I(L)值完全诱导空间

作者引入 I(L)值完全下半连续映射 ,研究其性质。利用 I(L)值完全下半连续映射定义I(L)值完全诱导空间 ,给出 I(L)值完全诱导空间的拓扑基的表达形式 ,证得两个 I(L)值完全诱导空间的映射是连续映射的充分必要条件 ,并建立了乘积空间的 I(L)值完全诱导空间与 I(L)值完全诱导空间的乘积空间的联系     

黄海海域陆相中生界地震反射特征及靶区优选

利用前人对黄海海域油气勘探成果，作者对北黄海盆地，南黄海盆地北部坳陷陆相中生界进行了研究。结果认为：黄海海域陆相中生界分布广、厚度大、具有良好的生、储、盖组合，是该区下步油气战略性调查的首选目标。并提出北黄海陆相中生界油气勘探应以东部凹陷为主，同时兼顾中部凹陷。南黄海北部坳陷近期油气勘探重点应选择北部凹陷和加大东北凹陷的研究力度。南黄海南部坳陷陆相中生界油气勘探重点放在南五和南七凹陷。     

褐藻酸降解菌侵染海带过程的超微结构观察

首次研究了褐藻酸降解菌侵入海带的途径，通过电镜观察，跟踪研究了褐藻酸降解菌染海带过程中海带表皮细胞壁的超微结构变化。结果表明，褐藻酸降解侵染海带的过程是首先引起海带表皮细胞壁藻胶层表面的破坏，然后引起藻胶层的断裂，并使藻胶层逐渐降解变突，最后褐藻酸降解菌通过海带细胞的壁藻胶层的断裂变突处进入海带细胞内。     

钾霞石制备体系碱性滤液的利用技术

为处理钾长石水热制备钾霞石所产生的碱性滤液,本文采用水热法,考察了氢氧化铝溶解时间、晶化时间、晶化温度、水碱比对钾霞石产率和白度的影响,并对合成钾霞石物相进行了表征。结果表明,合成钾霞石的最佳条件为,氢氧化铝溶解时间为1.5 h,晶化时间为4 h,晶化温度280℃,水碱比为1.8。XRD结果表明,产物为钾霞石粉体。傅里叶变换红外光谱表明,Al(OH)₃中的Al在水热条件下进入到Si—O骨架中形成了Si—O—Al官能团,从而印证了钾霞石的合成。差热分析结果表明,合成钾霞石具有良好的热稳定性。氮气吸附结果表明,合成钾霞石比表面积为5.18 m²/g,平均孔径为32.98 nm。实现了钾长石水热制备钾霞石所剩碱性滤液的资源化利用,并为钾长石水热制备钾霞石提供了一种母液循环的思路,使水热制备钾霞石工业化成为一种可能。     

福建平潭虎潮山滑坡成因机理分析与评价

虎潮山滑坡位于平宏公路12k 704~12k 884段北侧山坡体上,是平潭海岛通往陆地的唯一公路通道。论文通过定性的工程地质分析和定量计算评价了虎潮山坡体稳定性的变化趋势,提出改建公路超挖深切坡脚和持续长时间强降雨导致的孔隙水压力作用是边坡发生滑动破坏的主要因素。     

基于数据手套和跟踪器的虚拟手臂建模

文中利用数据手套和跟踪器获取手臂各关节运动数据,根据关节运动限制对所获取数据进行处理,建立了符合人体运动规律的虚拟手臂数学模型,实现了虚拟环境中与试验者的手臂同步运动、效果逼真的虚拟手臂模型.     

虚拟现实技术在矿物数字博物馆中的应用

详细介绍基于照片的虚拟现实技术在矿物数字博物馆中的实现方法和应用,并对VRML与基于照片的虚拟现实技术进行分析研究,进而对两种实现方法的发展方向和应用前景提出见解。     

Operational feasibility of neural-network-based radar rainfall estimation

An operational radar rainfall estimation system based on the adaptive radial basis function (RBF) neural network is developed. During the process of training and cross validation, the rainfall estimation was computed only at the gauge locations. Once the training is done, the radar rainfall estimation based on neural networks is applied to the full coverage area of the radar. Such large-scale application of the rainfall estimate poses several questions in the context of operational applications. This letter addresses two of those questions, namely: 1) the feasibility of adaptively updating RBF neural network models on a daily basis and 2) the ability of neural network radar rainfall estimation at high spatial resolution within reasonable and practical time frame for operational applications. Using the datasets collected by WSR-88D radar located in Melbourne, FL, it is demonstrated that radar-based rainfall estimation using an adaptive RBF neural network is feasible. The results show that 73% of overnight updating for the RBF neural network can be completed within 2 h, and the estimation over an area of 100 km/spl times/100 km can be generated within the time frame (a few tens of seconds-150 s), which is much smaller than the average radar volume scan time.     

Determining Q of near-surface materials from Rayleigh waves

High-frequency (≥2 Hz) Rayleigh wave phase velocities can be inverted to shear (S)-wave velocities for a layered earth model up to 30 m below the ground surface in many settings. Given S-wave velocity (V_S), compressional (P)-wave velocity (V_P), and Rayleigh wave phase velocities, it is feasible to solve for P-wave quality factor Q_P and S-wave quality factor Q_S in a layered earth model by inverting Rayleigh wave attenuation coefficients. Model results demonstrate the plausibility of inverting Q_S from Rayleigh wave attenuation coefficients. Contributions to the Rayleigh wave attenuation coefficients from Q_P cannot be ignored when Vs/V_P reaches 0.45, which is not uncommon in near-surface settings. It is possible to invert Q_P from Rayleigh wave attenuation coefficients in some geological setting, a concept that differs from the common perception that Rayleigh wave attenuation coefficients are always far less sensitive to Q_P than to Q_S. Sixty-channel surface wave data were acquired in an Arizona desert. For a 10-layer model with a thickness of over 20 m, the data were first inverted to obtain S-wave velocities by the multichannel analysis of surface waves (MASW) method and then quality factors were determined by inverting attenuation coefficients.     

X线侧位片与高分辨率CT对鼻骨骨折的对比研究

目的　通过86例鼻骨骨折的鼻骨X线侧位片与高分辨率CT(HRCT）对比研究，确定HRCT检查对鼻骨骨折的诊断价值。材料与方祛　86例鼻外伤或/和He、面外伤的患者均进行了鼻骨X线侧位摄影、HRCT扫描检查，经集体讨论，由有经验的放射医师对全部影像资料进行分析并进行统计学处理。结果HRCT显示所有的86例鼻骨骨折，但在此86例骨折中X线平片只显示了35例阳性，包括15例鼻骨汇合部骨折，7例双侧鼻骨骨折，3例复合骨折(鼻骨汇合部及双侧鼻骨骨折)，l0例鼻区骨折。X线平片显示5l例为阴性。结论　对鼻骨骨折的诊断，HRCT明显优于鼻骨X线侧位片，HRCT扫描检查可提高X线隐性鼻骨骨折的诊断，并可明确鼻骨骨折的类型、范围和程度，为临床诊断和治疗提供可靠的依据。