IMPLICATIONS OF ALTERNATIVE POLICIES ON NITRATE CONTAMINATION OF GROUNDWATER

This study estimates the cost effectiveness of alternative environmental policies for controlling nitrate contamination of groundwater in the Seymour aquifer region of Texas. Results from biophysical simulation model are integrated with a farm-level optimization model. The study also compares the cost of bottled water, used as the lower-bound estimate of benefits of groundwater protection, with the least costly environmental policy. Results indicate that the least-cost policy alternative for the region is about $1 million either to farmers or to the local government and it is approximately three times the cost of bottled water.Environmental Economics and Policy,

High value products, supermarkets and vertical arrangements in Indonesia

" Indonesian economy has experienced some major changes during the last three decades and transformed from a predominantly agricultural economy to one that relies more heavily on its non-agricultural sector. Within agriculture, there has also been a change in the contribution of different sub sectors and high value products have grown relatively rapidly making agriculture more diversified. Similar to the changes in agricultural production, food consumption in Indonesia has shown a pattern of change over the past three decades, from a diet characterized primarily by the staple foods of cereals and cassava, to one that includes a larger share of fruits, fish, meats, dairy products and processed foods. Alongside the change in composition of food demand, newer forms of retail have also come up commonly known as supermarkets. However, the emergence of modern retailing has other consequences that go beyond consumers. It requires deep integration with farmers and can influence the production and transaction costs at farm level. It can also influence the distribution of value among different agents involved in production, intermediation, and retailing. In this paper we pursue three interrelated objectives. First, we review the structural changes that have taken place in Indonesian agriculture for the last three decades and the state of high value products. Second, we examine the driving forces behind the production of high value products and the constraints that limit their production. Third, we review the emergence of supermarkets and the vertical arrangements among farmers, traders/distributors, and supermarkets. We have relied both on primary and secondary data sources. Most of the secondary data has come from government directorates, different ministries and the central bureau of statistics (CBS) of the Government of Indonesia. In cases where secondary information was not readily available, we have also collected primary data. Our findings suggest that during the last three decades, there has been a significant structural change in Indonesian agriculture and the production of high value commodities and products –estate crops, livestock, fisheries, fruits and vegetables, and floriculture – has grown faster than the cereals. However, the extent of diversification towards high value products has remained limited to few regions and to few products within each sub sector. Factors that have contributed most in diversification are the rapid growth in income and accompanied changes in urban consumption in favor of high value products and agricultural mechanization. The economic crisis that was triggered by the currency crisis has had a long negative impact on agriculture sector. Structural changes in Indonesian agriculture have been accompanied by changes in consumption pattern in urban areas in favor of high value products and by a major change in retailing in the form of growth of modern supermarkets. To cater to the demand of changed urban consumption needs, supermarkets have been integrating with farmers through formal and informal contracts. This vertical relationship between farms and supermarkets that has been emerging in Indonesia has been helpful to follow grades and standards, to improve quality, and to reduce transaction costs and information asymmetries. It has also been helpful to reduce price and production risks at farm level and to ensure a higher price for farmers compared to traditional value chain. However, it seems that the participation of small holders in the vertical relationship depends largely on vendors. Within the vertical chain, supermarkets appropriate a monopsony rent. Important policies that can be drawn from this study are the greater emphasize on rural infrastructure, user right of state-owned estate to smallholders, promotion of public-private partnerships, encouragements of vertical arrangements, grades and standards, and bringing up the modern retailing sector under the purview of regulatory oversights." Authors' AbstractDiet ,High value agricultural products ,Supermarkets ,

The Rise of Supermarkets and Vertical Relationships in the Indonesian Food Value Chain: Causes and Consequences

This paper reviews the causes of the emergence of modern retailing and the vertical relationships in the Indonesian food value chain, and the consequences of these changes on market organization and value distribution. The findings of this paper suggest that there are both demand- and supply-side factors that contribute to the emergence of modern retailing. The evolution of vertical relationships between farmers and modern retailers observed in Indonesia is a direct response to risks and quality uncertainty. In the vertical relation, large-scale retailers may earn a monopsonistic rent, and there are risks of exclusion of small-scale farmers from the emerging food value chain. However, there are alternative channels through which farmers may sell their products, albeit at a lower price compared to the modern channels, and measures can be instituted to protect them against monopsonistic rents. The findings have important policy implications for developing countries.supermarkets, retailing, Indonesia, food value chain

