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51.
There are two methods applied for three-dimensional digital image correlation method to measure three-dimensional displacement. One is to measure the spatial coordinates of measuring points by analyzing the images. Then, the displacement vectors of these points can be calculated using the spatial coordinates of these points obtained at different stages. The other is to calibrate the parameters for individual measuring points locally. Then, the local displacements of these points can be measured directly. This study proposes a simple local three-dimensional displacement measurement method. Without any complicated distortion correction processes, this method can be used to measure small displacement in the three-dimensional space through a simple calibration process. A laboratory experiment and field experiment are carried out to prove the accuracy of this proposed method. Laboratory test errors of one-dimensional experiment are similar to the accuracy of the XYZ table; the error in Z-direction is only 0.0025% of the object distance. The measurement error of laboratory test is about 0.0033% of the object distance for local three-dimensional displacement measurement test. Test and analysis results of field test display that in-plane displacement error is only 0.12 mm, and the out-of-plane error is 1.1 mm for 20 m × 30 m measuring range. The out-of-plane error is only about 10 PPM of the object distance. These test and analysis results show that this proposed method can achieve very high accuracy under small displacement for both of laboratory and field tests. 相似文献
52.
53.
This report describes the clinicopathologic and immunohistochemical features of 14 cases of epithelioid trophoblastic tumor (ETT), a distinctive but rare gestational trophoblastic tumor. The patients with this neoplasm were in the reproductive age group and presented with abnormal vaginal bleeding. Although diagnosis was usually associated with a gestational event, the latter was sometimes remote. Two of the 14 patients presented with extrauterine ETT without evidence of prior gestational trophoblastic disease in the uterus. Serum human chorionic gonadotropin levels were elevated in eight of nine patients in whom this information was available. In the uterus, ETT presented as a discrete, hemorrhagic, solid and cystic lesion that was located either in the fundus, lower uterine segment, or endocervix. Microscopically, the tumor was composed of a relatively uniform population of mononucleate intermediate trophoblastic cells forming nests and solid masses. The cells resemble the trophoblastic cells in the chorion laeve, and we have therefore designated them "chorionic-type intermediate trophoblast." Typically, islands of trophoblastic cells were surrounded by extensive necrosis and were associated with a hyaline-like matrix creating a "geographic" pattern that is quite characteristic of this lesion. The mean mitotic count was two mitoses per 10 high-power fields, and the average Ki-67 nuclear labeling index was 18%. Immunohistochemically, all cases were diffusely positive for inhibin-alpha, cytokeratin (AE1/AE3), epithelial membrane antigen, E-cadherin, prolyl 4-hydroxylase, and epidermal growth factor receptor but were only focally immunoreactive for human placental lactogen, human chorionic gonadotropin, PlAP, and Mel-CAM. The monomorphic growth pattern of ETT resembles placental site trophoblastic tumor to a much greater degree than choriocarcinoma which is characterized by a dimorphic population of trophoblast. In contrast to placental site trophoblastic tumor, the cells of ETT are smaller and display less nuclear pleomorphism. In addition, ETT grows in a nodular fashion compared with the infiltrative pattern of placental site trophoblastic tumor. In some of the cases, the trophoblastic cells in ETT replaced the endocervical surface epithelium, giving the appearance that the tumor was derived from the cervix. Moreover, because the associated hyaline-like material in ETT resembles keratin, the tumor can be misinterpreted as a keratinizing squamous cell carcinoma of the cervix. Ten patients underwent total hysterectomy and two had an endometrial curettage only. The two patients who presented with extrauterine ETT underwent small bowel resection and lung resection. Two of 12 patients with ETT in the uterus developed metastasis in the lungs and bone. One of these patients is alive with disease at 43 months and one patient was lost to follow-up after 2 months. One of the two patients who had extrauterine disease died of widespread tumor 36 months after diagnosis. The remainder of the patients are alive and well from 1 to 120 months. In summary, ETT is a rare trophoblastic tumor that simulates carcinoma and can behave in a malignant fashion. It appears to be less aggressive than choriocarcinoma, more closely resembling the behavior of placental site trophoblastic tumor. Based on the morphologic and immunohistochemical features, it appears that ETT develops from neoplastic transformation of chorionic-type intermediate trophoblast. 相似文献
54.
Abstract— Owing to the fast developments of computer networks and color imaging technologies, there is a tendency towards remote proofing in the printing or textile industries. More cases such as cross‐display color matching will occur in the future information society. The problems of color mismatching we usually find in cross‐display devices have been widely discussed today. In this paper, to achieve equivalent color matching between a sRGB monitor and an Adobe RGB monitor, the spatial gamut mapping algorithm (SGMA), which introduces sigmoidal tone mapping, multi‐mapping paths, and unsharp mask (USM) operation into a sRGB color‐management system, is proposed. According to the designs of USM locations, this proposed SGMA can be further developed into pre‐USM, post‐USM, and double‐USM types. Besides, two critical image characteristics, edge map and color histogram, are investigated to establish the relationship between image content and SGMA. The psychophysical experimental results show that double‐USM SGMA obtains better color matching than the other spatial types. 相似文献
55.
