Minimum Consumption Requirement Research Articles

Unmanned aerial vehicle location systems. Antenna Arrays

Radars remain the only all–weather location systems, which is especially important in difficult conditions of their use. Antenna array technologies remain critical for the development of dynamic areas of technology and, first of all, UAVs location systems. The development of location systems and antenna arrays for UAVs has been going on for a long time. Radars and antenna arrays installed on medium– and large–class UAVs differ little from airplane and helicopter systems. Among UAVs, the maximum number of UAVs used are UAVs of minimal size, weight and cost. Due to their high maneuverability, minimal visibility and a large number of tasks to be solved. Therefore, radars are subject to minimum size, weight, dimensions and consumption requirements at maximum range. The widespread use of small UAVs has led to the fact that their radars and antenna arrays are on a par with automotive ones, when the possibilities for their placement are significantly limited, even more so than in cars. For the latter, the problem of miniaturization appeared earlier, but not as severely as in UAVs. Antenna arrays are subject to requirements for minimizing dimensions, weight and consumption. Nanotechnology provides this. It's safe to say that the time has come for large–scale solutions to complex problems in antenna systems. Depending on the type of a UAV, it is possible to use a number of methods for constructing antenna arrays: known and proven – linear and fractal; the most modern – metastructures; widely used – tiled; new: flexible and three–dimensional printed; a combination of several methods. Currently, the most attractive areas for the development of antenna arrays for UAVs are: scaling – growing a large number of similar structures to create large apertures; spacing antenna arrays across the surface of the carrier for viewing both forward, sideways and backward, as well as down and up. The development of silicon tiled antenna arrays has led to the realization of very high operating frequencies (90–100 GHz) on the most affordable process technologies (130–180 nm), and the antenna array is fabricated as a chip. The optimal option for constructing antenna arrays is to ensure the reception, conversion and preprocessing of input signals directly in the antenna system in real time, unloading the radar for solving problems that require powerful processing. Post–processing allows you to obtain a more accurate solution to the problem. The combination of pre–processing and post–processing, supported by advanced software and powerful artificial intelligence, expands the capabilities and improves the parameters of the location system. It is important that artificial intelligence ensures the autonomous movement of a UAV, although its use requires large consumption and memory resources. The integrated location system absorbed for the most part the capabilities of a large stationary radar. At the same time, minimum dimensions, weight and consumption are ensured to solve the necessary modern problems. Several radars with their own antenna arrays can be installed on a UAV, which operate in the internal network, complementing each other.

Numerical simulation of formation optimization for a fleet of unmanned surface vehicles based on a minimum energy consumption requirement

This study proposes a hydrodynamic optimization strategy focusing on minimum energy consumption to construct the formation of a fleet of unmanned surface vehicles (USVs) by transforming the longitudinal offset and transverse separation. USVs were used instead of Autonomous Underwater Vehicles (AUVs) to fully consider the influence of a wave on energy-savings and to address undersize spacing and limited wake. The numerical model provided reasonably accurate results when compared against a series of experimental prototype results. The body force model was used to replicate the impact of the propeller, and an echelon formation was arranged considering the aft wedge wave pattern region induced by the Kelvin wave. The energy consumption equations of two-, three-, and four-hull formations were denoted by resistance components and used to determine the energy relationship between individuals and collectives. Additionally, an optimization platform was developed to integrate the application programs because the computation times were extensive for numerical simulations of spacing configurations transformation

Optimal Investment, Consumption, and Life Insurance Choices with Habit Formation and Inflation Risk

This research studies the optimal consumption, investment, and life insurance choices for a wage earner with habit formation, inflation risk, and mortality risk. The wage earner has access to a risk‐free asset, an index bond, and a stock in a financial market. The index bond hedges inflation risk, while life insurance hedges mortality risk. The aim of the wage earner is to maximize the expected utility of consumption, bequest, and terminal wealth, where the utility of consumption comes from the part of the consumption that exceeds a minimum consumption requirement given by the habit level. By using the dynamic programming method, we provide and prove a verification theorem and obtain closed‐form expressions for the value function, the optimal life insurance premium rate, and the optimal investment and consumption strategies. Numerical results reveal that habit formation and mortality force change play important roles in the financial behaviors of the wage earner. Especially, the impacts of the expected inflation rate and consumption habit on the optimal strategies are mutual restraint; increasing mortality force raises the demand for life insurance; and the effects of other parameters are also affected by consumption habit and mortality force change.

