The Use of Computer Simulation Program in Urban and Architectural Research

Simulation is a method to describe a system by developing a model of the system and perform a series of trials to estimate the behavior of the system at a certain time. Simulation method is done if the field observation of the research object is not possible. Simulation method does not yield a way to solve the problem directly but only evaluate a few alternative solutions to solving the problem. Along with the development of computer technology, the simulation method also uses computer technology primarily to help calculate a mathematical model. Some researchers in the field urban and architectural research has used simulation methods to solve the existing problems. This is because the object is an object of architecture and urban are very large and complex that it is impossible to conduct an experimental modification to the object of study. Some researchers are using computer simulation method is Satwiko (1998), Jesionek and Bruse (2003), Shasua-Bar, et al (2005), Kusumawanto (2007), Nugroho (2007), and much more.

Groat and Wang, 2002 reminds some factors to be considered in the simulation are:

- Accuracy of the model

- Completeness of data input

- The resemblance to reality

- The cost and workability

Various programs have created a computer simulation model to assist with the research theme of the relationship between architecture / urban micro-climate conditions. The basis of calculations used by the simulation model program were from the empirical, as CTTC Model (Shasua-Bar, Hoffman, 2000) as well as numerical or mathematical calculations, such as CFD, etc. ENVImet. While there is scope in terms of the nature of 2D and 3D. ENVImet is one program that is a 3D simulation.

Hot Humid Tropic Urban Climate Characteristic

For the purposes of architecture and urban planning and design, climate as most appropriate classification is based on considerations of human comfort (Szokolay, 1979). Based on these considerations, the climate is divided into;

• Climate (cold climates) where the main problem is the lack of hot almost all year round. Area with this climate lies in the polar regions.
• Moderate climate (moderate climates), where there is seasonal variation between the time when the excessive heat (overheating) and the lack of heat (underheating).
• The hot dry climate (hot dry climates), where there is excessive heat (overheating), but dry air
• Warm, humid climate (warm humid climates), where the main problem is excessive heat (overheating) and high humidity.

Tropical region is a region that lies between the Tropic of Cancer (23.5 ° N) and the Tropic of Capricorn (23.5 ° S). In regard to the climate, the "tropical" is an area located between 20 ° C isotherm line in the northern and southern hemisphere. (Lipsmeier, 1994). Tropical climate is divided into 2 (two) major climatic regions, namely the tropical humid and dry tropics.

Solar radiation is the main factor of all the general features of climate (Lipsmeier, 1994). Areas with a humid tropical climate receives average solar radiation - the daily average larger than other regions. This causes the humid tropics have different average temperature - the average annual low (2-3 ° C) while the average temperature difference - average daily high (8-9 ° C). Highest temperature reached about - about two hours after noon, because at that time joined the direct solar radiation and the temperature is already high.

The amount of solar radiation also causes evaporation of water so the moisture in the humid tropics is higher. The higher the temperature the greater the water vapor that can be conceived to approach the saturation point.

Urban Open Space Typology

Open space in a city is part of the urban space. In general, a typology of open space can be grouped into
- Geometric shape (Zucker, 1973; Krier, 1979; Moughtin, 1992)
- Function (Krier, 1979; Moughtin, 1992)
- Characters (Car, 1992)
- Degree ketertutupannya (Spreiregen, 1965)

Geometric form of urban open space is divided into two groups: square and street (Krier, 1979; Moughtin, 1992). Square is a form of urban open space that is static, such as squares, playing fields and city parks that usually are centered and inward looking. While the street is dynamic, linear oriented at both ends, such as roads, pedestrian paths and so on.

The basic square shape according to Krier, 1979, derived from basic geometric shapes are triangles, rectangles and circles. Modification of the form - the basic form is a concern with the technique of angled space, segment of the basic element, overlapping / merged, adding to and distortion.

