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101.
The paper presented assessment of sealed fire states in underground coal mines by so-called "fire characteristic", which graphically described tendencies of fire gas components - oxygen, nitrogen, carbon dioxide, carbon monoxide and hydrocarbons - in time. In order to mark gas components tendencies in time the authors applied the time series analysis. The case studied confirmed, that analysis of fire gas components tendencies in time and their correlation allow to elicit proper conclusions about fire state assessment. Assessment of fire states based on single value of fire indexes without considering their trends in time and correlation between trends of gas components would give wrong results. The suggested method can appropriately indicate fire states in a sealed area.  相似文献   
102.
CXCL16 is a chemotactic cytokine belonging to the α-chemokine subfamily. It plays a significant role in the progression of cancer, as well as the course of atherosclerosis, renal fibrosis, and non-alcoholic fatty liver disease (NAFLD). Since there has been no review paper discussing the importance of this chemokine in various diseases, we have collected all available knowledge about CXCL16 in this review. In the first part of the paper, we discuss background information about CXCL16 and its receptor, CXCR6. Next, we focus on the importance of CXCL16 in a variety of diseases, with an emphasis on cancer. We discuss the role of CXCL16 in tumor cell proliferation, migration, invasion, and metastasis. Next, we describe the role of CXCL16 in the tumor microenvironment, including involvement in angiogenesis, and its significance in tumor-associated cells (cancer associated fibroblasts (CAF), microglia, tumor-associated macrophages (TAM), tumor-associated neutrophils (TAN), mesenchymal stem cells (MSC), myeloid suppressor cells (MDSC), and regulatory T cells (Treg)). Finally, we focus on the antitumor properties of CXCL16, which are mainly caused by natural killer T (NKT) cells. At the end of the article, we summarize the importance of CXCL16 in cancer therapy.  相似文献   
103.
Carlina acaulis L. has a long tradition of use in folk medicine. The chemical composition of the roots and green parts of the plant is quite well known. There is the lowest amount of data on the cypsela (fruit) of this plant. In this study, the microscopic structures and the chemical composition of the cypsela were investigated. Preliminary cytochemical studies of the structure of the Carlina acaulis L. cypsela showed the presence of substantial amounts of protein and lipophilic substances. The chemical composition of the cypsela was investigated using spectrophotometry, gas chromatography with mass spectrometry, and high-performance liquid chromatography with spectrophotometric and fluorescence detection. The cypsela has been shown to be a rich source of macro- and microelements, vegetable oil (25%), α-tocopherol (approx. 2 g/kg of oil), protein (approx. 36% seed weight), and chlorogenic acids (approx. 22 g/kg seed weight). It also contains a complex set of volatile compounds. The C. acaulis cypsela is, therefore, a valuable source of nutrients and bioactive substances.  相似文献   
104.
ABSTRACT

Molecular dynamics simulations are carried out to study the evolution of stress during deposition of atoms on the (001) plane of an FCC crystal, using rectangular simulation box with xy periodic boundary conditions. The system consists of grains and boundaries. In the current study, we consider different values of the grain-to-grain distances and different relative sizes of deposited atoms. The structure was determined by the kinematical scattering theory. The main factors influencing the stress in thin film systems are creating of dislocation and changing the crystalline structure in grains. The deposited atoms can significantly contribute to the total stress. Depending on their size, atoms contribute compressive or tensile stresses to the total stress.

