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A POSSIBLE EFFECT OF SALINITY FLUCTUATION ON ABUNDANCE OF BENTHIC VEGETATION AND ASSOCIATED FAUNA IN NORTHEASTERN FLORIDA BAY

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ESTUARIES 1993年第4期16卷 703-717页

作者： MONTAGUE, CL LEY, JA 1. Systems Ecology Program Department of Environmental Engineering Sciences University of Florida 32611 Gainesville Florida

In southern Florida, a vast network of canals and water control structures mediate freshwater discharge into the coastal zone. Management protocol for one such canal network (C-111) is being modified in part to try to improve habitat for estuarine fish and wading birds in northeastern Florida Bay, an estuarine part of Everglades National Park. Changes in canal management could alter the spatial and temporal salinity regime in the estuary. To better predict the effect of such changes on estuarine habitat, abundances of submersed vegetation and benthic animals were sampled repeatedly at 12 stations that differed in salinity. A variety of other parameters were also measured (nutrients, light, temperature, oxygen, sediment characteristics, and others). Mean salinity among stations ranged from 11.4 parts per thousand to 33.1 parts per thousand. Densities of benthic plants and animals differed among stations by several orders of magnitude. The standard deviation of salinity was the best environmental correlate with mean plant biomass and benthic animal density: less biota occurred at stations with greater fluctuations in salinity. The two stations with the least plant biomass also had the highest mean water temperatures. In a stepwise multiple regression analysis, standard deviation of salinity accounted for 59% of the variation in the logarithm of mean plant biomass among stations. For every 3 parts per thousand increase in the standard deviation, total benthic plant biomass decreased by an order of magnitude. Mean water temperature accounted for only 14% of the variation, and mean salinity was not included for lack of significance. At stations with widely fluctuating salinities, not only was biomass low, but species dominance also frequently changed. Severe fluctuation in salinity may have prevented abundant benthos by causing physiological stress that reduced growth and survival. Salinity may not have remained within the range of tolerance of any one plant species for

关键词： Salinity Biomass Plants Benthic plants Vegetation Animals Standard deviation Sediments Phosphorus Water temperature

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systems methodology and framework for problem definition in Mobile ad hoc networks

Systems methodology and framework for problem definition in ...

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2008 IEEE International systems Conference Proceedings, SysCon 2008

作者： Anguswamy, Reghu Thiagarajan, Maheswaran Dagli, Cihan H. Systems Engineering Program Department of Engineering Management and Systems Engineering Missouri University of Science and Technology Rolla MO 65401 United States Systems Engineering Graduate Program Department of Engineering Management and Systems Engineering Missouri University of Science and Technology Rolla MO 65401 United States

ISBN: (纸本)9781424421503

Mobile Ad Hoc Networks are communication networks built up of a collection of mobile devices which can communicate through wireless connections. Mobile Ad Hoc Networks have many challenges such as routing, which is the task of directing data packets from a source node to a given destination. This task is particularly hard in Mobile Ad Hoc Networks: due to the mobility of the network elements and the lack of central control, robustness and adaptability in routing algorithms and work in a decentralized and self organizing way. Through the principles of systems architecting and engineering, the problem statement in Mobile Ad Hoc Networks could be defined more specifically and accurately. The uncertainties and techniques for mitigating and even taking positive advantages of them can be achieved through a framework of uncertainties as in [1]. The systems methodology framework called Total systems Intervention (TSI) described by Flood and Jackson [2] select a systems methodology for Mobile Ad Hoc Networks. The purpose of this paper is to show how TSl when integrated with a framework created to understand the risks and opportunities can help develop strategies to minimize the risks and to take advantage of the opportunities for facing challenges in Mobile Ad Hoc Networks. ©2008 IEEE.

关键词： Mobile ad hoc networks

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Analysis of Security Vulnerabilities and Countermeasures of Ethernet Passive Optical Network(EPON)

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China Communications 2007年第3期4卷 17-29页

作者： Stamatios V.Kartalopoulos Pramode K.Verma School of Electrical and Computer Engineering Telecommunications Systems Program University of Oklahoma-Tulsa Tulsa OK 74135 USA

Ethernet-based Passive Optical Network(EPON) is considered a very promising solution for the first mile problem of the next generation *** to its particular characteristic of shared media structure,EPON suffers many security vulnerabilities. Communication security must be guaranteed when EPON is applied in *** paper gives a general introduction to the EPON system,analyzes the potential threats and attacks pertaining to the EPON system,and presents effective countermea-sures against these threats and attacks with emphasis on the authentication protocols and key distribution.

