Using Input-Output Diagram To Determine Spatial and Temporal Extents of a Queue Upstream of a Bottleneck

1997 ◽  
Vol 1572 (1) ◽  
pp. 140-147 ◽  
Author(s):  
Tim W. Lawson ◽  
David J. Lovell ◽  
Carlos F. Daganzo
Keyword(s):  
Simple Approach ◽  
Traffic Signal ◽  
Maximum Length ◽  
Cumulative Number ◽  
Input Output ◽  
Time Space ◽  
The Difference ◽  
Bottleneck Capacity

A simple approach is described for modifying an input-output (or queue-ing) diagram to measure the time and distance spent by vehicles in a queue in a much simpler and self-serving manner than a time-space diagram. The graphic technique requires construction of a curve depicting the cumulative number of vehicles to have reached the back of the queue as a function of time, but, as indicated here, the technique can be easily automated with a spreadsheet. The technique is applied to the simple case of a constant departure rate from a bottleneck and to the slightly more general case of a bottleneck capacity that changes once, which is demonstrated to be applicable to the study of an undersaturated traffic signal. In the course of describing the usefulness of this technique for estimating several measures, including the maximum length of a physical queue and the time when this maximum occurs, the difference between “delay” at a bottleneck and the “time spent in queue,” which appears to have been confused in some of the literature, is clarified.

Simple, Generalized Method for Analysis of Traffic Queue Upstream of a Bottleneck

1998 ◽  
Vol 1646 (1) ◽  
pp. 132-140 ◽  
Author(s):  
Alan L. Erera ◽  
Tim W. Lawson ◽  
Carlos F. Daganzo
Keyword(s):  
Traffic Flow ◽  
Piecewise Linear ◽  
Wave Theory ◽  
Flow Density ◽  
Cumulative Number ◽  
Kinematic Wave ◽  
Input Output ◽  
Original Technique ◽  
Time Space ◽  
Bottleneck Capacity

An approach is generalized for enhancing a standard input-output diagram to represent graphically the time and distance that vehicles spend in a queue upstream of a bottleneck. The approach requires the construction of a curve depicting the cumulative number of vehicles to have reached the back of the queue as a function of time. The original technique, described in a previous paper, is reviewed for bottlenecks with constant capacity and for those where capacity changes once. The approach is then generalized to allow multiple changes in bottleneck capacity, and the original assumption of a triangular flow-density ( q-k) relation is relaxed to one that is piecewise-linear concave. Although it is consistent with the kinematic wave theory of traffic flow, the proposed approach is simpler to apply to complex problems because it avoids the laborious construction of a time-space diagram. It allows the estimation of several measures required in the evaluation of the impacts of bottlenecks, including the (accurate) number of vehicles in queue and the physical extents of queues at any time and the total time spent by vehicles in different traffic states.

scholarly journals Can clearcuts increase bird species richness in managed forests?

2008 ◽  
Vol 54 (No. 4) ◽  
pp. 189-193
Author(s):  
M. Żmihorski
Keyword(s):  
Species Richness ◽  
Bird Species ◽  
Bird Communities ◽  
Cumulative Number ◽  
Managed Forests ◽  
Managed Forest ◽  
Bird Species Richness ◽  
Forest Interior ◽  
Transect Counts ◽  
The Difference

Clearcuts are one of the results of forest management. The aim of this study was to assess the effect of clearcuts on bird communities in a managed forest in Western Poland. I applied the method of point transect counts. 20 points were located near clearcuts (less than 100 m from the nearest clearcut) and 25 points in the forest interior. In total, 36 bird species were recorded. On average, I found 9.20 bird species at points located near clearcuts and 6.72 species at points situated in the forest interior, and the difference was significant. The cumulative number of bird species for a given number of sampling points in the vicinity of clearcuts was higher than in the forest interior. The obtained results indicate that in managed, even-aged forests the generation of clearcuts can lead to an increase in local bird species richness.

scholarly journals Research on the public sports service efficiency and spatial-temporal evolution in China

2021 ◽  
Author(s):  
JIAO LINYAN ◽  
QIAO ZIWEI ◽  
MI SIMENG ◽  
Jung Woo Jin
Keyword(s):  
Spatial Data ◽  
Evaluation Index System ◽  
Spatial Data Analysis ◽  
Eastern Region ◽  
Data Envelopment ◽  
Input Output ◽  
Super Efficiency ◽  
The Public ◽  
Output Efficiency ◽  
The Difference

