Influence of Running Conditions on Resonant Oscillations in Fresh-Air Ventilator Blades Used in Thermal Power Plants

High-frequency cyclic load of fresh air supply to ventilator blades in thermo energetic facilities can cause the occurrence of fretting in the pressed overlap of ventilator shaft and socket. These loads can be generated by the resonant oscillations of ventilator blades and thermal residual stress due to welding. To prevent running in resonant conditions, the manufacturer of the ventilator defined a procedure of adjusting blades natural frequency in the process of production, as well as period control during exploitation period The numerical simulations and the accelerations measured and presented in this paper, enabling analysis of mass changes and rotation rate effects on resonant oscillations occurrence in fresh air ventilator

The widow maker warning sign or wellens' syndrome: A case report

Wellens' syndrome, also known as LAD (left anterior descending) coronary T-wave syndrome, widow maker or warning sign, is a potentially unrecognized critical proximal LAD stenosis with possible fatal consequences. It can be associated with extensive acute anterior wall myocardial infarction, with left ventricular dysfunction and a lethal outcome within a few days after the onset of symptoms. It usually consists of a typical ECG finding in the precordial leads that represents a significant proximal LAD stenosis in patients with unstable angina pectoris. Although this syndrome is not indicated for PCI (the patient is usually pain-free at the time of electrocardiography registration), it is necessary to recognize the characteristic pattern and perform an emergency coronary angiography and percutaneous or surgical revascularisation of the affected blood vessel. Here we present the case report of a 47 year-old woman without previous anamnesis of coronary disease. On admission to the Coronary Care Unit she was chest pain-free and had all the indicators of Wellens' syndrome

Triangulation of Convex Polygon with Storage Support

Unlike the algorithms for convex polygon triangulation which make the triangulation of an n-gon from the scratch, we propose the algorithm making the triangulation of an (n+1)-gon on the base of already found triangulations of an n-gon. For such a purpose we must maintain suitable file storage to store previously derived triangulations and later use them to generate the triangulations of polygon with one more vertex. The file storage is partially exploited for elimination of duplicates our algorithm produces. Yet, triangulation and elimination of duplicates do not critically decrease our algorithm performances for smaller values of n

Fractional flow reserve of intermediate lesions on collateral donor coronary arteries after myocardial infarction

Fractional flow reserve (FFR) is the gold standard for the functional assessment of coronary arteries. The aim of this study was to evaluate the relation between angiography, QCA and FFR in borderline lesions on collateral donor coronary arteries. In addition, FFR is compared with the angiographic appearance of collaterals to infarction-related arteries and echocardiographically assessed viability of infarct related the LV wall. In 60 patients with previous IM and occluded IRA, functional assessment of borderline coronary stenosis (30-70% DS) on collaterals donor artery was performed. We have not found statistically significant differences in these parameters between groups with different angiographic appearances of collaterals and different viability of distal myocardium. However, we found higher FFR values in diabetic patients (p=0.018). Higher FFR values in diabetic patients reveal the negative effects of diabetes on collateral growth and myocardial viability

INTER-ORGANIZATIONAL COLLABORATION FOR INNOVATION IN MANUFACTURING FIRMS

From day to day, taking part in the collaboration process in different business aspects, especially in the innovation process continues to gain in importance. Innovation enables companies to strive for a more powerful market position, while inter-organizational cooperation is perceived as an efficient means of enhancement of firm innovativeness. The purpose of this paper is to present the state of inter-organizational collaboration for innovation among manufacturing companies in Vojvodina, analyzing cooperation among manufacturing firms with different external parties, in different innovation areas. Furthermore, the aim is to examine the effects of inter-organizational collaboration on the innovativeness of manufacturing firms in Vojvodina. The data used in this paper was gathered within the international project European Manufacturing Survey. The results are presented using descriptive statistics and they demonstrate that the existence and frequency of inter-organizational collaboration, although quite present, depends on external parties as potential cooperation partners and on different innovation areas in which collaboration could occur. Also, the research shows there is a notable relation between interorganizational collaboration and firm innovativeness

Intracerebral hemorrhage as a first sign of pheochromocytoma: case report and review of the literature

Pheochromocytomas and sympathetic paragangliomas are rare catecholamine-secreting tumours that represent very rare causes of intracerebral haemorrhage in the young, with only a few cases reported. A 32-year-old man presented to our emergency department because of sudden onset of severe headache. He had a six-month history of paroxysmal headache, palpitations, and sweating. During examination he became somnolent and developed left-sided hemiplegia. A computed tomographic (CT) scan of the brain showed a right temporoparietal haematoma. He was admitted to the Clinic for Neurosurgery and the haematoma was evacuated. The patient was comatose, on assisted respiration, with frequent hypertensive crises. An examination for possible secondary causes of hypertension was undertaken. Plasma metanephrine value was elevated (414 pg/mL, reference values < 90 pg/mL). Abdominal CT scans revealed a large mass (6 cm) in the right adrenal gland. After adequate control of the hypertension was achieved with nonselective alpha- and beta-adrenergic blockers the tumour was excised. The histopathologic findings confirmed the diagnosis of pheochromocytoma. The genetic analysis demonstrated a duplication in exon 1 of the VHL gene. We reported a rare, potentially fatal complication of pheochromocytoma — an intracerebral haemorrhage. This case and review of similar rare cases in the literature illustrate the importance of early recognition of the characteristic symptoms of catecholamine excess in young patients with hypertension

Use of Spatiotemporal Constraints to Quantify Transit Accessibility Case Study of Potential Transit-Oriented Development in West Valley City, Utah

Accessibility emerges as the transportation performance measure that emphasizes the benefits to transportation system users and captures more than the speed of travel. Transit accessibility shows how easy it is for an individual to travel to a desired destination by using public transit. However, for transit to be considered as an option in mode choice at all, there has to be a feasible transit route leading from a given origin to a desirable destination within the available time frame. This study used spatial and temporal constraints and a set of transit features that affected access to transit to develop a conceptual framework for transit accessibility measurements in a potential transit-oriented development (TOD) location in West Valley City, Utah. As this network develops more transit-friendly features, temporal and spatial accessibility indicators will provide useful information on the opportunities that users can reach by using transit. The proposed methodology was based on traffic and transit data from the case study network and used an open source tool to perform transit accessibility measurements by calculating the number of accessible transit stops from each origin. The methodology considered network features, acceptable walking time, available time budget, transit schedule variability, and spatial constraints as impact factors in accessibility measurements. The goal of the study was to establish a feasible set of transit accessibility indicators that would be used for both the case study street network and transit service modifications to transform the network into a transit-friendly and eventually a TOD environment

Weighted Moore–Penrose generalized matrix inverse: MySQL vs. Cassandra database storage system

© 2016, Indian Academy of Sciences. The research in this paper refers to two areas: programming and data storage (data base) for computing the weighted Moore–Penrose inverse. The main aim of this paper analysis of the execution speed of computing using PHP programming language and data store. The research shows that the speed of execution gives considerable difference between the Procedural programming and Object Oriented PHP language, on the middle layer in the three tier of the web architecture. Also, the research concerning the comparison of relation database system, MySQL and NoSQL, key value store system, ApacheCassandra, on the database layer. The CPU times are compared and discussed