Four years have passed since the publication of Christopher Alexander's Notes on the Synthesi... more Four years have passed since the publication of Christopher Alexander's Notes on the Synthesis of Form. And already the book has gone through two printings and been translated into Italian and Japanese. In its most basic form, it presents a method for aiding the designer in systematically structuring physical design problems. Interestingly enough, it has been criticized both by what might be called the “traditional right” and the “new left” of architectural education. The former accuses the method of being partial in that it addresses itself primarily to the functional side of the problem and neglects the esthetic and culturally symbolic aspects of architectural solutions—an aspect to which the traditional right gives primary emphasis. From the other side, the “new left” attacks the method as systematically unreliable since it does not contain the rigor of scientific method. In fact, it is said that Alexander's method cannot deal objectively with the “true” complexity of design problems. Subjective judgme...
SOLAR5 is a simple, easy-to-use graphic design tool that gives architects an instantaneous displa... more SOLAR5 is a simple, easy-to-use graphic design tool that gives architects an instantaneous display of their building's energy performance and allows immediate on-line design revisions. It is intended for use at the very beginning of the design process, the time when most of the decisions affecting the building's energy performance must be made, but when the building is the most vaguely defined.
To increase the application of nocturnal ventilative cooling (night flushing) and daytime comfort... more To increase the application of nocturnal ventilative cooling (night flushing) and daytime comfort ventilation an intelligent control system has been designed that manages air flow according to cooling needs in a building and resources in the environment. This system is a microcomputer-controlled thermostat with both indoor and outdoor temperature sensors that can control a whole-house fan, in addition to the furnace and air conditioner. No such thermostat is currently available commercially. The rules for various control strategies have been programmed and tested using two slab floor test cells. It has proven effective in reducing both the maximum temperature and the number of overheated hours in the test cell, compared to the control cell. An “optimum ” series was tested experimentally and modeled with the HEED computer program in different California climate zones demonstrating potential savings for ratepayers.
A microcomputer-controlled thermostat has been designed that manages airflow according to cooling... more A microcomputer-controlled thermostat has been designed that manages airflow according to cooling needs in a building and resources in the environment. This system is an intelligent control system with both indoor and outdoor temperature sensors that uses rules to control a whole-house fan, in addition to the furnace and air conditioner. No such thermostat is currently available commercially. The most effective rule, proposed in a previous paper, was used to determine the effects of modifying the window area and the amount of mass. Results demonstrate the importance of adding mass and controlling solar radiation on a venting system that uses outdoor air-economizer cooling-. 1.
In the future of Computer Aided Architectural Design (CAAD), architects clearly need more then ju... more In the future of Computer Aided Architectural Design (CAAD), architects clearly need more then just computer aided design and drafting systems (CAD). Unquestionably CAD systems continue to become increasingly powerful, but there is more to designing a good building than its three-dimensional existence, especially in the eyes of all the non-architects of the world: users, owners, contractors, regulators, environmentalists.... The ultimate measure of a building's quality has something to do with how well it behaves over time. Predictions about its performance have many different dimensions; how much it costs to build, to operate, and to demolish; how comfortable it is; how effectively people can perform their functions in it; how much energy it uses or wastes. Every year dozens of building performance simulation programs are being written that can predict performance over time along any of these dimensions. That is why the need for both CAD systems and performance predictors can ...
A prototype microcomputer-controlled thermostat that can operate different systems in a building ... more A prototype microcomputer-controlled thermostat that can operate different systems in a building according to comfort requirements and resources in the environment has been developed by the authors. This intelligent control system has been tested measuring indoor and outdoor temperature to operate a fan and/or blinds. This paper presents some results of a study done in the summer of 2004, comparing the performance of the test cell operating with both the fan and shades with previous series in the summers of 2002 and 2003 with only either the fan or the shade operating. All of them were also compared to a reference cell without shades or fans. Other variables, such as the amount of mass and insulation levels are fixed in all series. Results indicate that in this climate all of these strategies help to achieve more comfortable conditions inside the experimental cell than the control cell but that some perform better than others. A higher air change works better than a lower air change...