This paper is part of a Thematic Issue on The Crystallographic Aspects of Metallic Alloys.  相似文献   
105.
In the present work, the influence of Cr and Ca co-additives on the phase formation under conditions emulated the real sintering process of Cr4+:YAG ceramics is studied. The XRD analysis of the treated samples revealed the difference in formation rates of intermediate phases between the samples with and without the Cr2O3 additive. The formation of intermediate phases in the solid-state reaction between Y2O3 and Al2O3 is observed to shift toward higher temperatures (ie, toward the stage of fast shrinkage) if the mixture of Cr2O3 and CaO is added. The reason for such shift is the appearance of new intermediate, which contains Cr4+ ions in perovskite structure, as has been established by optical absorption and luminescent investigations. It is found that the Cr,Ca:YAG ceramics prepared by vacuum solid state reaction sintering at 1750°C, 10 hours possesses better optical transparency than Ca:YAG ceramics prepared under the same conditions.  相似文献   
106.
This paper presents the time-domain approach to the analysis of the convergence of continuous-time adaptive control and estimation algorithms. The time-domain definition of persistently exciting signals is introduced and the convergence of estimation algorithms is established in the cases of open-loop and closed-loop systems. An application of the persistency of excitation theory to the design of a globally stable adaptive pole-placement controller is given.  相似文献   
107.
The influence of the glow discharge in argon and oxygen mixture on the effectiveness of the surface-hardening treatment of titanium and its alloys, is presented in this paper. The high solubility of oxygen in the titanium matrix is the base of the discussed technology. Interstitially placed oxygen causes significant hardness increment as well as wear resistance.The rectangular flat specimens of Ti6Al4V alloy underwent the process of plasma thermal oxidation (TO) in atmosphere Ar+O2 which led to diffusion strengthening. The temperature of the process was 1223 K—lower than the higher temperature range of the recrystallization process. The experiments were carried out without plasma, with plasma presence during the whole process and the plasma presence only in diffusion stage. The substrates were examined with the use of scanning electron microscope. The chemical composition of formed oxides was determined. In addition to the X-ray analysis, the cross-section inspections as well as the hardness distribution in hardened layers assessment were also done.The main conclusion is that the plasma glow discharge presence during the whole process is not advantageous because the complex oxides that are difficult to dissolve in the matrix are formed. And although the surface hardness is the highest in this case, it is unfortunately connected with brittleness increase. The presence of plasma in diffusion stage is more preferable because it works “mechanically” on the oxides layer that is additionally thinner and causes the formation of thicker strengthened zone. However in both cases the use of plasma makes the process more effective than “typical” oxidation process.  相似文献   
108.
Recent developments in modeling stream of variation in multistage manufacturing system along with the urgent need for yield enhancement in the semiconductor industry has led to complex large scale simulation problems in design and performance prediction, thus challenging current Monte Carlo (MC) based simulation techniques. MC method prevails in statistical simulation approaches for multi-dimensional cases with general (i.e., non-Gaussian) distributions and/or complex response functions. A method is proposed based on number theory (NT-net) to reduce computing effort and the variability of MC's results in tolerance design and circuit performance simulation. The sampling strategy is improved by introducing NT-net that can provide better convergent rate over MC. The new method is presented and verified using several case studies, including analytical and industrial cases of a filter design and analyses of a four-bar mechanism. Results indicate a 90–95% reduction of computation effort with significant improvement in accuracy that can be achieved by the proposed technique.  相似文献   
109.

Supervision of repair and diagnostic works aimed at improving the safety of maintenance crews is one of the key objectives of the distributed INRED system. Working in a real industrial environment, the INRED system includes, among others, the so-called INRED-Workflow, which provides an infrastructure for process automation. Participants of the service processes, managed by the INRED-Workflow, are controlled at each stage of the performed service procedures, both by the system and other process participants, such as quality managers and technologists. All data collected from the service processes is stored in the System Knowledge Repository (SKR) for further processing by using advanced algorithms, and the so-called Smart Procedures merge services supplied by other INRED system modules. The applicability of workflow management systems in conjunction with image recognition and machine learning methods has not yet been thoroughly explored. The presented paper shows the innovative usage of such systems in the supervision of the repair and diagnostic works.

  相似文献   
110.
The article discusses our study of the problem of blurred image regions detection. Proposed are 21 features: 20 based on the discrete wavelet transform and one being a ratio based on a gray-level co-occurrence matrix. Described features are introduced in order to detect blurred segment regardless of the blur type such as background blur, motion blur, or out of focus. Moreover, proposed features are relatively easy to calculate and parallelize. Multilayer perceptron with a backpropagation algorithm is trained on mentioned features. Three approaches are introduced and tested: (1) with nonoverlapping fixed size windows, (2) with nonoverlapping recursively divided windows, and (3) with addition of a morphological closing operator.  相似文献   
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