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Book part
Publication date: 4 July 2019

Aleksei V. Bogoviz, Tatiana V. Skryl, Larisa A. Kapustyan, Ksenia V. Ekimova and Julia V. Ragulina

The purpose of the chapter is to consider the methodology of studying socio-economic systems through the prism of the theory of cycles and to analyze applicability of this…

Abstract

Purpose

The purpose of the chapter is to consider the methodology of studying socio-economic systems through the prism of the theory of cycles and to analyze applicability of this methodology to studying economic.

Methodology

Based on the dynamic model of development of socio-economic system through the prism of the theory of cycles, the authors analyze dynamics of development of Russia’s socio-economic system through the prism of the theory of cycles in 2000–2022.

Conclusions

Drawbacks of the existing theory of cycles are determined. First, the models of economic cycles are too idealized and are alien to the current economic reality. These models do not correctly describe cyclic fluctuations of modern socio-economic systems – which is shown by the example of Russia. Second, application of the methodology of the theory of cycles in practice (by the example of Russia) leads to contradictory results. Each indicator of economic growth, including investments into economy, inflation, unemployment level, and balance of federal budget, has its own cyclic fluctuations, which could differ from fluctuations of GDP in constant prices. Third, the system of factors of cyclic fluctuations of socio-economic systems includes primarily economic (not social) factors. Due to this, the theory of cycles takes into account only objective reasons of crises of socio-economic systems.

Originality/value

It is determined that domination of subjective reasons in emergence of economic conflicts makes application of the theory of cycles not applicable to full-scale study of economic conflicts – application of this concept is expedient only as to economic crises that are one of a lot of manifestations of economic conflicts. It is probably that neglecting subjective (social) factors leads to the above contradictions of the theory of cycles and difference between its theoretical models and empirical data. Based on this conclusion, it is substantiated that methodology of studying socio-economic system through the prism of the theory of cycles is not applicable to economic conflicts; it is determined that development of the concept of economic conflicts can specify and improve the methodology of the theory of cycles.

Article
Publication date: 7 March 2016

Zhiming Ma, Tiejun Zhao, Jianzhuang Xiao and Ting Guan

Rebar corrosion in reinforced concrete is the major reason for the durability degradation, especially under harsh environment. This paper presents an experiment conducted to…

Abstract

Purpose

Rebar corrosion in reinforced concrete is the major reason for the durability degradation, especially under harsh environment. This paper presents an experiment conducted to investigate the influence of freeze-thaw cycles on the rebar corrosion in reinforced concrete. The purpose of this paper is to provide fundamental information about rebar corrosion under frost environment and improvement measures.

Design/methodology/approach

The related elastic modulus and compressive strength of different concrete specimens were measured after different freeze-thaw cycles. The accelerated rebar corrosion test was carried out after different freeze-thaw cycles; additionally, the value of calomel half-cell potential was determined. The actual rebar corrosion appearance was checked to prove the accuracy of the results of calomel half-cell potential.

Findings

The results show that frost damage aggravates the rebar corrosion rate and degree under freeze-thaw environment; furthermore, the results become more obvious with the freeze-thaw cycles increasing. Mixing the air-entrained agent into fresh concrete to prepare air-entrained concrete, increasing the cover thickness and processing the surface of concrete with a waterproofing agent can significantly improve the resistance to rebar corrosion. From the actual appearance of rebar corrosion, the results of calomel half-cell potential can well reflect the actual rebar corrosion in reinforced concrete.

