scholarly journals Decomposition of Repulsive Clusters in Complex Point Processes with Heterogeneous Components

2019 ◽  
Vol 8 (8) ◽  
pp. 326
Author(s):  
Ci Song ◽  
Tao Pei

The decomposition of a point process is useful for the analysis of spatial patterns and in the discovery of potential mechanisms of geographic phenomena. However, when a local repulsive cluster is present in a complex heterogeneous point process, the traditional solution, which is based on clustering, may be invalid for decomposition because a repulsive pattern is not subject to a specific probability distribution function and the effects of aggregative and repulsive components may be counterbalanced. To solve this problem, this paper proposes a method of decomposing repulsive clusters in complex point processes with multiple heterogeneous components. A repulsive cluster is defined as a set of repulsive density-connected points that are separated by a certain distance at a small scale and aggregated at a large scale simultaneously. The H-function is used to identify repulsive clusters by determining the repulsive distance and extracting repulsive points for further clustering. Through simulation experiments based on three datasets, the proposed method has been shown to effectively perform repulsive cluster decomposition in heterogeneous point processes. A case study of the point of interest (POI) dataset in Beijing also indicates that the method can identify meaningful repulsive clusters from types of POIs that represent different service characteristics of shops in different local regions.

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1049
Author(s):  
Zhang Deng ◽  
Yixing Chen ◽  
Xiao Pan ◽  
Zhiwen Peng ◽  
Jingjing Yang

Urban building energy modeling (UBEM) is arousing interest in building energy modeling, which requires a large building dataset as an input. Building use is a critical parameter to infer archetype buildings for UBEM. This paper presented a case study to determine building use for city-scale buildings by integrating the Geographic Information System (GIS) based point-of-interest (POI) and community boundary datasets. A total of 68,966 building footprints, 281,767 POI data, and 3367 community boundaries were collected for Changsha, China. The primary building use was determined when a building was inside a community boundary (i.e., hospital or residential boundary) or the building contained POI data with main attributes (i.e., hotel or office building). Clustering analysis was used to divide buildings into sub-types for better energy performance evaluation. The method successfully identified building uses for 47,428 buildings among 68,966 building footprints, including 34,401 residential buildings, 1039 office buildings, 141 shopping malls, and 932 hotels. A validation process was carried out for 7895 buildings in the downtown area, which showed an overall accuracy rate of 86%. A UBEM case study for 243 office buildings in the downtown area was developed with the information identified from the POI and community boundary datasets. The proposed building use determination method can be easily applied to other cities. We will integrate the historical aerial imagery to determine the year of construction for a large scale of buildings in the future.


2017 ◽  
Vol 22 (6) ◽  
pp. 486-505 ◽  
Author(s):  
Benjamin Tukamuhabwa ◽  
Mark Stevenson ◽  
Jerry Busby

Purpose In few prior empirical studies on supply chain resilience (SCRES), the focus has been on the developed world. Yet, organisations in developing countries constitute a significant part of global supply chains and have also experienced the disastrous effects of supply chain failures. The purpose of this paper is therefore to empirically investigate SCRES in a developing country context and to show that this also provides theoretical insights into the nature of what is meant by resilience. Design/methodology/approach Using a case study approach, a supply network of 20 manufacturing firms in Uganda is analysed based on a total of 45 interviews. Findings The perceived threats to SCRES in this context are mainly small-scale, chronic disruptive events rather than discrete, large-scale catastrophic events typically emphasised in the literature. The data reveal how threats of disruption, resilience strategies and outcomes are inter-related in complex, coupled and non-linear ways. These interrelationships are explained by the political, cultural and territorial embeddedness of the supply network in a developing country. Further, this embeddedness contributes to the phenomenon of supply chain risk migration, whereby an attempt to mitigate one threat produces another threat and/or shifts the threat to another point in the supply network. Practical implications Managers should be aware, for example, of potential risk migration from one threat to another when crafting strategies to build SCRES. Equally, the potential for risk migration across the supply network means managers should look at the supply chain holistically because actors along the chain are so interconnected. Originality/value The paper goes beyond the extant literature by highlighting how SCRES is not only about responding to specific, isolated threats but about the continuous management of risk migration. It demonstrates that resilience requires both an understanding of the interconnectedness of threats, strategies and outcomes and an understanding of the embeddedness of the supply network. Finally, this study’s focus on the context of a developing country reveals that resilience should be equally concerned both with smaller in scale, chronic disruptions and with occasional, large-scale catastrophic events.


Author(s):  
Ilda Vagge ◽  
◽  
Gioia Maddalena Gibelli ◽  
Alessio Gosetti Poli ◽  
◽  
...  

The authors, with the awareness that climate change affects and changes the landscape, wanted to investigate how these changes are occurring within the metropolitan area of Tehran. Trying to keep a holistic method that embraces different disciplines, reasoning from large scale to small scale, the authors tried to study the main problems related to water scarcity and loss of green spaces. Subsequently they dedicated themselves to the identification of the present and missing ecosystem services, so that they could be used in the best possible way as tools for subsequent design choices. From the analysis obtained, the authors have created a masterplan with the desire to ensure a specific natural capital, the welfare of ecosystem services, and at the same time suggest good water management practices. It becomes essential to add an ecological accounting to the economic accounting, giving dignity to the natural system and the ecosystem services that derive from it.


