scholarly journals Designing Dynamic Delivery Parking Spots in Urban Areas to Reduce Traffic Disruptions

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Mireia Roca-Riu ◽  
Jin Cao ◽  
Igor Dakic ◽  
Monica Menendez
Keyword(s):  
Urban Areas ◽  
Local Level ◽  
Hydrodynamic Theory ◽  
Time Varying ◽  
Traffic Demand ◽  
Road Space ◽  
Delivery Services ◽  
Negative Impacts ◽  
Changes Over Time ◽  
Over Time

Pick-up and delivery services are essential for businesses in urban areas. However, due to the limited space in city centers, it might be unfeasible to provide sufficient loading/unloading spots. As a result, this type of operations often interferes with traffic by occupying road space (e.g., illegal parking). In this study, a potential solution is investigated: Dynamic Delivery Parking Spots (DDPS). With this concept, based on the time-varying traffic demand, the area allowed for delivery parking changes over time in order to maximize delivery opportunities while reducing traffic disruptions. Using the hydrodynamic theory of traffic flow, we analyze the traffic discharging rate on an urban link with DDPS. In comparison to the situation without delivery parking, the results show that although DDPS occupy some space on a driving lane, it is possible to keep the delay at a local level, that is, without spreading to the network. In this paper, we provide a methodology for the DDPS design, so that the delivery requests can be satisfied while their negative impacts on traffic are reduced. A simulation study is used to validate the model and to estimate delay compared to real situations with illegal parking, showing that DDPS can reduce system’s delay.

scholarly journals Viral phylodynamics and the search for an ‘effective number of infections’

2010 ◽  
Vol 365 (1548) ◽  
pp. 1879-1890 ◽  
Author(s):  
Simon D. W. Frost ◽  
Erik M. Volz
Keyword(s):  
Exponential Growth ◽  
Initial Phase ◽  
Epidemiological Data ◽  
Time Varying ◽  
Effective Number ◽  
Epidemiological Models ◽  
Effective Population ◽  
Coalescence Rate ◽  
Changes Over Time ◽  
Over Time

Information on the dynamics of the effective population size over time can be obtained from the analysis of phylogenies, through the application of time-varying coalescent models. This approach has been used to study the dynamics of many different viruses, and has demonstrated a wide variety of patterns, which have been interpreted in the context of changes over time in the ‘effective number of infections’, a quantity proportional to the number of infected individuals. However, for infectious diseases, the rate of coalescence is driven primarily by new transmissions i.e. the incidence, and only indirectly by the number of infected individuals through sampling effects. Using commonly used epidemiological models, we show that the coalescence rate may indeed reflect the number of infected individuals during the initial phase of exponential growth when time is scaled by infectivity, but in general, a single change in time scale cannot be used to estimate the number of infected individuals. This has important implications when integrating phylogenetic data in the context of other epidemiological data.

scholarly journals Inspecting Gradual and Abrupt Changes in Emotion Dynamics With the Time-Varying Change Point Autoregressive Model

2020 ◽  
Vol 36 (3) ◽  
pp. 492-499
Author(s):  
Casper J. Albers ◽  
Laura F. Bringmann
Keyword(s):  
Negative Affect ◽  
Positive Affect ◽  
Change Point ◽  
A Priori ◽  
Ar Model ◽  
Time Varying ◽  
Abrupt Changes ◽  
Emotion Dynamics ◽  
Changes Over Time ◽  
Over Time

Abstract. Recent studies have shown that emotion dynamics such as inertia (i.e., autocorrelation) can change over time. Importantly, current methods can only detect either gradual or abrupt changes in inertia. This means that researchers have to choose a priori whether they expect the change in inertia to be gradual or abrupt. This will leave researchers in the dark regarding when and how the change in inertia occurred. Therefore in this article, we use a new model: the time-varying change point autoregressive (TVCP-AR) model. The TVCP-AR model can detect both gradual and abrupt changes in emotion dynamics. More specifically, we show that the inertia of positive affect and negative affect measured in one individual differs qualitatively in how it changes over time. Whereas the inertia of positive affect increased only gradually over time, negative affect changed both in a gradual and abrupt fashion over time. This illustrates the necessity of being able to model both gradual and abrupt changes in order to detect meaningful quantitative and qualitative differences in temporal emotion dynamics.

scholarly journals Time-varying impact of U.S. financial conditions on China's inflation: a perspective of different types of events

