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The purpose of this paper is to investigate the performance of unpaced reliable production lines that are unbalanced in terms of their mean operation times, coefficients of variation and buffer capacities.

Simulations were carried out for five‐ and eight‐station lines with various buffer capacities and degrees of means imbalance. Throughput, idle time and average buffer level performance indicators were generated and statistically analysed.

The results show that an inverted bowl allocation of mean service times, combined with a bowl configuration for coefficients of variation and a decreasing order of buffer sizes results in higher throughput and lower idle times than a balanced line counterpart. In addition, considerable reductions in average inventory levels were consistently obtained when utilizing a configuration of progressively faster stations, coupled with a bowl‐shaped pattern for coefficients of variation and an ascending buffer size order.

The results for these specific experiments imply that resources expended on trying to achieve a balanced line could be better used by seizing upon possible enhanced performance via controlled mean time, variability and buffer imbalance. Results are valid for only the line type and parameter values used (simulation results are specific and not general).

Guidelines are provided on design strategies for allocating labour and capital unevenly in unpaced lines for better performance in terms of increased throughput or lowered idle time or average buffer levels.

This paper might be viewed as one of the first simulation investigations into the performance of unpaced production lines with three sources of imbalance.

The purpose of this paper is to investigate the performance of unpaced unreliable production lines that are deliberately unbalanced in terms of their coefficients of variation (CVs).

A series of simulation experiments were carried out for five and eight station lines with mean buffer space set at one, two, four and six units. CVs were allocated in 12 different configurations for each of these lines.

The results show that the best unbalanced CV patterns in terms of throughput rates or idle times as compared to a balanced line counterpart are those where the steadiest stations are concentrated near the centre of the line. On the other hand, either concentrating the steadier operators towards the centre or close to the end of the line gives best average buffer level results.

The results provide guidelines for production line managers when designing unpaced unbalanced lines depending on their performance aims.

The investigation of the effects of unbalancing CVs in unreliable lines has not previously been studied and can provide insights into how best to place workstations with differing variability along the line.

“It should also be noted that the objective of convergence and equal distribution, including across under-performing areas, can hinder efforts to generate growth. Contrariwise, the objective of competitiveness can exacerbate regional and social inequalities, by targeting efforts on zones of excellence where projects achieve greater returns (dynamic major cities, higher levels of general education, the most advanced projects, infrastructures with the heaviest traffic, and so on). If cohesion policy and the Lisbon Strategy come into conflict, it must be borne in mind that the former, for the moment, is founded on a rather more solid legal foundation than the latter” European Commission (2005, p. 9)Adaptation of Cohesion Policy to the Enlarged Europe and the Lisbon and Gothenburg Objectives.

Most of the European Mediterranean countries are suffering from seasonality and the problems caused by it. By applying different methods, this study proposes to measure seasonality in a Mediterranean country, Turkey. Studying seasonality and its measurement with the comparison of different methods could first provide useful guidelines for the countries, which may have similar problems, and could also broaden the current view in the related literature since the focus is also on the comparison of the widely used methods in the literature.

The study depends on the current literature and makes evaluations based on the secondary data acquired from the statistical publications of The Turkish Ministry of Culture and Tourism.

The findings reveal that none of the methods is superior to any other. They complement the weaknesses of one another. Therefore, it is suggested that destinations, when measuring their seasonality, should evaluate seasonality by applying different methods in order to give a proper decision to solve the problem caused by seasonality.

The study contributes to the seasonality literature by employing different measurement methods in a holistic way. It reveals differences and similarities among the different methods, using the case of a Mediterranean country, Turkey.

Structural sociological framework suggests that sociopolitical and economic factors exert independent effects on variations in family status attainment (FSA) across the social/ethnic groups. The purpose of this paper is to analyze and predict how social-political-economic factors exert effects on disparity in FSA between the majority and minority ethnic groups in Bangladesh.

