Leaky Bucket Research Articles

Pre‐reparations Preparation: Fixing the Plumbing before Turning on the Tap

ABSTRACTA growing number of communities in the global African diaspora are campaigning for reparations for historical and contemporary human rights violations. While the political advocacy campaigns continue, communities which are set to receive reparations should, through a process called pre‐reparations preparation, consider their current economic situation and how they may improve their circumstances with the restitution that they will receive. An integral part of pre‐reparations preparation is investigating community income and expenditure. This article explores the use of the leaky bucket analogy in assessing the Black American community's financial inflows and outflows, how Black communities can use this process to plan pre‐ and post‐payment community economic development, and why government administrators and regulators should engage in their own pre‐reparations preparation.

How to Address a Leaky Membership Bucket

How to Address a Leaky Membership Bucket

Synergism of Fuzzy Leaky Bucket with Virtual Buffer for Large Scale Social Driven Energy Allocation in Emergencies in Smart City Zones

Smart cities can be viewed as expansive systems that optimize operational quality and deliver a range of services, particularly in the realm of energy management. Identifying energy zones within smart cities marks an initial step towards ensuring equitable energy distribution driven by factors beyond energy considerations. This study introduces a socially oriented methodology for energy allocation during emergencies, implemented at the zone level to address justice concerns. The proposed method integrates a fuzzy leaky bucket model with an energy virtual buffer, leveraging extensive data from diverse city zones to allocate energy resources during emergent situations. By employing fuzzy sets and rules, the leaky bucket mechanism distributes buffered energy to zones, aiming to maximize energy utilization while promoting social justice principles. Evaluation of the approach utilizes consumption data from simulated smart city zones during energy-constrained emergencies, comparing it against a uniform allocation method. Results demonstrate the socially equitable allocation facilitated by the proposed methodology.

Quantifying Okun's Leaky Bucket: The Case of Progressive Childcare Subsidies

Quantifying Okun's Leaky Bucket: The Case of Progressive Childcare Subsidies

Surging of a Hudson Strait-scale ice stream: subglacial hydrology matters but the process details mostly do not

Abstract. While subglacial hydrology is known to play a role in glacial dynamics on sub-annual to decadal scales, it remains unclear whether subglacial hydrology plays a critical role in ice sheet evolution on centennial or longer timescales. Furthermore, several drainage systems have been inferred, but it is unclear which is most applicable at the continental/glacial scale. More fundamentally, it is even unclear if the structural choice of subglacial hydrology truly matters for this context. Here we compare the contribution to the surge behaviour of an idealized Hudson Strait-like ice stream from three subglacial hydrology systems. We use the newly updated BAsal Hydrology Model – BrAHMs2.0 – and provide model verification tests. BrAHMs2.0 incorporates two process-based representations of inefficient drainage dominant in the literature (linked cavity and poro-elastic) and a non-mass-conserving zero-dimensional form (herein termed leaky bucket) coupled to an ice sheet systems model (the Glacial Systems Model, GSM). The linked-cavity and poro-elastic configurations include an efficient drainage scheme while the leaky bucket does not. All three systems have a positive feedback on ice velocity, whereby faster basal velocities increase melt supply. The poro-elastic and leaky-bucket systems have diagnostic effective pressure relationships – only the linked-cavity system has an additional negative feedback, whereby faster basal ice velocities increase the dynamical effective pressure due to higher cavity opening rates. We examine the contribution of mass transport, efficient drainage, and the linked-cavity negative feedback to surging. We also assess the likely bounds on poorly constrained subglacial hydrology parameters and adopt an ensemble approach to study their impact and interactions within those bounds. We find that subglacial hydrology is an important system inductance for realistic ice stream surging but that the three formulations all exhibit similar surge behaviour within parametric uncertainties. Even a detail as fundamental as mass-conserving transport of subglacial water is not necessary for simulating a full range of surge frequency and amplitude. However, one difference is apparent: the combined positive and negative feedbacks of the linked-cavity system yield longer duration surges and a broader range of effective pressures than its poro-elastic and leaky-bucket counterparts.