<p>Taking 31 provinces as the research object, this paper constructed the input-output efficiency evaluation index system of public sports service in China. The paper evaluated the input-output efficiency level and spatial-temporal pattern of public sports services using the methods of data envelopment analysis and exploratory spatial data analysis. The results show that: (1) The average comprehensive super-efficiency value of public sports service in 2016 was higher than that in 2008, and the provinces with the comprehensive super-efficiency value greater than 1 increased, but the difference between provinces in 2016 was more obvious. (2) Compared with 2008, the efficiency distribution of public sports service in 2016 is more balanced among the three regions, the difference between the eastern region and the central region is reduced. (3) The efficiency of public sports service has different spatial correlation in the geographical spatial distribution, and this correlation shows the reverse in the two measurements.</p>

scholarly journals LOGIC OF RELATIVITY

2021 ◽  
pp. 42-52
Author(s):  
Ihor Ohirko ◽  
Zinovii Partyko
Keyword(s):  
Modal Logic ◽  
Symbolic Logic ◽  
Logical Theory ◽  
Relative Truth ◽  
Time Space ◽  
Different Types ◽  
Logical Method ◽  
Standard Values ◽  
The Difference ◽  
Modal Values

The problem of the truth of statements is considered. This study had the goal to develop a logical theory that would allow considering the context (the paradigm) from which would depend on the truth of the statement. For the development of such a theory, called the logic of relativity, the following methods of research are used as abstraction, analysis (traditional), synthesis, deduction, formalisation, axiomatisation, logical method. In order to develop the logic of relativity, it is expedient to use the achievements in the area of situational logic. Under the situation, it is proposed to understand two circumstances (time and space) and a condition that creates a context (paradigm) statement. Specifies the modal values that these three parameters can acquire and examines different types of situations. In order to write statements in the logic of relativity, a form of the statement of statements is proposed in the language of extended symbolic logic. For the theory of the logic of relativity, a set of four axioms is proposed and a series of laws. In particular, it is indicated that the values of the assertions in the logic of relativity are the following five estimates: truth, relative truth, relative is absurd, unclear, uncertain. Some theorems of the logic of relativity are proposed. A number of examples of texts in the natural language are given to interpret the statements of the logic of relativity. It is indicated that the proposed apparatus of the logic of relativity should be regarded as a kind of modal logic. The difference in the logic of relativity from situational logic is that it considers the factor of movement (motion) of statements in time, space and environment conditions, which was not considered by situational logic. The logic of relativity should be used wherever it is necessary to take into account the possibility of moving allegations regarding time, space and environment of conditions. One of the most important conclusions of the study is that in the logic to the standard values of truth (true, probably true, false, uncertain), it is expedient to add another value: relatively true (and accordingly: relatively false).

scholarly journals A simple approach for monitoring vegetation change using time series remote sensing analysis: A case study from the Thathe Vondo Area in Limpopo Province, South Africa

2021 ◽  
Vol 117 (7/8) ◽  
Author(s):  
Nndanduleni Muavhi
Keyword(s):  
Time Series ◽  
Vegetation Cover ◽  
Vegetation Change ◽  
Vegetation Index ◽  
Simple Approach ◽  
Limpopo Province ◽  
Difference Image ◽  
Normalised Difference Vegetation Index ◽  
Gain And Loss ◽  
The Difference

This study presents a simple approach of spatiotemporal change detection of vegetation cover based on analysis of time series remotely sensed images. The study was carried out at Thathe Vondo Area, which is characterised by episodic variation of vegetation gain and loss. This variation is attributable to timber and tea plantations and their production cycles, which periodically result in either vegetation gain or loss. The approach presented here was implemented on two ASTER images acquired in 2007 and 2017. It involved the combined use of band combination, unsupervised image classification and Normalised Difference Vegetation Index (NDVI) techniques. True colour composite (TCC) images for 2007 and 2017 were created from combination of bands 1, 2 and 3 in red, blue and green, respectively. The difference image of the TCC images was then generated to show the inconsistencies of vegetation cover between 2007 and 2017. For analytical simplicity and interpretability, the difference image was subjected to ISODATA unsupervised classification, which clustered pixels in the difference image into eight classes. Two ISODATA derived classes were interpreted as vegetation gain and one as vegetation loss. These classes were confirmed as regions of vegetation gain and loss by NDVI values of 2007 and 2017. In addition, the polygons of vegetation gain and loss regions were created and superimposed over the TCC images to further demonstrate the spatiotemporal vegetation change in the area. The vegetation change statistics show vegetation gain and loss of 10.62% and 2.03%, respectively, implying a vegetation gain of 8.59% over the selected decade.

scholarly journals Power system voltage collapse prediction using a new line stability index (NLSI-1): A case study of the 330-kV nigerian national grid

2019 ◽  
Vol 9 (6) ◽  
pp. 5125
Author(s):  
I. A. Samuel ◽  
J. Katende ◽  
C. O. A. Awosope ◽  
A. A. Awelewa ◽  
A. I. Adekitan ◽  
...  
Keyword(s):  
Power System ◽  
Stability Index ◽  
Base Case ◽  
Voltage Collapse ◽  
Cumulative Number ◽  
The Novel ◽  
A Value ◽  
System Collapse ◽  
The Difference ◽  
Reliability Issue

