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EN
The reconstruction of the osseous structures in the pelvic region after bone tumour resection is highly complex and challenging. Up to now the reconstruction of the pelvis defects by autologous or allogenous grafts (for instance the fibula transplants) are highly unsatisfied because of large shape differences. Therefore there is a huge demand for patient-specific and anatomically shaped implants. Our pelvis reconstruction planning approach is based on the statistical shape model. For generation of the statistical pelvis shape model a large data pool of CT datasets has been collected. The following CT data segmentation and surface processing methods delivered the required pelvis geometries. Via Procrustes analysis of the collected pelvis surfaces the parameterized pelvis shape mean model has been calculated and the principal component analysis (PCA) [3] applied for estimating the anatomically optimal graft or implant geometry. We will demonstrate on the clinical pelvis reconstruction case that the using of statistical shape models in the oncologic surgery planning is robust and very promising method.
2
Content available remote Wstęp do starożytnych teorii proporcji
EN
Some of the things that are nowadays taken for granted in mathematics, namely that line segments of a certain length can be well ordered, and "Euclidean" space is characterized by continuity and metricity, were problematic in antiquity. The main problem of ancient mathematics consisted in attempts to formulate anew a single mathematic theory after its disintegration into arithmetic and geometry caused by the discovery of incommensurability. Successive theories aimed at the metrization of geometric concepts and encompassed an ever increasing variety of mathematical objects. The paper proposes a new scheme of the development of ancient theories of proportion, which includes: I. Early theories of proportion (P_1 ), among which two phases of development and two further subtypes have been distinguished in phase two: P _1 a -early theorjes of numerical proportions and P _1 b -early theories of geometrical proportions. 2. Theories of numerical proportions motivated by studies of irrational magnitudes: the theory of Archytas (P _2) and the theory of Theaetetus (P _3). 3. Theories of purely geometrical proportions P _4 (mainly book IV of Euclid's Elements) 4. The first theory of proportion that included mixed proportions, i.e. numerjcal and geometrical proportions (P _5). 5. Eudoxus' theory ofproportions (P _6). The research of which the current paper presents the development of mathematics in a new light, and its results allow a reconstruction of the hermeneutic horizon for ancient mathematics.
EN
The article is treating of a new interpretation of ancient geometry (part I) and is willing to explain several mathematical and historical conceptions that were presented in Pappus' Comment on the X'h Book of 'Elements' of Euclid (part 11). Euclid's Elements were a kind of 'intuitive model', quite different from the contemporary one. Elements were divested of the 'infinitespace' notion. Reconstruction of the hermeneutic horizon of the ancient mathematics lets us explain structure and mathematics presented in the columns ofthe Xth book of Elements. The following subjects were handled: 1. reasons for elimination of the Euclid's ' infinite space' notion and substitutin.s it for Plato's Diad in ancient times, 2. basing geometry and searches over the incommensurable magnitudes on one distinguished line together with mathematical consequences, 3. differences in the way of thinking of ancient and contemporary mathematician. Scientific studies let qualify from the historical point of view the share in development of the incommensurable magnitudes theories presented by Theaetetus of Athens, Apollonius of Perga, Euclid and Eudoxus. In the article there is also presented a reconstruction of the mathematical contents of the lost Apollonius' treatise on incommensu- able magnitudes. A traditionally established pattern of the development of geometry, according to which Euclidean geometry used to extend as theory basing on relatively unalterable outfit of the fundamental intuition as, for instance, Euclid's infinite space, continuum intuitions and metric intuitions (what important, the first revolutionary change was a discovery of non -Euclidean geometry in the XIXth century) -cannot be sustained.
