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Calculations of narrow-band transimissities and the Planck mean absorption coefficients of real gases using line-by-line and statistical narrow-band models

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Frontiers in Energy 2014年第1期8卷 41-48页

作者： Huaqiang CHU Mingyan GU Huaichun ZHOU fengshan liu School of Energy and Environment Anhui University of TechnologyMa'anshan 243002 China Key Laboratory for Thermal Science and Power Engineering of Ministryof Education Tsinghua University Beijing 100084 China Insti-tute for Chemical Process and Environmental Technology NationalResearch Council Montreal Road Ottawa Ont. K1A 0R6 Canada

Narrow-band transmissivities in the spectral range of 150 to 9300 cml and at a uniform resolution of 25 cm-1 were calculated using the statistical narrow-band （SNB） model with the band parameters of Soufiani and Taine, the more recent parameters of Andr6 and Vaillon, and the line-by-line （LBL） method along with the HITEMP-2010 spectroscopic database. Calculations of narrow-band transmissivity were conducted for gas columns of different lengths and containing different isothermal and non-isothermal CO2-H20-N2 mixtures at 1 atm. Narrow-band transmissivities calculated by the SNB model are in large relative error at many bands. The more recent SNB model parameters of Andr6 and Vaillon are more accurate than the earlier parameters of Soufiani and Taine. The Planck mean absorption coefficients of CO2, H20, CO, and CH4 in the temperature range of 300 to 2500K were calculated using the LBL method and different versions of the high resolution transmission （HITRAN） and high-temperature spectroscopic absorption parameters （HITEMP） spectroscopic databases. The SNB model was also used to calculate the Planck mean absorption coefficients of these four radiating gases. The LBL results of the Planck mean absorption coefficient were compared with the classical results of Tien and those from the SNB model.

关键词： transimissity HITEMP HITRAN Planckmean absorption coefficients

Energy partitioning and environmental influence factors in different vegetation types in the GEWEX Asian Monsoon Experiment

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Frontiers of Earth Science 2014年第4期8卷 582-594页

作者： fengshan liu Fulu TAO Shenggong LI Shuai ZHANG Dengpan XIAO Meng WANG Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Geographical Sciences Hebei Academy of Sciences Shijiazhuang 050011 China

Environmental influences upon energy balance in areas of different vegetation types （i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and mixed farmland at Tak in Thailand） in the GEWEX Asian Monsoon Experiment were investigated. The sites we investigated are geographically and climatologically different; and consequently had quite large variations in temperature （T）, water vapor pressure deficit （VPD）, soil moisture （SM）, and precipitation （PPT）. During May- October, the net radiation flux （Rn）（in W·m^-2） was 406.21 at Tak, 365.57 at Kog-Ma, 390.97 at Amdo, 316.65 at Arvaikheer, and 287.10 at Yakutsk. During the growing period, the Rn partitioned into latent heat flux （2E/Rn） was greater than that partitioned into sensible heat flux （H/Rn） at Tak and at Kog-Ma. In contrast, 2E/Rn was lower than H/Rn at Arvaikheer, H/Rn was less than 2E/Rn between DOY 149 and DOY 270 at Amdo, and between DOY 165 and DOY 235 at Yakutsk. The R, partitioned into ground heat flux was generally less than 0.15. The short-wave albedo was 0.12, 0.18, and 0.20 at the forest, mixed land, and grass sites, respectively. At an hourly scale, energy partitions had no correlation with environmental factors, based on average summer half- hourly values. At a seasonal scale energy partitions were linearly correlated （usually p 〈 0.05） with T, VPD, and SM. The 2E/Rn increased with increases in SM, T, and VPD at forest areas. At mixed farmlands, ）λE/Rn generally had positive correlations with SM, T, and VPD, but was restrained at extremely high values of VPD and T. At grasslands, λE/Rn was enhanced with increases of SM and T, but was decreased with VPD.

关键词： energy balance vegetation type netradiation latent heat flux sensible heat flux short-wavealbedo GEWEX Asian Monsoon Experiment

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芦竹属菌草腋芽萌发期耐盐性评价

福建农林大学学报（自然科学版） 2024年第4期53卷 541-548页

作者：蔡杨星林冬梅曹秀明刘斌林辉罗海凌刘凤山林占熺福建农林大学国家菌草工程技术研究中心福建农林大学菌草与生态学院(碳中和学院) 福建农林大学食品科学学院福建福州350002

【目的】筛选腋芽萌发期耐盐性较强的芦竹属菌草品种,为该类菌草耐盐品种培育提供参考。【方法】以国内外不同地区的12个芦竹属菌草品种为试材,对150 mmol·L^(-1) NaCl溶液处理后腋芽萌发期的各个指标(芽长、根长、芽鲜质量、根鲜质量... 详细信息