2021 ◽  
Vol 5 (4) ◽  
pp. 604-622
Author(s):  
Yanhong Feng ◽  
◽  
Shuanglian Chen ◽  
Wang Xuan ◽  
Tan Yong ◽  
...  
Keyword(s):  
Financial Market ◽  
Trade Flow ◽  
Time Varying ◽  
Vector Autoregressive ◽  
Financial Conditions ◽  
Time Varying Parameter ◽  
Different Types ◽  
Changes Over Time ◽  
Over Time ◽  
Time Point

<abstract> <p>In recent years, the frequency adjustment of U.S. monetary policy has a dynamic and global impact on other countries' economy. Based on the financial conditions index (FCI), the paper employs the time-varying parameter vector autoregressive model with stochastic volatility (TVP-VAR-SV) and spillover index respectively to investigate the time-varying impact of U.S. financial conditions (UFCI) on China's inflation (CINF) and its impact mechanisms. Some results are achieved as follows: first, the impacts of UFCI on CINF vary greatly over time both in the dimension of action duration and time point. Second, the effects of UFCI on CINF directly relate to different types of major events, and they are heterogeneous in action duration, degree, direction as well as the trend and range of fluctuations. In addition, UFCI can work on CINF through trade flow and China's financial market, and the China's financial market plays a main conductive role, and its conductive effect changes over time.</p> </abstract>

scholarly journals Typifying Guinea Pig (Cavia Porcellus) Farmers in Urban and Peri-Urban Areas in Central and Southern Côte d'lvoire

2011 ◽  
Vol 40 (4) ◽  
pp. 323-328 ◽  
Author(s):  
N'Goran David Vincent Kouakou ◽  
Niko Speybroeck ◽  
Nogbou Emmanuel Assidjo ◽  
Jean-François Grongnet ◽  
Eric Thys
Keyword(s):  
Guinea Pig ◽  
Urban Areas ◽  
Cultural Background ◽  
Cavia Porcellus ◽  
Pig Production ◽  
Socioeconomic Profile ◽  
Preliminary Study ◽  
Changes Over Time ◽  
Future Work ◽  
Over Time

Guinea pig production is practised by all strata of society in Côte d'Ivoire, without regard to gender, age, religion, instruction level or community. It is essentially a source of income, but socioeconomic and cultural background significantly influence the approach to guinea pig production. Adult owners use animals as a source of income. Children eat a significant part of the production themselves. Adolescents progress from consumption to marketing. This preliminary study opens the way for future work that could measure changes over time in the socioeconomic profile of guinea pig farmers and the attitude of the population towards guinea pig breeding.

scholarly journals National trends of childhood vaccination coverage in Bangladesh: Understanding gaps from 2011, 2014 and 2017-18 Demographic and Health Surveys data

2021 ◽  
Author(s):  
Satyajit Kundu ◽  
Subarna Kundu ◽  
Bright Opoku Ahinkorah ◽  
Abdul-Aziz Seidu ◽  
Joshua Okyere ◽  
...  
Keyword(s):  
Vaccination Coverage ◽  
Urban Areas ◽  
Health Surveys ◽  
Maternal Education ◽  
Vaccine Coverage ◽  
Immunization Coverage ◽  
Childhood Vaccination ◽  
Demographic And Health Surveys ◽  
Changes Over Time ◽  
Over Time

Abstract Background Vaccination is a safe and cost-effective strategy for protecting children from life-threatening diseases. This study aimed to investigate the changes over time in proportion of vaccination coverage across demographic subgroups in Bangladesh. Method Vaccination coverage for children 12–59 months of age was obtained from Bangladesh’s 2011, 2014, and 2017-18 Demographic and Health Surveys. Three multivariable binary logistic regression models with complete vaccination status at each survey data were used to generate adjusted odds ratios to uncover immunization variations across socio-demographic categories. Further, to detect potential geographic disparities, changes over time were analyzed at both the country and district levels. Findings Vaccination coverage grew from 88.1% in 2011 to 89.2% in 2017–2018, indicating a gap of more than ten percent for complete immunization coverage among children aged 12–59 months. Children aged 23–35 were more likely to have full vaccination compared to those aged 12–23 in 2011 (AOR = 1.6, 95% CI = 1.3–1.9), 2014 (AOR = 1.6, 95% CI = 1.3-2.0), and 2017-18 (AOR = 1.4, 95% CI = 1.1–1.7). The likelihood of full vaccination of children increased with maternal education with the highest odds among women with higher education in 2011 (AOR = 7.2, 95% CI = 4.0-12.9), 2014 (AOR = 4.0, 95% CI = 2.7–5.9), and 2017-18 (AOR = 5.8, 95% CI = 3.5–9.6) compared to those with no formal education. Children born to mothers who lived in urban areas were more likely to have full vaccination in 2011 (AOR = 1.5, 95% CI = 1.3–1.8), 2014 (AOR = 1.4, 95% CI = 1.2–1.7), and 2017-18 (AOR = 1.4, 95% CI = 1.1–1.7) compared to those who lived in rural areas. Children born to mothers who had at least 4 ANC visits were more likely to have full vaccination compared to those with less than 3 ANC visits in 2011 (AOR = 1.6, 95% CI = 1.2-2.0), 2014 (AOR = 1.5, 95% CI = 1.2-2.0), and 2017-18 (AOR = 1.6, 95% CI = 1.2–2.1 During these three surveys, Rangpur division had the highest vaccine coverage rate, while Sylhet division had the lowest vaccination coverage. Conclusion Although there was an improvement in these nationally representative surveys from 2011 to 2017-18, a portion of children still needs to be vaccinated to ensure full immunization coverage. To achieve 100% immunization coverage for all Bangladeshi children, policymakers must integrate vaccine programs with personalized health messaging and assurances of health safety for impoverished children and low-educated mothers. Increased institutional deliveries and prenatal care visits by mothers could assist increase their children's vaccination coverage.