关键词： EPON security vulnerabilities attacks countermeasures authentication protocols key distribution

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Meteorological data implications modeling on evapotranspiration variability in arid and semi-arid zones in Saudi Arabia using hybrid metaheuristic

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Scientific Reports 2025年第1期15卷 1-22页

作者： Noureddine, Oulad Naoui Mohamed, Sekkoum El Amine, Cherif Alzaed, Ali Gedfew, Meseret Abeje Ghoneim, Sherif S. M. Hussein, Enas E. Materials Energy Systems Technology and Environment Laboratory Department of Hydraulic and Civil Engineering University Ghardaia Bounoura Algeria Department of Civil Engineering Faculty of Civil Engineering and Architecture Amar Telidji University P. O. Box 37.G Laghouat 03000 Algeria Water Management and Treatment Laboratory University of Science and Technology of Oran Mohamed Boudiaf B.P. 1505 El M’Naouer Oran Algeria Architectural Engineering Program - Civil Engineering Department Faculty of Engineering Taif University Taif 21944 Saudi Arabia Department of Civil Engineering Faculty of Technology Debre Markos University P. O. Box 269 Debre Markos Ethiopia Department of Electrical Engineering College of Engineering Taif University Taif 21944 Saudi Arabia Water Management Research Institute National Water Research Center Shubra El-Kheima 13411 Egypt

This work is unique and contributes new knowledge to the field whereas it involves introducing a new method based on coupling two or three stochastic models, analyzing new data represented by drought and flooding risk relationship, and addressing a previously unexplored research question: Can we make a decision regarding future evapotranspiration-flooding risk relationship? In this paper, the Bat algorithm (BAT) with the Newton Method (NM), Bird Swarm Algorithm (BSA), Genetic Algorithm (GA), and Chicken Swarm Optimization Algorithm (CSO) are used as a hybrid model in arid and semi-arid zones in Saudi Arabia as well as for modeling rainfall, temperature, and solar radiation implications on evapotranspiration variability. Coupling between aridity and evapotranspiration over a long time can create flooding risks. This holistic modeling aims to reduce flooding risks and ensure the desired decision. Several models were employed to simulate some basins’ Potential and Actual evapotranspiration as case studies. The meteorological inputs of the hybrid models were calibrated and validated with metric evaluation for input and output of evapotranspiration, respectively. The results suggest that the application of a hybrid model can improve the accuracy of evapotranspiration simulations in terms of statistical parameters, whereas BAT–GA–NM reduced MAPE from 38.88 to 4.16% for Mekkah and from 14.94 to 2.04% for Medina and NSCE from − 0.17 to 0.97 for Mekkah and from 0.82 to 0.99%. Those parameters will provide a better understanding of evapotranspiration processes in watersheds and valuable information for early warnings of flooding risks. © The Author(s) 2025.

关键词： Evapotranspiration Hybrid metaheuristic Modeling Rainfall Solar radiation data Temperature

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THE NEXT-GENERATION IN UNDERWATER ACOUSTIC DETECTION

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AT&T TECHNICAL JOURNAL 1995年第4期74卷 4-15页

作者： EICKMEYER, JR EPTING, BE THOMPSON, MV Undersea Systems Engineering Department at AT&T Advanced Technology Systems in Whippany New Jersey Fixed Distributed System-Underwater Segment (FDS-UWS) program at AT&T Advanced Technology Systems in Greensboro North Carolina Undersea Systems Engineering Department at AT&T Bell Laboratories in Whippany New Jersey

Since the 1950s, AT&T has provided underwater detection equipment to the U.S. Navy to satisfy the navy's two-tier mission of studying the ocean and developing and testing sonar systems. The latest generation of hardware is a fiber-optic system that has the transmission capacity of all the previous systems combined. Its design and development has provided a challenge both from the technical aspect of meeting stringent performance requirements and from the engineering aspect of managing a large defense program having a budget greater than $500 million. Following a brief summary of AT&T's history in the development and manufacture of underwater acoustic detection hardware, this paper provides a technical description of the fiber-optic system and a project history describing the processes used in bringing the equipment into production. During the period of program execution (1989 to the present), systems engineering management philosophy has evolved from strict now-down of requirements via military standards to concurrent engineering and product-realization teams. The Fixed Distributed System (FDS) project has followed the same route, partly by design and partly by necessity. It provided some valuable lessons that have been learned and incorporated into the present AT&T Advanced Technology systems (ATS) engineering process, which has been the basis for AT&T Best Current Practices in systems engineering.

关键词： Underwater acoustics

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Discovery of rare association rules in the distribution of lawsuits in the federal justice system of Southern Brazil

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International Journal of Business Intelligence and Data Mining 2021年第2期18卷 127-154页

作者： dos Santos Gruginskie, Lúcia Adriana Roehe Vaccaro, Guilherme Luís Chiwiacowsky, Leonardo Dagnino Blesz, Attila Elod Graduate Program in Production Engineering and Systems Unisinos Sao Leopoldo RS Brazil Program in Industrial Engineering UCS-Universidade de Caxias do Sul Bento Gonçalves City RS Brazil

In the context of data mining, infrequent association rules may be beneficial for analysing rare or extreme cases with very low support values and high confidence. In researching risky situations or allocating specific resources, such rules may have a much greater impact than rules with high support value. The objective of this study is to obtain association rules from the database of lawsuits filed in the Federal Court of Southern Brazil in 2016, including both frequent and rare rules. By finding these rules, especially rare ones, the information collected can assist in the decision-making process, in this case, such as training clerks or establishing specialised courts. Copyright © 2021 Inderscience Enterprises Ltd.