Author(s):  
Anjan Pakhira ◽  
Peter Andras

Testing is a critical phase in the software life-cycle. While small-scale component-wise testing is done routinely as part of development and maintenance of large-scale software, the system level testing of the whole software is much more problematic due to low level of coverage of potential usage scenarios by test cases and high costs associated with wide-scale testing of large software. Here, the authors investigate the use of cloud computing to facilitate the testing of large-scale software. They discuss the aspects of cloud-based testing and provide an example application of this. They describe the testing of the functional importance of methods of classes in the Google Chrome software. The methods that we test are predicted to be functionally important with respect to a functionality of the software. The authors use network analysis applied to dynamic analysis data generated by the software to make these predictions. They check the validity of these predictions by mutation testing of a large number of mutated variants of the Google Chrome. The chapter provides details of how to set up the testing process on the cloud and discusses relevant technical issues.


Author(s):  
Hans-Jörg Schmid

This chapter discusses how the Entrenchment-and-Conventionalization Model explains language change. First, it is emphasized that not only innovation and variation, but also the frequency of repetition can serve as important triggers of change. Conventionalization and entrenchment processes can interact and be influenced by numerous forces in many ways, resulting in various small-scale processes of language change, which can stop, change direction, or even become reversed. This insight serves as a basis for the systematic description of nine basic modules of change which differ in the ways in which they are triggered and controlled by processes and forces. Large-scale pathways of change such as grammaticalization, lexicalization, pragmaticalization, context-induced change, or colloquialization and standardization are all explained by reference to these modules. The system is applied in a case study on the history of do-periphrasis.


2019 ◽  
Vol 112 ◽  
pp. 02011
Author(s):  
Cristian-Gabriel Alionte ◽  
Daniel-Constantin Comeaga

The importance of renewable energy and especially of eolian systems is growing. For this reason, we propose the investigation of an important pollutant - the noise, which has become so important that European Commission and European Parliament introduced Directive 2002/49/CE relating to the assessment and management of environmental noise. So far, priority has been given to very large-scale systems connected to national energy systems, wind farms whose highly variable output power could be regulated by large power systems. Nowadays, with the development of small storage capacities, it is feasible to install small power wind turbines in cities of up to 10,000 inhabitants too. As a case study, we propose a simulation for a rural locality where individual wind units could be used. This specific case study is interesting because it provides a new perspective of the impact of noise on the quality of life when the use of this type of system is implemented on a large scale. This option, of distributed and small power wind turbine, can be implemented in the future as an alternative or an adding to the common systems.


2008 ◽  
Vol 2008 (1) ◽  
pp. 1163-1169
Author(s):  
Leslie J. Craig ◽  
Tom Pride

ABSTRACT The use of pilot studies can be a useful tool in determining the most appropriate location, method and design for a large scale restoration project. This paper provides a case study where Trustees implemented a small pilot project and feasibility study to determine the best approach for a large scale oyster reef creation project. While the specific case study is the result of a CERCLA settlement (Alafia River Acid Spill of 1997), this model is transferable to other instances where Trustees are scoping for the most appropriate sites and methods to conduct settlement funded restoration. The Restoration Plan and Environmental Assessment on which the case settlement was based called for creation of approximately 4 acres of oyster reef in addition to 4 acres of estuarine marsh restoration. Through an initial scoping process, the Trustees determined that more information was needed to select the most appropriate locations and techniques to implement the large scale oyster restoration project. The Trustees identified 3 general locations with potential for larger scale oyster reef creation. A portion of settlement funding was used to contract for construction and monitoring of an oyster reef pilot project to examine the efficacy of oyster reef construction at the three locations using 4 different cultch materials. At each of the locations, 4 small reefs (approximately 75’ × 20’) were constructed and monitored for spat set, oyster survival and growth as well as subsidence. A baseline construction report and final monitoring report detailed the results. In addition, a separate report was completed that outlined the feasibility of constructing a 4 acre oyster reef in Hillsborough Bay, FL. This report included several construction considerations such as local sources and costs of cultch materials, shipping/transport, staging areas, construction equipment as well as potential local contractors. This paper reports the results of the oyster pilot project and feasibility report as well as lessons learned from each approach.


Africa ◽  
1982 ◽  
Vol 52 (3) ◽  
pp. 77-91 ◽  
Author(s):  
A. P. Cheater

INTRODUCTIONIn 1930 the Land Apportionment Act created freehold areas exclusively for blacks, known as the ‘native purchase areas’. Forty-seven years later these sixty-six separate areas lost their legal identity when the Land Tenure Amendment Act consolidated them, and the formerly ‘European’ commercial farms, into the ‘general area’ distinct from the communally held ‘Tribal Trust Land’. Today, although the new Government has not yet touched Zimbabwe's land law, it has popularized new terms to describe these three categories: ‘rural farmers’ describes the peasantry in the communal lands; ‘small-scale commercial farmers’ locates freeholders in the former African purchase lands; and ‘large-scale commercial farmers’ are those whites– and handful of blacks – who work land in what used to be the ‘European area’. The small-scale commercial farmers, however, remain exclusively black. Thus we can talk of the African purchase lands as if they had not been affected by the Land Tenure Amendment Act of 1977.


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