Ultrasonic Method for Monitoring Environmental Risks Associated with Precipitation

2013 ◽  
Vol 38 (1) ◽  
pp. 125-135 ◽  
Author(s):  
Tadeusz Gudra ◽  
Dariusz Banasiak ◽  
Krzysztof Herman ◽  
Krzysztof Opieliński

Abstract This paper presents a solution that utilises ultrasonic technology to allow monitoring snow layer thickness or water level based on measurement from air. It describes the principle of operation of a measurement device using three methods of compensating for changing external factors affecting appliance’s precision. Block diagram of the device is also provided. In order to verify the proposed solutions, the research team tested the device in laboratory and operating conditions. The results obtained this way make it possible to select a configuration of device operation depending on the required measurement precision and limitations associated with installing the system for actual operation.

Author(s):  
Nikolaj Dobrzinskij ◽  
Algimantas Fedaravicius ◽  
Kestutis Pilkauskas ◽  
Egidijus Slizys

Relevance of the article is based on participation of armed forces in various operations and exercises, where reliability of machinery is one of the most important factors. Transportation of soldiers as well as completion of variety of tasks is ensured by properly functioning technical equipment. Reliability of military vehicles – armoured SISU E13TP Finnish built and HMMWV M1025 USA built were selected as the object of the article. Impact of climatic conditions on reliability of the vehicles exploited in southwestern part of the Atlantic continental forest area is researched by a case study of the vehicles exploitation under conditions of the climate of Lithuania. Reliability of military vehicles depends on a number of factors such as properties of the vehicles and external conditions of their operation. Their systems and mechanisms are influenced by a number of factors that cause different failures. Climatic conditions represent one of the factors of operating load which is directly dependent on the climate zone. Therefore, assessment of the reliability is started with the analysis of climatic factors affecting operating conditions of the vehicles. Relationship between the impact of climatic factors and failure flow of the vehicles is presented and discussed.


Author(s):  
Noman Yousuf ◽  
Timothy Anderson ◽  
Roy Nates

Abstract Despite being identified nearly a century ago, the diffusion absorption refrigeration (DAR) cycle has received relatively little attention. One of the strongest attractions of the DAR cycle lies in the fact that it is thermally driven and does not require high value work. This makes it a prime candidate for harnessing low grade heat from solar collectors, or the waste heat from stationary generators, to produce cooling. However, to realize the benefits of the DAR cycle, there is a need to develop an improved understanding of how design parameters influence its performance. In this vein, this work developed a new parametric model that can be used to examine the performance of the DAR cycle for a range of operating conditions. The results showed that the cycle's performance was particularly sensitive to several factors: the rate of heat added and the temperature of the generator, the effectiveness of the gas and solution heat exchangers, the mass flowrate of the refrigerant and the type of the working fluid. It was shown that can deliver good performance at low generator temperatures if the refrigerant mass fraction in the strong solution is made as high as possible. Moreover, it was shown that a H2O-LiBr working pair could be useful for achieving cooling at low generator temperatures.


2020 ◽  
Vol 26 (10) ◽  
pp. 82-87
Author(s):  
Lin Peng ◽  

Many businesses that work with a large number of product lines face the problem of choosing a supplier of goods or services. The problem of finding suppliers is faced by most businesses that do business and are looking for new ways to optimize costs. Enterprises need to periodically search for suppliers, and this is much more difficult for them due to lack of experience, especially in relations with foreign suppliers. Procurement planning is carried out by selecting suppliers who must meet previously established criteria set by the company’s standards and legislation. The search and analysis of suppliers should be carried out systematically using all possible sources of information. At the present stage, conservative methods of searching, analyzing and selecting suppliers are being improved and supplemented with new forms and methods, but none of the existing methods of selecting a supplier properly takes into account the current operating conditions. Therefore, supply chain management is particularly relevant and requires improvement. The article suggests a model that allows identifying potentially unscrupulous suppliers even before the contract is executed in the supply chain and using management. The article presents a block diagram of the supply chain risk management model. The model specifies a key condition aimed at combining the work of all departments in order to increase the transparency of procedures. At the same time, the model will reduce the risks of the supply chain and improve the process of making logistics decisions within 3 main blocks. Information about the entire lifecycle of equipment, media, and items is stored in the supply chain information system, reflecting the status and attributes of all aspects and providing a variety of data support for decision - making


