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The inventory of the carbon stocks in sub tropical forests of Pakistanfor reporting under Kyoto Protocol 被引量:5
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作者 Syed Moazzam Nizami 《Journal of Forestry Research》 SCIE CAS CSCD 2012年第3期377-384,共8页
The United Nations Framework Convention on Climate Change (UNFCCC) requires reporting net carbon stock changes and anthropogenic greenhouse gas emissions, including those related to forests. This paper describes the... The United Nations Framework Convention on Climate Change (UNFCCC) requires reporting net carbon stock changes and anthropogenic greenhouse gas emissions, including those related to forests. This paper describes the status of carbon stocks in sub tropical forests of Pakistan. There are two major sub types in subtropical forests of Pakistan viz a viz Subtropical Chir Pine and Subtropical broadleaved forests. A network of sample plots was laid out in four selected site. Two sites were selected from sub tropical Chir Pine (Pinus roxburghii) forests and two from Subtropical broadleaved forests. Measurement and data acquisition protocols were developed specifically for the inventory car- ried out from 2005 to 2010. In total 261 plots (each of lha.) were established. Estimation of diameter, basal area, height, volume and biomass was carried out to estimate carbon stocks in each of the four carbon pools of above- and below-ground live biomass. Soil carbon stocks were also determined by doing soil sampling. In mature (-100 years old) pine forest stand at Ghoragali and Lehterar sites, a mean basal area of 30.38 and 26.11 m2.ha-1 represented mean volume of 243 and 197 m3·ha-1, respectively. The average biomass (t.ha-1) was 237 in Ghoragali site and 186 tha-1 in Lehterar site, which is equal to 128 and 100 t·ha-1 including soil C. However, on average basis both the forests have 114.5± 2.26 t.ha-1 of carbon stock which comprises of 92% in tree biomass and only 8% in the top soils. In mixed broadleaved evergreen forests a mean basal area (m2.ha-1)was 3.06 at Kherimurat with stem volume of 12.86 and 2.65 at Sohawa with stem volume of 11.40 m3.ha-1. The average upper and under storey biomass (t·ha-1) was 50.93 in Kherimurat site and 40.43 t.ha-1 in Sohawa site, which is equal to 31.18 and 24.36 t ·ha-1 including soil C stocks. This study provides a protocol monitoring biomass and carbon stocks and valuable baseline data for in Pakistan's managed and unmanaged sub-tropical forests. 展开更多
关键词 carbon stock models managed and unmanaged subtropical forests above and below ground biomass forest inventory and volume.
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A stock assessment for Illex argentinus in Southwest Atlantic using an environmentally dependent surplus production model 被引量:3
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作者 WANG Jintao CHEN Xinjun +1 位作者 Kevin W.Staples CHEN Yong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第2期94-101,共8页
The southern Patagonian stock(SPS) of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role... The southern Patagonian stock(SPS) of Argentinian shortfin squid, Illex argentinus, is an economically important squid fishery in the Southwest Atlantic. Environmental conditions in the region play an important role in regulating the population dynamics of the I. argentinus population. This study develops an environmentally dependent surplus production(EDSP) model to evaluate the stock abundance of I. argentines during the period of 2000 to 2010. The environmental factors(favorable spawning habitat areas with sea surface temperature of 16–18°C) were assumed to be closely associated with carrying capacity(K) in the EDSP model. Deviance Information Criterion(DIC) values suggest that the estimated EDSP model with environmental factors fits the data better than a Schaefer surplus model without environmental factors under uniform and normal scenarios.The EDSP model estimated a maximum sustainable yield(MSY) from 351 600 t to 685 100 t and a biomass from 1 322 400 t to1 803 000 t. The fishing mortality coefficient of I. argentinus from 2000 to 2010 was smaller than the values of F(0.1) and F(MSY). Furthermore, the time series biomass plot of I. argentinus from 2000 to 2010 shows that the biomass of I.argentinus and this fishery were in a good state and not presently experiencing overfishing. This study suggests that the environmental conditions of the habitat should be considered within squid stock assessment and management. 展开更多
关键词 Illex argentinus stock assessment Schaefer surplus production model environmental factors Southwest Atlantic
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Analysis of Nuclear Power Plant Fittings Stock Management and Design of a Decision Support System
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作者 WANG Lin, ZHANG Jin long College of Management, Huazhong University of Science & Technology, Wuhan 430074, P.R.China 《International Journal of Plant Engineering and Management》 2002年第4期204-209,共6页