This study used the cross-cultural survey design to analyze the research objective. In doing so, 585 men (Muslim n=150, Hindu n=145, Santal n=145, and Oraon n=145) who were randomly selected through cluster sampling from the Rasulpur union of Bangladesh were interviewed with a semi-structured questionnaire.

The results of Pearson’s χ² test have shown that FSA was significantly different (p<0.01) associated with social-political-economic factors between the majority and minority groups. The results of the linear regression analysis (coefficients of β) suggested that social, political, and economic factors were the best predictors (significant at p<0.01 level) to perpetuate disparity in FSA between the majority and minority ethnic groups in Bangladesh. In addition, the results of coefficients of determination (R²) suggested that unequal distribution of social-political-economic resources perpetuates 10-14 percent disparities in FSA between the majority and minority groups in Bangladesh.

Although the findings of the study are suggestive to understand the disparity in FSA associated with social-political-economic factors, further cross-cultural research is needed on how the social psychological factor affects variations in FSA between the groups in Bangladesh. In spite of the limitation, social policymakers may apply the findings with caution to design social policy and practice to reduce the disparity in FSA between the majority and minority ethnic groups in Bangladesh.

The cross-cultural findings are original in linking structural sociological theory and comparative family welfare policy to reduce the disparity in FSA between the majority and minority groups in Bangladesh.

The purpose of this paper is to apply a poverty level decomposition approach to decompose the poverty by income sources and investigate the impact of government transfers on income inequality and rural poverty.

This paper uses the decomposition method of inequality and the decomposition method of poverty level by resource endowments to decompose the overall inequality and the overall poverty by income sources.

It is found that unequal income distribution rather than income endowments is mainly responsible for the existence of poverty. Government transfers and relief income, aiming at the poor, help alleviate inequality and poverty, but are not targeting the poorest. Unequal distribution of production subsidies actually lead to higher poverty incidence.

This paper has revealed that the poverty issue cannot be resolved with economic development alone if the issues including the inequality in income distribution are not solved. It is important to make government transfers/subsidies pro-poor.

A poverty level decomposition approach is first used to decompose the poverty by income sources in China.

This chapter is aimed at proving that digital competition is widespread, and the unequal distribution of technologies in entrepreneurship leads to business conflicts. Official Russian and international statistical data for 2021 is used. The variation analysis method is used to reveal differences in the level of digital development of enterprises from various sectors of the Russian economy, as well as differences in the level of digital development of enterprises throughout the world. The contribution of this chapter to the literature consists of the development of the Conflict Theory through the identification of business conflicts in digital competition as a particular type of business conflict, which is characterized by an unequal distribution of technologies in entrepreneurship. The novel nature of the chapter lies in the fact that it has for the first time systematized the factors of unequal distribution of technologies in entrepreneurship. The authors’ classification of business conflicts in digital competition in entrepreneurship according to their determining factors has been put forward. The essence has been clarified and the cause-and-effect relations of business conflicts in digital competition in entrepreneurship have been identified. Recommendations have been developed for the management of business conflicts in digital competition in entrepreneurship, taking into account their peculiarities.