【目的】筛选腋芽萌发期耐盐性较强的芦竹属菌草品种,为该类菌草耐盐品种培育提供参考。【方法】以国内外不同地区的12个芦竹属菌草品种为试材,对150 mmol·L^(-1) NaCl溶液处理后腋芽萌发期的各个指标(芽长、根长、芽鲜质量、根鲜质量、发芽势、发芽率、发芽指数和活力指数)进行测定。利用模糊隶属函数法和聚类分析法对供试品种的耐盐性进行综合评价。【结果】与对照组相比,在150 mmol·L^(-1) NaCl胁迫下,所有供试品种的发芽势均降低,芽长、根长、芽鲜质量和根鲜质量都减小;除LZ_NO.1、LZ_NO.3和LZ_NO.7外,其他品种的发芽率均下降;活力指数受盐胁迫的影响最大。基于各指标耐盐系数隶属函数值的临近度对12个品种进行聚类分析,结果表明:LZ_NO.1、LZ_NO.3和LZ_NO.7为一类,属高耐盐型;LZ_NO.2、LZ_NO.4和LZ_NO.6为一类,属盐敏感型。【结论】腋芽萌发期耐盐性较强的芦竹属菌草品种为LZ_NO.1、LZ_NO.3和LZ_NO.7;根据活力指数可判定芦竹属菌草品种的质量优劣。

关键词：芦竹属菌草腋芽萌发耐盐性隶属函数分析法聚类分析

Impact of thermal time shift on wheat phenology and yield under warming climate in the Huang-Huai-Hai Plain, China

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Frontiers of Earth Science 2017年第1期11卷 148-155页

作者： Dengpan XIAO Yongqing QI Zhiqiang LI Rende WANG Juana P. MOIWO fengshan liu Institute of Geographical Sciences Hebei Academy of Sciences Shijiazhuang 050011 China Key Laboratory for Agricultural Water Resources Hebei Key Laboratory for Agricultural Water-Saving Center for Agricultural Resource Research Institute of Genetics and Development Biology Chinese Academy of Sciences Shijiazhnang 050021 China Department of Agricultural Engineering School of Technology Njala University Freetown Sierra Leone Juncao Research Institute Fujian Agriculture and Forestry University Fuzhou 350002 China

Given climate change can potentially influence crop phenology and subsequent yield, an investigation of relevant adaptation measures could increase the understanding and mitigation of these responses in the future. In this study, field observations at 10 stations in the Huang- Huai-Hai Plain of China （HHHP） are used in combination with the Agricultural Production Systems Simulator （APSIM）-Wheat model to determine the effect of thermal time shift on the phenology and potential yield of wheat from 1981-2009. Warming climate speeds up winter wheat development and thereby decreases the duration of the wheat growth period. However, APSIM-Wheat model simulation suggests prolongation of the period from flowering to maturity （Gr） of winter wheat by 0.2-0.8 d·10yr^-1 as the number of days by which maturity advances, which is less than that by which flowering advances. Based on computed thermal time of the two critical growth phases of wheat, total thermal time from floral initiation to flowering （TT_floral_initiation） increasesd in seven out of the 10 investigated stations. Altematively, total thermal time from the start of grainfilling to maturity （TT_start grain_fill） increased in all investigated stations, except Laiyang. It is thus concluded that thermal time shift during the past three decades （1981- 2009） prolongs Gr by 0.2-3.0 d·10yr^-1 in the study area. This suggests that an increase in thermal time （TT） of the wheat growth period is critical for mitigating the effect of growth period reduction due to warming climatic condition. Furthermore, climate change reduces potential yield of winter wheat in 80% of the stations by 2.3-58.8 kg·yr^-1. However, thermal time shift （TTS） increases potential yield of winter wheat in most of the stations by 3.0-51.0 Received September 16, 2015; accepted January 24, 2016 kg·yr^-1. It is concluded that wheat cultivars with longer growth periods and higher thermal requirements could mitigate the negative effects of warming climate on c

关键词： adaptation thermal time shift crop phenology winter wheat warming climate

Contributions of climate, varieties, and agronomic management to rice yield change in the past three decades in China

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Frontiers of Earth Science 2016年第2期10卷 315-327页

作者： He ZHANG Fulu TAO Dengpan XIAO Wenjiao SHI fengshan liu Shuai ZHANG Yujie liu Meng WANG Huizi BAI Key Laboratory of Land Surface Pattern and Simulation Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Institute of Geographical Sciences Hebei Academy of Sciences Shijiazhuang 050011 China Juncao Research Institute Fujian Agriculture and Forestry University Fuzhou 350002 China Qufu Normal University Rizhao 276826 China

The long-term field experiment data at four representative agro-meteorological stations, together with a crop simulation model, were used to disentangle the contributions of climate change, variety renewal, and fertilization management to rice yield change in the past three decades. We found that during 1981-2009 varieties renewal increased rice yield by 16%-52%, management improvement increased yield by 0-16%, and the contribu- tions of climate change to rice yield varied from - 16% to 10%. Varieties renewal and management improvement offset the negative impacts of climate change on rice production. Among the major climate variables, decreases in solar radiation reduced rice yield on average by 0.1% per year. The impact of temperature change had an explicit spatial pattern. It increased yield by 0.04%-0.4% per year for single rice at Xinbin and Ganyu station and for late rice at Tongcheng station, by contrast reduced yield by 0.2%- 0.4% per year for single rice at Mianyang station and early rice at Tongcheng station. During 1981-2009, rice varieties renewal was characterized by increases in thermal requirements, grain number per spike and harvest index. The new varieties were less sensitive to climate change than old ones. The development of high thermal require- ments, high yield potential and heat tolerant rice varieties, together with improvement of agronomic management, should be encouraged to meet the challenges of climate change and increasing food demand in future.

