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I NTERNATIONAL J OURNAL OF E NERGY AND E NVIRONMENT Volume 3, Issue 3, 2012 pp.383-398 Journal homepage: www.IJEE.IEEFoundation.org ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2012 International Energy & Environment Foundation. All rights reserved. A greenhouse type solar dryer for small-scale dried food industries: Development and dissemination Serm Janjai Solar Energy Research Laboratory, Department of Physics, Faculty of Science, Silpakorn University, Nakhon Pathom 73000, Thailand. Abstract In this study, a greenhouse type solar dryer for small-scale dried food industries was developed and disseminated. The dryer consists of a parabolic roof structure covered with polycarbonate sheets on a concrete floor. The system is 8.0m in width, 20.0m in length and 3.5m in height, with a loading capacity about 1,000kg of fruits or vegetables. To ensure continuous drying operation, a 100kW-LPG gas burner was incorporated to supply hot air to the dryer during cloudy or rainy days. Nine 15-W DC fans powered by three 50-W PV modules were used to ventilate the dryer. This dryer was installed for a small-scale food industry at Nakhon Pathom in Thailand to produce osmotically dehydrated tomato. To investigate its performance, the dryer was used to dry 3 batches of osmotically dehydrated tomato. Results obtained from these experiments showed that drying air temperatures in the dryer varied from 35°C to 65°C. In addition, the drying time for these products was 2-3 days shorter than that of the natural sun drying and good quality dried products were obtained. A system of differential equations describing heat and moisture transfers during drying of osmotically dehydrated tomato was also developed. The simulated results agreed well with the experimental data. For dissemination purpose, other two units of this type of dryer were constructed and tested at two locations in Thailand and satisfactory results were obtained. Copyright © 2012 International Energy and Environment Foundation - All rights reserved. Keywords: Solar energy; Solar drying; Osmotically dehydrated tomato; Dried food industries; Greenhouse solar dryer. 1. Introduction Small-scale dried food industries are growing very fast in Southeast Asia, especially in Thailand. Situated in favorable climate conditions, Southeast Asian countries produce annually huge amounts of tropical fruits and vegetables. Drying is a major post-harvest processing of these food products. To respond to the demand of dried food from both domestic and international markets, a number of small- scaled dried food industries have been developed in Southeast Asia. In Thailand, some of these industries are established as community enterprises which are operated by villagers. To dry their products in commercial scale, most community enterprises use cabinet tray dryers heated by using liquefied petroleum gas (LPG) burners. In some cases, the drying starts with the open-sun drying and continues with a cabinet tray dryer using an LPG burner. In the last few years, the price of LPG has substantially increased, thus increasing the drying cost. As Thailand is located in the tropical zone which receives abundant solar radiation, the country has tremendous potentials for solar drying of fruits and vegetables [1, 2]. International Journal of Energy and Environment (IJEE), Volume 3, Issue 3, 2012, pp.383-398 ISSN 2076-2895 (Print), ISSN 2076-2909 (Online) ©2012 International Energy & Development and Organogenesis Development and Organogenesis Bởi: OpenStaxCollege The process by which an organism develops from a single-celled zygote to a multicellular organism is complex and well regulated The regulation occurs through signaling between cells and tissues and responses in the form of differential gene expression Early Embryonic Development Fertilization is the process in which gametes (an egg and sperm) fuse to form a zygote ([link]) To ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg In mammals, a layer called the zona pellucida protects the egg At the tip of the head of a sperm cell is a structure like a lysosome called the acrosome, which contains enzymes When a sperm binds to the zona pellucida, a series of events, called the acrosomal reactions, take place These reactions, involving enzymes from the acrosome, allow the sperm plasma membrane to fuse with the egg plasma membrane and permit the sperm nucleus to transfer into the ovum The nuclear membranes of the egg and sperm break down and the two haploid nuclei fuse to form a diploid nucleus or genome Fertilization is the process in which sperm and egg fuse to form a