scholarly journals A Risk-Based Interval Two-Stage Programming Model for Agricultural System Management under Uncertainty

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
Ye Xu ◽  
Guohe Huang
Keyword(s):  
Agricultural Production ◽  
Financial Risk ◽  
Production Management ◽  
Programming Model ◽  
Cost Effective ◽  
Critical Issue ◽  
Agricultural System ◽  
Two Stage ◽  
Production Pattern ◽  
System Benefit

Nonpoint source (NPS) pollution caused by agricultural activities is main reason that water quality in watershed becomes worse, even leading to deterioration. Moreover, pollution control is accompanied with revenue’s fall for agricultural system. How to design and generate a cost-effective and environmentally friendly agricultural production pattern is a critical issue for local managers. In this study, a risk-based interval two-stage programming model (RBITSP) was developed. Compared to general ITSP model, significant contribution made by RBITSP model was that it emphasized importance of financial risk under various probabilistic levels, rather than only being concentrated on expected economic benefit, where risk is expressed as the probability of not meeting target profit under each individual scenario realization. This way effectively avoided solutions’ inaccuracy caused by traditional expected objective function and generated a variety of solutions through adjusting weight coefficients, which reflected trade-off between system economy and reliability. A case study of agricultural production management with the Tai Lake watershed was used to demonstrate superiority of proposed model. Obtained results could be a base for designing land-structure adjustment patterns and farmland retirement schemes and realizing balance of system benefit, system-failure risk, and water-body protection.

scholarly journals A Strategic Agricultural Production Model with Risk and Return Considerations

1994 ◽  
Vol 23 (1) ◽  
pp. 37-46 ◽  
Author(s):  
Rhonda L. Aull-Hyde ◽  
Solomon Tadesse
Keyword(s):  
Strategic Planning ◽  
Agricultural Production ◽  
Financial Risk ◽  
Programming Model ◽  
Planning Horizon ◽  
Production Model ◽  
Risk And Return ◽  
Predetermined Level ◽  
Broiler Farm

Decision support systems are generally geared to short-term tactical decision making. As an alternative, this paper develops a mathematical programming model to evaluate long-term strategic alternatives in the context of farm-level agricultural production where a broiler farm considers long-term implications of diversification into commercial aquaculture. The model considers a ten-year strategic planning horizon, incorporates financial risk and return considerations, and accommodates capacity variations. Results indicate that a diversification strategy significantly increases farm profitability over a strategic planning horizon while simultaneously maintaining financial risk below a predetermined tolerance level and return on investment above a predetermined level.

Two-Stage Stochastic Programming Model for Robust Personal Rapid Transit Network Design

2017 ◽  
Vol 2650 (1) ◽  
pp. 152-162
Author(s):  
Kangjia Zhao ◽  
Jian Gang Jin ◽  
Der-Horng Lee
Keyword(s):  
Network Design ◽  
Travel Demand ◽  
Programming Model ◽  
Cost Effective ◽  
Network Design Problem ◽  
Rapid Transit ◽  
Two Stage ◽  
Personal Rapid Transit ◽  
On Demand ◽  
Mobility Method

This study investigated the personal rapid transit (PRT) guideway network design problem at a strategic level. PRT is known as an on-demand mobility method serving the first or last mile of travel demand, which can fluctuate significantly during a day. This on-demand property may make the system vulnerable to changes in the pattern of demand. The robustness of the PRT guideway network refers to the capability to fit different demand patterns. The motivation of this study was to take the uncertainty of demand into consideration in the process of network design to enhance the robustness of the PRT guideway network in operation. This problem was formulated as a two-stage stochastic linear programming model. The model was applied to a case study with real travel demand data from Singapore. The results of the comparison study show that the network designed via the proposed model is robust and cost-effective.

Two-stage chemical-biological treatment at Thessaloniki greater area WWTP - experiences and potentials

1995 ◽  
Vol 32 (9-10) ◽  
pp. 75-84 ◽  
Author(s):  
A. D. Andreadakis ◽  
G. H. Kristensen ◽  
A. Papadopoulos ◽  
C. Oikonomopoulos
Keyword(s):  
Biological Treatment ◽  
Treatment Plant ◽  
Cost Effective ◽  
Primary Treatment ◽  
Effective Control ◽  
Two Stage ◽  
Effluent Quality ◽  
Filamentous Microorganisms ◽  
Sludge Settling ◽  
The City

The wastewater from the city of Thessaloniki is discharged without treatment to the nearby inner part of the Thessaloniki Gulf. The existing, since 1989, treatment plant offers only primary treatment and did not operate since the expected effluent quality is not suitable for safe disposal to the available recipients. Upgrading of the plant for advanced biological treatment, including seasonal nitrogen removal, is due from 1995. In the mean time, after minor modifications completed in February 1992, the existing plant was put into operation as a two-stage chemical-biological treatment plant for 40 000 m3 d−1, which corresponds to about 35% of the total sewage flow. The operational results obtained during the two years operation period are presented and evaluated. All sewage and sludge treatment units of the plant perform better than expected, with the exception of the poor sludge settling characteristics, due to severe and persistent bulking caused by excessive growth of filamentous microorganisms, particularly M. Parvicella. Effective control of the bulking problem could lead to more cost-effective operation and increased influent flows.

scholarly journals A two-stage amplified PZT sensor for monitoring lung and heart sounds in discharged pneumonia patients

