scholarly journals Automatic Registration and Error Detection of Multiple Slices Using Landmarks

2001 ◽  
Vol 23 (3-4) ◽  
pp. 159-165
Author(s):  
Hans Frimmel ◽  
Lars Egevad ◽  
Christer Busch ◽  
Ewert Bengtsson

Objectives. When analysing the 3D structure of tissue, serial sectioning and staining of the resulting slices is sometimes the preferred option. This leads to severe registration problems. In this paper, a method for automatic registration and error detection of slices using landmark needles has been developed. A cost function takes some parameters from the current state of the problem to be solved as input and gives a quality of the current solution as output. The cost function used in this paper, is based on a model of the slices and the landmark needles. The method has been used to register slices of prostates in order to create 3D computer models. Manual registration of the same prostates has been undertaken and compared with the results from the algorithm. Methods. Prostates from sixteen men who underwent radical prostatectomy were formalin fixed with landmark needles, sliced and the slices were computer reconstructed. The cost function takes rotation and translation for each prostate slice, as well as slope and offset for each landmark needle as input. The current quality of fit of the model, using the input parameters given, is returned. The function takes the built‐in instability of the model into account. The method uses a standard algorithm to optimize the prostate slice positions. To verify the result, s standard method in statistics was used. Results. The methods were evaluated for 16 prostates. When testing blindly, a physician could not determine whether the registration shown to him were created by the automated method described in this paper, or manually by an expert, except in one out of 16 cases. Visual inspection and analysis of the outlier confirmed that the input data had been deformed. The automatic detection of erroneous slices marked a few slices, including the outlier, as suspicious. Conclusions. The model based registration performs better than traditional simple slice‐wise registration. In the case of prostate slice registration, other aspects, such as the physical slicing method used, may be more important to the final result than the selection of registration method to use.

Author(s):  
Yuan-Shyi P. Chiu ◽  
Jian-Hua Lian ◽  
Victoria Chiu ◽  
Yunsen Wang ◽  
Hsiao-Chun Wu

Manufacturing firms operating in today’s competitive global markets must continuously find the appropriate manufacturing scheme and strategies to effectively meet customer needs for various types of quality of merchandise under the constraints of short order lead-time and limited in-house capacity. Inspired by the offering of a decision-making model to aid smooth manufacturers’ operations, this study builds an analytical model to expose the influence of the outsourcing of common parts, postponement policies, overtime options, and random scrapped items on the optimal replenishment decision and various crucial system performance indices of the multiproduct problem. A two-stage fabrication scheme is presented to handle the products’ commonality and the uptime-reduced strategies to satisfy the short amount of time before the due dates of customers’ orders. A screening process helps identify and remove faulty items to ensure the finished lot’s anticipated quality. Mathematical derivation assists us in finding the manufacturing relevant total cost function. The differential calculus helps optimize the cost function and determine the optimal stock-replenishing rotation cycle policy. Lastly, a simulated numerical illustration helps validate our research result’s applicability and demonstrate the model’s capability to disclose the crucial managerial insights and facilitate manufacturing-relevant decision making.


2019 ◽  
Vol 97 ◽  
pp. 03016
Author(s):  
Serafima Sokova ◽  
Vladimir Kalinin

the main issue of the study is the problem of improving the efficiency of the housing sector. The current state system does not ensure the proper efficiency of the housing stock, which is increasingly manifested in the growing gap between the cost of operation of apartment buildings, aimed at ensuring the quality of their functioning and the real state of this quality. In recent years, numerous regulatory documents have been adopted to ensure the normal maintenance of buildings, but a comprehensive understanding of the relationship of various activities with technical and economic solutions, in most cases, has an empirical nature, not confirmed by a strict analytical justification. The purpose of the study is a systematic integrated approach to solving problems to improve the efficiency of maintenance of housing using the proposed mathematical apparatus, which allows you to objectively, fully and accurately assess the relationship of economic and technical indicators. All total socially significant economic indicators of operational measures can be the basis of legislative regulation in the industry. Conclusions: criteria for assessing the effective and safe operation of buildings, optimal for residents of apartment buildings and management companies serving these houses.


2019 ◽  
Vol 12 (5) ◽  
pp. 2967-2977 ◽  
Author(s):  
Simone Ceccherini ◽  
Nicola Zoppetti ◽  
Bruno Carli ◽  
Ugo Cortesi ◽  
Samuele Del Bianco ◽  
...  

Abstract. When the complete data fusion method is used to fuse inconsistent measurements, it is necessary to add to the measurement covariance matrix of each fusing profile a covariance matrix that takes into account the inconsistencies. A realistic estimate of these inconsistency covariance matrices is required for effectual fused products. We evaluate the possibility of assisting the estimate of the inconsistency covariance matrices using the value of the cost function minimized in the complete data fusion. The analytical expressions of expected value and variance of the cost function are derived. Modelling the inconsistency covariance matrix with one parameter, we determine the value of the parameter that makes the reduced cost function equal to its expected value and use the variance to assign an error to this determination. The quality of the inconsistency covariance matrix determined in this way is tested for simulated measurements of ozone profiles obtained in the thermal infrared in the framework of the Sentinel-4 mission of the Copernicus programme. As expected, the method requires sufficient statistics and poor results are obtained when a small number of profiles are being fused together, but very good results are obtained when the fusion involves a large number of profiles.


2019 ◽  
Author(s):  
Simone Ceccherini ◽  
Nicola Zoppetti ◽  
Bruno Carli ◽  
Ugo Cortesi ◽  
Samuele Del Bianco ◽  
...  