Originality/value

The durability of reinforced concrete is mainly determined on chloride penetration that brings about rebar corrosion in chloride environments. Furthermore, the degradation of concrete durability becomes more serious in the harsh environment. As the concrete exposure to the freeze-thaw cycles environment, the freeze-thaw cycles accelerate the concrete damage, and the penetration of chloride into the concrete becomes easier because of the growing pore and crack sizes. In addition, rebar corrosion caused by chloride is one of the major forms of environmental attack on reinforced concrete. The tests conducted in this paper will describe the rebar corrosion in reinforced concrete under freeze-thaw environment.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 January 2014

Vahideh Sadat Sadeghi and Hossein Miar Naimi

The linear analysis presented for the charge pump phase locked loops (CPPLLs) becomes inaccurate or incorrect where cycle slipping occurs. In this paper, an analytical approach is…

Abstract

Purpose

The linear analysis presented for the charge pump phase locked loops (CPPLLs) becomes inaccurate or incorrect where cycle slipping occurs. In this paper, an analytical approach is proposed, which explains the conditions in which cycle slipping happens. Using the analytical results, one can simply design or redesign a CPPLL to prevent or decrease cycle slipping and hence decreasing the locking time. The paper aims to discuss these issues.

Design/methodology/approach

To obtain cycle slipping conditions, CPPLL's signals in the time domain are tracked and cycle slipping condition is investigated. Based on the proposed analysis, by comparing a simple function of system's parameters with a threshold, cycle slipping is predicted.

Findings

The cycle slipping conditions are expressed in terms of system's parameters and the size of the input frequency step. The method is also generalized for a fast CPPLL with an aid-lock BBFC circuit. The good accuracy of the analytical predictions is verified using simulations in Matlab/Simulink.

Originality/value

A new analytical method for cycle slipping prediction in CPPLLs is presented. A closed form equation in terms of system's parameters and input frequency step has been presented, which can predict the cycle slipping possibility in the system without a need to perform the full time-consuming simulations. This analytical method that uses the LambertW function's properties proposes a threshold to predict cycle slipping in the system. This method not only can be used by designers to predict cycle slipping but can also be used to design the CPPLL in order to remove or decrease cycle slipping. The method is also generalized for fast locking charge pump PLLs and as a case study, cycle slipping prediction in the BBFC-CPPLL is performed.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 33 no. 1/2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 January 1990

J. Seyyedi and S. Jawaid

The wearout characteristics were investigated for soldered interconnections of surface mount technology (SMT) chip resistors, chip capacitors and a 44 I/O ceramic leaded chip…

Abstract

The wearout characteristics were investigated for soldered interconnections of surface mount technology (SMT) chip resistors, chip capacitors and a 44 I/O ceramic leaded chip carrier (CLCC) package. Four double‐sided test vehicles were subjected to accelerated thermal cycling in the — 10°C to + 110°C range; 30°C/min ramp rate; and 1 minute dwell time at each temperature extreme. The test was interrupted at initially 500 cycle and later at 1000 cycle intervals to perform visual inspection of all soldered interconnections, functional performance verification for the test vehicles, and resistance measurement on leaded SMT joints. Metallographic examinations and fractographic studies were also performed after 0, 4500 and 13000 cycles to characterise the micromechanisms of soldered joint strength degradation and failure. The wearout thresholds for soldered joints of chip resistors and capacitors on side 1 were respectively 2500 and 4500 cycles. The greater thermal fatigue resistance of the latter joints was attributed to a lower device‐substrate coefficient of thermal expansion (CTE) mismatch and a more favourable device geometry compared with chip resistors. These passive components on side 2, however, showed a virtually identical soldered joint wearout threshold of 6500 cycles. The constraints imposed by the applied mounting adhesive were primarily responsible for this behaviour. No correlation appeared to exist among various failure criteria used to determine the onset of failure for leaded SMT soldered connections. The concurrent monitoring of electrical resistance and the applied tensile load showed a modest relationship between the load drop and resistance increase, however. The test vehicles continued to pass the functional performance verification, even after 13000 thermal cycles. Nonetheless, the joint wearout thresholds were considered to be 2500, 4500 and 4500 cycles for chip resistor, chip capacitor and CLCC components, respectively. A 50% soldered joint strength drop was considered as the wearout threshold for the CLCC device. Metallographic examination showed limited barrel wall cracking of the vias and no evidence of cracks with the through‐hole soldered joints, even after 13000 thermal cycles.