Author(s):  
Xiaowei Fan ◽  
Fang Wang ◽  
Huifan Zheng ◽  
Xianping Zhang ◽  
Di Xu

The refrigerant mixtures provide an important direction in selecting new environment-friendly alternative to match the desirable properties with the existing halogenated refrigerants or future use in the new devices, in which, HFCs refrigerants with zero ODP combined with HCs refrigerants with zero ODP and lower GWP are of important value in the fields of application. In the present work, research on HFC125/HC290 (25/75 by mass) binary refrigerant mixture used in heat pumps was carried out, and parameters, factors affecting the performance were investigated, and compared with that of HCFC22 under the same operating conditions. It has been found that the new mixture can improve the actual COP by 2 to 13% and hence it can reduce the energy consumption by 20 to 31.5%. The overall performance has proved that the new refrigerant mixture could be a promising substitute for HCFC22.


2011 ◽  
Vol 7 (1) ◽  
Author(s):  
Jack Ethridge ◽  
Treba Marsh ◽  
Esther Bunn

Planning and conducting the audit of financial statements involves understanding the entity and the environment in which it operates.  First and foremost this requires identifying the risks faced by the entity.  Identifying these risks can be a complex and difficult task since the auditor needs to not only understand the entity’s risk process but also independently understand the risks facing the firm.  Tackling this task will involve a comprehensive review of the external and internal factors affecting the business.  It is possible many identified business risks are related to financial reporting risk and ultimately to audit risk.  Therefore, the auditor must understand the linkage between risks, controls and the audit.  The objective of this paper is to examine the risks faced by U.S. companies conducting business in China.  This paper attempts to identify a wide array of risks faced by U.S. companies to demonstrate how important it is for the company and the auditor to understand the business environment.


2021 ◽  
Vol 44 (1) ◽  
pp. 63-72
Author(s):  
D. Sh. Sharipov

The study of the processes occurring deep in the earth's crust has always been a relevant research topic. The results of these studies allowed development and safe mining of mineral deposits in various conditions. The growth in the consumption of extracted resource and the increase in the scale of mining are forcing enterprises to search for the solutions to complex engineering and technical problems, one of which is the problem of displacement of rock masses and the earth's surface in industrial production-affected areas including tailings dams. The purpose of this study is to improve the operation safety of tailing dams. The object of the study is embankment dams of dressing plant tailing dumps. The subject of the study is deformation processes occurring in dam bodies and slope surfaces. The main research methods used in the work are: the study of safe operation methods for tailing dams based on the operating conditions of Uchalinskoye tailing dump using the modern methods of stability assessment, analysis and generalization of domestic and foreign experience, as well as the study of current methods of geomechanical monitoring of deformation processes – engineering and geological, geophysical, mine surveying and hydrogeological ones. The article describes geographic, hydrographic, climatic, geological and mining operation conditions of the tailing dump of Uchalinsky GOK (Ore Mining and Processing Plant) JSC. The influence of hydrodynamic and hydrostatic forces on embankment tailing dam stability is substantiated. Based on the data obtained and the research methods used, it is concluded that hydrodynamic and hydrostatic forces are fundamental destructive factors affecting dams. The results of these studies can be applied at the design stage of hydraulic structures, since they will supplement theoretical knowledge about the impact of liquid waste on the safety of tailing dams and earth-filled dams, as well as allow detecting deformation processes at their initial development stage and making decisions on their elimination.