In California there are 16 different climate zones as defined in the California Energy code (Titl... more In California there are 16 different climate zones as defined in the California Energy code (Title 24). The code requires slightly different types of buildings in each zone. These different building code requirements make it important for architects, builders, contractors, and homeowners to understand the resources of their unique local climate and how it will influence the performance of their buildings. The objective of this project is to create a tool called Climate Consultant 4.0 that adds a number of features to those in the prior version 3.0, including new graphic screens such as a Monthly Diurnal Averages plot. It also calculates a set of the Top 20 Design Guidelines based on your unique climate, and displays a sketch illustrating how each applies. A new dynamic graphic tutorial has been created to explain the Psychrometric Chart, and how the relationship between air temperature and humidity influences human thermal comfort and HVAC systems design. Climate Consultant 4.0 help...
The use of windows as passive solar collectors is discussed, and SOLAR-2, an interactive computer... more The use of windows as passive solar collectors is discussed, and SOLAR-2, an interactive computer-aided design program for designing an energy efficient window-sunshade assembly, is described. Windows with properly designed shading and orientation will supply a significant portion of a building's heating needs during the winter months and also exclude radiation and reduce cooling loads during summer months. The designing of a building's passive solar collector windows will be facilitated by the SOLAR-2 computer program which can deal with the computational complexity of evaluating each window's geometry, orientation, transmitting materials, shading devices, and construction details.
HEED (Home Energy Efficient Design) shows architects, builders, and homeowners how to design or r... more HEED (Home Energy Efficient Design) shows architects, builders, and homeowners how to design or remodel their buildings to reduce or even eliminate air conditioning loads. It is intended for use at the very beginning of the design process, when most of the critical decisions effecting energy consumption are made. This paper goes step-by-step through a typical building remodeling design using HEED. It shows graphically the differences in performance between various passive cooling alternatives including things like window shading, thermal mass, ventilation, improved envelope, and optimized shape and orientation, etc. Among the features users especially appreciate is the simple way they can draw in floor plans and how they can drag and drop windows onto each facade. HEED shows them bar charts comparing the difference in heating and cooling energy costs for up to nine different designs. The objective is to facilitate a simple, non-technical, smooth flowing, decision-making experience. ...
Phrases like solar heating, passive cooling, or energy-conserving design should be eliminated as ... more Phrases like solar heating, passive cooling, or energy-conserving design should be eliminated as quickly as possible from the vocabularies of all practicing architects. Such phrases should be replaced by the phrase ''competent design'' and simply taken for granted. Every client has a right to expect these features from a qualified professional just as they expect a structurally sound, fire-safe, and weather-tight building. In times past, indigenous builders knew very well how to design thermally efficient and energy-conserving buildings. They may not have understood the theory behind their designs, but the rituals, traditions, and cultural taboos governing their work embodied wisdom gained over the centuries. The elegance and thermal ingenuity of these buildings are still admired by even the most high-tech, post-modern architects of today.
Every design decision an architect makes carries with it a hidden environmental cost. Architects ... more Every design decision an architect makes carries with it a hidden environmental cost. Architects are concerned about issues like sustainability, greenhouse gas production, and other environmental costs, but there is little they can do until there is an easy way to visualize exactly what these costs look like. This paper describes a user-friendly microcomputer design tool that calculates the environmental costs of each architectural design decision, and then displays an easy-tounderstand picture of how these costs change from one design to the next. This new version of SOLAR-5 shows how a well designed passive building produces less air pollution and greenhouse gasses, and thus how it contributes to a more sustainable environment. Seven different atmospheric pollutants are included in the database, measured in pounds of pollution per KwHr for electric power generated and per MMBTU of natural gas or heating oil burned. SOLAR-5 also displays the amount of energy a building uses and its...
Energy efficient design requires different types of buildings in each different climate. This mak... more Energy efficient design requires different types of buildings in each different climate. This makes it essential for architects, builders, contractors, and homeowners to understand the resources of their unique local climate and how it influences the performance of their buildings. Climate Consultant 4.0 has been created to achieve this. It adds a number of new features, including new graphic screens and an interactive tutorial to explain the psychrometric chart. It also automatically creates a list of Design Guidelines based on the attributes of each unique climate and it then displays a sketch illustrating how each Guideline applies. Thus, Climate Consultant 4.0 helps people who are designing, constructing, and maintaining buildings anywhere in the world understand the resources of their local climate and how it impacts their building’s performance.
