Crystal perfection studies of single crystal superalloy turbine blades by X-Ray diffraction methods

In the paper the crystal structure of single crystal CMSX-4 blade casts, applied in high pressure turbine of aircraft engines was analyzed. The longitudinal section of blade, cast at withdrawal rate of 3 mm/min was used as a sample. During the conducted research, following X-ray diffraction methods were applied: EFG -scan, Auleytner X-ray topography and analysis of diffraction reflex profile (“rocking curve”). The authors determined crystal orientation in entire blade casts on the basis of set criterion concerning values of angle — deviation of [001] direction from the direction of cast withdrawal. Conclusions concerning the crystal structure quality of the blade were drawn based on results from three different research methods. Local changes in crystal orientation on the surface of blade cast, also areas with significant structure defect degree and the presence of internal stresses were characterized

Effect of creep on crystallographic orientation in single crystal superalloy

The creep-rupture tests were performed on a single crystal rods made of CMSX-4 superalloy obtained at withdrawal rates of 3 and 5 mm/min. After the rupture the microstructure and fracture surface were examined and correlated with X-ray crystal rotation measurements by the -scan method. The conclusions about the crystal lattice rotation during creep test were provided

Determination of crystal orientation by Ω-scan method in nickel-based single-crystal turbine blades

The article presents an assessment of the crystal perfection of single-crystal turbine blades based on the crystal orientation and lattice parameter distribution on their surface. Crystal orientation analysis was conducted by the X-ray diffraction method Ω-scan and the X-ray diffractometer provided by the EFG Company. The Ω-scan method was successfully used for evaluation of the crystal orientation and lattice parameters in semiconductors. A description of the Ω-scan method and an example of measurement of crystal orientation compared to the Laue and EBSD methods are presented.This work was supported by the National Science Centre Poland (NCN) under Grant No. Preludium-UMO-2016/21/N/ST8/00240

Relationship Between Anti-DFS70 Autoantibodies and Oxidative Stress

Background: The anti-DFS70 autoantibodies are one of the most commonly and widely described agent of unknown clinical significance, frequently detected in healthy individuals. It is not known whether the DFS70 autoantibodies are protective or pathogenic. One of the factors suspected of inducing the formation of anti-DFS70 antibodies is increased oxidative stress. We evaluated the coexistence of anti-DFS70 antibodies with selected markers of oxidative stress and investigated whether these antibodies could be considered as indirect markers of oxidative stress. Methods: The intensity of oxidative stress was measured in all samples via indices of free-radical damage to lipids and proteins such as total oxidant status (TOS), concentrations of lipid hydroperoxides (LPH), lipofuscin (LPS), and malondialdehyde (MDA). The parameters of the non-enzymatic antioxidant system, such as total antioxidant status (TAS) and uric acid concentration (UA), were also measured, as well as the activity of superoxide dismutase (SOD). Based on TOS and TAS values, the oxidative stress index (OSI) was calculated. All samples were also tested with indirect immunofluorescence assay (IFA) and 357 samples were selected for direct monospecific anti DFS70 enzyme-linked immunosorbent assay (ELISA) testing. Results: The anti-DFS70 antibodies were confirmed by ELISA test in 21.29% of samples. Compared with anti-DFS70 negative samples we observed 23% lower concentration of LPH (P =.038) and 11% lower concentration of UA (P =.005). TOS was 20% lower (P =.014). The activity of SOD was up to 5% higher (P =.037). The Pearson correlation showed weak negative correlation for LPH, UA, and TOS and a weak positive correlation for SOD activity. Conclusion: In samples positive for the anti-DFS70 antibody a decreased level of oxidative stress was observed, especially in the case of samples with a high antibody titer. Anti-DFS70 antibodies can be considered as an indirect marker of reduced oxidative stress or a marker indicating the recent intensification of antioxidant processes

Improving the usefulness and use of patient survey programs: National Health Service Interview Study

