop and agro-ecosystems models with a high level of mechanistic basis, which can be integrated with high throughput data and can predict the heterogeneity of environmental factors inside canopy and dynamic canopy photosynthesis. In developing such a model close collaboration is inevitably required among scientists from different disciplines. The successful development and application of such models will undoubtedly advance precision agriculture through providing better agronomical practices tailored for different growing environments. These models will also form a basis to identify breeding targets for increased productivity at given location with given soil and climatic conditions.

关键词： crop models ecosystem models crop yields nonlinear analysis photosynthesis

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现场实例证实的水平井裸眼防砂完井的设计方法

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吐哈油气 2005年第3期10卷 294-300页

作者： c.price-Smith M.Parlar 杜悫

油藏需要防砂会给合适完井方法的选取带来严重挑战。水平井裸眼完井已成功地用于这种油藏,不仅能减少出砂,还能在井的整个预期寿命期最大限度地提高产油率/注水率以及井眼出液量,并使风险和复杂性降至最小。尽管预射孔/割缝衬管和砾石... 详细信息

油藏需要防砂会给合适完井方法的选取带来严重挑战。水平井裸眼完井已成功地用于这种油藏,不仅能减少出砂,还能在井的整个预期寿命期最大限度地提高产油率/注水率以及井眼出液量,并使风险和复杂性降至最小。尽管预射孔/割缝衬管和砾石充填等各种水平井裸眼防砂完井工艺在近十年已广泛应用,文献中也讨论了许多实例,但是如何选择这些完井方式还缺乏系统方法。本文的目的就是通过综合大量的经验和认识,从全球性技术一体化的角度提出这样一个设计方法。论文首先讨论了如何确定水平井裸眼完井、何时实施防砂、用什么方法防砂、怎样在水平井中实施该方法的广义、统一的方法。影响"何时"防砂的因素包括地应力、孔隙压力降(砂岩预测值)、预期井眼寿命、产量、油气和井眼类型、总产值、砂岩允许生产能力、环境限制因素以及修井能力,所有这些因素都对总的风险分析有影响。除了前面提到的许多因素以外,影响"什么"的关键因素包括井眼结构、储层岩性和石油物性以及井底设备的可靠性。影响"如何"的参数有油藏钻井液性质、驱替和清洗方法、筛管类型、作业实施/保障(风险管理,作业时机和后勤供应)、扭矩和阻力分析、砾石充填模拟。其次,列举了应用这个方法的一系列实例,它们分别属于不同类型的水平井裸眼井底完井,包括割缝衬管、孤立筛管(包括膨胀式)、砾石充填以及各种综合清洗方法,还提出了各个公司从中吸取的教训。

关键词：水平井裸眼完井筛管砾石充填防砂技术出砂预测

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Methane dehydroaromatization–A study on hydrogen use for catalyst reduction, role of molybdenum, the nature of catalyst support and significance of Bronsted acid sites

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Journal of Energy chemistry 2019年第7期28卷 20-32页

作者： Vaidheeshwar Ramasubramanian Hema Ramsurn Geoffrey L.price Russell School of chemical Engineering The University of Tulsa

Methane dehydroaromatization was studied over Mo/SiO2 and Mo/HZSM-5 with different Mo loadings(2, 5, 10 wt%) at 973 K and 1023 K in a recirculating batch reactor. H2 pretreatment at 1023 K prior to methane activation has significantly improved the catalyst activity with increase in Mo loading and reduced the induction time on benzene formation in both Mo/SiO2 and Mo/HZSM-5. 10 wt% Mo/HZSM-5 gave a maximum methane conversion of 19% and ~67% benzene selectivity at 1023 K. The XRD analysis of used catalysts revealed that the Mo O3 species were converted to β-Mo2c phase. Studies on Mo/SiO2 catalysts showed that benzene was formed even in the absence of acidic zeolite sites. Reactions of ethylene in the presence of pure silica, HZSM-5 and in a blank reactor revealed that conversion of ethylene to aromatics was similar in case of the blank reactor and silica. Thus, it is believed that molybdenum carbide sites act as active sites only for c–H bond activation of methane and ethylene formation. Even though, ethylene can undergo subsequent oligomerization without any catalytic aid to form benzene at973 K and above addition of acidic zeolites improved the selectivity of benzene.