The cumulative number of historical and recent power system outages substantiates the fact that further studies are necessary for an improved solution to the issue of voltage instability on the grid and the subsequent system collapse. Voltage collapse is a serious reliability issue which inhibits the objective of running a reliable and secure power system network. In this study, a new line stability index (NLSI_1) for predicting voltage collapse is presented.  The new index considers a switching logic which is derived from the difference of voltage angle between the two load buses. The index is deployed for performance analysis using the 28-bus, 330-kV Nigeria National Grid (NNG).  The simulation implemented in MATLAB shows that the index gives the same results as Line stability index (Lmn) and Fast Voltage Stability Index (FVSI) indices. The base case and the contingency scenarios were considered during the simulation. The base case analysis using the NNG values of all the three indices FVSI, Lmn, and NLSI_1 for simulation generates a value less than one for the entire lines which implies that the NNG is stable in this mode. The values of the three indices are almost the same, which confirms the accuracy of the novel index developed. The analysis for the contingency case reveals that the load bus 16 (Gombe) which has the lowest, maximum permissible reactive load of 139.5MVAR is the weakest; also power line 16-19 is identified as the critical line. The result of the simulation confirms that the accuracy was improved by using NLSI_1.

A New Method for Overconstraint Analysis Based on Kinematic Compatibility of Single-Opened-Chains

2000 ◽  
Author(s):  
Qiong Jin ◽  
Lu-Bin Hang ◽  
Ting-Li Yang
Keyword(s):  
New Method ◽  
Input Output ◽  
Compatibility Conditions ◽  
The Difference ◽  
Overconstrained Mechanisms

Abstract A new method for analyzing overconstrained mechanisms is presented in this paper according to the kinematic compatibility criterion of single-opened-chains (SOCs). This criterion states that: if for any value of an active input, two SOCs have die same distances and angles between two ending axes of each SOC, and the difference of axis-lengths corresponding to each hand-side for two SOCs is kept constant, then the two SOCs can be combined together as one closure loop which is an overconstrained mechanism. This method is simple with four clear targets. It is quite different from other methods because the input-output relationships of variables can be obtained during overconstraint analysis. In order to find overconstrained mechanisms, we can begin with parts of compatibility conditions to obtain some kinematic relationships, so that the input-output law and the overconstraint conditions satisfying all compatibility relationships could be given. As examples, the 4R overconstrained mechanisms and a 4R2P overconstrained mechanism are proved using this method.

scholarly journals Convergence in National Alcohol Consumption Patterns: New Global Indicators

2017 ◽  
Vol 12 (2) ◽  
pp. 117-148 ◽  
Author(s):  
Alexander J. Holmes ◽  
Kym Anderson
Keyword(s):  
Alcohol Consumption ◽  
Soft Drink ◽  
Consumption Patterns ◽  
Demand Elasticity ◽  
Beverage Type ◽  
Time Space ◽  
Expenditure Data ◽  
Total Alcohol ◽  
The Difference ◽  
Global Indicators

AbstractWith increasing globalisation and interactions between cultures, countries are converging in many ways, including in their consumption patterns. The extent to which this has been the case in alcohol consumption has been the subject of previous studies, but those studies have been limited in scope to a specific region or group of high-income countries or to just one or two types of alcohol. The present study updates earlier findings, covers all countries of the world since 1961, and introduces two new summary indicators to capture additional dimensions of the extent of convergence in total alcohol consumption and in its mix of beverages. It also distinguishes countries according to whether their alcoholic focus was on wine, beer, or spirits in the early 1960s as well as their geographic regions and their real per-capita incomes. For recent years, we add expenditure data and compare alcohol with soft drink retail expenditure, and we show the difference it makes when unrecorded alcohol volumes are included as part of total alcohol consumption. The final section summarizes our findings and suggests that further research could provide new demand elasticity estimates and use econometrics to explain the varying extents of convergence over time, space, and beverage type. (JEL Classifications: D12, L66, N10)

Research on Regional Differences and Convergence of Energy Efficiency in China

2011 ◽  
Vol 347-353 ◽  
pp. 3952-3955 ◽  
Author(s):  
Jian Sheng Zhang
Keyword(s):  
Energy Efficiency ◽  
Convergence Analysis ◽  
Regional Differences ◽  
Western Region ◽  
Input Output ◽  
The West ◽  
Regional Energy ◽  
The Difference ◽  
Convergence Trend ◽  
Output Indicators

Basing on the input-output indicators, this paper analysed the regional energy efficiency of China by DEA model. The results showed: the energy efficiency in each region of China continues to be improved, but the rising speed was slow; the difference of energy efficiency in each region was great, specifically speaking, the east was the best and the middle was better and the west was the worst; from the convergence analysis on energy efficiency, it indicated that there was a convergence trend on energy efficiency in each region of China, and the eastern and middle regions were convergence, but it was divergent in the western region.

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