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71.
Jasmine Chang Ian R. Porter Marnin A. Forman Natalya Shcherban Parminder S. Basran 《Veterinary radiology & ultrasound》2023,64(1):131-139
Measurements of intestinal wall thicknesses from ultrasound imaging (US) are routinely used to support diagnoses of intestinal disorders in cats, however published studies describing observer agreement are currently lacking. The aim of this retrospective, observer agreement study was to quantify inter- and intraobserver repeatability and agreement in the measurement of intestinal wall layer thicknesses and the segmentation of transverse sections of small intestines in US images of 20 cats. Intestinal wall layer thickness measurements of the mucosa, submucosa, muscularis, serosa layer, and total thickness of these layers were performed on five cats with small cell epitheliotropic lymphoma, five with inflammatory bowel disease, and 10 with other conditions. Thickness measurements and the segmentation encompassing the serosa layer were obtained from five observers four times non-sequentially. The average standard deviation in thickness measurements (95% confidence interval) in the mucosa, submucosa, muscularis, serosa, and total thickness were 0.35 (0.07–0.95), 0.24 (0.07-0.52), 0.22 (0.06-0.49), 0.20 (0.05-0.49), and 0.57 (0.11-1.60) mm, respectively. The average intraclass correlation coefficients, which estimates the degree of consistency in thickness measurements and segmentation areas for each observer, ranged from 0.355 to 0.870 and 0.850 to 0.993, respectively. The interclass correlation coefficient, which estimates the degree of consistency when measuring a thickness or segmentation area over all observers ranged from 0.115 to 0.753, and 0.811 to 0.902, respectively. The overall average Dice Coefficient, which estimates the extent of overlap of the segmentations for all observers was 0.957 (0.933 to 0.972). Our results suggest segmentations of small intestines have a higher interobserver agreement than measurements of intestinal wall thicknesses. 相似文献
72.
The mechanism of MIPv4 regional registration and the low latency handoff protocols are introduced. Ways and procedure of pre-registration handoff and post-registration handoff are discussed also. The authors analyze the performance of the low latency handoff protocols combined with low latency handoffs over a wireless access based on IEEE 802. 11 standard in a tree-like network topology. The performance of pre-registration and post-registration scheme is given by simulation. 相似文献
73.
74.
Considering the character of slope resistant engineering invest benefit, in line with security and economy balmaced, combining initial investment and anticipated hazard loss, disaster resistant engineering should be satisfied with the criterion of minimum cost. Decision tree model is adopted as analyzing means, and risk decision-making of slope design is carried out. Project input-output radio adopting dynamic analysis can reflect project investment benefit more accurately. At last this paper analyzes some questions in process of slope resistant engineering with benefits enumerate. 相似文献
75.
The influenfial factors of stratification plane to smooth blasting are studied according to the ti eory of smooth blasting and the anslysis of static stress. The results show that the angle p between the maximum principal plane and the rertical line of stratification plane has some influence on the fracture of rock masses. 相似文献
76.
This article puts forward a 3 Layers Model for the communication between embedded system and PC. It is based on the speciality of them and the TCP/IP model. The model defines the communicate process of embedded system to be three layers: Transport Layer, Control Layer and Application Layer. Each layer serves for its higher-up. It can keep the efficiency and credibility of the communicate process and the authors prove and analyse that in the article. the concept of the model is also suitable for Bluetooth, IrDA and other kinds of communication about embedded system. 相似文献
77.
Chen Qigao Feng Ya 《保鲜与加工》1993,(1)
This paper analyses the thermal moist characteristics of the hull layer beside an air layer at lower temperature in an envelope for a cold storage and presents a new method of waterproof by air layer. With test data from engineering practice, the theory on the barrier of self moisture proof at the surface sublayer of the hull layer in an attic on a cold storage is proven. The dried zone about three phase point is confirmed. It is a new knowledge for thermophysics on thermal design of a cold storage with an optimum thermal performance. 相似文献
78.
针对国内汽车企业不具备整车齐全的三维CAD模型的实际情况,提出一种基于动态装配图热点和产品结构树结点双向驱动的备件数据可视化管理方案,在Delphi开发平台上将Action Script技术和ActiveX技术集成到可视化备件管理系统中。详细阐述了图热点驱动和树结点驱动的程序实现流程.给出了动态装配图、装配结构树和界面数据窗三者之间的联动关系,实现两种驱动的等效性。为了便于用递归算法遍历结构树,对复杂网状结构的零部件从属依赖关系进行规范化处理.使之成为树形结构。采用约束递归迭代,对一次性加载零部件的层数和范围进行约束,用统一的虚拟临时结点代替当前非叶子结点的子结点,实现整车装配关系结构树构造过程的优化。 相似文献
79.
80.
Three trickle irrigation schedules, two of which were scheduled according to soil water potential ( soil) (tensiometer method) and daily stem contraction (DSC) (dendrometer method) respectively and the other one was a schedule of restricted water supply, were applied to a mature peach orchard.The annual water application based on soil was greater than that based on DSC. However, tree growth, fruit size and leaf water potential (leaf) on the trees in the dendrometer scheduling plot did not differ from those in the tensiometer scheduling plot while the premature fruit drop and fruit bud initiation were greatly different. The restricted water supply treatment limited significantly both tree and fruit growth. In addition, the lower leaf was observed on the trees in this plot.Further study shows that use of the dendrometer method for scheduling irrigation satisfies the water needs of the plant and that the tensiometer method is less accurate.Abbreviations leaf
leaf water potential
- soil
soil water potential
- DSC
daily stem contraction
- LVDT
linear variable displacement transducer
- PET
potential evapotranspiration 相似文献