scholarly journals Mathematical models of short-range dispersal in defoliating lepidopterans

2021 ◽  
Author(s):  
Eli Bussel
Keyword(s):  
Gypsy Moth ◽  
Short Range ◽  
Spatial Dynamics ◽  
Field Research ◽  
Dispersal Kernel ◽  
Dispersal Patterns ◽  
Theoretical Understanding ◽  
Future Studies ◽  
Seed Dispersal Kernel ◽  
Random Diffusion

The gypsy moth (Lymantria dispar) is among the most destructive invasive species in North America, responsible for defoliating millions of hectares of oak forest. The spatial dynamics of defoliating lepidopteran populations, such as those of the gypsy moth, are thus of great interest to forestry and conservation efforts. Despite numerous studies on the long-range dispersal patterns of defoliators, there is comparatively little theoretical understanding or field research concerning short-range dispersal via ballooning. Previous studies of ballooning have assumed random diffusion, but these models cannot account for non-random biases, such as the effect of wind on the angle of dispersal.Here, I develop models of short-range dispersal in larvae via ballooning, informed by methods from the seed dispersal kernel literature. I then fit models to field data of gypsy moth larvae dispersal using MCMC to perform Bayesian inference, and PSIS-LOO to perform model selection. I found that dispersal kernel models are able to reliably detect biases in angle of dispersal due to wind direction, and allow for testing of correlations between experimental variables and measures of dispersal. These modeling methods can help inform future studies into short-range larval dispersal and provide a novel framework with which to analyze dispersal data.

scholarly journals Dispersal Kernel Determines Symmetry of Spread and Geographical Range for an Insect

2009 ◽  
Vol 2009 ◽  
pp. 1-4 ◽  
Author(s):  
Jeffrey D. Holland
Keyword(s):  
Sugar Maple ◽  
Spatial Dynamics ◽  
Geographic Range ◽  
Dispersal Distance ◽  
Dispersal Kernel ◽  
Geographical Range ◽  
Spatial Distributions ◽  
Longhorned Beetle ◽  
Ecological Patterns ◽  
Dispersal Distances

The distance from a source patch that dispersing insects reach depends on the number of dispersers, or random draws from a probability density function called a dispersal kernel, and the shape of that kernel. This can cause asymmetrical dispersal between habitat patches that produce different numbers of dispersers. Spatial distributions based on these dynamics can explain several ecological patterns including megapopulations and geographic range boundaries. I hypothesized that a locally extirpated longhorned beetle, the sugar maple borer, has a new geographical range shaped primarily by probabilistic dispersal distances. I used data on occurrence from Ontario, Canada to construct a model of geographical range in Indiana, USA based on maximum dispersal distance scaled by habitat area. This model predicted the new range boundary within 500 m very accurately. This beetle may be an ideal organism for exploring spatial dynamics driven by dispersal.

Forecasting the spatial dynamics of gypsy moth outbreaks using cellular transition models

1995 ◽  
Vol 10 (3) ◽  
pp. 177-189 ◽  
Author(s):  
Guofa Zhou ◽  
Andrew M. Liebhold
Keyword(s):  
Gypsy Moth ◽  
Spatial Dynamics ◽  
Transition Models

scholarly journals Penerapan Akad Ijarah Pada Produk Pembiayaan Pengurusan Porsi Haji Di KSPPS Kopena Pekalongan Ditinjau Dari Fatwa DSN-MUI

2019 ◽  
Vol 1 (2) ◽  
pp. 45-54
Author(s):  
Danis Amwalul Fikki
Keyword(s):  
Data Collection ◽  
Supervisory Board ◽  
Field Research ◽  
Secondary Data ◽  
Qualitative Approach ◽  
Primary Data ◽  
Future Studies ◽  
Strict Control

