Two-run RAM march testing with address decimation

Conventional march memory tests have high fault coverage, especially for simple faults like stack-at fault (SAF), transition fault (TF) or coupling fault (CF). The same-time standard march tests, which are based on only one run, are becoming insufficient for complex faults like pattern-sensitive faults (PSFs). To increase fault coverage, the multi-run transparent march test algorithms have been used. This solution is especially suitable for built-in self-test (BIST) implementation. The transparent BIST approach presents the incomparable advantage of preserving the content of the random access memory (RAM) after testing. We do not need to save the memory content before the test session or to restore it at the end of the session. Therefore, these techniques are widely used in critical applications (medical electronics, railway control, avionics, telecommunications, etc.) for periodic testing in the field. Unfortunately, in many cases, there is very limited time for such test sessions. Taking into account the above limitations, we focus on short, two-run march test procedures based on counter address sequences. The advantage of this paper is that it defines requirements that must be taken into account in the address sequence selection process and presents a deeply analytical investigation of the optimal address decimation parameter. From the experiments we can conclude that the fault coverage of the test sessions generated according to the described method is higher than in the case of pseudorandom address sequences. Moreover, the benefit of this solution seems to be low hardware overhead in implementation of an address generator

Optimal controlled random tests

Controlled random tests, methods of their generation, main criteria used for their synthesis, such as the Hamming distance and the Euclidean distance, as well as their application to the testing of both hardware and software systems are discussed. Available evidences suggest that high computational complexity is one of the main drawbacks of these methods. Therefore we propose a technique to overcome this problem. In the paper we propose the algorithm for optimal controlled random tests generation. Both experimental and analytical investigation clearly show the high efficiency of proposed solution especially for the multi-run tests with small number of iterations. The given tests can be applied for hardware and software testing but it seems they may be particularly interesting from the perspective of the effective detection of pattern sensitive faults in RAMs

Methods of synthesis of controlled random tests

Controlled random tests, methods of their generation, main criteria used for their synthesis, such as the Hamming distance and the Euclidean distance, as well as their application to the testing of both hardware and software systems are discussed. Available evidences suggest that high computational complexity is one of the main drawbacks of these methods. Therefore we propose a technique to overcome this problem. A method for synthesizing multiple controlled random tests based on the use of the initial random test and addition operation has been proposed. The resulting multiple tests can be interpreted as a single controlled random test. The complexity of its construction is significantly lower than the complexity of the construction of classical random tests. Examples of generated tests as well as estimates of their effectiveness compared to other solutions have been presented in experimental studies

Generowanie wieloprzebiegowych kontrolowanych testów losowych

Controlled Random Tests and methods for their generation have been analyzed and investigated. The similarities of all known controlled random testing approaches are shown. The new method and algorithm for Multiple Controlled Random Tests have been proposed and analyzed

Лексическое наполнение современных газет российских немцев как реализация этнической функции языка

The purpose of our study was to determine the expression of the pro-apoptotic BAX protein in relation to the mutational status of BAX and p53 (as transcriptional activator of the BAX gene) in benign and malignant thyroid tissue. In 47 patients with thyroid tumours (14 follicular and 3 papillary carcinomas, 14 adenomas and 16 goitres), the DNA was screened for mutations of BAX (exon 1-6) and p53 (exon 5-8) by single-strand conformation polymorphism polymerase chain reaction (SSCP-PCR). Furthermore, the protein expression of BAX, p53 and p21 (which is also increased transcriptionally by p53) was investigated by immunohistochemistry. Surprisingly, we observed elevated BAX levels in patients with thyroid carcinomas compared with patients with adenomas (unpaired t-test: p<0.05) or with goitres (p<0.02). This is in clear contrast to other carcinomas where BAX is frequently inactivated which correlates to a poor prognosis (Sturm et al., 1999). There were no significant differences of the BAX levels between goitres or the adenomas. In the SSCP-PCR analysis, no BAX mutations were detectable. P53 mutation analysis by SSCP-PCR did not reveal any functional p53 mutations in the patients with carcinomas, adenomas or goitres. Nevertheless, patients with carcinomas showed an overexpression (preferentially cytoplasmic) of p53 protein compared with patients with benign tumours (p<0.05). The absence of p53 mutations suggests that the overexpressed p53 is wild type. This is in line with the expression profile of BAX and p21, which showed a higher protein expression in these p53 positive tumours (p<0.05 in the carcinomas compared with the non-malignant lesions). Consequently, the overexpressed p53 might be a correlate for dysregulation without loss of function. This, in turn, might be a reason for the good outcome of some patients with thyroid cancer