Since a large variety of digital games have been used in many fields for educational purposes, their real functions in learning have caught much attention as well. This study first defines learning characteristics of problem-solving digital games and their corresponding cognitive levels, then designs and develops a problem-solving game in accordance to the criteria. Tasks in the game context are inter-related to each other so that players need to critically and creatively think about problem solutions. Learners’ task analyses are performed to observe four elementary learners’ gaming paths, behaviors and cognitive activities, individually and collaboratively. System documentation, video recording, researcher observation, and interviews are conducted to analyze learners’ learning strategies and their cognitive performance during the gaming process. 相似文献
56.
Wen-Bin Lin Huann-Keng Chiang Kuang-Rong Shih Chien-An Chen 《Artificial Life and Robotics》2010,15(4):473-477
This article proposes the PC-based LabVIEW as the software to develop the algorithm of the robust complex extended Kalman
filter (RCEKF) to detect the parameters of the voltage signal in power systems. The hardware used is a sample-and-hold card
and a data acquisition (DAQ) card to extract the data from an outside system to the PC, and the program will compute the amplitude,
frequency, and phase of the voltage signal with RCEKF. To validate the performance of RCEKF, the voltage signal from a function
generator was applied to check the feasibility of the algorithm. This application was also used in the Taiwan Power Company
(TPC) secondary substation in Sijhou, Taiwan. 相似文献
57.
Han M. Shih 《Computers & Industrial Engineering》2011,61(3):608-628
In geometry, two configurations are called similar if they can be brought to a complete match by rigid motions and dilations. In the simplest case, product designs X and Y have the same dimensionality and same number of points which can be brought into a one to one correspondence by substantive considerations. Under orthogonal transformations, product design Y can only be rotated and reflected in order to approximate product design X. As for the “as close as possible” or “relatively close” criterion, a reasonable definition would be to measure the distances between corresponding points, square these values, and add them to obtain the sum-of-squares criterion L. In this paper, a product structure (BOM)-based product similarity measures using orthogonal procrustes approach is proposed. A structural product is first transformed into bill of materials (BOM), the structural similarity measurement between a product query and target product is calculated and evaluated using orthogonal procrustes approach. The results show that the proposed product structure similarity measure method can help companies find desired product information based on BOM feature. 相似文献
58.
We have investigated real-time, label-free, in-situ detection of human epidermal growth factor receptor 2 (Her2) in diluted serum using the first longitudinal extension mode of a lead zirconate-lead titanate (PZT)/glass piezoelectric microcantilever sensor (PEMS) with H3 single-chain variable fragment (scFv) immobilized on the 3-mercaptopropyltrimethoxysilane (MPS) insulation layer of the PEMS surface. We showed that with the longitudinal extension mode, the PZT/glass PEMS consisting of a 1 mm long and 127 μm thick PZT layer bonded with a 75 μm thick glass layer with a 1.8 mm long glass tip could detect Her2 at a concentration of 6-60 ng/ml (or 0.06-0.6 nM) in diluted human serum, about 100 times lower than the concentration limit obtained using the lower-frequency flexural mode of a similar PZT/glass PEMS. We further showed that with the longitudinal mode, the PZT/glass PEMS determined the equilibrium H3-Her2 dissociation constant K(d) to be 3.3±0.3 × 10(-8) M consistent with the value, 3.2±0.28 ×10(-8) M deduced by the surface plasmon resonance method (BIAcore). 相似文献
59.
Feehrer John Rotker Paul Shih Milton Gingras Paul Yakutis Peter Phillips Stephen Heath John 《Micro, IEEE》2009,29(4):36-47
CoHub, a coherency hub ASIC, provides a cost-effective way to extend a glueless two-node chip-multithreading system to a four-node system without changes to the processor. The four-node, 256-thread system achieves near-linear scaling of performance with thread count on transaction-processing workloads. Time-to-market pressure, 800-MHz operation, and a six-stage pipeline were among the constraints that shaped CoHub's design. 相似文献
60.
Remote user authentication scheme is a procedure which allows a server to authenticate a remote user through insecure channel. Recently, Yoon, Ryu and Yoo made an enhancement based on Ku–Chen’s remote user authentication scheme by using smart cards. The scheme has the merits of providing mutual authentication, no verification table, freely choosing password, involving only few hashing operations and parallel session attack resistance. In this paper, we point out security flaws of Yoon–Ryu–Yoo’s protocols against masquerading attack, off-line password guessing attacks and parallel session attack. An improvement to enhance Yoon–Ryu–Yoo’s security scheme is proposed. 相似文献