Purpose- This study discusses the application of the Ijarah Agreement on Financing Products for the Management of Hajj Portions at KSPPS Kopena Pekalongan Judging from the DSN-MUI Fatwa. Methods- This research is a type of field research with a type of qualitative approach. The data used in this study are primary data obtained from interviews and secondary data obtained from research at KSPPS Kopena Pekalongan. Data were analyzed descriptively, namely data collected in the form of words, images and not numbers. The method of data collection by interviews, documents, and observations. Findings- The results of the study show that financing using the ijarah contract has followed the rules of the MUI DSN Fatwa. It can be stated that KSPPS Kopena Pekalongan has implemented the DSN-MUI Fatwa in each of its products and the Sharia Supervisory Board has always exercised strict control over the application of fatwas at the KSPPS Kopena Pekalongan Implications/limitations - This study is a case study and is only carried out in one agency so that future studies can expand the study area to increase generalization. Adapun hasil penelitian ini, bahwa pembiayaan ini menggunakan akad ijarah sesuai dengan yang diperintahkan dalam Fatwa DSN MUI. Hal ini sesuai dengan yang disampaikan oleh Dewan Pengawas Syariah KSPPS Kopena Pekalongan. Dari uraian di atas dapat disimpulkan bahwa KSPPS Kopena Pekalongan melaksanakan Fatwa DSN-MUI dalam setiap produknya dan Dewan Pengawas Syariah selalu melakukan kontrol yang ketat terhadap penerapan fatwa di KSPPS Kopena Pekalongan.

scholarly journals A NEW PHENOMENOLOGY FOR THE DISORDERED MIXED PHASE

2001 ◽  
Vol 15 (23) ◽  
pp. 1023-1030 ◽  
Author(s):  
GAUTAM I. MENON
Keyword(s):  
Phase Diagram ◽  
Short Range ◽  
Glass Phase ◽  
Significant Degree ◽  
Type Ii ◽  
Weak Point ◽  
Theoretical Understanding ◽  
Type Ii Superconductors ◽  
Bragg Glass ◽  
Thermodynamic Phase

A universal phase diagram for type-II superconductors with weak point pinning disorder is proposed. In this phase diagram, two thermodynamic phase transitions generically separate a "Bragg glass" from the disordered liquid. Translational correlations in the intervening "multi-domain glass" phase are argued to exhibit a significant degree of short-range order. This phase diagram differs significantly from the currently accepted one, but provides a more accurate description of experimental data on high and low-T c materials, simulations and current theoretical understanding.

The analysis of the effect of Islamic financing and labor relationship development toward nonperforming financing in Islamic banks

2018 ◽  
Vol 9 (4) ◽  
pp. 648-660
Author(s):  
Muhammad Bahrul Ilmi
Keyword(s):  
Field Research ◽  
Numerical Data ◽  
Relationship Development ◽  
Annual Reports ◽  
Primary Data ◽  
Future Research ◽  
Islamic Banks ◽  
Content Type ◽  
Future Studies ◽  
Labor Relationship

Purpose The purpose of this study is to examine the effect of Islamic financing (IF) and labor relationship development (LRD) toward nonperforming financing (NPF) in Islamic banks. This research aims to identify the connection between IF products and the practice of loan officers building a relationship with loan customers (also known as LRD) and its influence on NPF. Design/methodology/approach This study uses a quantitative field research that emphasizes upon analysis of numerical data which are processed with statistical methods. Furthermore, the source is secondary data from financial statements of Islamic banks such as annual reports or financial disclosures. These sources of data are used to examine NPF facilities from 2008 to 2012. Moreover, primary data collected via questionnaire are used to investigate IF and LRD. The banks where the study was conducted are: Bank Muamalat Indonesia and Bank Danamon Shari’ah in Surakarta, Indonesia. The population in this study is 15 employees who work as account officers in Bank Muamalat Indonesia and Bank Danamon Shari’ah. The techniques of data collection in this study are documentation, questionnaires and literary study. In this study, the data analysis technique was multiple regression analysis and examination using SPSS version 21. These methods were used for analyzing the effect of IF and LRD toward NPF. Findings IF has a significant effect on NPF. In contrast, the LRD has no effect on NPF in Islamic banks. In addition, both IF and LRD simultaneously had an effect on NPF in Islamic banks. Research limitations/implications This study does not cover all Islamic banks in Surakarta because of limited data; thus, in future research, the sample size could be increased by including all Islamic banks in Surakarta, Indonesia. Furthermore, this study does not take into consideration the fact that IF includes product financing. For future studies, the population and samples should be improved and take into consideration that product financing does exist in Islamic banks; moreover, future studies could provide other variables which are appropriate for current studies. Originality/value The results support the recommendation for Islamic banks in Surakarta to enhance the capability of employees to develop their knowledge in IF. Because the performance of a bank does not only depict financial performance but also nonfinancial performance such as services, knowledge and employees’ performance.