Through analyzing the desired characteristics of fittings in a nuclear power plant, the representative random stock models are built, and forecast methods about the desired probability of fittings are discussed secon... Through analyzing the desired characteristics of fittings in a nuclear power plant, the representative random stock models are built, and forecast methods about the desired probability of fittings are discussed secondly, the design of the plant fittings stock decision support system (FSDSS) is given. Then the main features of this system and function modules are introduced, and the special emphasis on organization of a database and composition and memory of a model base is given. 展开更多
关键词 plant fitings stock model decision support system
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Quantitative Stock Selection Model Based on Long-Short Term Memory(LSTM)Neural Network
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作者 Xiao Wu Yanqiu Tang 《Proceedings of Business and Economic Studies》 2021年第3期19-24,共6页
This article attempted to construct a multi-factor quantitative stock selection model,analyze the financial indicators and transaction data of listed companies in detail via the big data statistical test method,and to... This article attempted to construct a multi-factor quantitative stock selection model,analyze the financial indicators and transaction data of listed companies in detail via the big data statistical test method,and to find out the alpha excess return relative to the market in the case of short stock index futures as a hedge in the Chinese market. 展开更多
关键词 Multi-factor Validity test stock selection model Quantitative strategy
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Chinese prototype building models for simulating the energy performance of the nationwide building stock 被引量:1
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作者 Jingjing An Yi Wu +1 位作者 Chenxi Gui Da Yan 《Building Simulation》 SCIE EI CSCD 2023年第8期1559-1582,共24页
Building energy modeling(BEM)has become increasingly used in building energy conservation research.Prototype building models are developed to represent the typical urban building characteristics of a specific building... Building energy modeling(BEM)has become increasingly used in building energy conservation research.Prototype building models are developed to represent the typical urban building characteristics of a specific building type,meteorological conditions,and construction year.This study included four residential buildings and 11 commercial buildings to represent nationwide building types in China.With consideration of five climate zones and different construction years corresponding to national standards,a total of 151 prototype building models were developed.The building envelope properties,occupancy and energy-related behaviors,and heating,ventilation,and air-conditioning(HVAC)system characteristics were defined according to the corresponding building energy efficiency design standards,HVAC design standards,and through other sources,such as questionnaire surveys,on-site measurements,and literature,which reflect the real situation of existing buildings in China.Based on the developed prototype buildings,a large database of 9225 models in 270 cities was further developed to facilitate users to simulate building energy in different cities.In conclusion,the developed prototype building models can represent realistic building characteristics and construction practices of the most common residential and commercial buildings in China,serving as an important foundation for BEM.The models can be used for analyses related to building energy conservation research on typical individual buildings,including energy-saving technologies,advanced controls,and new policies,and providing a reference for the development of building energy codes and standards. 展开更多
关键词 prototype building models building stock modeling Chinese building building performance simulation energy conservation
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A Stock Pricing Model Based on Arithmetic Brown Motion 被引量:1
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作者 YAN Yong-xin, HAN Wen-xiu School of Management, Tianjin University, Tianjin 300072, China 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2001年第3期339-342,共4页
This paper presents a new stock pricing model based on arithmetic Brown motion. The model overcomes the shortcomings of Gordon model completely. With the model investors can estimate the stock value of surplus compani... This paper presents a new stock pricing model based on arithmetic Brown motion. The model overcomes the shortcomings of Gordon model completely. With the model investors can estimate the stock value of surplus companies, deficit companies, zero increase companies and bankrupt companies in long term investment or in short term investment. 展开更多
关键词 stock pricing model arithmetic Brown motion Gordon model geometric Brown motion.
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