The Leaky Bucket: Transition Costs from Cash to Deposits in a Mexican Transfer Program

The Leaky Bucket: Transition Costs from Cash to Deposits in a Mexican Transfer Program

Structural basis of the protochromic green/red photocycle of the chromatic acclimation sensor RcaE

Cyanobacteriochromes (CBCRs) are bilin-binding photosensors of the phytochrome superfamily that show remarkable spectral diversity. The green/red CBCR subfamily is important for regulating chromatic acclimation of photosynthetic antenna in cyanobacteria and is applied for optogenetic control of gene expression in synthetic biology. It is suggested that the absorption change of this subfamily is caused by the bilin C15-Z/C15-E photoisomerization and a subsequent change in the bilin protonation state. However, structural information and direct evidence of the bilin protonation state are lacking. Here, we report a high-resolution (1.63Å) crystal structure of the bilin-binding domain of the chromatic acclimation sensor RcaE in the red-absorbing photoproduct state. The bilin is buried within a "bucket" consisting of hydrophobic residues, in which the bilin configuration/conformation is C5-Z,syn/C10-Z,syn/C15-E,syn with the A- through C-rings coplanar and the D-ring tilted. Three pyrrole nitrogens of the A- through C-rings are covered in the α-face with a hydrophobic lid of Leu249 influencing the bilin pKa, whereas they are directly hydrogen bonded in the β-face with the carboxyl group of Glu217. Glu217 is further connected to a cluster of waters forming a hole in the bucket, which are in exchange with solvent waters in molecular dynamics simulation. We propose that the "leaky bucket" structure functions as a proton exit/influx pathway upon photoconversion. NMR analysis demonstrated that the four pyrrole nitrogen atoms are indeed fully protonated in the red-absorbing state, but one of them, most likely the B-ring nitrogen, is deprotonated in the green-absorbing state. These findings deepen our understanding of the diverse spectral tuning mechanisms present in CBCRs.

A proposed Ghanaian intercity public transport departure scheduling model based on the dynamic rate leaky bucket algorithm

In this paper, the random departure of intercity public transport buses in Ghana which is influenced by the arrival patterns of passengers is shaped into a deterministic one with regular departure intervals based on the dynamic rate leaky bucket algorithm. This is essential because a regulated bus departure system is capable of providing transit information to travellers thereby reducing passenger waiting times. The arrival patterns of passengers were simulated and grouped into three blocks based on the frequency of arrival of passengers. The three blocks represented peak seasons, moderate seasons and off-peak seasons. Departure intervals were then calculated to suit each block. The recommended fleet size required to maintain the departure consistency was also determined based on the fixed departure interval and the round-trip time. The second phase involved developing a bus schedule based on the determined fixed departure intervals and recommended fleet size. The results as depicted with graphs showed that the fixed departure schedule reduced passenger waiting times. The minimum fleet size could also give transit operators an idea of how to manage their fleet to efficiently use resources. The KNUST Campus shuttle was used as a test case for the model. A fixed departure schedule was developed based on the proposed model. Simulation results showed a significant reduction in passenger waiting times for various passenger arrival patterns and also proposed a recommended fleet size and bus capacity.

Implementation of Snowpack Treatment in the CPC Water Balance Model and Its Impact on Drought Assessment

