BACKGROUND TO THE INTRODUCTION OF HIGH YIELDING VARIETIES OF RICE IN THAILAND

This paper describes Thailand's experience to date with new technology in rice, namely new high yielding varieties with associated inputs, which forms one part of the "green revolution." First, the historical background in exports, production, and domestic marketing and pricing is presented. Next the significant developments in rice research in Thailand are described, followed by a brief outline of the adoption of new varieties. In the final section, some implications are drawn for future developments, based on the experience gained until now.Crop Production/Industries,

RICE IN THAILAND

Crop Production/Industries,

Brown bear attacks on humans : a worldwide perspective

The increasing trend of large carnivore attacks on humans not only raises human safety concerns but may also undermine large carnivore conservation efforts. Although rare, attacks by brown bears Ursus arctos are also on the rise and, although several studies have addressed this issue at local scales, information is lacking on a worldwide scale. Here, we investigated brown bear attacks (n = 664) on humans between 2000 and 2015 across most of the range inhabited by the species: North America (n = 183), Europe (n = 291), and East (n = 190). When the attacks occurred, half of the people were engaged in leisure activities and the main scenario was an encounter with a female with cubs. Attacks have increased significantly over time and were more frequent at high bear and low human population densities. There was no significant difference in the number of attacks between continents or between countries with different hunting practices. Understanding global patterns of bear attacks can help reduce dangerous encounters and, consequently, is crucial for informing wildlife managers and the public about appropriate measures to reduce this kind of conflicts in bear country.Peer reviewe

BACKGROUND TO THE INTRODUCTION OF HIGH YIELDING VARIETIES OF RICE IN THAILAND

This paper describes Thailand's experience to date with new technology in rice, namely new high yielding varieties with associated inputs, which forms one part of the "green revolution." First, the historical background in exports, production, and domestic marketing and pricing is presented. Next the significant developments in rice research in Thailand are described, followed by a brief outline of the adoption of new varieties. In the final section, some implications are drawn for future developments, based on the experience gained until now

Analysis of the Limited Resources Queuing System with Signals and Multiple Flows of Customers

In the paper, a wireless network is modelled in terms of multiserver queuing system with limited resources, random resource requirements and signals that trigger resource reallocation procedure. For the queuing system, we derive the set of balance equations and propose the solution method. Moreover, the formulas for main performance measures are obtained

Analysis of the Queuing Systems with Processor Sharing Service Discipline and Random Serving Rate Coefficients

In this paper, we develop the queuing system model with processor sharing discipline with random serving rate coefficients. Each arriving customer is characterized by its length (job volume) and a serving rate coefficient determined by some probability distributions. The coefficients remain constant during the service process of customers. The proposed model is aimed to model the service process of elastic sessions in wireless networks, in which each session is assigned to one of modulation and coding schemes (MCSs) according to the state of the radio channel. Each MCS is characterized by its value of the spectral efficiency, which is modeled by serving rate coefficients. First, we analyze the proposed model. Then we apply a simplification that significantly reduces the complexity of the analysis and allows us to deduce formulas for the blocking probability and the average sojourn time. Finally, we conduct a numerical analysis of the considered model

Response time analysis in terms of laplace-stieltjes transform for cloud computing system with hysteretic control and limited simultaneous activations

In the paper, cloud computing system with dynamic scaling is analyzed in terms of multiserver queuing system with hysteretic control of active server numbers based on queue length thresholds, and noninstantaneous server activation. To decrease computing complexity of the algorithms for evaluation of response time characteristics, we provide the analysis under simplifying assumption that only three servers may run activation procedures simultaneously Recurrent algorithm for Laplace-Stieltjes transform of the response time and the sojourn time is developed. The algorithm is used to analyze response time characteristics of a cloud computing system. Copyright © 2016 for the individual papers by the papers' authors

Approach to the analysis of probability measures of cloud computing systems with dynamic scaling

Cloud computing paradigm proved itself to be a good approach for efficient high-performance computational infrastructure design. Besides performance, one of the most important measures for cloud service providers is energy efficiency of the system. For better energy efficiency, in light load case additional virtual machines are switched off, and switched on again when load increases. Dynamic scaling increases performance of the system, but leads to increase in service costs. To avoid ping-pong effect in dynamic scaling, hysteresis approach is applied. Considering number of virtual machines in modern cloud platforms, special attention should be paid to efficiency of computing algorithm. In this work, we describe behavior of cloud computing system in terms of queuing system with threshold-based hysteretic control of active servers number and noninstantaneous server activation. We use state elimination technique to develop efficient algorithm for stationary probabilities calculations and estimation of its performance measures. © Springer International Publishing Switzerland 2016

Analysis of queueing system with resources and signals

We analyze a multi-server queueing system with limited resources and signals. A customer requires a random value (RV) of the shared resources. Each customer generates a flow of signals triggering the resource reallocation process that make a customer release the occupied amount of resources and request a new RV of resources instead. Considering users are constantly moving within the signal coverage area we describe a model of a wireless network where resources have to be reallocated due to changes in the requirements. We assume that user session cannot be interrupted because of lack of the resources in the instant of the resource reallocation. © Springer International Publishing AG 2017