EN
Many medical diagnostics and treatment procedures in the oncology, cranio-maxillofacial surgery, radiotherapy and neurosurgery deal with volumetric as well as surface data. Tumor detection or generation of the virtual treatment scene involves using complementary data sets that are obtained from different sensors, for example MR and CT data, or by the same sensor at different epochs. The very need for registration arises from the fact that the complementary data sets are acquired by imaging devices using different spatial coordinate systems or/and the anatomically correct superposition of two data instances cannot be performed without locally applied elastic transformation. The volume or surface matching is therefore an essential task in these applications. From the mathematical point of view the data aligning problem is an optimization task, which can be solved by using deterministic or non-deterministic optimization algorithms. Depending on the data size and the complexity of required matching transformation the runtime behaviour of the registration methods can stretch out between real-time and many hours' computations. In this paper various applications of the same registration paradigm are presented and discussed. The wide spectrum of the medical applications shows the importance of the registration approach for the optimization of medical diagnostics and treatment.
EN
We present a methodology for navigation-aided surgical treatments in the reconstructive craniofacial surgery. Using the case of zygomatic bone repositioning after gunshot wound trauma the whole preoperative planning process and the intra-operative navigation oriented issues are explicitly described. We have focused our attention on the new navigation oriented aspects and procedures which facilitate and enhance the traditional treatment techniques. Many illustrations let better understand the complex technical dependencies between the main elements of this approach. The presented procedures permit more precise planning and performing of the surgical treatment, reducing intra-operative time and improving the post-operative outcome.
6
Content available Modeling of X-ray propagation in bone microstructure
EN
This paper presents some results concerning the analysis of X-ray propagation through biological structures. We introduce a physical model of the phenomenon and a numerical method based on this model for simulation of X-ray radiation propagation. The proposed method enables generation of radiological projections like those in the computed tomography or microtomography. We have focused our attention on the attenuation of X-ray radiation in bone tissue. Our computational model enables simulation of radiation propagation in the virtual specimen. The virtual bone microstructures used in our experiments are derived from the microtomography datasets of real bone specimens. The main advantage of our approach is that we can change the microstructure of the virtual sample in many ways by using the image processing methods. Results presented in this paper contain simulations of X-ray propagation for modified and unmodified trabecular microstructures as well as the visualization of the radiation intensity distribution for the simulated cases. With this new simulation technique, it is possible for example to analyze the propagation of X-ray radiation for different pathologic types of bone microstructure (e.g. virtually generated osteoporosis).
7
Content available remote Polska technologia odsiarczania zastosowana w kopalni gazu "Mełgiew"
PL
Zaangażowanie w rozwój metody odsiarczania paliw gazowych dostosowanej do potrzeb krajowych zaczyna wreszcie przynosić rezultaty: uruchomiona niedawno instalacja odsiarczania gazu ziemnego w KGZ "Mełgiew" koło Lublina jest już rozwiązaniem nie tylko oryginalnym w sensie technologicznym, ale i dojrzałym pod względem technicznym. Instalacja przeznaczona jest do odsiarczania ok. 300 m sześc./min gazu zanieczyszczonego nie tylko siarkowodorem, ale i, co rzadkie, organicznymi związkami siarki, takimi jak merkaptan metylowy, etylowy i wyższe. Produktem ubocznym procesu odsiarczania jest siarka elementarna odbierana w workach w postaci proszku o wilgotności ok. 30%. Instalacja nie produkuje ścieków, a zanieczyszczone powietrze technologiczne jest oczyszczane z organicznych związków siarki przed wypuszczeniem do atmosfery. Omówiono rozwiązania technologiczne węzłów całej instalacji: a więc również odgazolinowania i osuszania i porównano z dotychczas stosowanymi, oraz przedstawiono ciekawsze rozwiązania aparaturowe i propozycje producentów. Po raz pierwszy w górnictwie naftowym przy zagospodarowaniu złoża gazowego zastosowano układ skojarzony wytwarzania energii elektrycznej dla potrzeb własnych z zastosowaniem agregatów prądotwórczych z silnikiem gazowym, oraz wykorzystania ciepła z agregatu do celów technologicznych. Referat zilustrowano zdjęciami poszczególnych węzłów pracującej instalacji.
