scholarly journals A New Axial-Radial “Isotherm” Compressor

1974 ◽  
Author(s):  
R. A. Strub

It is known that the compression work of gases can be largely reduced by inter-stage cooling. Multistage radial compressors have been developed in the past with coolers integrated within the casing. Such a solution, however, is limited to medium volume flows of about 40 m3/s. For larger flows, a combination comprising an axial low pressure section with variable guide vanes for flow regulation, used as supercharger, followed by a multistage radial section with integrated coolers, has been developed. The major parameters governing this choice are presented. Aerodynamic tests on the axial and radial sections have been carried out with a special emphasis on the aerodynamic layout of the diffusor connecting the axial or the radial sections to the coolers. The tests have shown that a considerable amount of aerodynamic improvement could be obtained by a proper disposition of asymmetrical guide vanes dividing the total flow going to the coolers placed symmetrically on each side of the casing. Test results on the complete machine, regarding its aerodynamic characteristics and the noise level as well as its mechanical behavior, are given.

2016 ◽  
Vol 17 (4) ◽  
pp. 975-984
Author(s):  
A. W. Schmalwieser

The only practicable way to control the disinfection capability of a UV disinfection plant for drinking water all the time is to use a UV radiometer. According to the Austrian Standard M5873, this plant radiometer is a standardized part of each plant. The standard defines a so-called reference radiometer (RRM) as well. This is necessary because a plant radiometer has to be controlled periodically. A RRM is a hand-held device which has to fulfil high-quality criteria and must be almost insensitive to environmental conditions. In this paper the principles of the concept behind the RRM are explained together with the requirements of such a device. Further on, the test methods are presented as well as a summary of test results from all RRMs developed during the past 15 years. It is shown that the radiation monitoring concept of the Austrian Standard has been successfully practicable and that the international acceptance of the Austrian Standard is justified.


2021 ◽  
pp. 1-11
Author(s):  
P. N. R. L. Chandra Sekhar Author ◽  
T. N. Shankar Author

In the era of digital technology, it becomes easy to share photographs and videos using smartphones and social networking sites to their loved ones. On the other hand, many photo editing tools evolved to make it effortless to alter multimedia content. It makes people accustomed to modifying their photographs or videos either for fun or extracting attention from others. This altering brings a questionable validity and integrity to the kind of multimedia content shared over the internet when used as evidence in Journalism and Court of Law. In multimedia forensics, intense research work is underway over the past two decades to bring trustworthiness to the multimedia content. This paper proposes an efficient way of identifying the manipulated region based on Noise Level inconsistencies of spliced mage. The spliced image segmented into irregular objects and extracts the noise features in both pixel and residual domains. The manipulated region is then exposed based on the cosine similarity of noise levels among pairs of individual objects. The experimental results reveal the effectiveness of the proposed method over other state-of-art methods.


Author(s):  
J. Shi

Scatter in test results is common for relatively brittle materials such as ceramic matrix composites. The scatter may come from differences in material processing conditions, specimen machining/handling and from variations in test parameters for nominally the same test material. Large scatter in test results makes material modeling difficult. In the past, master curve concepts have been proposed to reduce scatter in tensile data and to interpret fatigue/creep results. In this paper, one such concept is examined in detail by applying it to the recent tensile test results of a SiC/SiC composite. It was found that the way to construct master curves did not apply to the CMC studied and thus a new master curve was developed to better represent the tensile data. In addition, the test data were analysed statistically based on the new master curve.


2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Zude Ding ◽  
Jincheng Wen ◽  
Xiafei Ji ◽  
Zhihua Ren ◽  
Sen Zhang

The presence of voids or lining thinning directly affects the mechanical behavior of linings, and these defects threaten the safety of tunnel operation. In this study, a series of 1/5-scale model tests was used to investigate the mechanical behavior of normal concrete (NC) linings in consideration of voids and combined defects. Test results showed that the void and combined defects substantially reduced the load-bearing capacity and deformation properties of the linings. The inelastic mechanical behavior of the linings was also significantly affected by the defects. The effects of lining defects located at the spandrel were slightly weaker than those of lining defects located at the crown. As the void size or degree of combined defects increased, the tensile strain at the location of the lining defects also increased. Therefore, the defect position of the linings was easily damaged. The defects considerably reduced the overall deformation of the linings but increased the local deformation. The distribution of lining cracks was concentrated at the defect position. In addition, different failure characteristics of the lining were observed due to the differences in defects.


AI Magazine ◽  
2015 ◽  
Vol 36 (3) ◽  
pp. 49-60 ◽  
Author(s):  
Randall Davis ◽  
David Libon ◽  
Roda Au ◽  
David Pitman ◽  
Dana Penney

The digital clock drawing test is a fielded application that provides a major advance over existing neuropsychological testing technology. It captures and analyzes high precision information about both outcome and process, opening up the possibility of detecting subtle cognitive impairment even when test results appear superficially normal. We describe the design and development of the test, document the role of AI in its capabilities, and report on its use over the past seven years. We outline its potential implications for earlier detection and treatment of neurological disorders. We set the work in the larger context of the THink project, which is exploring multiple approaches to determining cognitive status through the detection and analysis of subtle behaviors.


