Business Resilience During Power Shortages: A Power Saving Rate Measured by Power Consumption Time Series in Industrial Sector Before and After the Great East Japan Earthquake in 2011

2016 ◽  
pp. 239-257 ◽  
Author(s):  
Yoshio Kajitani
Keyword(s):  
Time Series ◽  
Power Consumption ◽  
Power Saving ◽  
Industrial Sector ◽  
Great East Japan Earthquake ◽  
Saving Rate ◽  
Before And After ◽  
Business Resilience ◽  
Power Shortages

scholarly journals Complexity traits and synchrony of cryptocurrencies price dynamics

2021 ◽  
Author(s):  
Davide Provenzano ◽  
Rodolfo Baggio
Keyword(s):  
Time Series ◽  
Complex Network ◽  
Complex Structures ◽  
Slope Parameter ◽  
Exponential Distributions ◽  
Horizontal Visibility ◽  
Time Period ◽  
Before And After ◽  
Visibility Algorithm ◽  
Similar Complex

AbstractIn this study, we characterized the dynamics and analyzed the degree of synchronization of the time series of daily closing prices and volumes in US$ of three cryptocurrencies, Bitcoin, Ethereum, and Litecoin, over the period September 1,2015–March 31, 2020. Time series were first mapped into a complex network by the horizontal visibility algorithm in order to revel the structure of their temporal characters and dynamics. Then, the synchrony of the time series was investigated to determine the possibility that the cryptocurrencies under study co-bubble simultaneously. Findings reveal similar complex structures for the three virtual currencies in terms of number and internal composition of communities. To the aim of our analysis, such result proves that price and volume dynamics of the cryptocurrencies were characterized by cyclical patterns of similar wavelength and amplitude over the time period considered. Yet, the value of the slope parameter associated with the exponential distributions fitted to the data suggests a higher stability and predictability for Bitcoin and Litecoin than for Ethereum. The study of synchrony between the time series investigated displayed a different degree of synchronization between the three cryptocurrencies before and after a collapse event. These results could be of interest for investors who might prefer to switch from one cryptocurrency to another to exploit the potential opportunities of profit generated by the dynamics of price and volumes in the market of virtual currencies.

scholarly journals Changes in the Use of Broad-Spectrum Antibiotics after Cefepime Shortage: a Time Series Analysis

2011 ◽  
Vol 56 (2) ◽  
pp. 989-994 ◽  
Author(s):  
C. Plüss-Suard ◽  
A. Pannatier ◽  
C. Ruffieux ◽  
A. Kronenberg ◽  
K. Mühlemann ◽  
...  
Keyword(s):  
Time Series ◽  
Pseudomonas Aeruginosa ◽  
Broad Spectrum ◽  
Interrupted Time Series ◽  
Antibiotic Policy ◽  
Content Type ◽  
Broad Spectrum Antibiotics ◽  
Before And After ◽  
Alternative Antibiotic ◽  
The Impact

ABSTRACTThe original cefepime product was withdrawn from the Swiss market in January 2007 and replaced by a generic 10 months later. The goals of the study were to assess the impact of this cefepime shortage on the use and costs of alternative broad-spectrum antibiotics, on antibiotic policy, and on resistance ofPseudomonas aeruginosatoward carbapenems, ceftazidime, and piperacillin-tazobactam. A generalized regression-based interrupted time series model assessed how much the shortage changed the monthly use and costs of cefepime and of selected alternative broad-spectrum antibiotics (ceftazidime, imipenem-cilastatin, meropenem, piperacillin-tazobactam) in 15 Swiss acute care hospitals from January 2005 to December 2008. Resistance ofP. aeruginosawas compared before and after the cefepime shortage. There was a statistically significant increase in the consumption of piperacillin-tazobactam in hospitals with definitive interruption of cefepime supply and of meropenem in hospitals with transient interruption of cefepime supply. Consumption of each alternative antibiotic tended to increase during the cefepime shortage and to decrease when the cefepime generic was released. These shifts were associated with significantly higher overall costs. There was no significant change in hospitals with uninterrupted cefepime supply. The alternative antibiotics for which an increase in consumption showed the strongest association with a progression of resistance were the carbapenems. The use of alternative antibiotics after cefepime withdrawal was associated with a significant increase in piperacillin-tazobactam and meropenem use and in overall costs and with a decrease in susceptibility ofP. aeruginosain hospitals. This warrants caution with regard to shortages and withdrawals of antibiotics.

A comparison of global suicide terrorism by region before and after 9/11 terrorist attacks

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Ahmet Guler ◽  
Mustafa Demir
Keyword(s):  
Time Series ◽  
Interrupted Time Series ◽  
Sub Saharan Africa ◽  
Terrorist Attacks ◽  
Suicide Terrorism ◽  
Content Type ◽  
The World ◽  
Before And After ◽  
Sub Saharan ◽  
Global Terrorism Database