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Hongbin Chen ◽  
Shuai Yu ◽  
Haiyang Liu ◽  
Jie Liu ◽  
Yongguang Xiao ◽  
...  
Keyword(s):  
High Sensitivity ◽  
Cost Effective ◽  
High Ratio ◽  
Heart Sounds ◽  
Two Stage ◽  
Diagnosis And Prognosis ◽  
Sensor Device ◽  
Cost Effective Alternative ◽  
A Charge ◽  
Highly Sensitive Detection

AbstractAssessment of lung and heart states is of critical importance for patients with pneumonia. In this study, we present a small-sized and ultrasensitive accelerometer for continuous monitoring of lung and heart sounds to evaluate the lung and heart states of patients. Based on two-stage amplification, which consists of an asymmetric gapped cantilever and a charge amplifier, our accelerometer exhibited an extremely high ratio of sensitivity to noise compared with conventional structures. Our sensor achieves a high sensitivity of 9.2 V/g at frequencies less than 1000 Hz, making it suitable to use to monitor weak physiological signals, including heart and lung sounds. For the first time, lung injury, heart injury, and both lung and heart injuries in discharged pneumonia patients were revealed by our sensor device. Our sound sensor also successfully tracked the recovery course of the discharged pneumonia patients. Over time, the lung and heart states of the patients gradually improved after discharge. Our observations were in good agreement with clinical reports. Compared with conventional medical instruments, our sensor device provides rapid and highly sensitive detection of lung and heart sounds, which greatly helps in the evaluation of lung and heart states of pneumonia patients. This sensor provides a cost-effective alternative approach to the diagnosis and prognosis of pneumonia and has the potential for clinical and home-use health monitoring.

Development of a two-stage flexible fibre biofilm reactor for treatment of food processing wastewater

2003 ◽  
Vol 47 (11) ◽  
pp. 189-194 ◽  
Author(s):  
Q.J. Yu ◽  
H. Xu ◽  
D. Yao ◽  
P. Williams
Keyword(s):  
Removal Efficiency ◽  
Food Processing ◽  
Cost Effective ◽  
Biofilm Reactor ◽  
Cod Removal ◽  
Two Stage ◽  
Cod Removal Efficiency ◽  
Cost Effective Treatment ◽  
Removal Efficiencies ◽  
Food Processing Wastewater

Biofilm (or attached growth) reactors can be effectively used to treat organic wastewater from various industries such as food processing industry. They have a number of advantages including high organic loading rates (OLRs) and improved operational stability. A flexible fibre biofim reactor (FFBR) has been developed for efficient and cost effective treatment of food processing wastewater. In the process, simple flexible fibre packing with a very high specific surface area is used as support for microorganisms. The COD removal efficiencies for a range of OLRs have been studied. The FFBR can support an increasingly high OLR, but with a corresponding decrease in the COD removal efficiency. Therefore, a two-stage FFBR was developed to increase the treatment efficiency for systems with high OLRs. Experimental results indicated that a high overall COD removal efficiency could be achieved. At an influent COD of about 2700 mg/L and an OLR of 7.7 kgCOD/m3d, COD removal efficiencies of 76% and 82% were achieved in the first and the second stage of the reactor, respectively. The overall COD removal efficiency was 96%. Therefore, even for wastewater samples with high organic strength, high quality treated effluents could be readily achieved by the use of multiple stage FFBRs.

scholarly journals Trends and Policy Correlates of Agricultural Production and Agricultural Production Sustainability Outcomes in Ghana and Nigeria

2015 ◽  
Vol 8 (9) ◽  
pp. 71
Author(s):  
Olawale Emmanuel Olayide ◽  
Isaac Kow Tetteh ◽  
Labode Popoola
Keyword(s):  
Sustainable Development ◽  
International Development ◽  
Agricultural Production ◽  
Agricultural Development ◽  
Agricultural Sector ◽  
Agricultural System ◽  
Political Systems ◽  
Development Agenda ◽  
Development Outcomes ◽  
Development Agendas

This paper analysed policy correlates of agricultural production and agricultural production sustainability outcomes in Ghana and Nigeria. It underscores the influence of political systems and international development agendas as correlates of agricultural production and agricultural production sustainability outcomes. This is to the extent of providing evidence policy on agricultural production and agricultural production sustainability outcomes. Ghana and Nigeria have comparable farming/agricultural system and policy environment. Data used for the analyses spanned five decades. Trends analysis and inferential statistics were employed. The results revealed that policy correlates can contribute to the current discourse in sustainable development agenda and to resolving the dilemma of agricultural policy implementation for sustainable agricultural development, especially in Ghana and Nigeria. The findings reinforce the need for appropriate policies in transforming the agricultural sector while ensuring sustainable development outcomes.

Features of Water Function Zoning of the Surface Water in Sichuan Province

2015 ◽  
Vol 730 ◽  
pp. 221-229
Author(s):  
Rui Kun Cai ◽  
Fu Quan Ni ◽  
Yu Deng
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Water Resources ◽  
Agricultural Production ◽  
Production Management ◽  
Sichuan Province ◽  
Wastewater Discharge ◽  
Agricultural Wastewater ◽  
Key Points ◽  
Water Quality Deterioration

In this study, based on the water function zoning and the related analyses on the current situations and tendency of the pollutions on water environments in Sichuan province, concluded that the primary cause responsible for the deterioration of water resources is the discharge of agriculture wastewater, and the strengthening of agricultural production management as well as the reduction of the agricultural wastewater discharge are the key points to alleviate the water-quality deterioration.

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