The new Oak Park Library Project has many kinds of clients, each of whom will in some way influen... more The new Oak Park Library Project has many kinds of clients, each of whom will in some way influence the final building design. A surprising number of these stake-holders represent different issues of sustainability including energy efficiency, and air pollution. This paper shows how a microcomputer design tool, SOLAR-5.4, is used during the Schematic Design Phase to simulate and display the performance of each different design scheme, in terms meaningful to each of the different groups of clients. SOLAR-5.4 is extremely fast and user-friendly. It is intended for use by architects at the very beginning of the design process when most of the basic decisions are made that later on turn out to have the greatest impacts on the building`s long term performance. The objective is to help the architect make the best possible decisions while the design is still in its formative stage.
A major interior landscaping project is a central component of a proposed corporate headquarters.... more A major interior landscaping project is a central component of a proposed corporate headquarters. While interior landscaping is a significant part of many such projects, typical plant losses of 20-40 percent each year are not acceptable for this installation. The client is confident of their ability to control important factors to sustain plant growth such as soil, irrigation, and plant compatibility. Daylighting for plants remains as the element most difficult to predict and control in an integrated manner in the interior environment. The architect proposed two different skylight designs. The study provides a methodology based on physical model testing and computer simulation using California Energy Commission (CEC) climate data that resulted in the required illumination level data for the architect during the early phases of project development.
In California there are 16 different climate zones, as defined in the California Energy Code (Tit... more In California there are 16 different climate zones, as defined in the California Energy Code (Title24). The code requires slightly different types of buildings in each zone. These different building code requirements make it important for people who are designing, building, or maintaining these buildings to understand the unique attributes of their climate and how it will influence the design and performance of their buildings. In this UCEI project we developed a simple, free, easy-to-use, graphic-based computer program called Climate Consultant 3, and we have posted it on the State of California’s Flex Your Power web site and on the UCLA Energy Design Tools web site. Our objective is to make it freely accessible to architects, builders, contractors, and homeowners, etc., to help them understand their local climate and how it impacts their building’s energy consumption.
In order to compare the performance of three different cooling strategies (External Operable Shad... more In order to compare the performance of three different cooling strategies (External Operable Shades, Internal Operable Shades, or a Whole-House Fan) in all 16 California climate zones, hourly performance data was recorded in a pair of full height test cells. The results were used to validate HEED (Home Energy Efficient Design), a whole-building energy simulation program. HEED automatically designed two 2000 sq.ft. houses, one to Meets the Energy Code, (Californias Title24), and the other that was a More Energy Efficient scheme. The Code requires a slightly different buildings in each of Californias 16 climate zones. On a state-wide basis these More Energy Efficient homes designed by HEED use about 35 % less energy than the homes that Meet the Energy Code (Title 24). One of the three cooling strategies was added to each of the two basecase homes in each climate In the Title 24 home the Whole-House fan is only half as good as either of the two Operable Shades. However in the More Ener...
The Psychrometric Chart tutorial is a downloadable animated tutorial application which explains t... more The Psychrometric Chart tutorial is a downloadable animated tutorial application which explains the various features of the Psychrometric Chart and how it illustrates indoor or outdoor air conditions and their relation to human thermal comfort. This tutorial is written in Flash and various audio-visual techniques are incorporated to create an effective educational resource. This paper outlines the underpinning developmental theories for the tutorial program and subsequently describes, in detail, each of the features it presents: dry bulb temperature, absolute humidity, saturation line, relative humidity, wet bulb temperature, dew point temperature, precipitation, hourly data, comfort zones, and mechanical systems. It is concluded with user feedback and indications of future enhancements.
ABSTRACT A prototype microcomputer-controlled thermostat was developed that can manage airflow ac... more ABSTRACT A prototype microcomputer-controlled thermostat was developed that can manage airflow according to cooling the needs in a building and the resources in the environment. This intelligent control system measures both indoor and outdoor temperature and uses decision rules to control a whole-house fan, in addition to the furnace and air condi-tioner. No such residential thermostat is currently commercially available. This paper presents the controller strategy that optimizes cooling with outdoor air. This paper also quantifies the effects of modifying the amount of thermal mass and the window area on indoor comfort when using this controller. These test confirm that smaller windows and more mass performed better than larger windows and less mass, and that higher volumes of controlled ventilation outper-formed fixed ventilation rates.
