自动建模客观分型方法在非汛期人工增雨中的应用

根据安徽省人工影响天气业务系统需要,利用NCEP 500 hPa高度场和风场格点资料及安徽省81站10年非汛期逐日降水资料,在客观分析天气形势基础上,结合预报员实践经验给出的不同系统影响安徽省时的关键区,计算机自动建模,形成逐日天气型日历,实现环流分型客观化。此方法识别条件实用,模型物理意义明确,自动化程度高,自动生成的逐日天气型日历,为安徽省非汛期人工增雨作业指挥系统提供了很好的天气预报参考依据。     

明嘉靖六年《大统历》历书的气朔推步精度

历书是历法的民用本.考察了明嘉靖六年(1527年)<大统历>历书,根据历书所颁朔日和节气时刻,以及先期恢复的<授时历>和<大统历>推步术,并利用现代天文历算结果,可考校得出:(1)历书所载朔日和节气日期、时刻确由<大统历>推得;(2)<大统历>与<授时历>推步结果存在差异,推朔平均差33.35 min或34.93 min,推气平均差86.40 min,且两者均有差1日现象;(3)<大统历>与现代推算合朔时刻的平均误差为24.50 min或44.03 min,与现代推算节气时刻的差平均为1.25 d,若扣除太阳中心差则节气推步的误差将减少到86.40 min.     

中国古代太阳中天观测及二至点测算精度

研究了元代《授时历议))所保存的天象观测和推步资料，得出：(1)在AD1277—1280年问所作的98次太阳中天观测的时刻及地平高度的绝对值平均误差分别为2．64min和6．78′．(2)6部古历——《大衍历》、《宣明历》、《纪元历》、《统天历》、《重修大明历》和《授时历》推步BC522年前的3个冬至时刻的误差范围为0．97—3．51d；而AD435—1280年间的45个冬至时刻的绝对值平均误差则分别为9．35、10．42、5．54、2．97、5．68、3．36h．(3)古代确定的AD442—1280年间的16个二至时刻的绝对值平均误差为199．59min，其中元代的误差为27．89min．     

用天文方法建立商后期甲骨文年代序列的新途径—解析殷历月法

利用对具有月龄特征的历谱规律的研究成果，以推定甲骨文的绝对年代，从而提供了建立商后期甲骨文年代序列的新方法，并给出了13版卜辞的例证，通过分析殷历月的结构，得出殷历中“二癸月”和“四癸月”的月首分别为首甲日和首癸日，初步归纳出殷历月法，月首为初三，月长等于逆望月周期，建立固定，且找到建立丑之例，置闰规律未知，已存在年终，年中置闰两种闰法。     

二十四史天象记录与陈垣历表的朔闰差异

对二十四史及《清史稿》帝纪和天文志中的全部天象记录进行了整理和计算验证,发现其中历日朔闰与陈垣《二十史朔闰表》不合27例。汇集这样的例证,对于恢复中国古代完整的实行历表,是至关重要的。     

浅谈GPS建立精密工程控制网、广播星历误差对相对定位精度的影响

通过某厂二种常规方法获得的成果与GPS网分别用广播星历（随机商用软件）、精密星历（精密软件）处理采集数据获得成果对比,研究GPS定位技术建立精密控制网和广播星历（随机软件）误差对相对定位精度的影响。     

A phenology based geo-informatics approach to map land use and land cover (2003–2013) by spatial segregation of large heterogenic river basins

Accurate information on land use and land cover (LULC) is critical for policy decisions especially for management of land and water resources’ activities in large river basins around the world. Phenology based LULC classification is the most promising approach particularly in the areas with diversified cropping patterns. Sometimes in large river basins, local climate and topography provides two different phenological information sets for the same crops in the same season. Based on accurate phenological information of the main crops in spatially segregated units, the remote sensing based classification was used to map the LULC changes for a period of 2003–2013 in the Kabul River Basin (KRB) of Afghanistan. We used remotely sensed Normalized Difference Vegetation Index (NDVI) products of Moderate-resolution Imaging Spectroradiometer (MODIS) from Terra (MOD13Q1) and Aqua (MYD13Q1) with 250 m spatial resolution for this study. The overall accuracy (mean) of the LULC classification throughout the study period was around 68.15% ± 9.45while the producer and user accuracies (mean) were 75.9 ± 11.3% and 76.4 ± 11.2%, respectively. Results show that the cropping patterns vary significantly in the spatially disaggregated units. From 2003 till 2013, the ground coverage of wheat, barley and rice was increased by 31%, 7% and 32%, respectively. Overall, there has been only 2% increment in the agricultural area across the KRB between 2003 and 2013. This relatively increased trend of land cover change has taken place as a result of partial improvement in political stability as well as investment in irrigation infrastructure and agricultural development in the region. This study further provides insight to develop new agriculture strategies in order to maintain the ecosystem required to fulfil the rising food demands.     

GPS卫星定位误差分析

GPS测量数据中包含有多种误差,按其产生的来源、性质、大小及对测量产生的影响等进行了介绍和初步分析,提出了相应的措施以便消除或削弱它们对测量结果的影响。     

Can co-management emerge spontaneously? Collaborative management in Sri Lankan shrimp aquaculture

Shrimp aquaculture in northwestern Sri Lanka shows co-management like features. To understand the reasons behind co-management and to identify the mechanisms by which co-management is carried out, the paper examines shrimp aquaculture operations in three coastal communities using a case study approach. Water from an interconnected lagoon system is the key input for shrimp ponds, but it is also the potential source of shrimp disease outbreaks that threaten all shrimp farms. Farmers try to prevent the spread of disease by co-operating to adjust the timing of water intake and wastewater release. This is done through a zonal crop calendar system which is developed and implemented by a vertically integrated institutional structure with three levels: sub-zonal/community, zonal, and national. Partnerships, overall sharing of power and authority, and learning-by-doing are key features of this collaborative management system. The case shows that adaptive co-management can develop through collaborative problem-solving over time, even in the absence of legal arrangements.     

中国最早的观象台发掘

在山西襄汾县陶寺镇附近发掘出距今约4000年的最早观象台兼祭祀台遗址,它是由观测点、夯土柱和柱间狭缝组成,用于观测日出方位变化,确定回归年长度来制订历法。模拟观测结果表明,位于东南和东北的二狭缝可准确测定冬至和夏至日期,而此二狭缝之间有10个土柱,应象征着视太阳向北和向南每位移一个土柱为一个节气。由此推之,帝尧时的历法特征是将一岁分成20个节气的阳历,上古时的阴阳五行历即十月太阳历是源于它奠定的基础。