EN
Many years spent on development and implementation on local users' oriented gas treatment method has been effective in the end: the new redox type gas treating method used recently for gas field "Mełgiew" near Lublin in eastern Poland is not only radically different from most gas plant type methods but, because of many improvements based on "School of Hard Knocks" experienced for ten years on previous small installation, is now ready for broad application. The plant is treating 300 cum/min of natural gas contaminated not only by hydrogen sulfide, but also with organic sulfur compounds: methyl, thiol, ethyl thiol, and others. By products of the gas desulfurization process is: elemental sulfur in form of 30% water content pulver in bags, and electricity generated for use on site and for sale. Gas treatment plant generates no effluents, and spent air is treated before venting to atmosphere. Some remarks on other loops like gasoline removal and gas drying, as well as main equipment producers are mentioned.
EN
This paper reports on our experiences using datasets from the Visible Human Project in different biomedical applications. Introduced 1994 by the US National Library of Medicine the digitized multimodal anatomical datasets of the Visible Man have challenged the worldwide scientific community. A significant response to this challenge from several interdisciplinary research teams has emerged as a new area of research. This area requires close interaction and collaboration among anatomists, radiologists, computer scientists, mathematicians, engineers and physicians. The digitized volumetric images of the human body have been applied not only for the computer-aided exploration of the human gross anatomy, but also as structural input for the therapy planning and simulation systems. The importance of such virtual patient model is becoming increasingly recognized in modern medicine. To effectively use these specific datasets a sophisticated framework consisting of image processing, computer graphics and mathematical modelling methods is required. In this work various aspects of the developed framework are presented and discussed. Some preliminary results of our biomedical simulations are presented.
EN
This paper presents a methodology that addresses important issues concerned with the optimization of the misregistration measures in the volumetric medical data registration problem. Our registration framework uses robust simulated annealing method to handle multiple local minima of the cost function. Our efforts have been centred on obtaining a reliable, efficient and generally applicable method to solve such optimization problems. This has been accomplished through developing an adaptive cooling schedule for the simulated annealing method. The proposed method is very reliable for the estimation of the global minimum in the optimization of objective functions with highly differentiated search space landscapes. We present the detailed description of the method as well as discussion of its advantages and disadvantages.
EN
Registration is an important component of many medical data processing applications. Particularly significant is its role in the correlation of volumetric medical data aiming at generation of virtual patient-specific anatomical models. Such models enable optimization of various diagnostic and therapeutical procedures. The importance of the virtual patient models is becoming increasingly recognized in modern medicine. The advantages of using such biomedical virtual models are analogous to the advantages of real system behavior simulation in the engineering or material sciences. In this work some numerical issues associated with the registration problem and the visualization challenges arising in the context of virtual anatomical models have been presented and discussed.
EN
The alignment of volumetric datasets is an important problem in the processing of medical data. It is a prerequisite to numerous image based applications in diagnostic and therapeutic routines. In this paper, a new method is proposed for matching of 3D intramodality medical images. Our approach is based on some generalization of feature distance definition. Analogous to the standard surface matching, our algorithm uses also the chamfer distance like metric to define the quality of match function, however, the evaluation of the distance map is performed in a different way. The s-distance method is a step towards an automatic extraction of features, where each feature’s role in the registration process is weighted based on its relative statistical or spatial significance. As an alternative to the user-dependent non-automatic registration methods this approach offers a good assessment of similarity in the intramodality case. The elimination of less significant features in the registration process has resulted in a greatly improved efficiency over the voxel-based methods. Studying certain properties of the search space topography provides some insights into the performance of the proposed method as well as the standard registration algorithms in the rigid body registration problem.
EN
This paper presents a method for computer assisted selection of optimal donor sites for autologous osseous grafts in the craniofacial surgery. At the initial graft design stage the surgeon defines in the CT data set the shape of the bone segment to be reconstructed and in the donor region CT data set a set of constraints for the optimization task. This non-automatic step is followed by a fully automatic optimization stage, which delivers a set of sub-optimal and optimal donor sites for a given template. Such approach permits the surgeon to find the best site for harvesting the graft and enables an exact anatomical reconstruction of the osseous section.