An integrated perspective of value creation and capture: a systematic literature review

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Claudio Minerbo ◽  
Luiz Artur Ledur Brito
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Value Creation ◽  
Operations Management ◽  
Theoretical Understanding ◽  
Value Capture ◽  
Content Type ◽  
Future Studies ◽  
Practical Guidelines ◽  
Value Creation And Capture

Purpose The existing literature is fragmented across disciplines and does not provide a holistic, comprehensive view on how value is created, deployed and captured. This paper aims to provide a structured view of the current literature and facilitates a theoretical understanding of value creation and capture in buyer–supplier relationships. Design/methodology/approach A systematic literature review was conducted on 195 articles published in 21 leading journals in marketing, operations management and strategy disciplines. Findings An integrated, generalizable and expandable framework is proposed based on the causal or interactive relationship among four components, namely, dimensions of value creation; processes and interactions by which buyers and suppliers enable value creation; relationship characteristics that affect these components; and value capture. Two new areas for future studies are also suggested. Research limitations/implications The findings are based on papers published in peer-reviewed academic literature. Future studies could include more heterogeneous publications in languages other than English and/or professional journals to compare scholars' and managers' perspectives. Practical implications This study offers simple, practical guidelines that managers can apply in their real-world situations to increase the value they gain from their relationships. Originality/value The framework does not pretend to be exhaustive because such an attempt would be impractical. Rather, this study provides practical examples for each component, and shows how additional concepts and constructs can be incorporated to make it inclusive and generalizable. Two new manners of value capture other than price negotiations are presented (volume and collaborative benefits).

Seed dispersal kernel of the largest surviving megaherbivore-the African savanna elephant

Biotropica ◽  
2017 ◽  
Vol 49 (3) ◽  
pp. 395-401 ◽  
Author(s):  
Katherine Bunney ◽  
William J. Bond ◽  
Michelle Henley
Keyword(s):  
Seed Dispersal ◽  
Dispersal Kernel ◽  
African Savanna ◽  
Savanna Elephant ◽  
Seed Dispersal Kernel

Geostatistical Model for Forecasting Spatial Dynamics of Defoliation Caused by the Gypsy Moth (Lepidoptera: Lymantriidae)

1993 ◽  
Vol 22 (5) ◽  
pp. 1066-1075 ◽  
Author(s):  
Michael E. Hohn ◽  
Andrew M. Liebhold ◽  
Linda S. Gribko
Keyword(s):  
Gypsy Moth ◽  
Spatial Dynamics ◽  
Geostatistical Model

scholarly journals Application of Short-Range LIDAR in Early Alerting for Low-Level Windshear and Turbulence at Hong Kong International Airport

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
K. K. Hon ◽  
P. W. Chan ◽  
Y. Y. Chiu ◽  
Wenbo Tang
Keyword(s):  
Hong Kong ◽  
Short Range ◽  
Field Research ◽  
Relative Operating Characteristic ◽  
Low Level ◽  
International Airport ◽  
The North ◽  
Set Up ◽  
Hong Kong International Airport ◽  
Meteorological Instruments

Hong Kong Observatory currently uses a series of meteorological instruments, including long-range LIDAR (light detection and ranging) systems, to provide alerting services of low-level windshear and turbulence for Hong Kong International Airport. For some events that are smaller in spatial dimensions and are rapidly changing, such as low altitude windshear and turbulence associated with buildings or man-made structures, it would be necessary to involve meteorological instruments that offer greater spatial resolution. Therefore, the Observatory has set up a short-range LIDAR on the roof of the AsiaWorld-Expo during the summers over the past several years, conducting field research on the feasibility of strengthening early alerting for windshear and turbulence over the north runway’s eastern arrival runway (Runway 25RA) and developing an automated early alerting algorithm. This paper takes the pilot reports for Runway 25RA during the 2013 field research as verification samples, using different thresholds for radial wind velocity spatial and temporal changes detected by the short-range LIDAR to calculate the relative operating characteristic (ROC) curve, and analyzes its early alerting performance.

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