Details

Soldering & Surface Mount Technology, vol. 2 no. 1
Type: Research Article
ISSN: 0954-0911

Article
Publication date: 1 February 2003

A. Kaveh and G.R. Roosta

An improvement is presented for the existing minimal cycle basis selection algorithms increasing their efficiency. This consists of reducing the number of cycles to be considered…

Abstract

An improvement is presented for the existing minimal cycle basis selection algorithms increasing their efficiency. This consists of reducing the number of cycles to be considered as candidates for being the elements of a minimal cycle basis and makes practical use of the Greedy algorithm feasible. A modification is also included to form suboptimal‐minimal cycle bases in place of minimal bases. An efficient algorithm is developed to form suboptimal cycle bases of graphs, in which the Greedy algorithm is applied twice. First a suboptimal minimal cycle basis is formed, and then ignoring the minimality, a basis with elements having smaller overlaps is selected.

Details

Engineering Computations, vol. 20 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 April 1990

George Norman

Defines life cycle costing, which gives rise to Life Cycle Cost(LCC). Defines LCC as “The total cost of the system or productunder study over its complete life cycle or the…

5367

Abstract

Defines life cycle costing, which gives rise to Life Cycle Cost (LCC). Defines LCC as “The total cost of the system or product under study over its complete life cycle or the duration of the period of study, whichever is the shorter”. Stresses that LCC can be used at whatever level is chosen (estate or, say, a boiler). Explains the timing and mechanism of measurement. Argues that the application of LCC at an early design stage will greatly enhance system design and operation. Offers other pertinent definitions.

Details

Property Management, vol. 8 no. 4
Type: Research Article
ISSN: 0263-7472

Keywords

Article
Publication date: 1 June 2010

A. Kaveh and M. Daei

Cycle bases of graphs have many applications in science and engineering. For an efficient force method of structural analysis, a special cycle basis corresponding to sparse cycle

Abstract

Purpose

Cycle bases of graphs have many applications in science and engineering. For an efficient force method of structural analysis, a special cycle basis corresponding to sparse cycle adjacency matrix is required. The purpose of this paper is to develop an ant colony system (ACS) algorithm for the generation of a cycle basis, leading to suboptimal cycle bases.

Design/methodology/approach

In this paper, an ACS algorithm is developed for the generation of a cycle basis, leading to suboptimal cycle basis corresponding to highly sparse flexibility matrices. Examples are included to illustrate the efficiency of the developed algorithm.

Findings

A new approach is developed which uses the recently developed ACS algorithm for the optimization.

Originality/value

Previously, graph theoretical method had been used for the formation of suboptimal cycle bases. Here, optimization is performed using ACS algorithm for the first time.

Details

Engineering Computations, vol. 27 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 February 1997

Lisa Michelle Grantham

Posits that, as the pace of change has accelerated rapidly and created unprecedented uncertainty in the markets of this decade, many companies have needed to dispense with…

17014

Abstract

Posits that, as the pace of change has accelerated rapidly and created unprecedented uncertainty in the markets of this decade, many companies have needed to dispense with existing, once reliable, practices in order to remain competitive. Suggests that the efficacy of one particular marketing tool, the product life cycle model, has been questioned, by various writers in the academic and business press, with regard to the general applicability and validity of its assertions and the claim it makes to be able to predict the marketing strategies that should be applied at different stages of a product’s life. Explores the arguments for and against the validity of the product life cycle model as a marketing tool in this present, dynamic environment.

Details

Marketing Intelligence & Planning, vol. 15 no. 1
Type: Research Article
ISSN: 0263-4503

Keywords

Abstract

Details

Nonlinear Time Series Analysis of Business Cycles
Type: Book
ISBN: 978-0-44451-838-5

Book part
Publication date: 20 June 2017

David Shinar

Abstract

Details

Traffic Safety and Human Behavior
Type: Book
ISBN: 978-1-78635-222-4

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