Changes in the Size Distribution of Settlements in England and Wales, 1801–1968

1978 ◽  
Vol 10 (2) ◽  
pp. 163-171 ◽  
Author(s):  
A D Cliff ◽  
B T Robson
Keyword(s):  
Urban Areas ◽  
Data Sets ◽  
England And Wales ◽  
Data Standard ◽  
Population Concentration ◽  
Standard Normal ◽  
Population Sizes ◽  
Changes Over Time ◽  
The 19Th Century ◽  
Over Time

Changes over time in the distribution of settlement sizes in England and Wales are examined by using two data sets: Town population sizes 1801–1911 and the population size of various local government units in 1968. The Cohen and Whitworth random partitioning models are applied to these data. Standard normal deviates show the increasing population concentration in large urban areas during the 19th century and the reversal of this trend in the 20th century, leading to the suggestion of maximum entropy in 1968. A comparison of the Cohen and the rank–size models suggests the greater utility of the former once the primate city is excluded from consideration. The analysis highlights the timing of critical changes in the evolution of the settlement pattern, particularly the reversal of trend in 1901.

Inequalities in urban areas: innovative approaches to complex issues

2002 ◽  
Vol 30 (59_suppl) ◽  
pp. 34-40 ◽  
Author(s):  
Roderick J. Lawrence
Keyword(s):  
Twentieth Century ◽  
Urban Planning ◽  
Infectious Diseases ◽  
Social Development ◽  
Social Determinants ◽  
Urban Areas ◽  
Local Level ◽  
Environmental Policies ◽  
Human Settlement ◽  
Negative Impacts

Urbanization, a characteristic of the twentieth century, is a profound transformation of human settlement processes and their outcomes, which has not been well understood in terms of both positive and negative impacts. This paper argues that the interrelations between urban planning, health, social, and environmental policies have been poorly articulated until now. Although sectoral approaches have often applied remedial and corrective measures to overcome unsatisfactory conditions in urban areas, today we know that infectious diseases stemming from insanitary conditions are not the leading cause of morbidity and mortality in Europe. Nonetheless diverse forms of ill health remain associated with place of work and residence. Therefore, in order to deal with the complexity and diversity of urban areas there is an urgent need to move from conventional, sectoral approaches based on biomedical models of health to coordinated action stemming from an ecological interpretation of health including its social determinants. This kind of approach is presented in order to promote health and social development at the local level.

scholarly journals Opioid Misuse in Missouri: Analyzing Emergency Department Use in Urban/Rural Areas

2018 ◽  
Vol 10 (1) ◽  
Author(s):  
Evan Mobley ◽  
Andrew Hunter ◽  
Whitney Coffey
Keyword(s):  
Emergency Department ◽  
Rural Areas ◽  
Urban Areas ◽  
The State ◽  
Opioid Overdose ◽  
Metro Area ◽  
Urban Rural ◽  
Ed Visits ◽  
Changes Over Time ◽  
Over Time