Physical quality of urban open space is determined by the degree ketertutupannya / enclosurenya level (Moughtin, 1992). This degree of closure will affect the meaning of a place. Degree of closure is determined by the ratio of the height (H) around the building and the wide open spaces (D) of the open space. Quality enclosure according Spreiregen, 1965, namely:
- H: D  < 45: full enclosure
- H: D <30: treshold enclosure
- H: D <18: keterlingkupan minimum enclosure
- H: D <14: loss of enclosure

Urban Heat Island Phenomenon

"A Heat Island" is an area where the ambient temperature is higher than the surrounding temperature. The high temperature will increase the demand of electricity for refrigeration and air conditioning to increase the production of carbon dioxide and other pollutants. These pollutants will eventually play a role in rising global urban temperatures.

Urban Heat Island phenomenon is characterized by spatial and temporal variations related to climate, topography, physical layout and short-term weather conditions. Urban Heat Island is very strong pattern is controlled by the unique characteristics of each city. Factors that influence the Urban Heat Island effect them;

• Geometry of the hallway that lowers radiation shortwave radiation due to the displacement of the alley way between buildings and complex filtering the sky. Infrared radiation emitted from a variety of buildings and the road surface.
• The nature of the heat storage material that increases the sensible heat to the surface of the city during the day and release heat to the atmosphere of the city at night.
• The release of heat from fuel combustion from vehicles or other sources and animal metabolis
• The greenhouse effect that contributes to increase the acceptance of long-wave radiation from atmospheric-polluted city.
• Decrease in surface evaporation in the city led to increased sensible heat and latent heat decrease.

Some studies show a direct relationship between density and population of a city and the intensity of the Heat Island effect. Urban land use and the closure of the surface also influences the Urban Heat Island effect. Temperatures in the city center where there is usually a function - the function of commercial and office with the closing of the land, recorded higher than other functions. Hashim and Nugroho, 2003, reported that the temperature in the center of Malang with office and commercial functions, higher than the surrounding area. Research conducted Stabler, 2005, in the state of the United States Phoenics also shows that urban microclimate associated with land use.

Typology as Methode in Urban and Architectural Research

Typology (in urban planning and architecture) is the taxonomic classification of (usually physical) characteristics commonly found in buildings and urban places, according to their association with different categories, such as intensity of development (from natural or rural to highly urban), degrees of formality, and school of thought (for example, modernist or traditional). Individual characteristics form patterns. Patterns relate elements hierarchically across physical scales (from small details to large systems).

Book Review : Urban Design Typologies, Process and Products

“A good city is not a result of individual, independent and selfish decisions”

(Enrique Penalosa, Mayor of Bogota)

The city is a collage of overlapping precincts, places and linkages (Rowe and Koetter, 1978). How should these elements be designed and organized? Is the urban design a product or a process? This book is not only to provide a typology of procedures and products of the urban design field but also to present a number of case studies that illustrate the range of interpretations of urban design.
This book is written by Jon Lang, a master in urban development and design program of University of new South Wales Sydney, Australia. The book is consist of 4 (four) comprehensive parts. Part I is the nature of urban design and urban designing. In this first part, the author discusses the public realm of cities and urban design, urban design process and the evolving typology of urban design process.

Second part of the book provides a clear explanation about traditional urban design process and product. This part is completed with various case studies from around the world.
The core of the book is present in the third part of the book. There are four typologies of current work of urban design process and procedures which are total urban design, all-of-piece urban design, piece-by-piece urban design and plug in urban design. All of these typologies explanation come with number of case studies each.
The future of urban design is the last part of the book. In this part, a visionary thought about urban design is presented.

Definition of Architectural Research

Definition of Architectural Research is the search for new knowledge and new ideas about the built environment. Research can be conducted in a variety of sub disciplines, including building technology, environment-behavior studies, history of architecture and computing technology. (Ahrentzen, Betrabet, Dally Geboy, and Dearborn-Karan, 2001).

Groat and Wang (2002, pp.6-7) repeat this definition that encompasses systematic inquiry and new knowledge, and rightly acknowledge that the development of architecture from earliest times has involved forms of research activity.

Building as physical products of function in a number of independent but interactive ways- they are structural entities, they act as environmental modifiers, they function socially, culturally and economically. Each of these types of function can be analyzed separately but the built form itself unifies and brings them together in such a way that they interact.  Architectural research thus has to be conscious of these interactions across traditionally separate intellectual fields.

Based on these interactions, the scope of architectural research can be divided into three stages:

-          Architectural Processes

-          Architectural Products

-          Architectural Performances