关键词： Methane dehydroaromatization HZSM-5 Silica Molybdenum loading H2 pretreatment Acidic function

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75.[6—双(2氯—乙基)胺基]烃基腺嘌呤类化合物

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药学进展 1961年第Z1期 8-9页

作者： Hsi Hu Lin charles c.price 赵连昌

作者基于氮芥子气[HN-2,即双（β—氯乙基）甲胺]可影响体内去氧核糖核酸（DNA）的合成借以增强其制癌作用的假說,同时为了保存其原有氮芥集团的脂肪族性质,因而采用次乙基和次丙基的支链和腺嘌吟的6—氨基相联,而未以氮芥集团直接和嘌... 详细信息

作者基于氮芥子气[HN-2,即双（β—氯乙基）甲胺]可影响体内去氧核糖核酸（DNA）的合成借以增强其制癌作用的假說,同时为了保存其原有氮芥集团的脂肪族性质,因而采用次乙基和次丙基的支链和腺嘌吟的6—氨基相联,而未以氮芥集团直接和嘌吟环相接,于是

关键词：化合物乙基链烷基

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SETI计划的百万星球搜索

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科技纵览 2021年第2期 32-37,2页

作者： danny price 不详

1960年,天文学家弗兰克•德雷克(Frank Drake)将位于美国西弗吉尼亚州绿岸国家射电天文台的射电望远镜转向了附近的两颗类日恒星,寻找来自外星的智慧社会信号。德雷克戴着一副耳机,分多次收听鲸鱼座的天仓五和波江座的天苑四信号,共计15... 详细信息

1960年,天文学家弗兰克•德雷克(Frank Drake)将位于美国西弗吉尼亚州绿岸国家射电天文台的射电望远镜转向了附近的两颗类日恒星,寻找来自外星的智慧社会信号。德雷克戴着一副耳机,分多次收听鲸鱼座的天仓五和波江座的天苑四信号,共计150个小时。

关键词：射电望远镜波江座鲸鱼座西弗吉尼亚州 SETI 德雷克弗兰克

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Deep learning vs conventional learning algorithms for clinical prediction in crohn's disease: A proof-of-concept study

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World Journal of Gastroenterology 2021年第38期27卷 6476-6488页

作者： danny con Daniel R van Langenberg Abhinav Vasudevan Department of Gastroenterology and Hepatology Eastern HealthBox Hill 3128VictoriaAustralia Faculty of Medicine Nursing and Health SciencesMonash UniversityBox Hill 3128VictoriaAustralia

BAcKGROUND Traditional methods of developing predictive models in inflammatory bowel diseases(IBD)rely on using statistical regression approaches to deriving clinical scores such as the crohn's disease(cD)activity ***,traditional approaches are unable to take advantage of more complex data structures such as repeated *** learning methods have the potential ability to automatically find and learn complex,hidden relationships between predictive markers and outcomes,but their application to clinical prediction in cD and IBD has not been explored *** To determine and compare the utility of deep learning with conventional algorithms in predicting response to anti-tumor necrosis factor(anti-TNF)therapy in *** This was a retrospective single-center cohort study of all cD patients who commenced anti-TNF therapy(either adalimumab or infliximab)from January 1,2010 to December 31,*** was defined as a c-reactive protein(cRP)compared:(1)A conventional statistical learning algorithm using multivariable logistic regression on baseline data only;(2)A deep learning algorithm using a feed-forward artificial neural network on baseline data only;and(3)A deep learning algorithm using a recurrent neural network on repeated *** performance was assessed using area under the receiver operator characteristic curve(AUc)after 10×repeated 5-fold *** A total of 146 patients were included(median age 36 years,48%male).concomitant therapy at anti-TNF commencement included thiopurines(68%),methotrexate(18%),corticosteroids(44%)and aminosalicylates(33%).After 12 mo,64%had cRPconventional learning algorithm selected the following baseline variables for the predictive model:complex disease behavior,albumin,monocytes,lymphocytes,mean corpuscular hemoglobin concentration and gamma-glutamyl transferase,and had a cross-valid

关键词： Machine learning Artificial intelligence Precision medicine Personalized medicine Deep learning

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Metabolomic Profiling in Selaginella lepidophylla at Various Hydration States Provides New Insights into the Mechanistic Basis of Desiccation Tolerance

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Molecular Plant 2013年第2期6卷 369-385页