Design for Reliability Through Text Mining and Optimal Product Verification and Validation Planning

Failure mode and effects analysis (FMEA) has been widely used in product design process as a reliability analysis technique. Design FMEA (DFMEA), which is used in the product development phase to identify and mitigate product risk, is one of the three application scenarios of FMEA. During the DFMEA process, verification and validation (V&V) activities are proposed to mitigate the risk of the identified potential failure modes. The V&V activities can be further planned and implemented to improve the product reliability under development. However, the DFMEA report usually contains rich text descriptions of potential failure modes and causes, and it is difficult and nonintuitive to fully understand these information for design improvements. In addition, it is also very challenging to optimize the planning of V&V activities by selecting a set of V&V activities to achieve expected reliability improvement effectiveness with the minimum resource consumption requirement. To address these two challenges, this article first proposes a method of applying text mining to the DFMEA report to obtain two types of hidden reliability information, including the classifications of failure modes/causes and the correlation between keywords. Then, a mathematical model is proposed to optimize the product V&V planning by selecting an optimal set of V&V activities. The application of the above proposed methods is illustrated through the product development of a diesel engine power generation system.

Income and greenhouse gas (GHG) emission trade-offs on smallholder farms at two sites in northern Nigeria

This study analyses the trade-offs between welfare (measured by income) and greenhouse gas (GHG) emissions using a farm-level optimisation model that incorporates the predominant cereal (sorghum), legumes (groundnut, soybeans), livestock (cattle, goats and sheep) and trees (locust bean, camel’s foot) representative of production systems at two contrasting sites in northern Nigeria. The optimisation model maximises the value of total farm production, subject to constraints on GHG reductions of 10%, 25% and the maximum reductions that allow households to meet minimum consumption requirements. Substantive reductions in livestock and legume production would be required to achieve the maximum possible reductions from current emissions and would reduce household income by 22% and 44%, respectively. Under current production practices, reductions in GHG emissions reduce household income, which suggests the need for further research on productivity-enhancing technologies that could both enhance income and reduce GHG emissions in these production contexts.

Occupational Variation in Quantity–Quality Trade-off in a Brawn-Based Economy

The paper revisits the theory of the quantity–quality trade-off and demonstrates that the relationship between quantity and health of children is subject to occupational variation in physical energy requirements. It embeds, in a simple household optimisation model, a minimum consumption requirement that rises with physical work intensity of occupation. Occupational differences in minimum consumption requirement generates variation in child nutritional status – the shadow price of quantity, which in turn generates varying quantity–quality relationships. The model yields an equilibrium relationship between the number and nutritional status of children that is positive for households in strenuous occupations and ambiguous for other households. A numerical example using a calibrated model illustrates that these trade-offs are consistent with the phenomenon of intergenerational persistence of nutritional status. These new insights into the nature of the quantity-quality trade-off help reconcile some inconsistent empirical findings on such trade-offs.

Occupational variation in the relationship between child health and family size.

Empirical evidence for quantity-quality trade-off is hardly ubiquitous, especially when quality is measured by child health outcomes. The paper offers a new explanation to this puzzle. It shows that the quantity-quality relationships are subject to occupational variation when quality is given by nutritional status, and occupations differ in their physical labor intensity. It embeds, in a simple household optimization model, a minimum consumption requirement that rises with physical work intensity of occupation. The occupational differences in subsistence consumption requirement generate variation in child nutritional status, and hence, in the shadow price of children. The nature of the quantity-quality relationship, therefore, varies with work intensity of occupations. The model yields an equilibrium relationship between the number and nutritional status of children that is positive for households in strenuous occupations and ambiguous for other households. These results help reconcile some inconsistent findings on quantity-quality trade-off, which may partly be explained by the omission of occupational variation in nutritional status.

The human rights foundations of an EKC with a minimum consumption requirement: theory, implications, and quantitative findings

Andreoni and Levinson’s (J Public Econ 80:269–286, 2001) EKC model is modified to include Stone (Econ J 63:511–527, 1954) and Geary (Rev Econ Stud 18(99):65–66, 1950) preferences where the economic agent has a minimum consumption requirement (MCR). We show that at each level of income, an increase in the MCR is associated with higher levels of pollution, and the threshold level of income at which the EKC inverts changes with a change in the MCR. A numerical exercise further supports these findings. We offer a policy discussion within the context of the environmental impacts of meeting a MCR noting that doing so is costly in terms of the impact on pollution and the resources required to mitigate pollution in its presence.

Agriculture, Aid, and Economic Growth in Africa.

How can foreign aid to agriculture support economic growth in Africa? This paper constructs a geographically indexed applied general equilibrium model that considers pathways through which aid might affect growth and structural transformation of labor markets in the context of soil nutrient variation, minimum subsistence consumption requirements, domestic transport costs, labor mobility, and constraints to self-financing of agricultural inputs.Using plausible parameters, the model is presented for Uganda as an illustrative case.We present three stylized scenarios to demonstrate the potential economy-wide impacts of both soil nutrient loss and replenishment, and how foreign aid can be targeted to support agricultural inputs that boost rural productivity and shift labor to boost real wages. One simulation shows how a temporary program of targeted official development assistance (ODA) for agriculture could generate, contrary to traditional Dutch disease concerns, an expansion in the primary tradable sector and positive permanent productivity and welfare effects, leading to a steady decline in the need for complementary ODA for budget support.

