Multiple-stacked Hybrid Plays of lacustrine source rock intervals：Case studies from lacustrine basins in China

Hydrocarbon-producing lacustrine basins are widely developed in the world, and China has a large number of lacustrine basins that have developed since the early Permian. The organic-rich shale-dominated heterogeneous source rock intervals in Chinese lacustrine basins generally contain frequent thin interbeds of stratigraphically associated sandstone, siltstone, marl, dolomite, and limestone. The concept of ‘‘Hybrid Plays＇ ＇ as put forth in this article recognizes this pattern of alternating organicrich shale and organic-lean interbeds and existence of mixed unconventional and conventional plays. Hybrid Plays in lacustrine source rock intervals present a unique closed petroleum system hosting continuous hydrocarbons.The interbedded organic-lean siliciclastic and/or carbonateplays are efficiently charged with hydrocarbons via short migration pathways from the adjacent organic-rich shale that is often also a self-sourced play. We assert ‘‘Hybrid Plays＇ ＇ provide the most realistic exploration model for targeting multiple-stacked and genetically related very tight shale, tight and conventional plays together in the entire source rock interval rather than individual plays only. The Hybrid Play model has been proven and works for a wide variety of lacustrine rift, sag and foreland basins in China.

Numerical study on wave loads and motions of two ships advancing in waves by using three-dimensional translating-pulsating source

A frequency domain analysis method based on the three-dimensional translating-pulsating （3DTP） source Green function is developed to investigate wave loads and free motions of two ships advancing on parallel course in waves. Two experiments are carried out respectively to mea- sure the wave loads and the free motions for a pair of side-by- side arranged ship models advancing with an identical speed in head regular waves. For comparison, each model is also tested alone. Predictions obtained by the present solution are found in favorable agreement with the model tests and are more accurate than the traditional method based on the three dimensional pulsating （3DP） source Green function. Numer- ical resonances and peak shift can be found in the 3DP pre- dictions, which result from the wave energy trapped in the gap between two ships and the extremely inhomogeneous wave load distribution on each hull. However, they can be eliminated by 3DTP, in which the speed affects the free sur- face and most of the wave energy can be escaped from the gap. Both the experiment and the present prediction show that hydrodynamic interaction effects on wave loads and free motions are significant. The present solver may serve as a validated tool to predict wave loads and motions of two ves- sels under replenishment at sea, and may help to evaluate the hydrodynamic interaction effects on the ships safety in replenishment operation.

Intelligent In-Vehicle Safety System Based on Yolov5

In order to reduce the occurrence of traffic accidents and assist drivers to avoid dangerous driving. This paper presents a smart in-vehicle safety system that utilises the Yolov5 algorithm. Yolov5 algorithm is used to anticipate driver fatigue and distraction behaviours, and remind drivers to pay attention to safe driving in time. The system continuously splits the frames and analyses the frame content through the video feedback from the front camera, compared to the traditional machine learning, Yolov5’s mosaic data is enhanced, resulting in a batch size enhancement of 92.3%, and it also uses the Drop Block mechanism to prevent overfitting. The hardware of this system uses STM32 microcontroller and uses system DMA interrupt control and buzzer alarm device to warn about dangerous driving behaviour.

Cross-Correlation Detection of Point Sources in the WMAP First Year Data

We apply a Cross-Correlation （CC） method developed previously for detecting gamma-ray point sources to the WMAP first year data by using the Point-Spread Function of WMAP and obtain a full sky CC coefficient map. We find that the CC method is a powerful tool to examine the WMAP foreground residuals which can be further cleaned accord- ingly. Evident foreground signals are found in the WMAP foreground cleaned maps and the Tegmark cleaned map. In this process 101 point sources are detected, and 26 of them are new sources additional to the originally listed WMAP 208 sources. We estimate the flux of these new sources and verify them by another method. As a result, a revised mask file based on the WMAP first year data is produced by including these new sources.

Source-to-Source Translation and Software Engineering

Source-to-source translation of programs from one high level language to another has been shown to be an effective aid to programming in many cases. By the use of this approach, it is sometimes possible to produce software more cheaply and reliably. However, the full potential of this technique has not yet been realized. It is proposed to make source-to-source translation more effective by the use of abstract languages, which are imperative languages with a simple syntax and semantics that facilitate their translation into many different languages. By the use of such abstract languages and by translating only often-used fragments of programs rather than whole programs, the need to avoid writing the same program or algorithm over and over again in different languages can be reduced. It is further proposed that programmers be encouraged to write often-used algorithms and program fragments in such abstract languages. Libraries of such abstract programs and program fragments can then be constructed, and programmers can be encouraged to make use of such libraries by translating their abstract programs into application languages and adding code to join things together when coding in various application languages. This approach can also improve program reliability, because it is only necessary to verify the abstract programs once instead of verifying them separately in each application language. Also, this approach makes it possible to generate code faster than programming from scratch each time. This approach is compared to the use of libraries and to other methods in current use for communication between programming languages and translation between languages.