Purpose This study aims to examine the effect of the 9/11 terrorist attacks on suicide terrorism in different regions of the world and changes in the trends in suicide terrorism according to regions before and after 9/11. Design/methodology/approach Using the data obtained from the Global Terrorism Database from 1981 to 2019, the descriptive statistics were computed first and then, independent samples t-tests were run to compare the monthly mean percentage of suicide-terrorism incidents that occurred in each region between the pre-9/11 and the post-9/11 periods. Finally, to statistically assess the effect of the 9/11 attacks and changes in the trends for the dependent variables over time, monthly interrupted time-series analyzes were conducted. Findings The results of monthly interrupted time series analyzes showed that after the 9/11 attacks, the trends for suicide-terrorism rates decreased significantly in three regions including South Asia, the Middle East and North Africa and Europe, while the trend for suicide-terrorism rates increased significantly in Sub-Saharan Africa. However, no statistically significant changes in the trends in suicide-terrorism rates occurred in three regions including North America, East Asia and Central Asia and Southeast Asia before 9/11, during November 2001 or after 9/11. Originality/value This study indicates the critical importance of the 9/11 terrorist attacks in suicide terrorism and its impact on these events in different regions of the world. The research also provides some recommendations concerning the effectiveness of defensive and offensive counterterrorism policies against suicide terrorism.

scholarly journals Toward Green Sensor Field by Optimizing Power Efficiency Using D-Policy M/G/1 Queuing Systems

2013 ◽  
Vol 9 (3) ◽  
pp. 241-260 ◽  
Author(s):  
Fuu-Cheng Jiang ◽  
Hsiang-Wei Wu ◽  
Fang-Yi Leu ◽  
Chao-Tung Yang
Keyword(s):  
Sensor Networks ◽  
Power Consumption ◽  
Power Efficiency ◽  
Ieee 802.15.4 ◽  
Power Saving ◽  
Rechargeable Batteries ◽  
Sensor Nodes ◽  
Traffic Load ◽  
Mathematical Framework ◽  
Sensor Field

Power efficiency is a crucially important issue in the IEEE 802.15.4/ZigBee sensor networks (ZSNs) for majority of sensor nodes equipped with non-rechargeable batteries. To increase the lifetime of sensor networks, each node must optimize power consumption as possible. Among open literatures, much research works have focused on how to optimally increase the probability of sleeping states using multifarious wake-up strategies. Making things different, in this article, we propose a novel optimization framework for alleviating power consumption of sensor node with the D-policy M/G/1 queuing approach. Toward green sensor field, the proposed power-saving technique can be applied to prolong the lifetime of ZSN economically and effectively. For the proposed data aggregation model, mathematical framework on performance measures has been formulated. Data simulation using MATLAB tool has been conducted for exploring the feasibility of the proposed approach. And also we analyze the average traffic load per node for tree-based ZSN. Focusing on ZigBee routers deployed at the innermost shell of ZSN, network simulation results validate that the proposed approach indeed provides a feasibly cost-effective approach for prolonging lifetime of ZSNs.

scholarly journals Changes of China’s agri-food exports to Germany caused by its accession to WTO and the 2008 financial crisis

2015 ◽  
Vol 7 (2) ◽  
pp. 262-279 ◽  
Author(s):  
Zhichao Guo ◽  
Yuanhua Feng ◽  
Thomas Gries
Keyword(s):  
Time Series ◽  
Financial Crisis ◽  
Regression Models ◽  
Structural Breaks ◽  
Global Financial Crisis ◽  
Middle Part ◽  
Change Points ◽  
Content Type ◽  
The World ◽  
Before And After

Purpose – The purpose of this paper is to investigate changes of China’s agri-food exports to Germany caused by China’s accession to WTO and the global financial crisis in a quantitative way. The paper aims to detect structural breaks and compare differences before and after the change points. Design/methodology/approach – The structural breaks detection procedures in this paper can be applied to find out two different types of change points, i.e. in the middle and at the end of one time series. Then time series and regression models are used to compare differences of trade relationship before and after the detected change points. The methods can be employed in any economic series and work well in practice. Findings – The results indicate that structural breaks in 2002 and 2009 are caused by China’s accession to WTO and the financial crisis. Time series and regression models show that the development of China’s exports to Germany in agri-food products has different features in different sub-periods. Before 1999, there is no significant relationship between China’s exports to Germany and Germany’s imports from the world. Between 2002 and 2008 the former depends on the latter very strongly, and China’s exports to Germany developed quickly and stably. It decreased, however suddenly in 2009, caused by the great reduction of Germany’s imports from the world in that year. But China’s market share in Germany still had a small gain. Analysis of two categories in agri-food trade also leads to similar conclusions. Comparing the two events we see rather different patterns even if they both indicate structural breaks in the development of China’s agri-food exports to Germany. Originality/value – This paper partly originally proposes two statistical algorithms for detecting different kinds of structural breaks in the middle part and at the end of a short-time series, respectively.

scholarly journals Microteaching Guided by an Expert Secondary English Teacher: The Effect on Pre-Service English Teachers’ Pedagogical Content Knowledge

Pedagogika ◽  
2020 ◽  
Vol 139 (3) ◽  
pp. 111-135
Author(s):  
Siti Aimah ◽  
Dwi Rukmini ◽  
Mursid Saleh ◽  
Dwi Anggani Linggar Bharati
Keyword(s):  
Time Series ◽  
Content Knowledge ◽  
English Teachers ◽  
English Teacher ◽  
Single Group ◽  
Secondary English ◽  
Pedagogical Content ◽  
Series Design ◽  
Equivalent Time ◽  
Before And After

This study aims to determine the effect of microteaching guided by an expert secondary English teacher on pre-service English teachers PCK, focusing on the changes before and after expert-guided microteaching. The equivalent time-series design involves a single-group, repeatedly assessed, with the treatment introduced between the measurements. Expert-guided microteaching significantly affects pre-service English teachers’ PCK and triggers them to know what to teach and how to teach for students.

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