Assessing the Fisheries and Ecosystem Structure of the Largest Greek Lake (Lake Trichonis)

An Ecopath with Ecosim (EwE) modeling approach was used to explore the ecological structure of the largest lake in Greece (Lake Trichonis). Until the mid-1990s, the lake was receiving a high level of pollution and the fishing pressure was intense, while since the early 2000s, fisheries and other human pressures gradually declined. Nowadays, the lake’s fisheries mainly target Atherina boyeri due to the absence of market demand for the other fish species in the lake, resulting in a low overall fisheries pressure on the fish stocks. The model was built with data collected through: (a) field samplings, (b) in-depth targeted interviews of professional fishermen and (c) historical archive information. The model considered 22 functional groups, while fishing activities were represented by three classes according to the used gears. The outputs of the model revealed that the ecosystem is dominated by low trophic level species (also identified as keystone species), indicating the significance of bottom-up control in the regulation of food web processes. Ecological indicators depicted that the lake’s ecosystem is mature and resilient to external disturbances. The methodological approach used in this study was shown to be helpful for studies addressing ecosystem structure, in particular with limited data availability.

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Regional Bicycle Network Evaluation and Strategic Planning: A Quantitative Methodological Approach Despite Limited Data Sources for Cycling

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/03611981211028870 ◽

2021 ◽

pp. 036119812110288

Author(s):

Alex van Dulmen ◽

Martin Fellendorf

Keyword(s):

Travel Demand ◽

Choice Model ◽

Methodological Approach ◽

Data Availability ◽

Data Sources ◽

Test Case ◽

Demand Model ◽

Limited Data ◽

Demand Models ◽

Bicycle Infrastructure

In cases where budgets and space are limited, the realization of new bicycle infrastructure is often hard, as an evaluation of the existing network or the benefits of new investments is rarely possible. Travel demand models can offer a tool to support decision makers, but because of limited data availability for cycling, the validity of the demand estimation and trip assignment are often questionable. This paper presents a quantitative method to evaluate a bicycle network and plan strategic improvements, despite limited data sources for cycling. The proposed method is based on a multimodal aggregate travel demand model. Instead of evaluating the effects of network improvements on the modal split as well as link and flow volumes, this method works the other way around. A desired modal share for cycling is set, and the resulting link and flow volumes are the basis for a hypothetical bicycle network that is able to satisfy this demand. The current bicycle network is compared with the hypothetical network, resulting in preferable actions and a ranking based on the importance and potentials to improve the modal share for cycling. Necessary accompanying measures for other transport modes can also be derived using this method. For example, our test case, a city in Austria with 300,000 inhabitants, showed that a shift of short trips in the inner city toward cycling would, without countermeasures, provide capacity for new longer car trips. The proposed method can be applied to existing travel models that already contain a mode choice model.

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Review of archetype development strategies for energy assessment at urban scale

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/855/1/012021 ◽

2021 ◽

Vol 855 (1) ◽

pp. 012021

Author(s):

G M Colleto ◽

V Gomes

Keyword(s):

Energy Use ◽

Policy Design ◽

Methodological Approach ◽

Level Of Detail ◽

Data Availability ◽

Depth Information ◽

Built Environments ◽

Energy Assessment ◽

Operational Energy ◽

High Level

Abstract Understanding the built environment’s impacts is essential to support strategic planning and policy design for sustainable development now, and in the future. Modelling individual buildings and infrastructure at high level of detail is resource intensive. Thus, urban scale analyses demand simplifications that balance level of detail and scope broadness. For combining simplified modelling and extended scope, classification by archetypes emerge as a promising methodological approach to extend assessment scope beyond energy use simulation. Archetypes that include life cycle assessment (LCA) parameters can support circularity challenges diagnosis, mapping and predictions, strategies to close material and energy loops and their monitoring within urban built environments. We hypothesized that, upon limited complementation, operational and pre/post construction (embodied) datasets coupled with building grouping techniques satisfactorily represent the built stock to support cradle to grave LCA of built environments. Studies on the use of archetypes for this purpose are scarce, so this article reports findings of a Systematic Literature Review (SLR) on archetypes-based approaches for energy assessment that could inspire application in LCA studies at urban scale. The SLR highlighted a lack of methodological consensus, and that data availability seems to be the major limitation for archetype creation in most studies, which rarely present in-depth information on their development. The few investigations providing consistent methodological procedures actually detail the initial classification process. Transposing the archetype strategy from energy assessment to LCA at urban scale faces practical limitations. Several databases support operational energy studies, but the same does not apply to LCA. Urban building energy models typically overlook infrastructure. Also, statistical results depend directly on data input quality and data availability may compromise the quality of variable selection.

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Improved Proofs Of Retrievability And Replication For Data Availability In Cloud Storage

The Computer Journal ◽

10.1093/comjnl/bxz151 ◽

2020 ◽

Vol 63 (8) ◽

pp. 1216-1230 ◽

Cited By ~ 2

Author(s):

Wei Guo ◽

Sujuan Qin ◽

Jun Lu ◽

Fei Gao ◽

Zhengping Jin ◽

...