Lambda hyperonic effect on the normal driplines

A generalized mass formula is used to calculate the neutron and proton drip lines of normal and lambda hypernuclei treating non-strange and strange nuclei on the same footing. Calculations suggest existence of several bound hypernuclei whose normal cores are unbound. Addition of Lambda or, Lambda-Lambda hyperon(s) to a normal nucleus is found to cause shifts of the neutron and proton driplines from their conventional limits.Comment: 6 pages, 4 tables, 0 figur

A new cellular automata model for city traffic

We present a new cellular automata model of vehicular traffic in cities by combining ideas borrowed from the Biham-Middleton-Levine (BML) model of city traffic and the Nagel-Schreckenberg (NaSch) model of highway traffic. The model exhibits a dynamical phase transition to a completely jammed phase at a critical density which depends on the time periods of the synchronized signals.Comment: 6 pages, 5 figures, uses Springer Macros 'lncse', to appear in "Traffic and Granular Flow '99: Social, Traffic, and Granular Dynamics" edited by D. Helbing, H. J. Herrmann, M. Schreckenberg, and D. E. Wolf (Springer, Berlin

Estimating Blood Pressure from Photoplethysmogram Signal and Demographic Features using Machine Learning Techniques

Hypertension is a potentially unsafe health ailment, which can be indicated directly from the Blood pressure (BP). Hypertension always leads to other health complications. Continuous monitoring of BP is very important; however, cuff-based BP measurements are discrete and uncomfortable to the user. To address this need, a cuff-less, continuous and a non-invasive BP measurement system is proposed using Photoplethysmogram (PPG) signal and demographic features using machine learning (ML) algorithms. PPG signals were acquired from 219 subjects, which undergo pre-processing and feature extraction steps. Time, frequency and time-frequency domain features were extracted from the PPG and their derivative signals. Feature selection techniques were used to reduce the computational complexity and to decrease the chance of over-fitting the ML algorithms. The features were then used to train and evaluate ML algorithms. The best regression models were selected for Systolic BP (SBP) and Diastolic BP (DBP) estimation individually. Gaussian Process Regression (GPR) along with ReliefF feature selection algorithm outperforms other algorithms in estimating SBP and DBP with a root-mean-square error (RMSE) of 6.74 and 3.59 respectively. This ML model can be implemented in hardware systems to continuously monitor BP and avoid any critical health conditions due to sudden changes.Comment: Accepted for publication in Sensor, 14 Figures, 14 Table

Microscopic energy flows in disordered Ising spin systems

An efficient microcanonical dynamics has been recently introduced for Ising spin models embedded in a generic connected graph even in the presence of disorder i.e. with the spin couplings chosen from a random distribution. Such a dynamics allows a coherent definition of local temperatures also when open boundaries are coupled to thermostats, imposing an energy flow. Within this framework, here we introduce a consistent definition for local energy currents and we study their dependence on the disorder. In the linear response regime, when the global gradient between thermostats is small, we also define local conductivities following a Fourier dicretized picture. Then, we work out a linearized "mean-field approximation", where local conductivities are supposed to depend on local couplings and temperatures only. We compare the approximated currents with the exact results of the nonlinear system, showing the reliability range of the mean-field approach, which proves very good at high temperatures and not so efficient in the critical region. In the numerical studies we focus on the disordered cylinder but our results could be extended to an arbitrary, disordered spin model on a generic discrete structures.Comment: 12 pages, 6 figure

ECONOMIC AND HYDROLOGIC IMPLICATIONS OF SUSPENDING IRRIGATION IN DRY YEARS

A dry year irrigation suspension has been proposed as a way of reallocating water when aquifer levels are low for the Texas Edwards Aquifer. Under this program, farmers would be paid to suspend irrigation to allow more spring flow or nonagricultural pumping. When irrigation is suspended in the east, springflow response is markedly larger than when suspended in the western portions of the aquifer. Most acreage participates when a $90 per acre payment is offered before the cropping season. Considerably higher payments are needed and less water saved for a suspension program instituted during the cropping season.Crop Production/Industries,