AbstractDroughts are a worldwide concern, thus assessment efforts are conducted by many centers around the world, mainly through simple drought indices which usually neglect important hydrometeorological processes or require variables available only from complex Land Surface Models (LSMs). The U.S. Climate Prediction Center (CPC) uses the Leaky Bucket (LB) water-balance model to post-process temperature and precipitation, providing soil moisture (SM) anomalies to assess drought conditions. However, despite its crucial role in the water cycle, snowpack has been neglected by LB and most drought indices.Taking advantage of the high-quality snow water equivalent (SWE) data from the University of Arizona (UA), a single-layer snow scheme, forced by daily temperature and precipitation only, is developed for LB implementation and tested with two independent forcing datasets. Compared against the UA and SNOTEL SWE data over CONUS, LB outperforms a sophisticated LSM (Noah/NLDAS-2), with the median LB vs SNOTEL correlation (RMSE) about 40% (26%) higher (lower) than that from Noah/NLDAS-2, with only slight differences due to different forcing datasets.The changes in the temporal variability of SM due to the snowpack treatment lead to improved temporal and spatial distribution of drought conditions in the LB simulations compared to the reference U.S. Drought Monitor maps, highlighting the importance of snowpack inclusion in drought assessment. The simplicity but reasonable reliability of the LB with snowpack treatment makes it suitable for drought monitoring and forecasting in both snow-covered and snow-free areas, while only requiring precipitation and temperature data (markedly less than other water-balance-based indices).

Transfers, Income Increments and Leaky Bucket Comparisons for the Gini Index of Income Inequality

Transfers, Income Increments and Leaky Bucket Comparisons for the Gini Index of Income Inequality

SIR approach in modeling data packets forwarding at a leaky bucket

When network users are intensively interacting during rush hour, avoiding data loss and latency is a concern in guaranteeing segment reliability. Implementing a leaky bucket could be needed to achieve flows effective monitoring by generating network of queues at given output link. Packets associated with different sessions and originated from different hosts may be mixed up and queuing delay may become longer, depending on network segment state, buffering strategy, users’ behavior among other factors. It is interesting to assimilate these stages of packets traveling through network segment to the concept of epidemic control. This paper proposes a SIR (Susceptible–Infected–Recovered) approach in modeling data packets transmission at a leaky bucket at peak hour. We focused our analysis on packets buffering and recovery strategy impact on segment forwarding performance in heavy load situation. Numerical results suggested adapting buffering strategy and packets recovery to enhance transmission and network overall performance.

Multiple measures of monsoon-controlled water storage in Asia

Temporal water storage is a fundamental component of the terrestrial water cycle. Methods of estimating water storage variations are often limited to specific, well-monitored locations, and/or system scales. Thus, measures of storage from small systems can be difficult to compare to large systems. Here we compare three independent methods of estimating water storage variations for systems spanning over three orders of magnitude in basin area: 1) remote satellite observations (GRACE), 2) hydrograph recession curve analysis, and 3) quantifying precipitation-discharge hysteresis loops. We measured storage using all three methods for 242 watersheds in Asia (103 to 106 km2) and find that GRACE-derived storage correlates well with quantification of hysteresis terms but recession curve derived dynamic storage does not correlate with hysteresis terms or GRACE-derived storage. Thus, we argue that precipitation-discharge hysteresis may be able to be scaled to GRACE-derived storage as an independent estimate of storage for basins as small as 103 km2. Hysteresis-derived storage correlates well with mean monsoon rainfall in the upstream watershed while recession-derived dynamic storage does not. This suggests that hysteresis- and GRACE-derived storage may be input limited. In contrast, recession-derived dynamic storage does not correlate with topographic, climatic, or land cover metrics, suggesting that it may be limited by the rate at which water infiltrates into deep groundwater and then enters the river system. In addition, we find that recession-derived dynamic storage is a factor of seven lower than hysteresis-derived storage. We infer that hysteresis-derived storage includes recession curve-derived storage in addition to other storage units, such as snowpack, lakes, and soil moisture. Recession-derived dynamic storage in turn represents the annual variability in deep groundwater storage, a “leaky bucket” that is recharged from the top and “leaks” into rivers from deeper storage. These data may be able to be used to better quantify storage terms in hydrologic modeling.