2012 ◽  
Vol 212-213 ◽  
pp. 1057-1061 ◽  
Author(s):  
Zhong Liu ◽  
Zhu Qing Huang ◽  
Shu Yun Zou ◽  
Hong De Rao

The 3# bulb turbine in Hongjiang Hydropower Plant has faced the problem of output deficiency since its commission in Sept. 2003, which caused a large economic loss. Following simple theoretical analyses on the main factors affecting the turbine’s output and efficiency, the field test schemes were determined to measure the shapes and intervals of guide vanes and runner blades of the 3#, 5# and 6# turbines. The test results discover that the average blade intervals of the 3# turbine are generally less than those of the 5# one. Suggestions on runner blade installation adjustment and combined curve modification are given.


2017 ◽  
Vol 55 (8) ◽  
pp. 1112-1114 ◽  
Author(s):  
Giuseppe Lippi ◽  
Gianfranco Cervellin ◽  
Mario Plebani

AbstractThe management of laboratory data in unsuitable (hemolyzed) samples remains an almost unresolved dilemma. Whether or not laboratory test results obtained by measuring unsuitable specimens should be made available to the clinicians has been the matter of fierce debates over the past decades. Recently, an intriguing alternative to suppressing test results and recollecting the specimen has been put forward, entailing the definition and implementation of specific algorithms that would finally allow reporting a preanalytically altered laboratory value within a specific comment about its uncertainty of measurement. This approach carries some advantages, namely the timely communication of potentially life-threatening laboratory values, but also some drawbacks. These especially include the challenging definition of validated performance specifications for hemolyzed samples, the need to producing reliable data with the lowest possible uncertainty, the short turnaround time for repeating most laboratory tests, the risk that the comments may be overlooked in short-stay and frequently overcrowded units (e.g. the emergency department), as well as the many clinical advantages of a direct communication with the physician in charge of the patient. Despite the debate remains open, we continue supporting the suggestion that suppressing data in unsuitable (hemolyzed) samples and promptly notifying the clinicians about the need to recollect the samples remains the most (clinically and analytically) safe practice.


1940 ◽  
Vol 44 (352) ◽  
pp. 338-349
Author(s):  
A. P. West

During the past few years an extensive amount of experimental data on split flaps has been made available to the aircraft industry, through the publications of aeronautical research laboratories, both in this country and abroad. In general, each publication deals with one particular aspect of the problem, and when the effect of wing flaps on the performance of an aircraft is being estimated a certain amount of difficulty may be experienced in deciding which of the many reports available gives results most readily applicable to the case being considered ; and what allowances, if any, should be made for wing taper, flap cut-out, fuselage, etc.In this report the available data has been analysed with a view to answering these questions, and presented in such a form that it may be readily applied to determine the most probable change in the aerodynamic characteristics of a wing that may be expected from the use of this type of flap.From the appendix an estimate of the accuracy of the method can be obtained, as a comparison with full-scale data is given for lift and drag, and for the other flap characteristics the original curves have been reproduced.


2019 ◽  
Vol 2 (1) ◽  
pp. 8-14
Author(s):  
Beauty Novianty ◽  
Ella Amalia ◽  
Ziske Maritska ◽  
Yuwono Yuwono ◽  
Lusia Hayati

Background: Over the past decade, numbers of Carbapenemase Producing-Carbapenem Resistant Enterobacteriaceae (CP-CRE) has been increasing worldwide and it has been becoming a threat because of its resistance against carbapenem which is considered as the “last resort” antibiotic. Therapy options for its infection are still limited. Aminoglycoside serves as one of the most commonly used antibiotics, but the resistance against it has already been presented for a long time. Aminoglycoside Modifying Enzyme (AME) is the most important resistance mechanism against aminoglycoside. AAC(6’)-Ib enzyme is one of the most common AME produced by the gram-negative bacteria.Objectives: This study wished to identify the gene of this enzyme among CRE isolated from infected Indonesian patients in Dr. Mohammad Hoesin Hospital Palembang.Methods: Twenty-eight isolates collected from CRE-infected patients identified by Vitek 2 Compact (bioMerieux, USA) in dr. Mohammad Hoesin Hospital Palembang during September—November 2017. AAC(6’)-Ib gene was identified using PCR method, then visualize by electrophoresis. The result is then analyzed by comparing it with a susceptibility test.  Results: Out of 28 samples, AAC(6’)-Ib is identified in 22 (78.57%) samples. Samples with AAC(6’)-Ib showed to be less resistant to various antibiotics, significantly to amikacin (p=0.023).Conclusion: AAC(6’)-Ib gene is found in most of samples implying its frequent occurrence in Indonesian patients.


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