Abstract. When the complete data fusion method is used to fuse inconsistent measurements, it is necessary to add to the measurement covariance matrix of each fusing profile a covariance matrix that takes into account the inconsistencies. A realistic estimate of these inconsistency covariance matrices is required for effectual fused products. We evaluate the possibility of assisting the estimate of the inconsistency covariance matrices using the value of the cost function minimized in the complete data fusion. The analytical expressions of expected value and variance of the cost function are derived. Modelling the inconsistency covariance matrix with one parameter, we determine the value of the parameter that makes the reduced cost function equal to its expected value and use the variance to assign an error to this determination. The quality of the inconsistency covariance matrix determined in this way is tested for simulated measurements of ozone profiles obtained in the thermal infrared in the framework of the Sentinel 4 mission of the Copernicus programme. As expected, the method requires a sufficient statistics and poor results are obtained when a small numbers of profiles are being fused together, but very good results are obtained when the fusion involves a large number of profiles.


2020 ◽  
Vol 39 (8) ◽  
pp. 983-1001
Author(s):  
Takayuki Osa

Existing motion planning methods often have two drawbacks: (1) goal configurations need to be specified by a user, and (2) only a single solution is generated under a given condition. In practice, multiple possible goal configurations exist to achieve a task. Although the choice of the goal configuration significantly affects the quality of the resulting trajectory, it is not trivial for a user to specify the optimal goal configuration. In addition, the objective function used in the trajectory optimization is often non-convex, and it can have multiple solutions that achieve comparable costs. In this study, we propose a framework that determines multiple trajectories that correspond to the different modes of the cost function. We reduce the problem of identifying the modes of the cost function to that of estimating the density induced by a distribution based on the cost function. The proposed framework enables users to select a preferable solution from multiple candidate trajectories, thereby making it easier to tune the cost function and obtain a satisfactory solution. We evaluated our proposed method with motion planning tasks in 2D and 3D space. Our experiments show that the proposed algorithm is capable of determining multiple solutions for those tasks.


2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Matthias Hoffmann ◽  
Christopher Kowalewski ◽  
Andreas Maier ◽  
Klaus Kurzidim ◽  
Norbert Strobel ◽  
...  

For augmented fluoroscopy during cardiac ablation, a preoperatively acquired 3D model of a patient’s left atrium (LA) can be registered to X-ray images recorded during a contrast agent (CA) injection. An automatic registration method that works also for small amounts of CA is desired. We propose two similarity measures: The first focuses on edges of the patient anatomy. The second computes a contrast agent distribution estimate (CADE) inside the 3D model and rates its consistency with the CA as seen in biplane fluoroscopic images. Moreover, temporal filtering on the obtained registration results of a sequence is applied using a Markov chain framework. Evaluation was performed on 11 well-contrasted clinical angiographic sequences and 10 additional sequences with less CA. For well-contrasted sequences, the error for all 73 frames was 7.9±6.3 mm and it dropped to 4.6±4.0 mm when registering to an automatically selected, well enhanced frame in each sequence. Temporal filtering reduced the error for all frames from 7.9±6.3 mm to 5.7±4.6 mm. The error was typically higher if less CA was used. A combination of both similarity measures outperforms a previously proposed similarity measure. The mean accuracy for well contrasted sequences is in the range of other proposed manual registration methods.


Author(s):  
YANLI WAN ◽  
ZHEN TANG ◽  
ZHENJIANG MIAO ◽  
BO LI

Image composition is a very important technique in computer generated imagery. Besides some factors such as contrast, texture and noise that affect the quality of the composition, color harmony between fore- and background is also an important factor that would affect the quality of the composition. However, in the previous image composition techniques, color harmony between fore- and background is seldom considered. In this paper, an optimization method is proposed to deal with the color harmonization problem that used in image composition. A cost function is derived from the local smoothness of the hue values, and the image is harmonized by minimizing the cost function. A new matching cost function is proposed to select the best matching harmonic schemes. Our approach overcomes several shortcomings of the existing color harmonization methods. We validate the performance of our method and demonstrate its effectiveness with a variety of experiments.


10.6036/9762 ◽  
2021 ◽  
Vol 96 (5) ◽  
pp. 498-504
Author(s):  
JUAN LUIS TERRADEZ MARCO ◽  
ANTONIO HOSPITALER PEREZ ◽  
VICENTE ALBERO GABARDA

This paper proposal the optimization of a foundation for rotative machine under dynamic loads in transient and permanent working mode. The foundation depends on fix parameters and 37 variables. Functional constraints are defined for the foundation. A cost function depending on the variables is defined to be minimized to find the optimal. From all the possible solutions, only are selected the ones that validate the constrains and minimize the cost function. The search of the optimal solution is made with an algorithm of random search by “neighbouring of one point” called Last Acceptance Hill Climbing(LAHC). It is an algorithm of the type called “Adaptative Memory Programming” (AMP) that accepts worse solutions to get the local minimum and learns of the results of the search. The algorithm only depends on the length of the comparison vector and the stop criteria. 350 experiences were made with different length of the comparison vector. It was analysed the quality of the optimal solutions got it with each length of the vector. Quality of the set of solutions was compared fitting them to a 3 parameters Weibull distribution.


2012 ◽  
Vol 239-240 ◽  
pp. 990-993
Author(s):  
Xiao Ping Ren ◽  
Zhi Chao Xue ◽  
Ke Zhao

Bullet mark comparison is one of the key techniques in the discovery of evidences. A bullet mark comparison method was presented in this paper. First the bullet marks data are gathered according to generally used equipment. There are many coarse data cannot be used in matching process, so a preprocessing on the raw data is need. A statistics modeling is set up to construct a cost function, which can be used to evaluation choose of error until the cost function get minimum value. Experiment showed this comparison method can solve comparison problems of bullet mark.


Sign in / Sign up

Export Citation Format

Share Document