“Leaky Bucket” of Kazakhstan’s Power Grid: Losses and Inefficient Distribution of Electric Power

This paper aims to determine and explain the main factors for power losses (the so-called “leaky bucket” effect) in Kazakhstan and the reasons for inefficient energy distribution within the country. Energy efficiency in Kazakhstan is much lower compared to more economically developed countries. The differences between energy efficiency in various regions of Kazakhstan are also significant. This article explores the impact of administrative monopoly tariffs on the regional energy efficiency, based on a national study conducted in Kazakhstan in 2017. The purpose of the study was to identify the administrative barriers and their impact on the sustainability of enterprise development. What hinders the distribution of energy resources among different regions is artificial barriers in the energy market and the administrative tariff monopoly for electric power. This leads to the inefficient distribution of resources throughout the country. In addition, it is difficult to leverage low distribution efficiency in the absence of a market. The authors attempt to prove that the magnitude of administrative barriers directly affects the efficiency and competitiveness of business, as well as the final prices of goods and services for the end consumer.

Facies model on the modern isolated carbonate platform in the Xisha Archipelago, South China Sea

The Xuande Atoll, with a discontinuous reef rim caused by platform drowning, is a typical ellipse isolated platform on the northern slope of the South China Sea. Based on the data of drilling holes, the analysis of surface sediments and high resolution acoustic data, six sedimentary facies are identified in the Xuande Atoll, including reef outer slope, reef front, reef flat, aeolianite sand island, back-reef slope and lagoon. Facies map shows that the elevated reef-rimmed margins with islands are more noticeable on the windward of the platform. With an elevated and discontinuous reef-rimmed margin as well as coarse-grained sediment in the interior platform, Xuande can serve as a case of a leaky bucket atoll which is characterized by initially drowning scenarios. The facies architecture of the Xuande Atoll is evidently influenced by complex and interacting parameters including antecedent topography, sea level, wind-driven currents, water depth and tectonic subsidence. Different controlling factors exist in the drowning of the windward and leeward sides of the platform margin. The study of modern depositional settings in the Xuande Atoll will provide insight on predictions for ancient carbonate provinces.

Analysis of the State-Dependent Queueing Model and Its Application to Battery Swapping and Charging Stations

This study analyzes the performance of a queue length-dependent overload control policy using a leaky bucket (LB) scheme. This queueing model is applied to the operation of a battery swapping and charging station for electric vehicles (EVs). In addition to the LB scheme, we propose two congestion control policies based on EV queue length thresholds. With these policies, the model determines both EV-arrival and battery-supply intervals, and these depend on the number of EVs waiting in the queue. The queue length distributions, including those at arbitrary epochs, are derived using embedded Markov chain and supplementary variable methods. Performance measures such as blocking probability and mean waiting time are investigated using numerical examples. We study the characteristics of the system using numerical examples and use a cost analysis to investigate situations in which the application of each congestion control policy is advantageous.

From Tax Policy to Social Insurance (Presentation Slides)

This presentation was delivered to the Tax Section of the New York State Bar Association in January 2020. It first briefly reviews important current tax policy issues, and shows that the income tax has plenty of headroom to accommodate higher tax revenues: “Personal Income,” the government’s broadest measure of household income, is $6 trillion higher than aggregate Adjusted Gross Incomes. The presentation then pulls back its focus to poverty and middle class life. It argues that education is the engine of economic opportunity, but the United States dishonors the principle of equality of opportunity by its unique reliance on private (family) resources to fund education, particularly among the very young and post-secondary students. Doing more is feasible: the United States is a low-tax country to start, and investment in education yields “inclusive growth.” Efficiency concerns are systematically overstated in many instances, because those analyses do not consider the returns on government investment in education and other programs financed by taxes. Taxes may be carried in leaky buckets, but even a leaky bucket can put out a fire. Finally, the presentation pulls back still further to consider how one might reframe these issues around a unifying theme. It argues that existential bad luck — particularly, bad luck in the wealth of one’s parents — casts a disproportionately long shadow on American lives, and that insurance — understood as both product and metaphor — is the unifying theme that can tie together our responses. In this, the presentation hints at the agenda of my forthcoming book, What’s Luck Got To Do With It?

Fuzzy Leaky Bucket System for Intelligent Management of Consumer Electricity Elastic Load in Smart Grids.