Semiannual velocity variations around the 2008 M_w 7.9 Wenchuan Earthquake fault zone revealed by ambient noise and ACROSS active source data

We continuously monitor the long-term seismic velocity variation of one of the major ruptured faults of the devastating 2008 Mw7.9 Wenchuan earthquake in China from July 2009 to January 2012,jointly using accurately controlled routinely operated signal system active source and seismic noise-based monitoring technique.Our measurements show that the temporal velocity change is not homogeneous and highly localized in the damaged fault zone and the adjacent areas.Velocity variations from the active and passive methods are quite consistent,which both are characterized by ±0.2 % seasonal variation,with peak and trough at winter and summer,respectively.The periodic velocity variation within fault zone exhibits remarkably positive correlation with barometric pressure with stress sensitivity in the order of 10-6Pa-1,suggesting that the plausible mechanism might be the crack density variation of the shallow subsurface medium of the damaged fault zone in response to the cyclic barometric pressure loading.

Characteristics and distributions of atmospheric mercury emitted from anthropogenic sources in Guiyang, southwestern Chin

Continuous measurements of speciated atmo- spheric mercury （Hg）, including gaseous elemental mer- cury （GEM）, particulate mercury （PHg）, and reactive gaseous mercury （RGM） were conducted in Guizhou Pro- vince, southwestern China. Guiyang Power Plant （GPP）, Guiyang Wujiang Cement Plant, Guizhou Aluminum Plant （GAP）, and Guiyang Forest Park （GFP） in Guiyang were selected as study sites. Automatic Atmospheric Mercury Speciation Analyzers （Tekran 2537A） were used for GEM analysis. PHg and RGM were simultaneously collected by a manual sampling system, including elutriator, coupler/ impactor, KCl-coated annular denuder, and a filter holder. Results show that different emission sources dominate different species of Hg. The highest average GEM value was 22.2 ±28.3 ng·m-3 and the lowest 6.1 ± 3.9 ng·m-3, from samples collected at GPP and GAP, respectively. The maximum average PHg was 1984.9 pg·m-3 and the mini- mum average 55.9 pg·m-3, also from GPP and GAP, respectively. Similarly, the highest average RGM of 68.8 pg·m-3 was measured at GPP, and the lowest level of 20.5 pg·m-3 was found at GAP. We conclude that coal combustion sources are still playing a key role in GEM; traffic contributes significantly to PHg; and domestic pol- lution dominates RGM.

RELATIONSHIP BETWEEN THE 30 TO 60 DAY OSCILLATION OF ATMOSPHERIC HEAT SOURCE AND THE DROUGHT AND FLOOD EVENTS IN JUNE IN THE SOUTH OF CHINA

Based on the NCEP/NCAR reanalysis data and the observed precipitation data in the south of China from 1958 to 2000,the impact of 30 to 60 day oscillation of atmospheric heat sources on the drought and flood events in June in the south of China is discussed.During the flood(drought) events,there exists an anomalous low-frequency anticyclone(cyclone) at the low level of the troposphere over the South China Sea and the northwestern Pacific,accompanied with anomalous low-frequency heat sinks(heat sources),while there exists an anomalous low-frequency cyclone(anticyclone) with anomalous heat sources(sinks) over the area from the south of China to the south of Japan.On average,the phase evolution of the low-frequency in drought events is 7 to 11 days ahead of that in flood events in May to June in the south of China.In flood events,low-frequency heat sources and cyclones are propagated northward from the southern South China Sea,northwestward from the warm pool of the western Pacific and westward from the northwestern Pacific around 140°E,which have very important impact on the abundant rainfall in June in the south of China.However,in drought events,the northward propagations of the low-frequency heat sources and cyclones from the South China Sea and its vicinity are rather late compared with those in flood events,and there is no obvious westward propagation of the heat sources from the northwestern Pacific.The timing of the low-frequency heat source propagation has remarkable impact on the June rainfall in the south of China.