关键词： Association rules

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Spreading systems engineering and engineering management know-how across capstone design: A comparison of an existing course to a pilot 122

Spreading systems engineering and engineering management kno...

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2015 122nd ASEE Annual Conference and Exposition

作者： Abel, Kate D. Bachelor of Engineering in Engineering Management Program School of Systems and Enterprises United States

About a decade ago, a movement was started at Stevens Institute of Technology to infuse the Capstone experience with systems engineering (SE) and engineering Management (EM) knowledge. However the discipline specific Senior Design advisors did not have the time to teach, nor the in-depth awareness of, SE and EM topics to be able to provide their students with substantive learning on these subjects. A course soon emerged that would run along side the Senior Capstone Design course, to provide knowledge in these areas. The course exists in two formats. One format has been running for years as a traditional 3-credit, one semester course. The other format was implemented recently as a pilot to provide just-in-time learning over both semesters of senior design. Both formats have been running concurrently for three years. This article will address how the needs of the Senior Design Advisors from the various disciplines were married to systems engineering and engineering Management topics and deliverables to create two versions of a course to improve the overall functionality of all Capstone design teams, as well as, their project's final outcome. To conclude, the benefits/disbenefits and success/lack of success of the two different formats is highlighted. © American Society for engineering Education, 2015.

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Non-contacting interfaces: A case study in modular spacecraft design

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systems Research Forum 2007年第1期2卷 27-34页

作者： Butail, Sachit Peck, Mason Mechanical Engineering from Delhi College of Engineering Delhi University India Cornell's Sibley School of Mechanical and Aerospace Engineering Cornell's Systems Engineering Program United Kingdom

The benefits of modularization, such as reusability and upgradeability, remain underutilized in space. Exploiting these advantages after a spacecraft is launched introduces too much cost and risk in the current paradigm of spacesystem design. This gap between modular design and its benefi ts has inspired us to focus attention on interfaces. Many of the obstacles to bridging this gap lie in mechanical attachment of spacecraft subsystems. This paper reexamines the function of mechanical interfaces among spacecraft components and describes a new realization in which flux-pinning superconductors and permanent magnets provide stable, but unpowered, connections among spacecraft components that appear to hover at some distance from one another. Beginning with functional abstraction, this study identifies a new set of unexploited possibilities that add versatility to space-systems architectures. First, the limitations imposed on modularity due to mechanical coupling in spacecraft architecture are identified. These limitations are then used to back out the requirements for a non-contacting interface. With several technologies that enable adhesion without mechanical contact identified, requirements flowdown and functional analysis is performed to quantify technical performance measures for the interface. © 2007 World Scientific Publishing Company.

关键词： Reusability

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Fragility of oil as a critical infrastructure

Fragility of oil as a critical infrastructure

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33rd Annual International Conference of the American Society for engineering Management 2012, ASEM 2012 - Agile Management: Embracing Change and Uncertainty in engineering Management

作者： Jaradat, Raed Katina, Polinpapilinho F. Gheorghe, Adrian Old Dominion University Engineering Management and Systems Engineering Program United States

ISBN: (纸本)9781627482820

Interdependency among critical infrastructure (CI) is an increasing phenomenon. The 21st century has been defined by events that have changed individuals' perceptions of what CI is and its risks and vulnerabilities. One of the major critical infrastructures is the energy sector as described by public policy, and oil is an important component of this sector. This paper explores the relationships between oil and other infrastructures. We argue that the relationship between oil and other systems has changed the structure of the oil industry. How to manage this new structure is an emerging issue that requires attention from a systems approach. Whether oil is in its crude form or refined form, its value cannot be minimized due to its various applications. Oil and its derivatives are not an independent infrastructure;they are interconnected to other forms of energy and other infrastructures. These interconnections have increased risk and vulnerability from hostile nations, terrorists, criminals, and incompetent operators. We conclude that oil is critical to the well-being of humanity and yet is so fragile that it can be affected by cascading events from other critical infrastructure due coupling and pervasive computing technologies. Copyright, American Society for engineering Management, 2012.

关键词： Critical infrastructures

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The University of Houston Electric Energy systems Control program

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IEEE Transactions on Education 1978年第3期21卷 197-202页

作者： Tacker, Edgar C. Lee, Kwang Yun Linton, Thomas D. Sanders, Charles W. Department of Electrical Engineering and Systems Engineering Program University of Houston Houston TX 77004 United States

This paper presents our response to the national need to educate more students in the area of power systems engineering. Our Electric Energy systems Control program (EESCP) is described, both in terms of (1) individual courses, sequences of courses, and subprograms of concentration, and (2) the development of the Electric Energy System Control Laboratory Facility (EESCL). The description is organized so as to emphasize the close relationships between the particular EESCL equipment purchased and the development of the individual courses. The present status of the EESCP program development is given as is an assessment of our progress measured against our educational objectives. Discussion is also provided relative to our future plans in further developing our educational program in power systems education. Copyright © 1978 by The Institute of Electrical and Electronics Engineers, Inc.

关键词： Power systems Energy management Microcomputers Electromechanical systems Digital control Cathode ray tubes

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