In‐plane vibration of a balanced helicopter rotor is caused by variations with azimuth of the in‐plane forces acting on individual blades. These forces may be summarized under three headings: ‘Induced forces’ caused by the inclination of elemental lift vectors relative to the axis of rotation. ‘Profile drag forces’: variations are caused by changes with azimuth angle of the angle and airspeed of the individual blade elements. ‘Coriolis forces’, which are caused by blade flapping, which brings about a variation of blade moment of inertia about the axis of rotation. Equations are developed in this paper for the resultant hub force due to each of these forces, on the assumptions of small flapping hinge offset. It is assumed that blades are linearly twisted and tapered, an assumption which in practice can be applied to any normal rotor. It is shown that by suitably inclining the mechanical axis it is possible to balance out the worst induced and profile drag vibrations by the coriolis one, which can be made to have opposite sign. If the mechanical axis is fixed in the fuselage, this suppression is fully effective for one flight condition only. In multi‐rotor helicopters, vibration suppression can be extended over a much wider range by varying the fuselage attitude. The logical result of this analysis is, for single rotor helicopters, a floating mechanical axis which can be adjusted or trimmed by the pilot. This would be quite simple to do on a tip‐driven rotor, and has already been achieved with a mechanical drive on the Doman helicopter. The more important causes of vibration from an unbalanced rotor are next con‐sidered, attention here being confined principally to fully articulated rotors, which are the most difficult to balance because the drag hinges tend to magnify all in‐accuracies in finish and balance. From a brief discussion of the vertical vibration of an imperfect rotor it is shown that some contemporary methods of ‘tracking’ are fundamentally wrong. Finally the vibration due to tip‐mounted power units is described. In discussing the effect of a vibratory force on a helicopter a simple response chart is developed, and it is thought that its use could well be accepted as a simple standard for general assessment purposes. In the development of equations for vibration the following points of general technical interest are put forward: An equation for induced torque is developed which includes a number of hitherto neglected parameters. A new form of equation for mean lift coefficient of a blade is suggested. The simple Hafner criterion for flight envelopes is shown to give rise to considerable error, and the use of Eq. (28) is suggested in its place. The variation of profile torque with forward speed is given, and the increase due to ? varying round the disk is expressed as an explicit equation, thus allowing considerable improvement in the present methods of allowing for this effect.

In this chapter, we seek to contribute to a line of international and comparative research that began with Heyneman and Loxley's 1983 study examining the importance of schools across national contexts. In their influential paper, Heyneman and Loxley found that in lower-income societies, schools (rather than families) constitute the predominant influence in explaining student achievement. Similar studies followed, often with results challenging Heyneman and Loxley's original findings. We argue that one reason for inconsistencies among these studies is the failure to account for the distribution of income. Until recently, few studies had examined whether school effects vary across countries with different levels of income inequality. Yet emerging evidence suggests that inequality plays an important role in determining the extent to which schools “matter” for student learning. In this study, we employ hierarchical linear modeling and two related yet distinct measures of inequality to examine how inequality relates to within- and between-country variations in student performance. We also explore whether, in certain countries, schools are differently able to help children from higher- and lower-Socio Economic Status (SES) groups. To capture sufficient variation in country context, we use data from nine diverse countries participating in the fourth grade application of the 2003 Trends in International Mathematics and Science Study (TIMSS). Our findings indicate that schools are important in their own right, and especially important in unequal countries. However, schools may affect SES-based achievement gaps only in countries with high income and resource inequality, accompanied by heterogeneous classrooms in terms of SES composition.

The purpose of this paper is to investigate the aerodynamics characteristics (especially the side force/moment and rolling characteristics), to analyze the impacts generated by different parameters of wrap-around fins (WAFs) and to find the corresponding mechanism.

The paper has adopted three different types of WAFs for the rocket configurations and the sub-regions divided technology to investigate the lateral and rolling characteristics of WAFs, including the fins with variations in span to chord ratio, thickness, leading-edge sweep, curvature radius, fin numbers, setting angles and rotated angles. Simulations have been performed at Mach numbers from 3 to 4 through an angle-of-attack range of about 0° to 10° and at model rolling angles of 45° to 90°.

The paper shows that the WAF configurations can greatly improve the longitudinal stability and enhance the longitudinal aerodynamic characteristics for the whole rocket. The total drag of the whole rocket is mainly stemmed from the body, while the drag generated by the WAF account for only about 7.42 per cent. The extra side forces and rolling moments are due largely to the unequal pressure distributions on both sides of the fin (windward or leeward). Maintaining a certain negative setting angle (d) can effectively avoid the coning movement and improve the flight stability at high angles of attack. The size of the span and chord are two main factors in controlling the longitudinal characteristics. For the side force/moment and rolling characteristics, different geometric parameters of the WAFs have played different roles.

The paper provides the qualitative and quantitative analysis for different WAFs configurations by investigating the curves of different parameters and contouring of static pressure distributions. Findings can provide some suggestions for the designers for avoiding some significant dynamic problems, such as Magnus instability and roll rate variations during flight.