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Population dynamics of the tropical oyster Magallana bilineata(Mollusca,Bivalvia,Ostreidae)in Mengkabong Bay,Tuaran,Malaysia

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Aquaculture and Fisheries 2024年第2期9卷 295-305页

作者： Joanna W.Doinsing Julian Ransangan Politeknik Sandakan Sabah Education HubBatu 10Jalan Sungai BatangSandakanSabah90000Malaysia Borneo Marine Research Institute Universiti Malaysia SabahJalan UMSKota Kinabalu88400Malaysia

Knowledge about the population dynamics within a specific spatial area is vital for the effective planning and management of important fishery resources.Population parameters,including the asymptotic length(L∞),growth coefficient(K),mortalities(Z,F,and M),recruitment pattern,exploitation level(E),and yield per recruit(Y’/R),of the tropical oyster Magallana bilineata in Mengkabong Bay,Tuaran,Malaysia were analyzed by using the FiSAT software,using on the monthly shell length-frequency data collected from April 2019 to March 2020.A total of 435 oysters with shell lengths ranging from 3.64 to 11.16 cm were analyzed.Habitat water temperature,salinity,dissolved oxygen,hydrogen ion concentration(pH),and chlorophyll concentration were measured at 29.0-33.7◦C,26.68-35.74 psμ,3.18-6.99 mg/L,6.57-8.29 and 1.51-98.93μg/L,respectively.The logarithmic relationship between the length and weight of Log W=1.9055 Log L+0.1049(R2=0.5431)with exponent b of 1.9055 for combined sexes showed a negative allometric growth(b<3),indicating that the oysters in Mengkabong Bay are skinny.Several management measures have been proposed to promote high meat growth,including the use of genetically selected seeds,selection of new farming sites and adoption of grow-out methods that favour high meat growth.Asymptotic length(L∞)and growth coefficient(K)of the von Bertalanffy Growth Formula(VBGF)for M.bilineata were estimated at 12.13 cm and 1.00 yr􀀀1,respectively.The theoretical ages at length zero(t0)(0.0487)were estimated by substituting L∞and K in Pauly’s equation.The sizes attained by M.bilineata were 3.76,5.04,6.13,7.05,7.83,and 8.49 cm at the end of 2,4,6,8,10,and 12 months,respectively.The calculated growth performance index(φ)for M.bilineata in Mengkabong Bay was 2.168,while the estimated lifespan was 3 years.The recruitment pattern was observed year-round,with higher recruitment activities in September-October 2019 and January 2020.The total mortality(Z)was analyzed using the length-converted catch curve and estimated at 3.04 yr^(-1),fishin

关键词： Crassostrea iredalei Length-weight relationship Growth parameters Recruitment exploitation

Drilling and completion technologies of coalbed methane exploitation: an overview

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International Journal of Coal Science & Technology 2022年第5期9卷 1-31页

作者： Tianshou Ma Jinhua Liu Jianhong Fu Bisheng Wu State Key Laboratory of Oil and Gas Reservoir Geology and exploitation Southwest Petroleum UniversityChengdu 610500SichuanChina State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

Coalbed methane(CBM)drilling and completion technologies(DCTs)are signifcant basis for achieving efcient CBM exploration and exploitation.Characteristics of CBM reservoirs vary in diferent regions around the world,thereby,it is crucial to develop,select and apply the optimum DCTs for each diferent CBM reservoir.This paper frstly reviews the development history of CBM DCTs throughout worldwide and clarifes its overall development tendency.Secondly,diferent well types and its characteristics of CBM exploitation are summarized,and main application scopes of these well types are also discussed.Then,the key technologies of CBM drilling(directional drilling tools,measurement while drilling,geo-steering drilling,magnetic guidance drilling,underbalanced drilling and drilling fuids),and the key technologies of CBM completion(open-hole,cavity and under-ream completion,cased-hole completion,screen pipe completion and horizontal well completion)are summarized and analyzed,it is found that safe,economic and efcient development of CBM is inseparable from the support of advanced technologies.Finally,based on the current status of CBM development,the achievements,existing challenges and future prospects are summarized and discussed from the perspective of CBM DCTs.