Energy Aware Routing Algorithm in Manet Using Linear Programming

Mobile ad hoc networks (MANET) are wireless network without infrastructure and suffering from low power battery. Therefore the main objective in finding a route for traffic transfer from a given source to a given destination is to minimize the node energy consumption. This paper solves the problem of finding a route satisfying the main objective of minimum energy consumption and other QoS requirements such as minimum delay and maximum packet delivery ratio by using linear programming technique. Two cases are considered: 1. The traffic amount of a given request is transmitted into single path, and 2. The traffic amount of a request can be distributed into parallel paths. A preprocessing step is done first for network topology design. This step leads to formulate the first case as integer linear programming problem and the second case as linear programming and not mixed integer linear programming. The two obtained solutions are evaluated in terms of three criteria: energy consumption, execution time, and packet delivery ratio using an experimental study. The results show that the solution of second case is much better than the first case in terms of energy consumption and execution time. Packet delivery ratio in the second case is 100% while in the first case is only 76%.

Demand-Based Structural Change and Balanced Economic Growth

We analyze the equilibrium of a multi-sector exogenous growth model where the introduction of minimum consumption requirements drives structural change. We show that equilibrium dynamics simultaneously exhibit structural change and balanced growth of aggregate variables as is observed in US when the initial intensity of minimum consumption requirements is sufficiently small. This intensity is measured by the ratio between the aggregate value of the minimum consumption requirements and GDP and, therefore, it is inversely related with the level of economic development. Initially rich economies benefit from an initially low intensity of the minimum consumption requirements and, as a consequence, these economies end up exhibiting balanced growth of aggregate variables, while there is structural change. In contrast, initially poor economies suffer from an initially large intensity of the minimum consumption requirements, which makes the growth of the aggregate variables unbalanced during a very large period. These economies may never exhibit simultaneously balanced growth of aggregate variables and structural change.

Demand-based structural change and balanced economic growth

We analyze the equilibrium of a multi-sector exogenous growth model where the introduction of minimum consumption requirements drives structural change. We show that equilibrium dynamics simultaneously exhibit structural change and balanced growth of aggregate variables as is observed in US when the initial intensity of minimum consumption requirements is sufficiently small. This intensity is measured by the ratio between the aggregate value of the minimum consumption requirements and GDP and, therefore, it is inversely related with the level of economic development. Initially rich economies benefit from an initially low intensity of the minimum consumption requirements and, as a consequence, these economies end up exhibiting balanced growth of aggregate variables, while there is structural change. In contrast, initially poor economies suffer from an initially large intensity of the minimum consumption requirements, which makes the growth of the aggregate variables unbalanced during a very large period. These economies may never exhibit simultaneously balanced growth of aggregate variables and structural change.

A General Equilibrium Model for Analyzing African Rural Subsistence Economies and an African Green Revolution

How can foreign aid support economic growth in Africa? This paper presents a geographically indexed general equilibrium model that enables green revolution-focused macroeconomic analysis in low-income African settings. The model is flexible to parameterization and highlights the role of farmers’ constraints to self-financing of inputs alongside minimum subsistence consumption requirements. It includes particular attention to the challenge of soil productivity and to the effects of official development assistance (ODA) for agricultural inputs and road building. Uganda is used as an illustrative case. The economy’s labor force is predominantly still located in rural areas and remains overwhelmingly focused on staple food production. Under plausible economy-wide parameters, a foreign-financed green revolution package shows a clear anti-Dutch disease result, in which the temporary boost in targeted ODA yields permanent productivity and welfare effects at relatively low cost.

On the Natural and Economic Difficulties to Fulfilling the Human Right to Water Within a Neoclassical Economics Framework

We present a neoclassical economic model of the human right to water using a nonrenewable resource model inclusive of a backstop technology. The right is interpreted as a minimum consumption requirement the government is obligated to fulfill in the event that any one household cannot do so independently. Differing by income levels, households maximize utility by purchasing a composite consumption good and water from two distinct, government-owned sources. Facing physical and financial constraints, the government uses fiscal policy to address potential human rights violations. Reducing the analysis to two periods, we develop a novel approach to compare total welfare levels from a joint human rights and neoclassical economics perspective. We define a human rights welfare standard and discuss cases in which traditional social welfare measures would exceed, violate, or meet this standard. We thus offer a unique way to merge economic analysis with human rights research.