ObjectiveCompare rate changes over time for Emergency Department (ED) visits due to opioid overdose in urban versus rural areas of the state of Missouri.IntroductionLike many other states in the U.S., Missouri has experienced large increases in opioid abuse resulting in hundreds dying each year and thousands of ED visits due to overdose. Missouri has two major urban areas, St. Louis and Kansas City and a few smaller cities, while the remainder of the state is more rural in nature. The opioid epidemic has impacted all areas in the state but the magnitude of that impact varies as well as the type of opioid used. Missouri Department of Health and Senior Services (MODHSS) maintains the Patient Abstract System (PAS) which contains data from hospitals and ambulatory surgical centers throughout the state. PAS includes data from ED visits including information on diagnoses, patient demographics, and other information about the visit. MODHSS also participates in the Enhanced State Surveillance of Opioid-involved Morbidity and Mortality project (ESOOS). One major aspect of this surveillance project is the collection of data on non-fatal opioid overdoses from ED visits. Through this collection of data, MODHSS analyzed opioid overdose visits throughout the state, how rates compare across urban and rural areas, and how those rates have changed over time.MethodsThe 115 counties in Missouri were organized into the six-level urban-rural classification scheme developed by the National Center for Health Statistics (NCHS). The attached table shows the breakout of counties into the six different categories. The data years analyzed were 2012 through 2016. ED visits due to opioid overdose were identified using case definitions supplied by ESOOS. Overdoses were analyzed in three different categories—all opioids, heroin, and non-heroin opioids. The all opioid category combines heroin and non-heroin opioids. Non-heroin opioids includes prescription drugs such as oxycodone, hydrocodone, fentanyl, and fentanyl analogues. Annual rates per 10,000 were calculated for each county classification using population estimates. Confidence intervals (at 95%) were then calculated using either inverse gamma when the number of ED visits was under 500, or Poisson when the number was 500 or more. Changes over time were calculated using both a year over year method and a 5 year change method.ResultsOverall opioid rates have increased in all geographic areas during the 5 year period analyzed. Large Central Metro and Large Fringe Metro counties had the highest rates of ED visits due to opioid overdose. These two classifications also saw the largest increases in rates. The Large Central Metro counties collectively increased over 125%, while the Large Fringe Metro area increased 130%. Both areas experienced statistically significant increases year-to-year between 2014 and 2016 in addition to the overall 5 year period of 2012-2016.Analysis was also conducted for heroin and non-heroin subsets of opioid abuse. There were important differences in these two groups. For heroin ED visits, the highest rates were found in the Large Central Metro and Large Fringe Metro regions. However, the largest increase in percentage terms were found in the Medium Metropolitan, Micropolitan and Noncore regions which all saw increases of over 300%. Notably, every region experienced increases of over 150%. The Medium Metro had two consecutive years (2013/2014 and 2014/2015) where the heroin ED rate more than doubled.In contrast, non-heroin ED visits did not experience such a large increase over time. Most areas saw small fluctuations year-to-year with moderate overall increases over the 5-year time period. The exception to this trend is the Large Fringe Metro area, which saw increases every year most notably between 2014 and 2015 and had by far the largest 5 year increase at 82%.ConclusionsThe urban areas in Missouri continue to have the highest rates of opioid overdose, however all areas within the state have experienced very large increases in heroin ED visits within the past five years. The increase in heroin ED visits in the rural areas suggests the abuse of heroin has now spread throughout the state, as rates were much lower in 2012. The steady increase in non-heroin opioids unique to the Large Fringe Metro may be due to the availability of fentanyl in urban areas especially the St. Louis area. This possible finding would correspond with the increased deaths due to fentanyl experienced in and around the St. Louis urban area that has been identified through analysis of death certificate data. 

scholarly journals Time-varying properties of asymmetric volatility and multifractality in Bitcoin

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246209
Author(s):  
Tetsuya Takaishi
Keyword(s):  
Hurst Exponent ◽  
Serial Correlation ◽  
Time Varying ◽  
Asymmetric Volatility ◽  
Window Method ◽  
Asymmetric Pattern ◽  
Rolling Window ◽  
Volatility Asymmetry ◽  
Changes Over Time ◽  
Over Time

This study investigates the volatility of daily Bitcoin returns and multifractal properties of the Bitcoin market by employing the rolling window method and examines relationships between the volatility asymmetry and market efficiency. Whilst we find an inverted asymmetry in the volatility of Bitcoin, its magnitude changes over time, and recently, it has become small. This asymmetric pattern of volatility also exists in higher frequency returns. Other measurements, such as kurtosis, skewness, average, serial correlation, and multifractal degree, also change over time. Thus, we argue that properties of the Bitcoin market are mostly time dependent. We examine efficiency-related measures: the Hurst exponent, multifractal degree, and kurtosis. We find that when these measures represent that the market is more efficient, the volatility asymmetry weakens. For the recent Bitcoin market, both efficiency-related measures and the volatility asymmetry prove that the market becomes more efficient.

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