Universal Address Sequence Generator for Memory Built-in Self-test

This paper presents the universal ad-dress sequence generator (UASG) for memorybuilt-in-self-test. The studies are based on the proposed universal method for generating address se-quences with the desired properties for multirun march memory tests. As a mathematical model, a modification of the recursive relation for quasi-random sequence generation is used. For this model, a structural diagram of the hardware implementation is given, of which the basis is a storage device for storing so-called direction numbers of the generation matrix. The form of the generation matrix determines the basic properties of the generated ad-dress sequences. The proposed UASG generates a wide spectrum of different address sequences, including the stand-ard ones, such as linear, address com-plement, gray code, worst-case gate delay, 2i, next address, and pseudoran-dom. Examples of the use of the pro-posed methods are considered. The result of the practical implementation of the UASG is presented, and the main characteristics are evaluated

Application of Western blotting for the detection of uncoupling protein-2 (UCP-2) in mitochondria from smokers and non-smokers

Introduction: Uncoupling proteins (UCPs) are a family of transmembrane anion transporters present in the inner mitochondrial membrane. UCP-2, which exhibits the widest distribution in various tissues, plays an important role in many physiological processes. Human UCP-2 studies have been hampered by the lack of a method for measuring this protein in an easily accessible human tissue, e.g. blood. The aim of this study was to develop such a method and test its utility by comparing UCP-2 levels in smokers and non-smokers. Material and methods: Venous blood samples from 10 smoking and seven non-smoking volunteers were used for the study; lymphocytes were isolated employing Lymphoprep. UCP-2 levels were measured by Western blotting combined with chemoluminescence detection. Results: Total lymphocyte homogenates were found useless for measuring UCP-2 levels, but it was possible to measure UCP-2 in homogenates of purified lymphocyte mitochondria. There was a significant, though moderate, linear correlation between UCP-2 level and daily cigarette use. UCP-2 level in peripheral blood lymphocytes from smokers was higher than that in non-smokers. Conclusion: The method for measuring UCP-2 in peripheral blood lymphocytes opens the possibility of UCP-2 screening studies in humans and thus may be useful for studying the role of the protein in human physiology and pathology.Wstęp: Białka rozprzęgające (UCPs) stanowią rodzinę białek transportujących aniony przez wewnętrzną błonę mitochondrialną. Białko UCP-2 - które jest najszerzej rozpowszechnione w tkankach - odgrywa ważną rolę w wielu procesach fizjologicznych. Badanie funkcji tego białka u ludzi było utrudnione z powodu braku prostych metod jego pomiaru w łatwo dostępnych tkankach, na przykład we krwi. Celem tej pracy było opracowanie takiej metody i wykonanie pilotowego badania jej przydatności przez porównanie ekspresji białka UCP-2 u osób palących i niepalących. Materiał i metody: W badaniu wzięło udział 17 ochotników (10 osób palących i 7 niepalących), od których pobrano krew żylną. Z krwi izolowano limfocyty za pomocą Lymphoprepu. Ekspresję UCP-2 oceniano metodą Western blot z detekcją chemoluminescencyjną. Wyniki: Homogenat całych limfocytów krwi obwodowej okazał się nieprzydatny do mierzenia poziomu UCP-2, wykazano zaś, że dobrym materiałem do takich oznaczeń jest homogenat oczyszczonych mitochondriów z tych komórek. Stwierdzono wyższą ekspresję UCP-2 u osób palących oraz istotną, chociaż umiarkowaną, liniową korelację między ekspresją UCP-2 a liczbą dziennie wypalanych papierosów. Wnioski: Opisana metoda oznaczania UCP-2 umożliwia prowadzenie badań przesiewowych nad rolą tego białka w stanach fizjologicznych i patologicznych u ludzi