Land-use changes, forest/soil conditions and carbon sequestration dynamics: A bio-economic model at watershed level in Nepal

A dynamic bio-economic model has been used at watershed level in Nepal to analyze the land-use changes, forest and soil conditions and their resultant impacts on carbon (C) sequestration. Planning horizon of the model extends over a period of 25 years. The objective function is maximization of the sum of discounted net income flows from agriculture, livestock and forestry productions; imputed value of leisure and labour hiring out activities subject to annual constraints on land, labour and capital availability along with the fulfilment of minimum cash and consumption requirements. The seven scenarios analyzed by the model are: business as usual (BAU), reduction in population growth rate from 2 to 1.5% p.a., increased prices of major crops by 10 and 20%, reduction in emigration of active labour force from the watershed from the current rate of 20–15 and 10%, and increase in discount rate from 5 to 10%. The results indicate that reduced labour emigration rates and increase in the prices of major crops lead to expansion of cultivated area and shift from one land use to the others. Land clearing becomes more severe with decline in labour emigration rate. Up to 10% increase in the prices of agricultural crops does not have noticeable effect on total land clearing. Increase in discount rate leads to less land clearing, more biomass harvesting and higher net C sequestration as compared to the BAU scenario. Assuming a C price of 10 USD per MgC and 5% discount rate, the net present value of C sequestration for the first 25 years is estimated at 1.83 mill USD in the BAU scenario, varying from 0.16 mill USD to 2.26 mill USD, as respectively the lowest and highest values for the seven scenarios analysed. A reduction in population growth and maintenance of current rate of off-farm employment are suggested for slowing down the expansion of cultivated land area, and thereby reducing the forest/soil degradation and C emissions. This in turn would enhance the income potential from C sequestration.

The Dynamic Implications of Debt Relief for Low-Income Countries

The effects of debt relief on incentives to accumulate debt, consume, and invest are an important concern for donors and recipients. Using a dynamic stochastic general equilibrium model of a small open economy with a minimum consumption requirement and an endogenous relief probability, we show that excessive debt accumulation is consistent with an anticipation of a future debt relief. Simulations of the calibrated model using 1982-2006 Ugandan data suggest that debt-relief episodes are likely to have only a temporary impact on the level of debt in low-income countries, while being associated with more consumption and less invesment. The long-run debt-to-GDP ratio is estimated to be about twice as high with debt relief than without it.

The Dynamic Implications of Debt Relief for Low-Income Countries

The effects of debt relief on incentives to accumulate debt, consume, and invest are an important concern for donors and recipients. Using a dynamic stochastic general equilibrium model of a small open economy with a minimum consumption requirement and an endogenous relief probability, we show that excessive debt accumulation is consistent with an anticipation of a future debt relief. Simulations of the calibrated model using 1982-2006 Ugandan data suggest that debt-relief episodes are likely to have only a temporary impact on the level of debt in low-income countries, while being associated with more consumption and less invesment. The long-run debt-to-GDP ratio is estimated to be about twice as high with debt relief than without it.

Comparison of optimal portfolios with and without subsistence consumption constraints

We present the effects of the subsistence consumption constraints on a portfolio selection problem for an agent who is free to choose when to retire with a constant relative risk aversion (CRRA) utility function. By comparing the previous studies with and without the constraints expressed by the minimum consumption requirement, the changes of a retirement wealth level and the amount of money invested in the risky asset are derived explicitly. As a result, the subsistence constraints always lead to lower retirement wealth level but do not always induce less investment in the risky asset. This implies that even though the agent who has a restriction on consumption retires with lower wealth level, she invests more money near the retirement when her risk aversion lies inside a certain range.

Growth, sectoral composition, and the evolution of income levels

We assert that the endowments of production factors cause cross-country differences in GDP by generating disparities in the sectoral composition. We characterize the dynamic equilibrium of a two-sector endogenous growth model with several consumption goods that are subject to minimum consumption requirements. In this model, economies with the same fundamentals but different endowments of capitals will end up growing at a common rate, although the long run sectoral composition of GDP will be different. Because the total factor productivity (TFP) in multisector models depends on sectoral structure, these differences in capital endowments will also generate sustained differences in TFPs.

Resurrecting equilibria through cycles in an overlapping generations model of money

Momentary equilibria are defined as points that satisfy agents’ optimality conditions and market clearing at any date. However, some dynamic sequences commencing from such points may not be considered valid equilibria because they asymptotically violate some economic restriction of the model. This paper studies a pure-exchange monetary overlapping generations economy in which young and old agents face exogenous minimum consumption requirements, and money is the only asset. The presence of the minimum consumption requirement on the old is shown to produce multiperiodic monetary equilibria in which real balances cycle forever between “momentary” equilibrium points (those which generate monetary sequences that potentially violate equilibrium strictures asymptotically). The novelty is to show that segments of the intergenerational offer curve that would have been deemed dynamically invalid can, in fact, be used to produce asymptotically valid cyclical paths. Indeed, a limit cycle can bestow dynamic validity on momentary equilibrium points that had erstwhile been classified as dynamically invalid.