zygote (credit: scale-bar data from Matt Russell) 1/4 Development and Organogenesis To ensure that no more than one sperm fertilizes the egg, once the acrosomal reactions take place at one location of the egg membrane, the egg releases proteins in other locations to prevent other sperm from fusing with the egg The development of multi-cellular organisms begins from this single-celled zygote, which undergoes rapid cell division, called cleavage ([link]a), to form a hollow ball of cells called a blastula ([link]b) (a) During cleavage, the zygote rapidly divides into multiple cells (b) The cells rearrange themselves to form a hollow ball called the blastula (credit a: modification of work by Gray's Anatomy; credit b: modification of work by Pearson Scott Foresman; donated to the Wikimedia Foundation) In mammals, the blastula forms the blastocyst in the next stage of development Here the cells in the blastula arrange themselves in two layers: the inner cell mass, and an outer layer called the trophoblast The inner cell mass will go on to form the embryo The trophoblast secretes enzymes that allow implantation of the blastocyst into the endometrium of the uterus The trophoblast will contribute to the placenta and nourish the embryo Concept in Action Visit the Virtual Human Embryo project at the Endowment for Human Development site to click through an interactive of the stages of embryo development, including micrographs and rotating 3-D images 2/4 Development and Organogenesis The cells in the blastula then rearrange themselves spatially to form three layers of cells This process is called gastrulation During gastrulation, the blastula folds in on itself and cells migrate to form the three layers of cells ([link]) in a structure, the gastrula, with a hollow space that will become the digestive tract Each of the layers of cells is called a germ layer and will differentiate into different organ systems Gastrulation is the process wherein the cells in the blastula rearrange themselves to form the germ layers (credit: modification of work by Abigail Pyne) The three germ layers are the endoderm, the ectoderm, and the mesoderm Cells in each germ layer differentiate into tissues and embryonic organs The ectoderm gives rise to the nervous system and the epidermis, among other tissues The mesoderm gives rise to the muscle cells and connective tissue in the body The endoderm gives rise to the gut and many internal organs Organogenesis Gastrulation leads to the formation of the three germ layers that give rise during further development to the different organs in the animal body This process is called organogenesis Organs develop from the germ layers through the process of differentiation During differentiation, the embryonic stem cells express specific sets of genes that will determine their ultimate cell type For example, some cells in the ectoderm will express the genes specific to skin cells As a result, these cells will take on the shape and characteristics of epidermal cells The process of differentiation is regulated by locationspecific chemical signals from the cell’s embryonic environment that sets in play a cascade of events that regulates gene expression Section Summary The early stages of embryonic development begin with fertilization The process of fertilization is tightly controlled to ensure that only one sperm fuses with one egg After fertilization, the zygote undergoes cleavage to form the blastula The blastula, which in some species is a hollow ball of cells, undergoes a process called gastrulation, during which the three germ layers form The ectoderm gives rise to the nervous system and 3/4 Development and Organogenesis the epidermal skin cells, the mesoderm gives rise to the muscle cells and connective ... SUSTAINABLE DEVELOPMENT AND THE FUTURE After studying this chapter, you should be able to: 1. Explain why the balance of nature was altered only recently 2. Relate how humans were able to control nature 3. Enumerate the consequences of controlling nature 4. Comprehend the pressure on the environment, resulting from rapid increase population 5. Understand the problem of uneven distribution of wealth 6. Distinguish the problem of solutions offered to problem impacts in the world. 