关键词： Coalbed methane CBM exploitation Drilling Completion Horizontal well L/U/V-shaped well Multilateral well

Frilled Lizard Optimization: A Novel Bio-Inspired Optimizer for Solving Engineering Applications

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Computers, Materials & Continua 2024年第6期79卷 3631-3678页

作者： Ibraheem Abu Falahah Osama Al-Baik Saleh Alomari Gulnara Bektemyssova Saikat Gochhait Irina Leonova OmParkash Malik Frank Werner Mohammad Dehghani Department of Mathematics Faculty of ScienceThe Hashemite UniversityP.O.Box 330127Zarqa13133Jordan Department of Software Engineering Al-Ahliyya Amman UniversityAmman19328Jordan Faculty of Science and Information Technology Software EngineeringJadara UniversityIrbid21110Jordan Department of Computer Engineering International Information Technology UniversityAlmaty050000Kazakhstan Symbiosis Institute of Digital and Telecom Management Constituent of Symbiosis International Deemed UniversityPune412115India Neuroscience Research Institute Samara State Medical UniversitySamara443001Russia Faculty of Social Sciences Lobachevsky UniversityNizhny Novgorod603950Russia Department of Electrical and Software Engineering University of CalgaryCalgaryAB T2N 1N4Canada Faculty of Mathematics Otto-von-Guericke UniversityP.O.Box 4120Magdeburg39016Germany Department of Electrical and Electronics Engineering Shiraz University of TechnologyShiraz***Iran

This research presents a novel nature-inspired metaheuristic algorithm called Frilled Lizard Optimization(FLO),which emulates the unique hunting behavior of frilled lizards in their natural habitat.FLO draws its inspiration from the sit-and-wait hunting strategy of these lizards.The algorithm’s core principles are meticulously detailed and mathematically structured into two distinct phases:(i)an exploration phase,which mimics the lizard’s sudden attack on its prey,and(ii)an exploitation phase,which simulates the lizard’s retreat to the treetops after feeding.To assess FLO’s efficacy in addressing optimization problems,its performance is rigorously tested on fifty-two standard benchmark functions.These functions include unimodal,high-dimensional multimodal,and fixed-dimensional multimodal functions,as well as the challenging CEC 2017 test suite.FLO’s performance is benchmarked against twelve established metaheuristic algorithms,providing a comprehensive comparative analysis.The simulation results demonstrate that FLO excels in both exploration and exploitation,effectively balancing these two critical aspects throughout the search process.This balanced approach enables FLO to outperform several competing algorithms in numerous test cases.Additionally,FLO is applied to twenty-two constrained optimization problems from the CEC 2011 test suite and four complex engineering design problems,further validating its robustness and versatility in solving real-world optimization challenges.Overall,the study highlights FLO’s superior performance and its potential as a powerful tool for tackling a wide range of optimization problems.

关键词： Optimization engineering bio-inspired metaheuristic frilled lizard exploration exploitation

A Graph-Based Reinforcement Learning Method with Converged State Exploration and exploitation

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Computer Modeling in Engineering & Sciences 2019年第2期118卷 253-274页

作者： Han Li Tianding Chen Hualiang Teng Yingtao Jiang College of Mathematics Physics and Electronic Information EngineeringWenzhou UniversityWenzhouZhejiang325035China School of Physics and Information Engineering Minnan Normal UniversityZhangzhouFujian363000China Department of Civil and Environmental Engineering Howard R.Hughes College of EngineeringUniversity of NevadaLas VegasNV454015USA Department of Electrical and Computer Engineering Howard R.Hughes College of EngineeringUniversity of NevadaLas VegasNV454015USA.

In any classical value-based reinforcement learning method,an agent,despite of its continuous interactions with the environment,is yet unable to quickly generate a complete and independent description of the entire environment,leaving the learning method to struggle with a difficult dilemma of choosing between the two tasks,namely exploration and exploitation.This problem becomes more pronounced when the agent has to deal with a dynamic environment,of which the configuration and/or parameters are constantly changing.In this paper,this problem is approached by first mapping a reinforcement learning scheme to a directed graph,and the set that contains all the states already explored shall continue to be exploited in the context of such a graph.We have proved that the two tasks of exploration and exploitation eventually converge in the decision-making process,and thus,there is no need to face the exploration vs.exploitation tradeoff as all the existing reinforcement learning methods do.Rather this observation indicates that a reinforcement learning scheme is essentially the same as searching for the shortest path in a dynamic environment,which is readily tackled by a modified Floyd-Warshall algorithm as proposed in the paper.The experimental results have confirmed that the proposed graph-based reinforcement learning algorithm has significantly higher performance than both standard Q-learning algorithm and improved Q-learning algorithm in solving mazes,rendering it an algorithm of choice in applications involving dynamic environments.

关键词： Reinforcement learning graph exploration and exploitation maze.

