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Methods of Fault Diagnosis in Fiber Optic Current Transducer Based on Allan Variance
No full textTo ensure low failure and high reliability of fiber optic current transducers (FOCTs), it is urgent to study methods of condition monitoring and fault diagnosis in FOCT. Faults in FOCT have statistical characteristics. With the analyzing of time domain and frequency domain features in fiber optic current transformers' measurement data, we establish correspondence between the physical characteristics of key components in transformer and data features and then build diagnostic analysis model based on Allan variance. According to the Allan variance calculation results, we can diagnose fiber optic current transformer's health state and realize faults location. Experiment results show that diagnostic methods based on Allan variance are accurate and effective to identify fault features
Original Articles Advance Directives and Do-Not-Resuscitate Orders in Patients with Cancer with Metastatic Spinal Cord Compression: Advanced Care Planning Implications
No full textAbstract Objectives: Communication about end-of-life decisions is crucial. Although patients with metastatic spinal cord compression (MSCC) have a median survival time of 3 to 6 months, few data are available concerning the presence of advance directives and do-not-resuscitate (DNR) orders in this population. The objective of this study was to determine presence of advance directives and DNR order among patients with MSCC. Methods: We retrospectively reviewed data concerning advance directives for 88 consecutive patients with cancer who had MSCC and required rehabilitation consultation at The University of Texas M. D. Anderson Cancer Center from September 20, 2005 to August 29, 2008. We characterized the data using univariate descriptive statistics and used the Fisher exact test to find correlations. Results: The mean age of this patient population was 55 years (range, 24-81). Thirty patients (33%) were female. Twenty patients (23%) had a living will, 27 patients (31%) had health care proxies, and 10 patients (11%) had either out-of-hospital DNR order and=or dictated DNR note. The median survival time for these patients was 4.3 months. Conclusion: Despite strong evidence showing short survival times for MSCC patients, it seems many of these patients are not aware of the urgency to have an advance directive. This may be an indicator of delayed end-oflife palliative care and suboptimal doctor-patient communication. Using the catastrophic event of a diagnosis of MSCC to trigger communication and initiate palliative care may be beneficial to patients and their families
Coupling hierarchical word reordering and decoding in phrase-based statistical machine translation
No full textAbstract In this paper, we start with the existing idea of taking reordering rules automatically derived from syntactic representations, and applying them in a preprocessing step before translation to make the source sentence structurally more like the target; and we propose a new approach to hierarchically extracting these rules. We evaluate this, combined with a lattice-based decoding, and show improvements over stateof-the-art distortion models
2007, Schumpeterian technology shocks
No full textAbstract We analyze the effects of neutral and investment-specific technology shocks on hours worked and unemployment. We characterize the response of unemployment in terms of job separation and job finding rates. Job separation rates mainly account for the impact response of unemployment while job finding rates for movements along its adjustment path. Neutral shocks increase unemployment and explain a substantial portion of unemployment and output volatility; investment-specific shocks expand employment and hours worked and mostly contribute to hours worked volatility. This evidence is consistent with the view that neutral technological progress prompts Schumpeterian creative destruction, while investment specific technological progress has standard neoclassical features. JEL classification: E00, J60, O33
Physical stability of drugs after storage above and below the glass transition temperature: Relationship to glass-forming ability
No full textA B S T R A C T Amorphous materials are inherently unstable and tend to crystallize upon storage. In this study, we investigated the extent to which the physical stability and inherent crystallization tendency of drugs are related to their glass-forming ability (GFA), the glass transition temperature (T g ) and thermodynamic factors. Differential scanning calorimetry was used to produce the amorphous state of 52 drugs [18 compounds crystallized upon heating (Class II) and 34 remained in the amorphous state (Class III)] and to perform in situ storage for the amorphous material for 12 h at temperatures 20 C above or below the T g . A computational model based on the support vector machine (SVM) algorithm was developed to predict the structure-property relationships. All drugs maintained their Class when stored at 20 C below the T g . Fourteen of the Class II compounds crystallized when stored above the T g whereas all except one of the Class III compounds remained amorphous. These results were only related to the glass-forming ability and no relationship to e.g. thermodynamic factors was found. The experimental data were used for computational modeling and a classification model was developed that correctly predicted the physical stability above the T g . The use of a large dataset revealed that molecular features related to aromaticity and p-p interactions reduce the inherent physical stability of amorphous drugs
ICEF2005-1220 A SIMULATION OF THE COMBUSTION OF N-HEPTANE FUELED HCCI ENGINES USING A 3-D MODEL WITH DETAILED CHEMICAL KINETICS
No full textABSTRACT A CFD multi-dimensional computational approach has been developed through a combination of a modified KIVA3 code together with a detailed chemical kinetics scheme for the oxidation of n-heptane in air while considering the effects of turbulence. The effects of adding different quantities of hydrogen, methane and carbon monoxide to the heptane on the combustion characteristics of the HCCI engine under different conditions were investigated both experimentally and numerically. The effects of changes in the combustion chamber wall surface temperature on the combustion characteristics of the HCCI engine were examined. It was found that the presence with n-heptane of some hydrogen, methane or carbon monoxide could delay to various extents the autoignition, while changes in the values of the combustion chamber wall temperature influence the autoignition timing and its initial location. It is suggested that the supplementing of the liquid fuel with gaseous fuels and /or application of a suitable glow-plug surface of optimum size and location fitted with temperature control may aid in controlling the combustion process of an HCCI engine while obtaining higher power output without producing knock
Chlorine-36 evidence for the mono lake event in the summit grip ice core, Earth Planet
No full textAbstract A distinct peak has been discovered in the 36 Cl data from the GRIP ice core between the Dansgaard Oeschger (D^O) events 6 and 7 at approximately 32 kyr BP. This peak can be attributed to a minimum of the geomagnetic dipole field associated with the Mono Lake event. Since the 36 Cl peak reflects a higher production rate of all cosmogenic radionuclides, it has an impact on the 14 C dating of the last ice age. Furthermore, it provides an additional time marker similar to a peak found earlier corresponding to the Laschamp event at approximately 39 kyr BP.