基于RISC-V的FFmpeg多媒体算法库优化策略

RISC-V处理器的广泛应用使得FFmpeg多媒体算法库在RISC-V平台上的高性能实现日益重要。提出一种基于RISC-V架构的系列优化策略,针对开源音视频多媒体FFmpeg算法库中不同特征和计算密度的算法,利用RISC-V指令集的扩展性对算法库中某些耗时的算法进行指令加速和并行优化。在深入研究RISC-V开源架构的基础上,构建一个基于RISC-V开源架构的高性能FFmpeg算法库。针对不连续访存类算法、数据依赖类算法、数据快速转换类算法,从向量单元配置、向量化访存、汇编优化、指令流水优化4个方面出发,大幅提升FFmpeg算法库在RISC-V处理器上的性能。实验结果表明,采用以上优化策略后的FFmpeg算法库在基于RISC-V架构的XT-910芯片上的性能得到明显提升,其中的不连续访存类算法、数据依赖类算法、数据快速转换类算法的加速比分别为8.20、3.67、3.62。

Source and yearly distribution of PAHs in the snow from the Hailuogou glacier of Mountain Gongga, China

Snow samples were collected over a 3-year period from 2012 to 2014 at the Hailuogou glacier of Mountain Gongga(Mt. Gongga) and analyzed for 16 priority polycyclic aromatic hydrocarbons(PAHs) using Gas Chromatography–Mass Spectrometry(GC–MS). The results show that total average levels of the 16 PAHs ranged from 452 to 290 ng·L^(-1) with a possible declining trend from 2012 to 2014. Distances between the sampling sites and the emission sources were estimated at typically less than 500 km. The results suggest that the major source of PAHs was from coal combustion, while contributions from automobile exhaust played an important role in more recent years. This finding was in agreement with the characteristics of presence of local industry, residence, and recent development of tourism of the surrounding areas.

开源软件库生态治理技术研究综述:二十年进展

在“人-机-物”三元融合、泛在计算的时代蓝海下,“开放多变”“需求多样”和“场景复杂”的软件部署和运行环境对开源软件库生态的治理技术提出了更多需求和更高期望.为进一步推动构建可信软件供应链生态,围绕泛在计算模式、打造自主可控的技术体系,聚焦于开源软件库管理生态,收集近20多年来(2001–2023)发表于软件工程领域较高影响力的学术期刊和会议的348篇论文,对开源软件库生态治理技术的研究工作进行梳理.讨论开源软件库生态的建模与分析、演化与维护、质量保证和管理等方面的工作,总结研究现状、问题、挑战与趋势.

“大学只是围绕图书馆的一组建筑,图书馆才是真正的大学”出处探源

论文探究了广为流传的引语“大学只是围绕图书馆的一组建筑,图书馆才是真正的大学”的真正出处。论文首先从《图书馆名言集》的中英文版本入手,确认了引语的原始表述。随后,作者对《南北战争:叙述》一文进行了全文检索,发现引语并未出现在该书中,从而引发了对引语真实出处的进一步探索。通过持续的追问和跨平台检索,最终在JSTOR数据库中找到了该引语的正确出处。此项发现纠正了先前的误传,同时强调了学术研究中原始资料的准确性和多源验证的重要性。

数字公共产品:概念、标准及与图书馆的相关性

作为数字经济的坚实底座,数字公共基础设施的重要性已经成为广泛共识,数字公共产品作为数字公共基础设施中的重要组成部分,对于释放数字技术和数据的全部潜力以实现可持续发展目标至关重要。文章采用文献调查法和网络调查法,探究数字公共产品的概念、标准、价值以及应用实例。数字公共产品开源、开放、共享的目标与图书馆有很强的相关性,数字公共产品赋能图书馆创新生态发展,图书馆的参与为数字公共产品的推广提供重要支撑。

高比例新能源接入下的历史策略库辅助源网荷储协同实时电压控制研究

随着“双碳”目标的推进,储能、充电桩等用户侧新型负荷设备数量增多。在此背景下,由于量测条件不满足造成的不可观测区域将直接导致传统的电压控制方法难以完成对分布式电源的精准调控。为解决上述问题,提出一种基于蜣螂优化算法(DBO)的极限学习机(ELM)构建历史策略库,用以辅助源网荷储协同实时电压控制的方法,可实现对配电网电压实时精确控制。首先介绍了基于近似灵敏度计算的电压控制方法,然后介绍了DBO改进的极限学习机和历史策略库的概念及结合应用方法,构建了以基于近似灵敏度计算的电网节点有功及无功功率为输入,母线期望电压为输出的ELM模型。模型输出的母线电压作为控制依据,进一步转换为下发的用户侧可调设备调节指令。仿真算例的结果验证了所提方法的有效性和优越性。