Background: A growing body of evidence suggests a concerning lag between collection of patient experience data and its application in service improvement. This study aims to identify what health care staff perceive to be the barriers and facilitators to using patient-reported feedback and showcase successful examples of doing so. Objective: This study aimed to apply a systems perspective to suggest policy improvements that could support efforts to use data on the frontlines. Methods: Qualitative interviews were conducted in eight National Health Service provider locations in the United Kingdom, which were selected based on National Inpatient Survey scores. Eighteen patient-experience leads were interviewed about using patient-reported feedback with relevant staff. Interviews were transcribed and underwent thematic analysis. Staff-identified barriers and facilitators to using patient experience feedback were obtained. Results: The most frequently cited barriers to using patient reported feedback pertained to interpreting results, understanding survey methodology, presentation of data in both national Care Quality Commission and contractor reports, inability to link data to other sources, and organizational structure. In terms of a wish list for improved practice, staff desired more intuitive survey methodologies, the ability to link patient experience data to other sources, and more examples of best practice in patient experience improvement. Three organizations also provided examples of how they successfully used feedback to improve care. Conclusions: Staff feedback provides a roadmap for policy makers to reconsider how data is collected and whether or not the national regulations on surveys and patient experience data are meeting the quality improvement needs of local organizations

Statystyka w wykrywaniu informacji szyfrowanej

Mostly when word encrypted occurs in an article text, another word decryption comes along. However not always knowledge about the plaintext is the most significant one. An example could be a network data analysis where only information, that cipher data were sent from one user to another or what was the amount of all cipher data in the observed path, is needed. Also before data may be even tried being decrypted, they must be somehow distinguished from non-encrypted messages. In this paper it will be shown, that using only simple Digital Data Processing, encrypted information can be detected with high probability. That knowledge can be very helpful in preventing cyberattacks, ensuring safety and detecting security breaches in local networks, or even fighting against software piracy in the Internet. Similar solutions are successfully used in steganalysis and network anomaly detections.Nowoczesna kryptografia wykorzystuje wyszukane i skomplikowane obliczeniowo przekształcenia matematyczno-logiczne w celu ukrycia ważnej informacji jawnej przez osobami niepowołanymi. Przeważająca większość z nich nadal odwołuje się do postawionego w roku 1949 przez Claude'a E. Shannona postulatu, że idealnie utajniona informacja charakteryzuje się tym, że żaden z pojawiających się w niej symboli nie jest bardziej prawdopodobny niż inne spośród używanego alfabetu znaków. Zgodnie z tą definicją dane idealnie zaszyfrowane w swej naturze przypominają dane losowe o rozkładzie równomiernym, czyli przypomina swoim rozkładem szum biały. Koncepcja detektora opiera się o algorytm analizujący podawane na wejściu dane pod względem ich podobieństwa do szumu białego. Wielkości odniesienia są bardzo dobrze znane, a ich ewentualne wyprowadzenie nie przysparza żadnych trudności. Wyznaczając w sposób doświadczalny granice tolerancji dla każdego z parametrów uzyskuje się w pełni działający algorytm, dokonujący w sposób zero-jedynkowy klasyfikacji na jawny/tajny. W grupie przedstawionych 14 Parametrów Statystycznych pojawiają się takie jak: energia, wartość średnia czy też momenty centralne. Na ich podstawie można stworzyć klasyfikator pierwszego poziomu. Efektywność poprawnego rozróżnienia danych przez klasyfikator pierwszego rzędu waha się w granicach od 80% do 90% (w zależności od użytej w algorytmie wielkości). W celu zwiększenia wykrywalności danych proponuje się, a następnie przedstawia, klasyfikator drugiego rzędu, bazujący na dwóch lub więcej, wzajemnie nieskorelowanych Parametrach Statystycznych. Rozwiązanie takie powoduje wzrost sprawności do około 95%. Zaproponowany w artykule algorytm może być wykorzystany na potrzeby kryptoanalizy, statystycznej analizy danych, analizy danych sieciowych. W artykule przedstawiona jest także koncepcja klasyfikatora trzeciego rzędu, wykorzystującego dodatkowo informacje o charakterze innym niż statystyczny, na potrzeby prawidłowej detekcji danych zaszyfrowanych