Study on the groundwater exploitation test in the Yellow River lower reaches——Acase studyon the north suburb waterworks of Zhengzhou,China

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Science China(Technological Sciences) 2004年第Z1期47卷 14-24页

作者： Gnansounou Raoul College of Environment and Resources Jilin University Changchun 130026 China

This paper presents the studies on groundwater resources potential of the Yellow River (YR) terrace in Zhengzhou area, China. The main aim of the research was to resolve water shortage problems induced by recent but frequent drying ups of the YR in its lower reaches. Geologic explorations and grouped-pumping tests were conducted in the area. Based on collected data a groundwater flow net was established. The buried depth of groundwater level and water bearing potential of the aquifers were evaluated. Conventional method was used to determine recharge of the groundwater by lateral infiltration of the YR in pumping patterns. The results show that the study region has a high water bearing potential and offers conditions for the construction of large water works. However, only limited recharge by lateral infiltration from the river is available when developing large scale groundwater exploitation in the riverside of the YR. Environmental impacts induced by embankment stability of the Great dyke of the YR could be minimized or eliminated by appropriate engineering methods.

关键词： Yellow River lower reaches, groundwater exploitation along river, grouped-pumping test, stability of dyke.

Rational exploitation of Resources and Prevention of Geohazards in Karst Regions

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Acta Geologica Sinica(English Edition) 2001年第3期75卷 239-248页

作者： LU Yaoru Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesZhengding 050803China

This paper discusses the rational exploitation of main resources and prevention of geohazards in karst regions. There exist relationship chains between natural disasters in the earth, which include the chain between geological hazards and climatic hazards, the chain between geological hazards and biogenic hazards as well as the one between geological hazards. Irrational exploitation of all resources will inevitably cause hazards. Therefore it is very important to discuss the problem related to prevention of geohazards by rational exploitation of resources.

关键词： exploitation resources prevention geohazard

Preliminary study on the exploitation plan of the mega hydropower base in the lower reaches of Congo River

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Global Energy Interconnection 2020年第1期3卷 13-23页

作者： Chuanyu Deng Fulong Song Zhengxi Chen Global Energy Interconnection Development and Cooperation Organization No.8 Xuanwumennei StreetBeijing 100031P.R.China PowerChina Chengdu Engineering Corporation Limited No.1 Huanhuabei StreetChengdu 610072P.R.China

There have been few studies on the hydropower exploitation plan for sections beyond the Inga hydropower project(HPP)in the lower reaches of the Congo River.Based on topographic and hydrological data of the basin,the exploitation plan for the lower reaches of the Congo River is herein studied.The preliminary proposal involves exploitation using three-cascade hydropower stations.The Grand Inga HPP is the core of the mega hydropower base.The full supply level(FSL)of the reservoir,installed capacity,and regulation performance of the Grand Inga HPP are studied in detail.The main advantages and disadvantages of the high and low dam schemes of the Grand Inga Hydropower Project are compared,in addition to their effects on the overall development of the hydropower base.Moreover,the installed capacity is optimized based on the load characteristics.Based on simulation of cascade hydropower operation and comprehensive analysis,the project scale and implementation sequence is proposed.The influence of hydropower on socio-economic development,energy supply,and emission reduction is analyzed.Finally,the optimal exploitation scheme of the mega hydropower base for the lower reaches of the Congo River is proposed.

关键词： Congo River Cascade hydropower exploitation plan Grand Inga hydropower project Mega hydropower base Scheme optimization

Compari ng the con figured causal antecedents of exploration and exploitation: a fuzzy set qualitative comparative analysis

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Frontiers of Business Research in China 2019年第1期13卷 53-77页

作者： Lulu Liu Fengbin Wang Xiukun Li Renmin Business School Renmin University of China Beijing 100872 China Renmin Business School Renmin University of China Beijing 100872 China

Although exploration and exploitation, as a pair of paradoxical organizational outcomes, are generated by different causal conditions, the conjunction of their respective causal antecedents has yet to be fully examined. Combining environmental uncertainty, unit interdependence, entrepreneurial bricolage and firm life cycle stage in a qualitative comparative analysis (QCA), the distinct causal configurations of exploration and exploitation are formalized and compared based on a survey of founders or high-level managers in 63 small firms. Results show that contrasted relationships between entrepreneurial bricolage and unit interdependenee exist in that the two antecedents are partial substitutes in exploration whereas they are complements in exploitation when combined with other conditions. This study provides empirical evidence on the causal configurations of exploration and exploitation and deepens our current understanding of ambidexterity.

关键词： Exploration exploitation Ambidexterity Configuration Qualitative comparative analysis (QCA) Environmental uncertainty Entrepreneurial bricolage Unit interdepe ndence

CHARACTERISTICS AND RATIONAL exploitation OF LAND RESOURCES IN XIZANG

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Chinese Geographical Science 1996年第4期6卷 321-331页

作者： Li Mingsen (Commission for Integrated Survey of Natural Resources,the Chinese Academy of Sciences, Beijing 100101, PRC) Commission for Integrated Survey of Natural Resources the Chinese Academy of Sciences Beijing PRC

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关键词： land resources productive potentiality Xizang land exploitation