Four years have passed since the publication of Christopher Alexander's Notes on the Synthesi... more Four years have passed since the publication of Christopher Alexander's Notes on the Synthesis of Form. And already the book has gone through two printings and been translated into Italian and Japanese. In its most basic form, it presents a method for aiding the designer in systematically structuring physical design problems. Interestingly enough, it has been criticized both by what might be called the “traditional right” and the “new left” of architectural education. The former accuses the method of being partial in that it addresses itself primarily to the functional side of the problem and neglects the esthetic and culturally symbolic aspects of architectural solutions—an aspect to which the traditional right gives primary emphasis. From the other side, the “new left” attacks the method as systematically unreliable since it does not contain the rigor of scientific method. In fact, it is said that Alexander's method cannot deal objectively with the “true” complexity of design problems. Subjective judgme...
SOLAR5 is a simple, easy-to-use graphic design tool that gives architects an instantaneous displa... more SOLAR5 is a simple, easy-to-use graphic design tool that gives architects an instantaneous display of their building's energy performance and allows immediate on-line design revisions. It is intended for use at the very beginning of the design process, the time when most of the decisions affecting the building's energy performance must be made, but when the building is the most vaguely defined.
To increase the application of nocturnal ventilative cooling (night flushing) and daytime comfort... more To increase the application of nocturnal ventilative cooling (night flushing) and daytime comfort ventilation an intelligent control system has been designed that manages air flow according to cooling needs in a building and resources in the environment. This system is a microcomputer-controlled thermostat with both indoor and outdoor temperature sensors that can control a whole-house fan, in addition to the furnace and air conditioner. No such thermostat is currently available commercially. The rules for various control strategies have been programmed and tested using two slab floor test cells. It has proven effective in reducing both the maximum temperature and the number of overheated hours in the test cell, compared to the control cell. An “optimum ” series was tested experimentally and modeled with the HEED computer program in different California climate zones demonstrating potential savings for ratepayers.
A microcomputer-controlled thermostat has been designed that manages airflow according to cooling... more A microcomputer-controlled thermostat has been designed that manages airflow according to cooling needs in a building and resources in the environment. This system is an intelligent control system with both indoor and outdoor temperature sensors that uses rules to control a whole-house fan, in addition to the furnace and air conditioner. No such thermostat is currently available commercially. The most effective rule, proposed in a previous paper, was used to determine the effects of modifying the window area and the amount of mass. Results demonstrate the importance of adding mass and controlling solar radiation on a venting system that uses outdoor air-economizer cooling-. 1.
In the future of Computer Aided Architectural Design (CAAD), architects clearly need more then ju... more In the future of Computer Aided Architectural Design (CAAD), architects clearly need more then just computer aided design and drafting systems (CAD). Unquestionably CAD systems continue to become increasingly powerful, but there is more to designing a good building than its three-dimensional existence, especially in the eyes of all the non-architects of the world: users, owners, contractors, regulators, environmentalists.... The ultimate measure of a building's quality has something to do with how well it behaves over time. Predictions about its performance have many different dimensions; how much it costs to build, to operate, and to demolish; how comfortable it is; how effectively people can perform their functions in it; how much energy it uses or wastes. Every year dozens of building performance simulation programs are being written that can predict performance over time along any of these dimensions. That is why the need for both CAD systems and performance predictors can ...
A prototype microcomputer-controlled thermostat that can operate different systems in a building ... more A prototype microcomputer-controlled thermostat that can operate different systems in a building according to comfort requirements and resources in the environment has been developed by the authors. This intelligent control system has been tested measuring indoor and outdoor temperature to operate a fan and/or blinds. This paper presents some results of a study done in the summer of 2004, comparing the performance of the test cell operating with both the fan and shades with previous series in the summers of 2002 and 2003 with only either the fan or the shade operating. All of them were also compared to a reference cell without shades or fans. Other variables, such as the amount of mass and insulation levels are fixed in all series. Results indicate that in this climate all of these strategies help to achieve more comfortable conditions inside the experimental cell than the control cell but that some perform better than others. A higher air change works better than a lower air change...