This paper frames itself in an informational rich smart electricity grid where consumers have access to various streams of information and make decisions over their daily consumption pattern. In particular, a new intelligent management system to accommodate possible optimal decisions for elastic load consumption is discussed. The energy management system implements a fuzzy driven leaky bucket that manages the elastic load of a consumer by controlling the token rate buffer via a set of four fuzzy variables (among them the electricity price). The goal of this innovative system is to allow loads that are identified as elastic to be scheduled only when it is potentially beneficial to the consumer. To that end, a fuzzy algorithm comprised of a set of rules is developed to manage the token rate of the leaky bucket and through that the decisions over the fate of elastic loads. The developed system is applied on a set of real-world electricity consumption data taken from a residential consumer, and benchmarked against a full scheduling method, where the elastic load is fully scheduled offline. Results exhibit that the proposed fuzzy logic method outperforms the full scheduling method in the vast majority of the cases, i.e., over 79% of the cases with respect to consumption cost. Furthermore, they validate its ability to conduct real time decision making with no human in the loop.

A Random Compensation Scheme for 5G Slicing Under Statistical Delay-QoS Constraints

For the communication scenarios of heterogeneous arrivals in the fifth generation cellular networks, slicing is believed to be an effective way to provide quality-of-service (QoS) provisioning. However, the reports on an effective segmentation of resources for random and bursty arrival are rare. Relying on the bandwidth estimation and service design, we give a simple but effective scheme for the slicing of bandwidths named two-hole leaky bucket random service mechanism. The service in our scheme comprises two parts, the specific basic service and shared random compensation service. Accordingly, the mechanism of resource allocation is just like leaky bucket with two holes, one of which has a random leak rate. To guarantee the statistical QoS of heterogeneous traffic flows, effective bandwidth/capacity theory is introduced into the slicing scheme. By establishing function equations, we deduce the compensation probability of each slice, which is taken as the slicing adjustment factor. Simulation results prove that the random compensation scheme can satisfy the statistical QoS requirements of heterogeneous traffic flows. Although the scheme is proved to be effective against two slices, the proposed model is applicable to general multiple heterogeneous arrivals.

Sustainability Analysis for Fog Nodes With Renewable Energy Supplies

There is a growing interest in the use of renewable energy sources to power fog networks in order to mitigate the detrimental effects of conventional energy production. However, renewable energy sources, such as solar and wind, are by nature unstable in their availability and capacity. The dynamics of energy supply hence impose new challenges for network planning and resource management. In this paper, the sustainable performance of a fog node powered by renewable energy sources is studied. We develop a generic analytical model to study the energy sustainability of fog nodes powered by renewable energy sources, by generalizing the leaky bucket model to shape and police traffic source for rate-based congestion control in high-speed fog networks. Based on the closed-form solutions of energy buffer analysis, i.e., the energy depletion probability and mean energy length, we study the energy sustainability in two special but real-happening scenarios. The experimental results show that with proper design the leaky bucket model effectively reflects the energy sustainability of data traffic in fog networks. Numerical results also reveal that the model performance is sensitive to certain traffic source characteristics in fog networks.

Critical Tax Thinking

This presentation considers the aims of critical tax studies and offers three suggestions. First, critical tax papers too often fixate on taxes as both the problem and the solution. In many cases, in particular when progressivity is the aim, public spending is the better policy lever. Second, one should not concede that taxation imposes an inexorable tradeoff between efficiency and equity goals. This again understates the importance of the spending side of things. Taxes are a necessary cost of funding spending, and spending in turn, by reaching places where markets are incomplete, can have efficiency payoffs greater than the deadweight loss of taxation. That is, even a leaky bucket can extinguish a fire. To this end, recent research has pointed to the role of well-designed government spending in encouraging an “inclusive economy,” in which growth is both faster and more broadly shared than would otherwise be the case. Finally, the presentation urges that more work be done on the rhetoric of public finance economics. Both the structure and the vocabulary of standard presentations contained unexamined biases that color the outcomes of policy debates.