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81.
In the present paper, the literature on the development of methods for histometric monitoring the quality of meats is reviewed. The value of specific techniques, statistical interpretation of results and the practicability of automation of histometric analysis are examined more closely. It is concluded from the study of the literature that histometric examination of meats allows an objective assessment of volume percentages of tissue components. When a distinct difference in contrast between various tissues is achieved by specific staining methods, developments in the field of image analysis systems will allow automation of the quantitative histological examination of meats.  相似文献   
82.
In this work we develop a new alternative to conventional maps for visualization of relatively short paths as they are frequently encountered in hotels, resorts or museums. Our approach is based on a warped rendering of a 3D model of the environment such that the visualized path appears to be straight even though it may contain several junctions. This has the advantage that the beholder of the image gains a realistic impression of the surroundings along the way which makes it easy to retrace the route in practice. We give an intuitive method for generation of such images and present results from user studies undertaken to evaluate the benefit of the warped images for orientation in unknown environments.  相似文献   
83.
传感器的基底为Al板电化学氧化成Al2O3绝缘层模板,上面真空溅射了叉指金电极,在电极之间旋涂微量多壁碳纳米管的水悬浊液,干燥后作为敏感膜.室温下测试传感器暴露在不同湿度的电阻变化,发现吸附了H2O后传感器的导电能力降低,且下降的幅度与被测湿度有良好的梯度关系.同时该多壁碳纳米管再经缩合剂EDC修饰后旋涂于电极上形成的敏感膜对湿度呈指数级变化.对它们的湿敏响应的机理进行了一些初步的探讨.  相似文献   
84.
One of the key problems in accelerometry based gait analyses is that it may not be possible to attach an accelerometer to the lower trunk so that its axes are perfectly aligned to the axes of the subject. In this paper we will present an algorithm that was designed to virtually align the axes of the accelerometer to the axes of the subject during walking sections. This algorithm is based on a physically reasonable approach and built for measurements in unsupervised settings, where the test persons are applying the sensors by themselves. For evaluation purposes we conducted a study with 6 healthy subjects and measured their gait with a manually aligned and a skewed accelerometer attached to the subject's lower trunk. After applying the algorithm the intra-axis correlation of both sensors was on average 0.89±0.1 with a mean absolute error of 0.05g. We concluded that the algorithm was able to adjust the skewed sensor node virtually to the coordinate system of the subject.  相似文献   
85.
基于WebGIS的城市供水管网系统的设计与实现   总被引:1,自引:0,他引:1  
介绍了基于WebGIS的城市供水管网信息系统的体系结构、功能组成以及供水管网建模技术.城市供水管网系统主要包括管网建模、查询统计、爆管事故分析、运行状态监控、漏损分析、系统维护等六个方面.城市供水管网建模是进行城市供水系统规划、设计、分析与优化调度的重要支撑技术,充分发挥WebGIS的分布式与可视化地理空间信息分析的优势,结合城市供水管网的管理需求,将WebGIS技术应用到城市供水管网的建模中.该系统可为城市供水部门的高效管理提供决策依据.  相似文献   
86.
Small changes to our ion source and gas ionization detector have significantly improved Cl measurement by reducing source memory and increasing interference rejection. Gas stripped low energy 30 MeV 36Cl5+ ions are still efficiently transported to the detector but 36S vs. 36Cl separation is improved by an order of magnitude. Accordingly 36Cl/Cl background is <10?15 before additional interference correction that is also newly automated. 35Cl? currents have increased to 30 μA and 36Cl/Cl inter-cathode repeatability is 3%.  相似文献   
87.
Benzene solutions of poly(phenylisopropenyl ketone) (PPIK), of copolymers of PIK and styrene and of phenyl-t-butyl ketone (pivalophenone) were irradiated with light flashes (duration 25 nsec) at wavelength 347 nm. The spectra observed at the end of the flash were attributed to the triplet state (T-T-spectra). A fraction of the triplets in the polymers was deactivated by T-T annihilation, as evidenced by lifetimes decreasing with increasing absorbed dose rate. Upon extrapolation to zero intensity the following triplet decay rate constants KT were obtained:
(1.0 ± 0.1) 107sec?(PPIK),
(8 ± 1) 106sec?1 (CPStPlK12), (6 ± 1) 106sec?1 (CPStPlK3.7)
(3 ± 1) 106sec?1 (CPStPlK1)
(2.5 ± 0.2) 106sec?1 (pivalophenone)
.In PPIK and pivalophenone the dominant chemical route of triplet deactivation is α-cleavage. The relatively high kT value found with PPIK is presumably due to next neighbour interaction. In copolymers with a high content of isolated PIK units type I processes (α-cleavage) become less probable due to weak next neighbour influence. Thus type II processes dominate in copolymers although being slower than type I processes in homo PPIK. The rate constant of the reaction of PIK triplets in homo PPIK with 2-propanol in benzene solution is (2.0 ± 0.2)106 l/mol sec, whereas pivalophenone triplets react almost 10 times slower with 2-propanol. The difference is assumed to be due to a rather strong interaction of 2-propanol with ground state as well as with excited pivalophenone.  相似文献   
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90.
Herein is a review of clear cell neoplasms of selected sites in the urinary tract and male reproductive system, including the kidney, the urinary bladder, testis, epididymis, and prostate. Clear cell cytoplasmic alteration in neoplasms at these sites is a relatively common light microscopic finding. Examples of such neoplasms with clear cell change include the clear cell type of renal cell carcinoma, clear cell adenocarcinoma of urethra and bladder, the classic type of seminoma, papillary cystadenoma of the epididymis, and well-differentiated adenocarcinoma of the prostate. Of importance, numerous non-neoplastic benign entities may also manifest cleared cytoplasm and therefore are presented in the differential in this review. Indeed, knowledge of the neoplastic and non-neoplastic entities displaying clear cell change at each anatomic site should enable the surgical pathologist to approach the differential diagnosis of these conditions in a more logical and rigorous fashion.  相似文献   
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