13
Content available remote An automated osteotomy design for autologous bone grafts in craniofacial surgery
EN
In the treatment of craniofacial osseous defects it is frequently required that the surgeon has to graft bone to replace a missing or surgically removed segment. The reconstruction of this area poses a difficult challenge owing to the complexity of its bony structures as well as to its great importance for the chewing and speech ability. A common method of surgically reconstructing the craniofacial region involves using autologous grafts. By using the registration framework a novel surgery planning method has been developed. The method enables computer-aided selection of optimal donor sites for autologous bone grafts in the craniofacial surgery. The main advantage of the method is that after determination of the initial conditions and constraints it provides an automatic procedure to find the best fitting position. All generated solutions can be explored interactively on the computer display via an efficient graphical interface. Applying different similarity measures enables the surgeon to select the optimal donor site not only in terms of bone surface correlation but also according to the whole volumetric information contained in both data sets. This new approach permits more precise planning of the surgical procedure, reducing intraoperative time and improving the postoperative outcome.
PL
Wsród współczesnych technologii odsiarczania gazu ziemnego przydatnych dla niewielkich obiektów wyróżniają się korzystne metody "Redox", których produktem końcowym jest siarka elementarna. Spośród nich szczególnie szybko rozwijają się technologie wykorzystujące chelaty żelaza (Fe-EDTA) jako katalizator konwersji H2S do siarki. Artykuł prezentuje wyniki testowania i wdrożenia w O/SZGNiG Sanok krajowej odmiany chelatowej technologii odsiarczania opracowanej przez IGNiG Kraków, znanej pod nazwą IGNiG-Chelate.
EN
Among the contemporary natural gas desulfurization technological processes that are suitable for rather small-size plants, distinguished as advantageous are the "Redox" methods with elementary sulphur as the final product. Out of them, the technological processes that utilize iron chelates (Fe-EDTA) as a catalyzer of conversion of H2S to elemental sulphur undergo a particularly rapid development. The article presents the results of testing and implementation, in the O/SZGNiG Sanok, of a domestic modification of the chelate Desulfurization technology, known under the name of IGNiG-Chelate, developed by the Purification and Odorizing Unit of the Institute of Oil Mining & gas Engineering - Warsaw Branch /Zakład Technologii Oczyszczania i Nawadniania, Instytut Górnictwa Naftowego i Gazownictwa - Oddział w Warszawie/.
15
Content available remote Doświadczenia O/SGNiG Sanok w odsiarczaniu gazu ziemnego metodą IGNiG-Chelate
PL
Wśród współczesnych technologii odsiarczania gazu ziemnego przydatnych dla niewielkich obiektów wyróżniają się korzystnie metody "Redox", których produktem końcowym jest siarka elementarna. Spośród nich szczególnie szybko rozwijają się technologie wykorzystujące jako katalizator konwersji H2S do siarki chelaty żelaza (Fe-EDTA). Artykuł prezentuje wyniki testowania i wdrożenia w O/SZGNiG Sanok krajowej odmiany chelatowej technologii odsiarczania, znanej pod nazwą IGNiG-Chelate opracowanej przez Zakład Technologii Oczyszczania i Nawaniania Instytutu Górnictwa Naftowego i Gazownictwa - Oddział w Warszawie.
EN
Giving elementary sulfur as the final product, Redox methods have been found especially favourable to desulfurize natural gases in small plants. And among them the most promising are the processes where iron chelates are used as catalysts to convert H 2S into sulfur. The paper reports some results of tests on implementation of a Polish version of the technology, known as IGNiG-Chelate method. It has been developed by Department of Purification and Odorization Technologies in Oil and Gas Institute Subsidiary in Warsaw.
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