ECO-DESIGN- O NOUA ABORDARE
No full textAbstract: In addition to sorption processes within the hygroscopic range, water absorption at direct water contact plays another important role in the field of building physics. Therefore, the water absorption coefficient was measured for Norway spruce (Picea abies [L.] Karst.) and European beech (Fagus sylvatica L.) INTRODUCTION In addition to sorption processes within the hygroscopic range, water absorption at direct water contact plays another important role in the field of building physics. Therefore, the water absorption coefficient was measured for Norway spruce (Picea abies [L.] Karst.) and European beech (Fagus sylvatica L.) in the principal anatomical directions. Thereby, the influence of sapwood and heartwood and of antecedent freezing was investigated. Temporary freezing of wood was already applied at various occasions to upgrade the wood properties (Ilic 1995). Thereby, the assumption is given, that prefrozen wood increases the water path through a higher permeability and therefore decreases the drying time. At most, however, it was used to reduce swelling and thereof generated failures during drying. Investigations into this technique were primarily located in the United States and Australia. An overview of these investigations is shown by MATERIAL AND METHOD The material originated from the lower four meters of a spruce and a beech tree grown in the Federal Institute of Technology's research forest in Zurich. Boards with dimensions 65cm (length) x 10cm (thickness) were cut from logs. Thereafter, three-quarter of the green boards were frozen for 48, 77 or 120 hours at -40°C and then all boards were air-conditioned at normal climate of 20°C and 65% RH and cubes sized 5cm and oriented in the principal anatomical directions were cut from them. In addition, from similar cubes of spruce and beech wood from the region of Zurich that were previously air-conditioned at normal climate, also three-quarter were frozen for 48, 77 or 120 hours at -40°C and then again air-conditioned at normal climate. After reaching equilibrium MC, the water absorption was determined on the cubes in the tangential, radial and longitudinal directions according to ISO 15148 (2002). RESULTS AND DISCUSSION The water absorption coefficients within all directions show a wide spread for both investigated species The specified values of the water absorption coefficients for spruce are shown in At the green prefrozen specimens, sapwood shows higher values than heartwood. This is due to the fact that heartwood possesses a higher portion of extractives and the water conduction within the tracheids is interrupted (cf. Bosshard 1984). The influence of prefreezing is low but higher for the green prefrozen specimens than for the specimens that were first conditioned at normal climate, and additionally the influence of density is superimposed. Therefore, investigations with a higher number of specimens are necessary to verify the influence of prefreezing. CONCLUSION The water absorption coefficient was measured for spruce and beech in the principal anatomical directions. The values were widely spread in all directions and were clearly higher for beech than for spruce. A significant influence of the prefreezing was only shown for green prefrozen beech in the tangential and longitudinal directions. For further investigations, a higher number of specimens with similar density distributions per type are necessary for a more accurate quantification of the influences of density and prefreezing
Analysis of the Placental Tissue Transcriptome of Normal and Preeclampsia Complicated Pregnancies
No full textabStract Preeclampsia is one of the most severe gestational complications which is one of the leading causes of maternal and perinatal morbidity and mortality. A growth in the incidence of severe and combined forms of the pathology has been observed in recent years. According to modern concepts, inadequate cytotrophoblast invasion into the spiral arteries of the uterus and development of the ischemia-reperfusion syndrome in the placental tissue play the leading role in the development of preeclampsia, which is characterized by multipleorgan failure. In this regard, our work was aimed at studying the patterns of placental tissue transcriptome that are specific to females with PE and with physiological pregnancy, as well as identifying the potential promising biomarkers and molecular mechanisms of this pathology. We have identified 63 genes whose expression proved to differ significantly in the placental tissue of females with PE and with physiological pregnancy. A cluster of differentially expressed genes (DEG) whose expression level is increased in patients with preeclampsia includes not only the known candidate genes that have been identified in many other genome-wide studies (e.g., LEP, BHLHB2, SIGLEC6, RDH13, BCL6), but also new genes (ANKRD37, SYDE1, CYBA, ITGB2, etc.), which can be considered as new biological markers of preeclampsia and are of further interest. The results of a functional annotation of DEG show that the development of preeclampsia may be related to a stress response, immune processes, the regulation of cell-cell interactions, intracellular signaling cascades, etc. In addition, the features of the differential gene expression depending on preeclampsia severity were revealed. We have found evidence of the important role of the molecular mechanisms responsible for the failure of immunological tolerance and initiation of the pro-inflammatory cascade in the development of severe preeclampsia. The results obtained elaborate the concept of the pathophysiology of preeclampsia and contain the information necessary to work out measures for targeted therapy of this disease