ПСЕВДОИСЧЕРПЫВАЮЩЕЕ ТЕСТИРОВАНИЕ ОЗУ

Modern RAM tests and methods for their generation are analyzed and investigated. The wide application of pseudoexhaustive tests as the main test procedure for modern computer systems has been proved. The main estimates and metrics for so kind of tests are obtained. The values of analytical estimates have been validated by the experimental investigations.Анализируются методы тестирования современных запоминающих устройств, в том числеоперативных запоминающих устройств (ОЗУ), обосновывается применение псевдоисчерпывающих тестов для обнаружения сложных неисправностей памяти. Формулируется необходимое условие генерирования псевдоисчерпывающего теста для заданного количества запоминающих ячеек ОЗУ. Показывается, что задача генерирования псевдоисчерпывающего теста на базе многократных тестов ОЗУ с изменяемыми адресными последовательностями сводится к комбинаторной задаче собирателя купонов. Приводятся оценки минимальной, максимальной и средней кратности многократного теста для обеспечения исчерпывающего множества комбинаций для заданного числа ячеек ОЗУ, что подтверждает возможность формирования псевдоисчерпывающего теста для заданного числа ячеек ОЗУ

Псевдоисчерпывающее тестирование запоминающих устройств на базе маршевых тестов типа March A

The relevance of testing of memory devices of modern computing systems is shown. The methods and algorithms for implementing test procedures based on classical March tests are analyzed. Multiple March tests are highlighted to detect complex pattern-sensitive memory faults. To detect them, the necessary condition that test procedures must satisfy to deal complex faults, is substantiated. This condition is in the formation of a pseudo-exhaustive test for a given number of arbitrary memory cells. We study the effectiveness of single and double application of tests like MATS ++, March C– and March A, and also give its analytical estimates for a different number of k ≤ 10 memory cells participating in a malfunction. The applicability of the mathematical model of the combinatorial problem of the coupon collector for describing multiple memory testing is substantiated. The values of the average, minimum, and maximum multiplicity of multiple tests are presented to provide an exhaustive set of binary combinations for a given number of arbitrary memory cells. The validity of analytical estimates is experimentally shown and the high efficiency of the formation of a pseudo-exhaustive coverage by tests of the March A type is confirmed.Показывается актуальность тестирования запоминающих устройств современных вычислительных систем. Анализируются методы и алгоритмы реализации тестовых процедур на базе классических маршевых тестов. Выделяются многократные маршевые тесты, позволяющие обнаруживать сложные кодочувствительные неисправности памяти. Для их обнаружения обосновывается необходимое условие, которому должны удовлетворять тестовые процедуры для покрытия сложных неисправностей. Это условие заключается в формировании псевдоисчерпывающего теста для заданного количества произвольных ячеек памяти. Исследуется эффективность однократного и двукратного применения тестов типа MATS++, March C- и March A, а также приводятся ее аналитические оценки для различного количества k ≤10 ячеек памяти, участвующих в неисправности. Обосновывается применимость математической модели комбинаторной задачи собирателя купонов для описания многократного тестирования памяти. Приводятся значения средней, минимальной и максимальной кратности многократных тестов для обеспечения исчерпывающего множества двоичных комбинаций для заданного числа произвольных ячеек памяти. Экспериментально показывается справедливость аналитических оценок и подтверждается высокая эффективность формирования псевдоисчерпывающего покрытия тестами типа March A

ПСЕВДОИСЧЕРПЫВАЮЩЕЕ ТЕСТИРОВАНИЕ ЗАПОМИНАЮЩИХ УСТРОЙСТВ НА БАЗЕ МНОГОКРАТНЫХ МАРШЕВЫХ ТЕСТОВ

Methods for modern memory devices are analyzed. The validity of using pseudo-exhaustive tests to detect complex memory faults is shown. A necessary condition for generating a pseudo-exhaustive test for a given number of memory cells is formulated. It is shown that the problem of generating a pseudo-exhaustive test based on multiple memory tests with a variable background is reduced to the combinatorial task of the coupon collector. Estimates of the mean, minimum, and maximum multiplicity of a multiple test are given to provide an exhaustive set of combinations for a given number of cells of a memory device. The validity of analytical estimates is shown experimentally and the possibility of pseudo-exhaustive memory testing is confirmed.Анализируются методы тестирования современных запоминающих устройств. Показывается обоснованность применения псевдоисчерпывающих тестов для обнаружения сложных неисправностей памяти. Формулируется необходимое условие генерирования псевдоисчерпывающего теста для заданного количества ячеек запоминающего устройства. Показывается, что задача генерирования псевдоисчерпывающего теста на базе многократных тестов запоминающих устройств с изменяемым начальным состоянием сводится к комбинаторной задаче собирателя купонов. Приводятся оценки средней, минимальной и максимальной кратности многократного теста для обеспечения исчерпывающего множества комбинаций для заданного числа ячеек запоминающего устройства. Экспериментально показывается справедливость аналитических оценок и подтверждается возможность псевдоисчерпывающего тестирования запоминающих устройств.