Second-generation biofuels : economics and policies

Recent increases in production of crop-based (or first-generation) biofuels have engendered increasing concerns over potential conflicts with food supplies and land protection, as well as disputes over greenhouse gas reductions. This has heightened a sense of urgency around the development of biofuels produced from non-food biomass (second-generation biofuels). This study reviews the economic potential and environmental implications of production of second-generation biofuels from a variety of various feedstocks. Although second-generation biofuels could significantly contribute to the future energy supply mix, cost is a major barrier to increasing commercial production in the near to medium term. Depending on various factors, the cost of second-generation (cellulosic) ethanol can be two to three times as high as the current price of gasoline on an energy equivalent basis. The cost of biodiesel produced from microalgae, a prospective feedstock, is many times higher than the current price of diesel. Policy instruments for increasing biofuels use, such as fiscal incentives, should be based on the relative merits of different types of biofuels.Energy Production and Transportation,Renewable Energy,Climate Change Mitigation and Green House Gases,Crops&Crop Management Systems,Transport Economics Policy&Planning

Compact Method for Modeling and Simulation of Memristor Devices: Ion Conductor Chalcogenide-Based Memristor Devices

A compact model and simulation methodology for chalcogenide based memristor devices is proposed. From a microprocessor design view point, it is important to be able to simulate large numbers of devices within the integrated circuit architecture in order to speed up reliably the development process. Ideally, device models would accurately describe the characteristic device behavior and would be represented by single-valued equations without requiring the need for recursive or numerically intensive solutions. With this in mind, we have developed an empirical chalcogenide compact memristor model that accurately describes all regions of operations of memristor devices employing single-valued equations

Silver Chalcogenide Based Memristor Devices

We have fabricated two-terminal chalcogenide-based devices containing Ge2Se3 and Ag that function as memristors. These devices have been electrically characterized at room temperature using quasi-static DC methods, AC sinusoidal methods, and AC pulse testing methods. In all cases, the devices exhibit memristive behavior

Development of a 1 kW Gravitational Water Vortex Hydropower Plant Prototype

A pilot testing of a Gravitational Water Vortex Hydropower Plant (GWVHP) has been done to evaluate the applicability in a real-world scenario and validate the results from the lab-scale model. A scaled-up model of a capacity of 1 kW was constructed for the evaluation purpose. The test provided data in good agreement with a lab-scale model and a proper visualization to install Gravitational Water Vortex in real-world scenarios. The project lasted for nearly four months and thus provided important information on the problems that might arise in scaling up the lab model to a micro-hydro system. The pilot testing shows an overall plant efficiency of 49%, validating the lab-based studies conducted beforehand. The information obtained from this pilot study shall be implemented in a micro-hydro project on a larger scale

A Review of Solar EnergyI Markets, Economics and Policies

Solar energy has experienced phenomenal growth in recent years due to both technological improvements resulting in cost reductions and government policies supportive of renewable energy development and utilization. This study analyzes the technical, economic and policy aspects of solar energy development and deployment. While the cost of solar energy has declined rapidly in the recent past, it still remains much higher than the cost of conventional energy technologies. Like other renewable energy technologies, solar energy benefits from fiscal and regulatory incentives and mandates, including tax credits and exemptions, feed-in-tariff, preferential interest rates, renewable portfolio standards and voluntary green power programs in many countries. Potential expansion of carbon credit markets also would provide additional incentives to solar energy deployment; however, the scale of incentives provided by the existing carbon market instruments, such as the Clean Development Mechanism of the Kyoto Protocol, is limited. Despite the huge technical potential, development and large-scale, market-driven deployment of solar energy technologies world-wide still has to overcome a number of technical and financial barriers. Unless these barriers are overcome, maintaining and increasing electricity supplies from solar energy will require continuation of potentially costly policy supports

Semi-supervised regression using diffusion on graphs

Indexación ScopusIn real-world machine learning applications, unlabeled training data are readily available, but labeled data are expensive and hard to obtain. Therefore, semi-supervised learning algorithms have gathered much attention. Previous studies in this area mainly focused on a semi-supervised classification problem, whereas semi-supervised regression has received less attention. In this paper, we proposed a novel semi-supervised regression algorithm using heat diffusion with a boundary-condition that guarantees a closed-form solution. Experiments from artificial and real datasets from business, biomedical, physical, and social domain show that the boundary-based heat diffusion method can effectively outperform the top state of the art methods. © 2021 The Author(s)https://www-sciencedirect-com.recursosbiblioteca.unab.cl/science/article/pii/S1568494621001113?via%3Dihu

Pathway to Care of Psychiatric Services in Gandaki Medical College Teaching Hospital in Western Nepal

Aims and Objectives: The sequence of contacts with individuals and organizations prompted by the distressed person's efforts, and those of his or her significant others, to seek help is known as the pathways to care. The study of the pathways to care provides the relevant information regarding the individual's health seeking and illness behaviour. A wide range of professionals including psychiatrists, psychologists, other doctors, faith-healers and religious healers cater to the needs of mentally ill patients. This study was carried out to identify the pathway to care of patients up to psychiatric care with no prior psychiatric treatment at GMCTH. Methodology: It is a cross-sectional, descriptive study conducted in GMCTH, Pokhara from Jan 2015 to Dec 2016. After ethical consideration, all new patients and those newly referred to the psychiatric services and agreed to participate were interviewed until the target 100 participants were recruited. ICD-10 was used for diagnosis. Data were computed and analyzed by using Microsoft excel and SPSS. Parametric & non parametric statistical technique was applied wherever appropriate. Results: Total of 100 patients (56 females, 44 males) was included in the study. Mean age of the entire study cohort was 37.17 years (SD 15.45). The mean no. of months to seek first help from a psychiatrist was 53.03 months (SD: 81.70). Conclusion: All the patients here eventually made treatment contact with psychiatrists. However, delay was pervasive. Delay in treatment has negative effect in the treatment outcome. The knowledge and recognition of psychological disorders by the traditional healers as well as other treatment providers in the community are crucial for early treatment of psychiatric patients