Author(s):  
Vladimir Bilik

A Rieke diagram [1] is a magnetron characteristic that visualizes the dependence of the generated frequency fg and the net delivered power PL on the load reflection coefficient GR. GR is defined in a specific magnetron-to-waveguide coupling structure called the standard or reference launcher (Fig. 1). The diagram is plotted as a family of isolines of constant fg and of constant PL in the polar diagram of GR. Rieke diagrams are essential in the design of applications without isolators, such as domestic or professional microwave ovens. Constructing Rieke diagrams is tedious, time-consuming and equipment-demanding [2], [3], preventing systematic studies of their dependence on operating conditions, such as anode voltage and its ripple, filament current, mounting repeatability, etc. We have devised a procedure, centering around a high-power automatic impedance matching device (autotuner), which enables fully automatic measurement and plotting of the stated dependences. A block diagram of the setup is shown in Fig. 1. The autotuner, when terminated in a match (waterload), can accomplish a task inverse to impedance matching: realizing any desired reflection coefficient GR. The measurement consists of stepping through a grid of n suitably chosen reflection coefficients GR = xR + jyR, covering a desired area of the polar diagram. Each GR is measured accurately by the autotuner, along with the corresponding fg and PL. Thus, raw data for constructing a Rieke diagram are obtained, the data consisting of a collection of n points {GR, fg, PL}i, i = 1…n, with GR, in general, irregularly scattered in the complex plane. A dedicated MATLAB routine then reads the data, sorts them out to create tabulated functions fg = f(xR, yR), PL = f(xR, yR), approximates these by a 2D spline, and uses the splines to plot smoothed isocontours for chosen constant values of fg and PL, completing thus the desired Rieke diagram construction. We will present details of this procedure as well as real-life examples. Fig. 1. Rieke diagram measurement setup. References Meredith, R. J., Engineers' Handbook of Industrial Microwave Heating, London: The IEE, 1998, 250–270. Takahashi, H., I. Namba, K. Akiyama, J. Microwave Power, 1979, 14, 261–267.Yixue, W., Z. Zhaotang, Proc. ICMMT'98, 1998, 795–798.


2011 ◽  
Vol 250-253 ◽  
pp. 3228-3231 ◽  
Author(s):  
Da Hua Jiang ◽  
An Gui Li ◽  
Fa En Shi ◽  
Zhi Hua Wang

For particular commercial kitchen, using CFD software to build model according to the actual operation condition uttermost, adopting the exhaust system of up-suction hood, the effect of exhaust airflow rate on working temperature,velocity,CO2 concentration at main site in commercial kitchen is studied. According to the common four calculation methods of airflow rate of exhaust hood, the simulation results shows 4.81 m3/s of exhaust system can realize eliminating harmful gas quickly and effectively, IAQ is good relatively. Based on of it, additional airflow rate can not improve emissions effect and operating conditions obviously, whereas it can be detrimental to save energy. The simulation results help design exhaust system.


2019 ◽  
Vol 135 ◽  
pp. 01034
Author(s):  
Vadim Bespalov ◽  
Gennadiy Turk ◽  
Oksana Gurova

The article is devoted to the study of the process of reducing air pollution in relation to the operating conditions of the drying drum of brick factories. The objectives of the work were to study and identify the physical characteristics of the process of reducing air pollution for the operating conditions of the drying drum of brick factories, for its subsequent effective implementation with the help of engineering systems. A block diagram is suggested of the physical model of the process of reducing air pollution for the considered production and technological conditions, revealing the relationship of a set of consistently and purposefully implemented stages of the cycle of dusting, using physical and energy concept as the theoretical basis. As a result of the study of the process of reducing air pollution, in relation to the operating conditions of the drying drum of brick factories operation, based on the analysis of possible solutions of the problem of dusting, physical features of the process of reducing air pollution for these production and technological conditions were identified for its subsequent effective implementation by means of engineering systems.


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