5.1. THE GLOBAL ENVIRONMENTAL SITUATION Scientists have estimated that the Earth is more than four billion years old, and it will continue to exist for around the same period of time. Life on Earth as we know it today came into being around three billion years ago. Based on fossils found around the world, human beings have inhabited the Earth for more than two million years. All this time, nature and life on Earth lived in equilibrium. There was no major disturbance which could alter the balance of nature. This was true up to around 2000 years ago. At around that time, people began to disturb the environment in such a manner as to effect the global environment. The rampant and reckless cuttings of trees in virgin forests have resulted in soil erosion, flooding, expansion of deserts, and destruction of lakes. Overexploitation of other natural resources, like fish and other aquatic resources, has resulted in alarming decrease of catch worldwide. Too much use of fossil fuels, like oil and other minerals, has depleted these natural resources to much an extent that the supply may not last for another one hundred years. It takes millions of years to form oil from the fossils of plants. The industrial revolution has produced all kinds of hazardous materials that harmed the environment- pollution of the air, water, land, and the atmosphere. Many of these hazardous substances are also toxic to humans as well as to other animals. To be fair to those concerned, all these were the unwanted effects of a desire to improve the quality of life - a very noble intention. In fact, as direct consequences of scientific breakthroughs in many fields of human endeavor, people have in many ways succeeded in this worthy ambition. People were, to a certain extent, able to control nature. By applying what they have discovered about the laws of nature, they were able to conquer darkness though electric bulbs and fluorescent lamps, hot weather conditions through electric fans and air conditioners, and cold weather through heaters. Through modern medicines and sanitation, they were able to control the spread of diseases; through modern agriculture, they were able to produce more food containing better nutrients. The overall result of better living conditions, better sanitation, and better nutrition includes rise in life expectancy and low infant mortality. The net effect is rapid increase in population. Insightfulness The luxurious life-style of the rich and famous contributes to environmental degradation. According to the United Nations Statistical Yearbook (1988), the doubling of the population between 1950 and 1986 was accompanied by grain consumption of 2.6 times, energy use of 3.7 fold, and quadruple economic output and sevenfold increase in the production of manufactured goods. All these were accompanied by more than ninefold increase in water, air, and land pollution. Insightfulness Most developed countries have zero or very, very low population growth rate. But the irony is, situation differ from region to region and country to country. Because of the wide gap Test-Driven Development and Impostors T he previous chapter looked at the tools supporting TDD, but said little about TDD itself. This chapter will use several lengthy examples to show how tests are written, and along the way, you’ll get to see how refactorings are performed. We’ll also take a quick look at IDE refactoring support. A consistent theme is code isolation through impostors. Impostors, or test doubles, are among the most powerful unit-testing techniques available. There is a strong temptation to overuse them, but this can result in overspecified tests. Impostors are painful to produce by hand, but there are several packages that minimize this pain. Most fall into one of two categories based on how expectations are specified. One uses a domain-specific language, and the other uses a record-replay model. I examine a repre- sentative from each camp: pMock and PyMock. We’ll examine these packages in detail in the second half of the chapter, which presents two substantial examples. The same code will be implemented with pMock in the first exam- ple and with PyMock in the second example. Along the way, I’ll discuss a few tests and demonstrate a few refactorings. 1 Each package imbues the resulting code with a distinct character, and we’ll explore these effects. Moving Beyond Acceptance Tests Currently, all the logic for the reader application resides within the main() method. That’s OK, though, because it’s all a sham anyway. Iterative design methods focus on taking whatever functional or semifunctional code you have and fleshing it out a little more. The process con- tinues until at some point the code no longer perpetrates a sham, and it stands on its own. The main() method is a hook between Setuptools and our application class. Currently, there is no application class, so what little exists is contained in this method. The next steps create the application class and move the logic from main(). Where do the new tests go? If they’re application tests, then they should go into test_application.py. However, this file already contains a number of acceptance tests. 