关键词： adaptation climate change food security,impact cultivar management

基于模流分析的动车组轴箱轴承工程塑料保持架注塑模具浇口数量方案分析

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高速铁路新材料 2024年第4期3卷 33-39页

作者：唐继兵田少波陶国安郭德宏柏松刘凤山北京隆轩橡塑有限公司北京102402

为了优化动车组轴箱轴承工程塑料保持架注塑模具的浇口数量,预设6种浇口数量方案,利用模流分析软件,对6种方案进行模拟分析,通过熔接线位置、注射时间、最大剪切速率、流动末端压力差和翘曲位移数据对比的模流分析结果,结合保持架结构... 详细信息

为了优化动车组轴箱轴承工程塑料保持架注塑模具的浇口数量,预设6种浇口数量方案,利用模流分析软件,对6种方案进行模拟分析,通过熔接线位置、注射时间、最大剪切速率、流动末端压力差和翘曲位移数据对比的模流分析结果,结合保持架结构和功能要求,选取最优浇口设计方案。通过该案例可以了解到浇口的数量和位置对塑料件质量的重要性。在产品设计前期利用模流分析软件进行模拟,可以提前预测设计方案的优劣,缩短产品设计开发周期,减少模具的报废率,提高产品的成型质量,从而降低研发成本。

关键词：动车组轴箱轴承工程塑料保持架注塑模具浇口数量模流分析

A CLASS OF RANDOM NUMBER GENERATORS BASED ON WEYL SEQUENCE

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Applied Mathematics(A Journal of Chinese Universities) 2005年第4期20卷 483-490页

作者： Liang Heng liu Qinghua Bai fengshan Dept. of Math. Sci. Tsinghua Univ. Beijing 100084China.

The generation of good pseudo-random numbers is the base of many important fields in scientific computing, such as randomized algorithms and numerical solution of stochastic differential equations. In this paper, a class of random number generators （RNGs） based on Weyl sequence is proposed. The uniformity of those RNGs is proved theoretically. Statistical and numerical computations show the efficiency of the methods.

关键词： pseudo-random number randomized algorithm statistical test uniform distribution.

MECHANISM OF THE BASIN-MOUNTAIN METALLOGENIC SYSTEM IN HIMALAYAN PERIOD IN SANJIANG CONCENTRATION AREA,SOUTHWEST CHINA

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地学前缘 2000年第S1期7卷 425-426页

作者： liu fengshan[WT5,5”BX](China Geological Survey,MLR,Beijing 100083,China)

Sanjiang (Jinshajiang River,Lancangjiang River and Nujiang River) concentration area in southwest China is within the Tethys\|Himalayan tectonic domain,and it is the main area where develops Himalayan movement and relative ore deposits,such as Yulong super large Cu\|Mo deposit,Jinding super large Pb\|Zn deposit,etc ,in West *** it is a best place to study Himalayan movement and metallogeny.1 Metallogenic geological background Sanjiang concentration area has passed complex Tethys tectonic development before Cainozoic era,and it begins Himalayan inland basin\|mountain tectonic development at the end of Yanshan *** commonly accepts autochthonous platform type deposits since Mesozoic era,and the basin\|mountain tectonic pattern has already *** metamorphic terrains and paleo\|Tethys orogenic belts become “mountains”,as well as microplateforms sink to become “basins”.Comparing to Mesozoic basins,Eogene basins are many smaller garben\|type extension basins or strike\|slip extension basins on the background of big large basins.

关键词： Himalayan mineralization metallogenic system Sanjiang co ncentration area

he adaptive chirplet transform and its application in GPR target detection

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Applied Geophysics 2009年第2期6卷 192-200页

作者： Zeng Zhaofa Wu Fengshou Huang Ling liu fengshan Sun Jiguang Collage of Exploration Science and Technology Jilin University Changchun 130026 China Applied Mathematic Research Center Delaware State University Dover DE 19901 USA

GPR has become an important geophysical method in UXO and landmine detection, for it can detect both metal and non-metallic targets. However, it is difficult to remove the strong clutters from surface-layer reflection and soil due to the low signal to noise ratio of GPR data. In this paper, we use the adaptive chirplet transform to reject these clutters based on their character and then pick up the signal from the UXO by the transform based on the Radon-Wigner distribution. The results from the processing show that the clutter can be rejected effectively and the target response can be measured with high SNR.

关键词： GPR target detection clutter rejection chirplet transform