Keyword(s):

Service Providers ◽

Cloud Service ◽

Data Availability ◽

Forgery Attack ◽

Common Strategy ◽

Comparable Performance ◽

Replication Scheme ◽

High Level ◽

Cloud Users ◽

Proofs Of Retrievability

Abstract For a high level of data availability and reliability, a common strategy for cloud service providers is to rely on replication, i.e. storing several replicas onto different servers. To provide cloud users with a strong guarantee that all replicas required by them are actually stored, many multi-replica integrity auditing schemes were proposed. However, most existing solutions are not resource economical since users need to create and upload replicas of their files by themselves. A multi-replica solution called Mirror is presented to overcome the problems, but we find that it is vulnerable to storage saving attack, by which a dishonest provider can considerably save storage costs compared to the costs of storing all the replicas honestly—while still can pass any challenge successfully. In addition, we also find that Mirror is easily subject to substitution attack and forgery attack, which pose new security risks for cloud users. To address the problems, we propose some simple yet effective countermeasures and an improved proofs of retrievability and replication scheme, which can resist the aforesaid attacks and maintain the advantages of Mirror, such as economical bandwidth and efficient verification. Experimental results show that our scheme exhibits comparable performance with Mirror while achieving high security.

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Determining the structure of pharmaceutical industry in Iran

International Journal of Pharmaceutical and Healthcare Marketing ◽

10.1108/ijphm-06-2017-0030 ◽

2019 ◽

Vol 13 (1) ◽

pp. 101-115

Author(s):

Sara Emamgholipour ◽

Lotfali Agheli

Keyword(s):

Pharmaceutical Industry ◽

Economies Of Scale ◽

Monopolistic Competition ◽

Pharmaceutical Market ◽

Data Availability ◽

Market Demand ◽

Firm Level ◽

Content Type ◽

Measure Concentration ◽

Pharmaceutical Industries

Purpose As the pharmaceutical industry is one of the key sectors of the health-care system, the identification of its structure is of particular importance. This paper aims to determine the structure of the pharmaceutical industry in Iran to provide appropriate solutions for pricing and regulation by policymakers. Iran is a growing pharmaceutical market with over $4bn in sales, so the supply side needs to be examined to meet the domestic consumption. Design/methodology/approach This research is a descriptive and retrospective analytical study which examines the Iranian pharmaceutical industry through library studies and using pharmaceutical data of the country’s Food and Drug Administration during 1992-2016. Due to data availability in firm level, the concentration ratio of N leading firms and the Herfindahl–Hirschman index are used to measure the concentration of the pharmaceutical market in 2014 and 2016. Findings The results show that pharmaceutical manufacturing, importing companies and distributing companies play roles in monopolistic competition market, loose oligopoly market and oligopoly market, respectively. For all companies, the magnitudes of Herfindahl–Hirschman indices indicate non-competitive settings. As a result, these companies set their own prices, and market demand affects their sales. In addition, demand for medicines is shaped in the form of supply-induced demand. Research limitations/implications This research was accomplished with no computational limitation. However, it was confined to only one country, one industry and the mentioned period of study. Practical implications The pharmaceutical manufacturers have no influence on medicine prices, and government pricing regulations lessen the market power of such market agents. However, the easy entry to and exit from market stimulate producers to participate in manufacturing activities. The pharmaceutical importers may expand their imports in response to entry new actors; however, the new entrants weaken the coordination on pricing decisions. Social implications As pharmaceutical distributers act in an oligopoly market, they can collude, reduce competition and lower the welfare of pharmaceutical consumers. In such conditions, high investment requirements and economies of scale may discourage the entry of new firms. Originality/value Although there are various studies on market structure in non-pharmaceutical industries, this study is a new effort to measure concentration in the Iranian pharmaceutical market and to determine its structure.

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The Use of Contract Adjustments to Lengthen the CEO Horizon in the Presence of Internal and External Monitoring

Journal of Management Accounting Research ◽

10.2308/jmar-50395 ◽

2013 ◽

Vol 25 (1) ◽

pp. 199-229 ◽

Cited By ~ 5

Author(s):

Shane S. Dikolli ◽

Susan L. Kulp ◽

Karen L. Sedatole

Keyword(s):

Boards Of Directors ◽

Data Availability ◽

Shareholder Rights ◽

Compensation Contracts ◽

Job Change ◽

External Monitoring ◽

Increased Risk ◽

Short Horizon ◽

High Level ◽

A Current

ABSTRACT We investigate whether boards of directors adjust compensation contracts to lengthen a CEO's decision horizon, and if the use of such contract adjustments depends on the levels of external (i.e., shareholder-based) and internal (i.e., board-based) CEO monitoring. Based on insights from the career-concerns literature, we identify short-horizon CEOs as those nearing retirement, at a firm with a current earnings decline or loss, and/or with an impending job change. We find that firms with a CEO identified as having a short-horizon place greater contract weight on forward-looking information. This horizon-lengthening contract adjustment is less pronounced when there is greater external monitoring (i.e., as proxied by a high level of shareholder rights), consistent with the intuition that increased shareholder rights mitigate CEO entrenchment, leading to less myopic decision making, independent of a contract adjustment. However, we also find that the horizon-lengthening contract adjustment is more pronounced when there is greater internal monitoring (i.e., as proxied by characteristics of the board), consistent with the intuition that increased employment risk from more intense internal monitoring itself creates a demand for increased incentive weights as a means of compensating the CEO for the increased risk. Data Availability: Data used for this study are derived from publicly available databases and proxy statements. JEL Classifications: M52; M41; J33.