175 CHAPTER 7 1. Here, I’m using the word few in a strictly mathematical sense. That is to say that it’s smaller than the set of integers. Since there can be only zero, one, or many items, it follows that many is larger than the integers. Therefore, few is smaller than many (for all the good that does anyone). 9810ch07.qxd 6/3/08 2:08 PM Page 175 The two should be separate, so the existing file should be copied to acceptance_tests.py. From Eclipse, this is done by selecting test_application.py in an explorer view, and then choosing Team ➤ Copy To from the context menu. From the command line, it is copied with svn copy. The application tests are implemented as native Nose tests. Nose tests are functions within a module (a.k.a. a .py file). The test modules import assertions from the package nose.tools: from nose.tools import * '''Test the application class RSReader''' The new application class is named rsreader.application.RSReader. You move the func- tionality from rsreader.application.main into rsreader.application.RSReader.main. At this point, you don’t need to create any tests, since the code is a direct product of refactoring. The file test_application.py becomes nothing more than a holder for your unwritten tests. This class RSReader has the single method main(). The application’s main() function creates an instance of RSReader and then delegates it to the instance’s main(argv) method: def main(): RSReader().main(sys.argv) class RSReader(object): xkcd_items = \ """Wed, 05 Dec 2007 05:00:00 -0000: xkcd.com: Python Mon, 03 Dec 2007 05:00:00 -0000: xkcd.com: Far Away""" def main(self, argv): if argv[1:]: print self.xkcd_items The program outputs one line for each RSS item. The line Modern Macroeconomics In loving memory of Brian’s parents, Joseph and Margaret Snowdon, and Howard’s father, Philip M. Vane Modern Macroeconomics Its Origins, Development and Current State Brian Snowdon Principal Lecturer in Economics in the Newcastle Business School, Northumbria University, Newcastle upon Tyne, UK Howard R. Vane Professor of Economics in the School of Accounting, Finance and Economics, Liverpool John Moores University, Liverpool, UK Edward Elgar Cheltenham, UK • Northampton, MA, USA © Brian Snowdon, Howard R. Vane 2005 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical or photocopying, recording, or otherwise without the prior permission of the publisher. Published by Edward Elgar Publishing Limited Glensanda House Montpellier Parade Cheltenham Glos GL50 1UA UK Edward Elgar Publishing, Inc. 136 West Street Suite 202 Northampton Massachusetts 01060 USA A catalogue record for this book is available from the British Library ISBN 1 84376 394 X (cased) 1 84542 208 2 (paperback) Typeset by Manton Typesetters, Louth, Lincolnshire, UK. Printed and bound in Great Britain by MPG Books Ltd, Bodmin, Cornwall. v Contents List of figures x List of tables xiii Preface xiv Acknowledgements xvii 1 Understanding modern macroeconomics 1 1.1 Macroeconomic issues and ideas 1 1.2 The role of economic theory and controversy 3 1.3 Objectives, instruments and the role of government 7 1.4 The Great Depression 9 1.5 Keynes and the birth of macroeconomics 13 1.6 The rise and fall of the Keynesian consensus 15 1.7 Theoretical schizophrenia and the neoclassical synthesis 21 1.8 Schools of thought in macroeconomics after Keynes 24 1.9 The new political macroeconomics 29 1.10 The renaissance of economic growth research 32 2Keynes v. the ‘old’ classical model 36 2.1 Introduction 36 2.2 Classical macroeconomics 37 2.3 Employment and output determination 38 2.4 Say’s Law 45 2.5 The quantity theory of money 50 2.6 Keynes’s General Theory 54 2.7 Interpreting the General Theory 57 2.8 Keynes’s main propositions 58 2.9 Keynes’s analysis of the labour market 65 2.10 Keynes’s rejection of Say’s Law 69 2.11 Keynes and the quantity theory of money 69 2.12 Three important interpretations of Keynes 70 2.13 The ‘new’ Keynes scholarship 75 2.14 Causes and consequences of the Great Depression 76 2.15 How to pay for the war 82 2.16 Keynes and international macroeconomics 83 2.17 Keynes’s legacy and the classical revival 85 Interview with Robert Skidelsky 91 3 The orthodox Keynesian school 101 3.1 Introduction 101 3.2 The orthodox Keynesian school 102 3.3 The IS–LM model for a closed economy 102 3.4 Underemployment equilibrium in the Keynesian model 114 3.5 The IS–LM model for an open economy 123 3.6 The Phillips curve and orthodox Keynesian economics 135 3.7 The central propositions of orthodox Keynesian economics 144 