GC-MS法测定水源水中的半挥发性有机物

我国于2002年6月1日实施了地表水环境质量标准(GB3838-2002),其中集中式生活饮用水地表水源地特定项目中规定了68种有机污染物的监测,包括挥发性有机物(VOCs)和半挥发性有机物(SVOCs),其中半挥发性有机物的类别较多,有硝基苯、氯苯、苯胺、苯酚、有机氯农药、有机磷农药、多环芳烃和多氯联苯等有机污染物,分析方法以气相色谱为主.……

2007-2008年国外有关开源软件的研究进展述评

自20世纪90年代开源运动兴起以来,关于开源软件的研究一直吸引着产业界和学术界的广泛关注。2007-2008年,国外学者围绕开源软件的研究主要涉及开源社区、开源软件质量和开源软件应用推广等相关问题,图书馆领域对开源软件的应用研究也日益深化。

Advances in Toxicology of Nε-(carboxymethyl)-lysine(CML)

Advanced glycation end-products （AGEs） are products of non-enzymatic glycation of proteins, lipids or nucleic acids and other macromolecules. To be spe- cific, Nε-（carboxymethyl）-Iysine （CML） is one of the most important components of AGEs, which is wildly distributed in the body and can be formed in vivo or in food processing and heating processes. Previous studies have shown that CML is a ma- jor immunological epitope in AGEs and plays an important role in diabetes and its complications, as well as in the development and progression of aging. This review summarized recent advances in major source, toxicological hazard and control mea- sures of CML.

微生物源示踪技术在食品链中进行污染源追溯的研究进展

在食品链中,粪便微生物污染是诱发食源性疾病的重要途径之一,也是食品安全领域备受关注的问题。利用微生物源示踪(microbial source tracking,MST)技术对粪便微生物来源和污染情况进行追踪是解决该问题的有效手段之一。MST方法一般分为依赖数据库型方法(library-dependent methods,LDMs)和非依赖数据库型方法(library-independent methods,LIMs)2种方法,其中LIMs分为依赖培养型和非依赖培养型。在非依赖培养型方法中,以16S rRNA和宿主-微生物互作基因为特异性分子标记物建立的MST方法在食品链的污染调查中得到了广泛应用。本文对MST的基本原理及特点进行简要介绍,并着重总结近几年基于宿主特异性分子标记物的MST方法在食品链中进行污染溯源的研究进展,同时结合目前MST技术所具有的独特优势及现存不足对MST技术进行展望。

SCSC-S/Fe复合系统脱氮除磷途径及微生物群落特性

为提升再生水品质,以玉米芯耦合硫铁填料构造出固相纤维素碳源+硫铁填料复合脱氮除磷系统(简称SCSC-S/Fe复合系统),基于填料生物膜Miseq高通量测序构建了16S rRNA基因克隆文库,结合系统沉积物的X射线衍射(XRD)分析,探讨了该系统对模拟城市污水处理厂低C/N比尾水深度脱氮同步除磷特性及作用途径.结果表明,随温度升高,TN去除率逐渐增大,TP去除率增加不明显,在温度为30℃和水力停留时间HRT=9h时,NO_3^--N、TN、TP平均去除率分别为99.86%、92.70%和89.15%.固相纤维素碳源反硝化脱氮单元内具有降解纤维素类和反硝化作用类细菌分别占细菌总数的41.37%和54.02%,硫铁复合填料脱氮除磷单元内异养反硝化、硫自养反硝化和氬自养反硝化的细菌占细菌总数的91.53%;XRD结果表明,水中的PO_4^(3-)主要以FeP0_4、Fe_3(P0_4)_2·χH_20和Fe_3(P0_4)_3(0H)_2等物质形式去除.因此,复合系统脱氮以异养反硝化作用为主,协同硫自养反硝化和氢自养反硝化作用;复合系统具有"化学+生物"双重除磷作用,以化学除磷作用为主.SCSC-S/Fe复合系统实现了低C/N比城市污水处理厂尾水深度脱氮同步除磷的目的.

基于YOLOX的货运源头遥感解译标志库研究

货运源头核查是进行源头治超的关键。传统依赖于台账统计的方法费时费力,相比之下,遥感技术具有大面积覆盖等优点,利用其进行货运源头核查工作可有效提高工作效率。然而,目前尚无公开可用的货运源头遥感解译标志库,故提出一种基于YOLOX的货运源头遥感解译标志库建立方法。首先,根据货运源头核查标准,提出货运源头四类场站、四类企业解译标志库建立标准,然后基于YOLOX搭建货运源头遥感图像自动检测方法,并与专家解译结果相对比。研究结果表明,用于识别铁路货场、港口、矿石以及砂石企业的AP均在0.50以上,可实现自动化建立货运源头遥感解译标志库,为利用遥感影像进行货运源头核查提供技术支撑,显著提高源头核查工作的效率。