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A Globally Consistent Stress Testing Approach

Research in Economics and Management ◽

10.22158/rem.v4n3p153 ◽

2019 ◽

Vol 4 (3) ◽

pp. p153

Author(s):

Colin Ellis

Keyword(s):

Stress Testing ◽

Expected Shortfall ◽

Data Availability ◽

Rank Ordering ◽

Testing Approach ◽

Bank Solvency ◽

High Level ◽

Loan Losses ◽

Compare And Contrast ◽

Expected Outcomes

This paper describes an approach for stress testing banks that is consistent across economies and geographies, in contrast to common “macro scenario” driven approaches. The latter would require economic scenarios to be both equally likely (in a probabilistic sense) and equally stressful (in a conditional loss sense) across countries in order to be comparable. The paper proposes a three-pronged approach for stressing bank solvency, which incorporates recalibrating pre-crisis Basel capital assumptions, adapting the BIS “expected shortfall” approach for securities, and using granular data for income haircuts. Loan losses are quantified using a simple “multiples” approach, starting from expected outcomes, which is derived from the pre-crisis Basel technical proposal. The approach is practical, can be more granular or conducted at a high level, depending on data availability, and offers a simple way for regulators, investors or risk assessors to compare and contrast stresses in different banking systems. Of the eight bank defaults recorded globally during 2017, this approach would have given a better “rank ordering” for seven of them, indicating the approach adds value to traditional solvency metrics.

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A new attempt to discover the covert recognition of faces

Experimental Psychology (Russia) ◽

10.17759/exppsy.2015080404 ◽

2015 ◽

Vol 8 (4) ◽

pp. 45-60

Author(s):

B.G. Meshcheryakov ◽

A.I. Nazarov ◽

L.G. Chesnokova ◽

D.V. Yushchenkova

Keyword(s):

Methodological Approach ◽

False Alarms ◽

Group Level ◽

Short Term ◽

Mean Values ◽

Short Term Exposure ◽

The One ◽

Masking Stimulus ◽

High Level ◽

Unfamiliar Faces

The article describes an experiment which used a new methodological approach to the study of covert recognition of faces by means of registration electro-dermal activity under short-term exposure of familiar and unfamiliar faces and the backward facelike masking stimulus. In contrast to previous studies the control of stimulus awareness allows us to evaluate not just the correct recognitions, but false alarms too. We used as the familiar faces not faces of the well-known persons, but faces of persons from the inner circle of subjects, including the subject’s own face. We confirmed the hypothesis that the characteristics of the electro-dermal reactions in response to familiar and unfamiliar faces will not be different in subjects with a high level of false alarms. However, for the group of subjects with practically zero false alarm rate and zero discriminability of familiar and unfamiliar faces an analysis of electro-dermal reactions have been mixed. On the one hand, as analysis on a group level showed, nor electrocutaneous reactions frequency, nor their amplitudes were not significantly different for the familiar and unfamiliar faces. On the other hand, it is clearly that these individual median and mean values of the amplitudes of subject's reactions are in average more than 2 times stronger when viewed familiar faces than viewed unfamiliar ones. These results leave a good chance to prove the effect of covert identification of faces in further experimentation with other groups of subjects

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Evaluating the role of deterioration models for condition assessment of sewers

Journal of Hydroinformatics ◽

10.2166/hydro.2015.122 ◽

2015 ◽

Vol 17 (5) ◽

pp. 789-804 ◽

Cited By ~ 18

Author(s):

Marius Møller Rokstad ◽

Rita Maria Ugarelli

Keyword(s):

Failure Modes ◽

Structural Condition ◽

Data Availability ◽

Limited Data ◽

Sewer Pipes ◽

Explanatory Variables ◽

Deterioration Model ◽

Sewer Rehabilitation ◽

Inspection Data

Ensuring reliable structural condition of sewers is an important criterion for sewer rehabilitation decisions. Deterioration models applied to sewer pipes support the rehabilitation planning by means of prioritising pipes according to their current and predicted structural status. There is a benefit in applying such models if sufficient inspection data for calibration, an appropriate deterioration model, and adequate covariates to explain the variability in the conditions are available. In this paper it is discussed up to what level the application of sewer deterioration models can be beneficial under limited data availability. The findings show that the indirect nature of the explanatory covariates which are commonly used in sewer deterioration models makes it difficult to harness any benefit from modelling sewer conditions at a network level, but that the deterioration model application still may be beneficial for prioritising inspection candidates. The prediction power of the current sewer deterioration models is limited by the adequacy of the explanatory variables available, and by the fact that different failure modes are mixed in the aggregated condition class, and not modelled explicitly.

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