作者： Abou Yobi Bernard W.M. Wone Wenxin Xu danny c. Alexander Lining Guo John A. Ryals Melvin J. Oliver John c. cushman Department of Biochemistry and Molecular Biology University of Nevada Reno NV 89557-0330 USA Department of Biological Sciences University of Nevada Reno NV 89557-0314 USA Metabolon Inc. 800 Capitola Drive Suite 1 Durham NC 27713 USA US Department of Agriculture-Agricultural Research Service Plant Genetic Research Unit University of Missouri Columbia MI 65211 USA

Selaginella lepidophylla is one of only a few species of spike mosses （Selaginellaceae） that have evolved des-iccation tolerance （DT） or the ability to ＇resurrect＇ from an air-dried state. In order to understand the metabolic basis of DT, S, lepidophylla was subjected to a five-stage, rehydration/dehydration cycle, then analyzed using non-biased, global metabolomics profiling technology based on Gc/MS and UHLc/MS/MS2 platforms. A total of 251 metabolites including 167 named （66.5%） and 84 （33.4%） unnamed compounds were characterized. Only 42 （16.7%） and 74 （29.5%） of compounds showed significantly increased or decreased abundance, respectively, indicating that most compounds were produced con-stitutively, including highly abundant trehalose, sucrose, and glucose. Several glycolysis/gluconeogenesis and tricarboxylic acid （TcA） cycle intermediates showed increased abundance at 100% relative water content （RWc） and 50% RWc. Vanillate, a potent antioxidant, was also more abundant in the hydrated state. Many different sugar alcohols and sugar acids were more abundant in the hydrated state. These polyols likely decelerate the rate of water loss during the drying process as well as slow water absorption during rehydration, stabilize proteins, and scavenge reactive oxygen species （ROS）. In contrast, nitrogen-rich and y-glutamyl amino acids, citrulline, and nucleotide catabolism products （e.g. allantoin） were more abundant in the dry states, suggesting that these compounds might play important roles in nitrogen remobilization during rehydration or in ROS scavenging. UV-protective compounds such as 3-（3-hydroxyphenyl）propionate, apigenin, and naringenin, were more abundant in the dry states. Most lipids were produced constitutively, with the exception of choline phosphate, which was more abundant in dry states and likely plays a role in membrane hydration and stabilization. In contrast, several poly- unsaturated fatty acids were more abundant in the hydrated states, suggestin

关键词： abiotic/environmental stress mass spectrometry metabolomics oxidative/photooxidative stress desiccationtolerance Selaginella.

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Impact of climate change on outdoor design conditions and implications to peak loads

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Building Simulation 2022年第12期15卷 2051-2065页

作者： Xujie Huo Liu Yang danny Hin Wa Li Isaac Lun Siwei Lou Yuan Shi School of Architecture&Urban Planning Shenzhen UniversityShenzhen 518060China BenYuan Design and Research center Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Architecture for Health&Well-being(in preparation) Shenzhen 518060China School of Architecture Xi’an University of Architecture and TechnologyXi’an 710055China Building Energy Research Group Department of Architecture and Civil EngineeringCity University of Hong KongHong KongChina centre for Sustainable Energy Technologies University of Nottingham Ningbo ChinaNingbo 315100China School of civil Engineering Guangzhou UniversityGuangzhou 510006China

This study exams the impact of climate change on outdoor design conditions and peak loads of five chinese cities over the five major climate zones for the winter and summer *** design dry-bulb temperature(DDBT)and the coincident wet-bulb temperature(cWBT)for two 30-year periods;1971–2000 and 1984–2013 were *** was found that the DDBT of the period 1984–2013 was higher than that of the period 1971–2000,whereas the cWBT and the corresponding outdoor enthalpy of the period 1984–2013 was lower than that of 1971–2000 at the various cumulative *** trend implies that the increment in conductive heat gain through the building envelope due to the rising temperature can be lower than the reduction in fresh air load due to the lower outdoor air *** this case,the peak cooling loads may reduce in all five cities under study,and this is different from the widely held view that global warming will lead to more stringent outdoor design conditions,higher peak cooling loads and larger heating,ventilation and air conditioning(HVAc)plants than the current or historical *** implications to the“free-cooling”of HVAc systems with enthalpy control are discussed as well.

关键词： outdoor design conditions outdoor air enthalpy climate change peak loads

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