Interview with James Tobin 148 4 The orthodox monetarist school 163 4.1 Introduction 163 4.2 The quantity theory of money approach 165 4.3 The expectations-augmented Phillips curve analysis 174 4.4 The monetary approach to balance of payments theory and exchange rate determination 187 4.5 The orthodox monetarist school and stabilization policy 192 Interview with Milton Friedman 198 5 The new classical school 219 5.1 Introduction 219 5.2 The influence of Robert E. Lucas Jr 220 5.3 The structure of new classical models 223 5.4 Equilibrium business cycle theory 236 5.5 The policy implications of the new classical approach 242 5.6 An assessment 267 Interview with Robert E. Lucas Jr 272 6 The real business cycle school 294 6.1 Introduction: the demise of new classical macroeconomics mark I 294 6.2 The transition from monetary to real equilibrium enter for Real EMIT C state Week 4: Firm Site Selection and Industrial land Use. • Households as a factor of production versus as a client. • Historic cities – commerce and industry at the Center. • Changes in Technology and Transportation. • Modern Industrial location. enter for Real EMIT C state Firm – Household Linkages • Firms sell products to workers - the friction is “shopping” or client visit transportation costs: Retail stores, “retail” services [insurance dealers, barber shops, retail brokerage offices…] • Firms sell products nationally and employ workers as a factor of production – the friction is the commuting of workers enter for Real EMIT C state Sources of Spatial data on Firms and employment • Firms (IRS, SEC) versus Establishments (BLS, Census). SIC codes • Federal Establishment files (8 million) • State surveys (monthly, quarterly, annual) • Recent release of detailed data by Zip code – “a revolution” [http://www.census.gov/epcd/www/zipstats.html.] enter for Real EMIT C state Employment dispersal in Dallas CMSA ( see: Shukla and Waddell, RSUE, 1991) enter for Real EMIT C state Employment decentralization in Boston Boston, City Boston, Suburbs Employment Category 1970 1980 1990 2000 1970 1980 1990 2000 i i lt , 539,720 1,046,936 1, 1, ,350Pr vate Non-Agr cu ural 496,548 492 095 613,385 1,334,948 648,863 888 Mining 180 129 267 (D) 682 1,187 1,513 (D) Construction 23,159 12,589 14,967 20,803 64,156 59,336 87,537 112,173 Manufacturing 68,078 55,830 34,603 30,071 316,318 367,345 303,883 247,888 Transportation and public utilities 45,458 39,890 38,187 40,911 45,581 55,618 64,333 75,222 Wholesale trade 45,170 31,622 21,706 19,106 56,164 83,974 111,097 116,793 Retail trade 87,315 65,420 67,507 72,227 214,694 263,779 312,328 331,863 Finance, insurance, and real estate 76,743 76,991 94,534 108,413 60,812 97,491 130,903 157,846 Services 150,445 209,624 267,949 321,854 288,529 406,218 637,269 845,450 enter for Real EMIT C state Monocentric City: Central Business District r f (d) r (d) Firms (CBD) r Land Rent Residents a m b Distance (d) enter for Real EMIT C state 1). Profit/unit output (π) π = [S –AC –sd] -r f (d)/Q S = sale price/unit AC = average cost (inc. capital) s = shipping cost to port d = distance to port r f (d)= firm rent per acre Q = units of output per acre In equilibrium profits must be fixed across locations. enter for Real EMIT C state 2). Equal profit rent function. r f (d) = [S – AC – sd - π]*Q 3). Slope of firm rent function: ∂r f / ∂d= -s*Q 4). Historic changes in s, Q. - From carts to water to rail to truck - from 6 story lofts to single story Sheds 5). A “Flat” Industrial Rent Gradient? [Lockwood and Rutherford] enter for Real EMIT C state With a “flat” rent gradient: Industries move to the edge Land Rent CBD Residents Industries Services r a m1 m2 b distance (d) MIT Center for Real Estate Modern Industrial Location Why do industries locate: - Next to Highways - Next to Airports or seaports - On land that is recycled, wet, or marginal But also: - In areas already developed. - Near to population ? [Shukla-Waddell, Struyk-James] [...]...MIT Center for Real Estate If residential rents look like this – then where do industrial properties locate? Land Rent Negativ e Value of Proximity Positive Value of Access Distance from Highway ... rise to the nervous system and 3/4 Development and Organogenesis the epidermal skin cells, the mesoderm gives rise to the muscle cells and connective tissue in the body, and the endoderm gives rise... an interactive of the stages of embryo development, including micrographs and rotating 3-D images 2/4 Development and Organogenesis The cells in the blastula then rearrange themselves spatially.. .Development and Organogenesis To ensure that no more than one sperm fertilizes the egg, once the acrosomal