Effectiveness of statistic parameters in cipher data detection

Informacja szyfrowana, podobnie jak wszystkie inne typy danych, może zostać poddana analizie statystycznej. Wyznaczenie dla niej parametrów takich jak wartość średnia, wariancja czy też entropia nie nastręcza większych trudności. Wykorzystać do tego można nowoczesne narzędzia numeryczne jak np. MATLAB, Mathcad czy też Microsoft Exel. Pytanie, na które ma dać odpowiedź niniejsze opracowanie brzmi - "czy parametry te niosą ze sobą wiedzę, którą można wykorzystać w użyteczny sposób?" Przykładowym zastosowaniem może być np. określenie czy informacja jest zaszyfrowana (ang. cipher text), czy też jest ona jawna (ang. plain text).A cipher text, like any other data, can be analysed with use of parameters typical for statistics. Values such as the mean value, variance or entropy are easy to be calculated, especially if one can use numerical tools like e.g. MATLAB, Mathcad or simply Microsoft Exel. The question, to which this paper should give an answer is - "do those parameters provide any information that could be used in any useful way?" For example, the information, whether the analysed data is a cipher or plain text. The available publications about distinguishing the cipher from plain text use only methods typical for testing the randomness of cipher text and random number generator or immunity for cipher breaking. They are presented in the paper by the National Institute of Standards and Technology [1]. The other common method, used for distinguishing the data, is the analysis based on entropy [2]. Lack of published results about the efficiency of methods based on e.g. entropy, is additional motivation for this paper. (see Paragraph 1.) The proposed algorithms use parameters and transformations typical for Statistic and Signal Processing to classify the analysed data as cipher/plain. The authors assume that cipher data are very similar to random numbers due to Shannon's Perfect Secrecy theorem [3]. Six types of plain and cipher data (text, music, image, video, archives and others), seven types of cipher cores (3DES, AES, Blowfish, CAST - 128, RC4, Serpent, Twofish) and various length (1 B to 2323 B) data were examined and group of the so called Statistic Parameters was formed (see Table 1). Definitions of all of them (and a few more) are given by equations (1) to (12). The efficiency of Statistic Parameters after 1417 test samples is shown in Table 2. The most interesting results are also shown in Figs. 1 to 9. (see Paragraphs 2 - 4.) The results show that using simple values like e.g. energy one can built a data distinguisher of the efficiency equal to 90% and low numerical complexity. The lower bound for usability of this method was found to be 200 B. The upper bound was not found. The presented algorithm can be used for creating a network data analyser or cipher text detector. (see Paragraph 5.

Hardware detector of encrypted information transmitted in the TCP/IP networks

Artykuł prezentuje sposób realizacji, cechy charakterystyczne i zasadę działania urządzenia wykrywającego pakiety zawierające dane zaszyfrowane przesyłane w sieciach opartych o stos protokołów TCP/IP. Detektor zrealizowano w oparciu o system SPARTAN 3E Development Kit firmy Digilent [1]. Kluczowym elementem jest układ FPGA xc3s1600e firmy Xilinx [2]. W artykule przedstawiono schemat blokowy detektora, informacje o sprawności detekcji rozwiązania programowego oraz sprzętowego, zasobach logicznych zajętych przez układ.The paper describes how to realize a device which can detect encrypted data transfer in computer networks based on the TCP/IP protocols stack. Its features and principles of operation are given. The device is based on the Digilent's SPARTAN 3E Development Kit [1] whose key element is the Xilinx's xc3s1600e [2]. The available publications about distinguishing ciphertext from plaintext tell only that methods typical for randomness check of encrypting algorithms can be used [6]. Many alternative (in field of data distinguishing), interesting publications about steganography [7], computer worms and viruses detection can be easily found [3, 4]. Exemplary implementations of those in FPGA are not difficult to find, either [8]. Lack of publications in the field of encrypted message detection was partial motivation for this paper (Section 1). The presented algorithm of encrypted data detection is based on theorems from [9, 10]. It has advantages and disadvantages, which are discussed (Section 2). The detector (of so called 2nd order) chosen for implementation has good theoretical efficiency (Tab. 1). Its block diagram is shown in Fig. 1 (Section 3). The results of synthesis and implementation are given in Tab. 2, and its efficiency in Tab. 3. The functionality of all blocks of Fig. 1 is discussed (Sections 4 and 5). The efficiency of the implemented device is almost as good as the theoretical one. There are two main limitations - lower (100 B) and upper (1460 B) length of the Ethernet frame data field, and maximum frequency of device clock, which makes it unable (as for xc3s1600) to operate in Gigabit Ethernet networks (Section 6). The presented device can be used as a network data analyzer, a ciphertext detector and a network anomaly detector