In California there are 16 different climate zones as defined in the California Energy code (Titl... more In California there are 16 different climate zones as defined in the California Energy code (Title 24). The code requires slightly different types of buildings in each zone. These different building code requirements make it important for architects, builders, contractors, and homeowners to understand the resources of their unique local climate and how it will influence the performance of their buildings. The objective of this project is to create a tool called Climate Consultant 4.0 that adds a number of features to those in the prior version 3.0, including new graphic screens such as a Monthly Diurnal Averages plot. It also calculates a set of the Top 20 Design Guidelines based on your unique climate, and displays a sketch illustrating how each applies. A new dynamic graphic tutorial has been created to explain the Psychrometric Chart, and how the relationship between air temperature and humidity influences human thermal comfort and HVAC systems design. Climate Consultant 4.0 help...
The use of windows as passive solar collectors is discussed, and SOLAR-2, an interactive computer... more The use of windows as passive solar collectors is discussed, and SOLAR-2, an interactive computer-aided design program for designing an energy efficient window-sunshade assembly, is described. Windows with properly designed shading and orientation will supply a significant portion of a building's heating needs during the winter months and also exclude radiation and reduce cooling loads during summer months. The designing of a building's passive solar collector windows will be facilitated by the SOLAR-2 computer program which can deal with the computational complexity of evaluating each window's geometry, orientation, transmitting materials, shading devices, and construction details.
HEED (Home Energy Efficient Design) shows architects, builders, and homeowners how to design or r... more HEED (Home Energy Efficient Design) shows architects, builders, and homeowners how to design or remodel their buildings to reduce or even eliminate air conditioning loads. It is intended for use at the very beginning of the design process, when most of the critical decisions effecting energy consumption are made. This paper goes step-by-step through a typical building remodeling design using HEED. It shows graphically the differences in performance between various passive cooling alternatives including things like window shading, thermal mass, ventilation, improved envelope, and optimized shape and orientation, etc. Among the features users especially appreciate is the simple way they can draw in floor plans and how they can drag and drop windows onto each facade. HEED shows them bar charts comparing the difference in heating and cooling energy costs for up to nine different designs. The objective is to facilitate a simple, non-technical, smooth flowing, decision-making experience. ...
Phrases like solar heating, passive cooling, or energy-conserving design should be eliminated as ... more Phrases like solar heating, passive cooling, or energy-conserving design should be eliminated as quickly as possible from the vocabularies of all practicing architects. Such phrases should be replaced by the phrase ''competent design'' and simply taken for granted. Every client has a right to expect these features from a qualified professional just as they expect a structurally sound, fire-safe, and weather-tight building. In times past, indigenous builders knew very well how to design thermally efficient and energy-conserving buildings. They may not have understood the theory behind their designs, but the rituals, traditions, and cultural taboos governing their work embodied wisdom gained over the centuries. The elegance and thermal ingenuity of these buildings are still admired by even the most high-tech, post-modern architects of today.
Every design decision an architect makes carries with it a hidden environmental cost. Architects ... more Every design decision an architect makes carries with it a hidden environmental cost. Architects are concerned about issues like sustainability, greenhouse gas production, and other environmental costs, but there is little they can do until there is an easy way to visualize exactly what these costs look like. This paper describes a user-friendly microcomputer design tool that calculates the environmental costs of each architectural design decision, and then displays an easy-tounderstand picture of how these costs change from one design to the next. This new version of SOLAR-5 shows how a well designed passive building produces less air pollution and greenhouse gasses, and thus how it contributes to a more sustainable environment. Seven different atmospheric pollutants are included in the database, measured in pounds of pollution per KwHr for electric power generated and per MMBTU of natural gas or heating oil burned. SOLAR-5 also displays the amount of energy a building uses and its...
Energy efficient design requires different types of buildings in each different climate. This mak... more Energy efficient design requires different types of buildings in each different climate. This makes it essential for architects, builders, contractors, and homeowners to understand the resources of their unique local climate and how it influences the performance of their buildings. Climate Consultant 4.0 has been created to achieve this. It adds a number of new features, including new graphic screens and an interactive tutorial to explain the psychrometric chart. It also automatically creates a list of Design Guidelines based on the attributes of each unique climate and it then displays a sketch illustrating how each Guideline applies. Thus, Climate Consultant 4.0 helps people who are designing, constructing, and maintaining buildings anywhere in the world understand the resources of their local climate and how it impacts their building’s performance.
