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Showing posts from July, 2017

16.07.2017 - PHYSICAL TOPICS OF BUILDING

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INSULATION Insulation control heat flow from outside to inside and inside to outside to keep indoor thermal balance. Opaque surfaces has to contain insulation these are walls, ceilings, roof, basement because surface temperature has to be conserved. Some of these insulations works for thermal, vapor, fire/smoke, sound resistance. Thermal resistance: conduction (transfer thermal momentum between molecules according), convection, radiation(light radiates  different amount of electro-magnetic energy than surfaces absorb that energy) Thermal resistance relates with R which is R=1/U so smaller U factor means better insulation. To obtain effective insulation, decrease U and k  (thermal conductivity) and insulation has to cover all surfaces of room from exterior to prevent thermal bridge by structural element s. THERMAL MASS Thermal mass works about resistance against heat fluctuation and storing huge amount of energy comes from solar radiation or convection but it does n

11.07.2017 - A.N.N. / PREDICTION MODEL

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Neural networks are generally used for the the aim to predict the of building energy consumption because they are capable to struggle the non-linear problems such as multi- objective equations. If the data set is enough to reach the logical result for fast-prediction at concept phase, A.N.N is suitable for this kind of tasks. As mentioned before Neural Networks occur wide historic data to form a function.   The first data are prepared to Train Data Set. This process works to construct a connection by data set. Although several parameters exist for the problem, A.N.N. can create good function between objectives.  The second data set are validated for pattern recognition,  and the last one is testing the data,which is necessary in the training and post-training processes in order to prevent the over-training in the ANN. Why it is important ? Overtraining means neural network completely learn the data and it can give any logical response if we add new data to data set after overtrainin

10.07.2017 - MODELING ENERGY SYSTEM

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Modeling Energy System Modelling energy model of close system occurs several elements these are wall,floor,ceiling,windows and doors, mechanical ventilation system, outside temperature and humidity level, lastly, peripheric elements situated around system. Besides that, openings positions, dimensions effects illumination and heat gain of the interior system, in addition with it, natural ventilation also helps to total energy need and refresh the indoor air quality. Although, model can not be completed for some reasons which are lack of data set content or data set don't work with dynamic model.   Mass and heat transfer laws helps the construct formulation between components of energy model and comfort index of interior. There are three main element to define comfort these are indoor air temperature ( ◦C ), indoor relative humidity( % ) and indoor CO2 concentration. Temperature The indoor air temperature model depends on heat transfer principles.  ASHRAE(2009) Inst

09.07.2017 - COMFORT CONTROL IN BUILDINGS

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Comfort in Buildings There are several comfort types in buildings. While think about comfort for the buildings, first idea always comes as thermal comfort but there are other issues related with comfort subjects for buildings. These are, in orderly, thermal comfort, visual comfort and indoor air quality.  Thermal comfort 'That condition of mind which expresses satisfaction with the thermal environment.'                                                                                                               Fanger, 1973  Thermal comfort constitutes form different elements. 4 of them can be calculated by sensors easily, which are  air temperature (◦C), radiant temperature (◦C),  indoor air velocity (m/s) and air relative humidity (%). The other hardly calculated factors depens on humans perception these are clothing insulation (m2 ◦C/W) and metabolic rate (W/m2). To calculate thermal comfort,  Predicted MeanVote (PMV) index, developed by Fanger, during the 197

02.07.2017 - YDS (TÜRKÇE)

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22 temmuz temmuz tarihinde e-yds sınavı için Ankara'ya gideceğim. Aşağı yukarı 20 günlük zaman süresince kendimi 3 gün de bir çalışmaya programladım. Aşağıda belirlediğim stratejilerde de anlatılacağı gibi, önceki yds sınavları üstünden bir çalışma sistemi deneyeceğim. Amacım 90 puanlara yaklaşabilmek. Bunun için minimum 5 sınavı ortalama 150 dakikadan çözmeyi planlıyorum. Böylece son yarım saatte kontrol hakkım olabilecek. Hedeflerim sırası ile şöyle :  hedef bir puan belirle: 90 puan (hedef motivasyonu arttırır) soru kitapçığı al ve sınavlardaki hataların üstünden ilerle (böylece spot bilgiler hedeflenir) minimum 5 test çözmeli (en yeni tarihli 5 sınav) sınavda zaman kazanmak için 150 dakikalık süre tut. bilmediğin kelimeleri işaretle ve öğrenmeye çalış. hatalarını kontrol et ve üst üste aynı konu soru tipinde hata yaparsan onu çalış. videoları izlemek önemli. Reference Link :  https://www.youtube.com/watch?v=aspCZcRJmQE&t=10s&list=PLbs896PAcgWbb_SuAbcyV1lVI

01.07.2017 - THERMODYNAMICS - DESIGN BUILDER - ALTENSIS

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To understand building energy need, it needs to take a look into basics of energy about heat transfer and types, thermodynamic laws, differences between temperature and heat. So you can check the 'crash course' youtube channel page about it. I assume that watching is more catchy than reading.   Thermodynamics: Crash Course Physics #23  thermo dynamics firts law --> internal energy  = heat - work    ( ∆ u = q - w )  thermo dynamics second law --> heat flow from hotter space to colder space  entropy --> the more disorder the more entropy --> universe has tendency to increase entropy (solid -> liquid -> gas) The Physics of Heat: Crash Course Physics #22  thermal energy (U) = internal energy = heat - work    ( ∆ u = q - w )  heat transfer (Q =m.c. ∆ T ) temperature and phase changes (Q =m.c. ∆ T and Q=m.L) thermal conductivity (K)  conduction (solid-solid heat transfer) / convection (liquid,gas heat transfer) / radiation (heat transfer by