The new Oak Park Library Project has many kinds of clients, each of whom will in some way influen... more The new Oak Park Library Project has many kinds of clients, each of whom will in some way influence the final building design. A surprising number of these stake-holders represent different issues of sustainability including energy efficiency, and air pollution. This paper shows how a microcomputer design tool, SOLAR-5.4, is used during the Schematic Design Phase to simulate and display the performance of each different design scheme, in terms meaningful to each of the different groups of clients. SOLAR-5.4 is extremely fast and user-friendly. It is intended for use by architects at the very beginning of the design process when most of the basic decisions are made that later on turn out to have the greatest impacts on the building`s long term performance. The objective is to help the architect make the best possible decisions while the design is still in its formative stage.
A major interior landscaping project is a central component of a proposed corporate headquarters.... more A major interior landscaping project is a central component of a proposed corporate headquarters. While interior landscaping is a significant part of many such projects, typical plant losses of 20-40 percent each year are not acceptable for this installation. The client is confident of their ability to control important factors to sustain plant growth such as soil, irrigation, and plant compatibility. Daylighting for plants remains as the element most difficult to predict and control in an integrated manner in the interior environment. The architect proposed two different skylight designs. The study provides a methodology based on physical model testing and computer simulation using California Energy Commission (CEC) climate data that resulted in the required illumination level data for the architect during the early phases of project development.
In California there are 16 different climate zones, as defined in the California Energy Code (Tit... more In California there are 16 different climate zones, as defined in the California Energy Code (Title24). The code requires slightly different types of buildings in each zone. These different building code requirements make it important for people who are designing, building, or maintaining these buildings to understand the unique attributes of their climate and how it will influence the design and performance of their buildings. In this UCEI project we developed a simple, free, easy-to-use, graphic-based computer program called Climate Consultant 3, and we have posted it on the State of California’s Flex Your Power web site and on the UCLA Energy Design Tools web site. Our objective is to make it freely accessible to architects, builders, contractors, and homeowners, etc., to help them understand their local climate and how it impacts their building’s energy consumption.
In order to compare the performance of three different cooling strategies (External Operable Shad... more In order to compare the performance of three different cooling strategies (External Operable Shades, Internal Operable Shades, or a Whole-House Fan) in all 16 California climate zones, hourly performance data was recorded in a pair of full height test cells. The results were used to validate HEED (Home Energy Efficient Design), a whole-building energy simulation program. HEED automatically designed two 2000 sq.ft. houses, one to Meets the Energy Code, (Californias Title24), and the other that was a More Energy Efficient scheme. The Code requires a slightly different buildings in each of Californias 16 climate zones. On a state-wide basis these More Energy Efficient homes designed by HEED use about 35 % less energy than the homes that Meet the Energy Code (Title 24). One of the three cooling strategies was added to each of the two basecase homes in each climate In the Title 24 home the Whole-House fan is only half as good as either of the two Operable Shades. However in the More Ener...
The Psychrometric Chart tutorial is a downloadable animated tutorial application which explains t... more The Psychrometric Chart tutorial is a downloadable animated tutorial application which explains the various features of the Psychrometric Chart and how it illustrates indoor or outdoor air conditions and their relation to human thermal comfort. This tutorial is written in Flash and various audio-visual techniques are incorporated to create an effective educational resource. This paper outlines the underpinning developmental theories for the tutorial program and subsequently describes, in detail, each of the features it presents: dry bulb temperature, absolute humidity, saturation line, relative humidity, wet bulb temperature, dew point temperature, precipitation, hourly data, comfort zones, and mechanical systems. It is concluded with user feedback and indications of future enhancements.
ABSTRACT A prototype microcomputer-controlled thermostat was developed that can manage airflow ac... more ABSTRACT A prototype microcomputer-controlled thermostat was developed that can manage airflow according to cooling the needs in a building and the resources in the environment. This intelligent control system measures both indoor and outdoor temperature and uses decision rules to control a whole-house fan, in addition to the furnace and air condi-tioner. No such residential thermostat is currently commercially available. This paper presents the controller strategy that optimizes cooling with outdoor air. This paper also quantifies the effects of modifying the amount of thermal mass and the window area on indoor comfort when using this controller. These test confirm that smaller windows and more mass performed better than larger windows and less mass, and that higher volumes of controlled ventilation outper-formed fixed ventilation rates.
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Papers by Murray Milne