TYIN tegnestue Architects. Integrating On-Site Education and Practice

Founded by Andreas Grøntvedt Gjertsen and Yashar Hanstad, TYIN tegnestue Architects grew out of an initiative to provide sleeping accommodation for an orphanage in Thailand when the principals were only third-year architecture students. Norwegian architect Lisbet Harboe explains how the student-architects built up a practice while in schools by refocusing their studies and those of their peers on learning through their own experiences of construction.     

Integrated energy and carbon modeling with a decision support system: Policy scenarios for low-carbon city development in Bangkok

Energy use in Bangkok accounts for a large portion of the total energy consumption in Thailand. Few energy and carbon studies, however, have focused on the level of the city. International research indicates that cities are the key drivers of energy usage and the associated carbon emissions. This paper presents a study on the options for energy and carbon development for the city of Bangkok. The Long-range Energy Alternatives Planning System (LEAP) model is used to simulate a range of policy interventions and to predict how these would change energy and carbon development from 2000 to 2025. The planning period is assumed to start in 2005, and 2000 is used as the baseline year. Sustainability of the sixteen proposed policies and scenarios is analyzed using a multi-criteria decision-making approach. Results of this study provide an insight into Bangkok's energy and carbon future and highlight the steps required to promote a sustainable low-carbon society. The most significant energy savings are in the transport sector, where a modal shift from private passenger vehicles to mass transit systems has the potential to significantly reduce energy demand, carbon emissions, and local air pollutants.     

Measured and predicted performance of prefabricated vertical drains (PVDs) with and without vacuum preloading

This paper presents the effectiveness of vacuum preloading in accelerating the consolidation of PVD improved soft Bangkok clay by comparing with the corresponding results without vacuum preloading. Laboratory tests were conducted using a large scale consolidometer having diameter of 300 mm and height of 500 mm with reconstituted specimens installed with prefabricated vertical drains (PVD) with and without vacuum preloading. In addition, field data were collected from Second Bangkok International Airport (SBIA) site improved by PVD with and without vacuum pressures. Analyses were carried out to compare the compressibility parameters (C_h and k_h/k_s) by back-calculation of laboratory and field settlements using Hansbo (1979) method. From the laboratory tests, the horizontal coefficient of consolidation (C_h) values from reconstituted specimens were 1.08 and 1.87 m²/yr for PVD without and with vacuum pressure, respectively and the k_h/k_s values were 2.7 for PVD only and 2.5 for vacuum-PVD. After the improvement, the water contents of the soft clay were reduced, thereby, increasing its undrained shear strengths. Similarly, the field data analysis based on the back-calculated results showed that the k_h/k_s were 7.2 and 6.6 for PVD without and with vacuum, respectively. The C_h values increased slightly from 2.17 m²/yr for PVD only to 3.51 m²/yr for vacuum-PVD. The time to reach 90% degree of consolidation for soils with vacuum-PVD was one-third shorter than that for soils with PVD only because of higher C_h values. Thus, the addition of vacuum pressure leads to increase horizontal coefficient of consolidation which shortened the time of preloading. The PVDCON software was found to be useful to predict the settlements of the PVD improved ground with and without vacuum preloading.     

PVD improvement combined with surcharge and vacuum preloading including simulations

This paper presents the study of PVD improved reconstituted specimen with and without vacuum preloading on large-scale consolidometer in the laboratory tests. Subsequently, the results of the laboratory tests were analyzed and simulated by 2D (axisymmetric) finite element method (FEM) to back-analyze and confirm the related design parameters which were used further in subsequent numerical experiments. The laboratory test results indicated that the increased hydraulic conductivity in the smear zone of PVD with vacuum preloading (Vacuum-PVD) resulted in the increase in the coefficient of horizontal consolidation (Ch) by 16% as well as the decrease in the ratio between the horizontal hydraulic conductivity of the undisturbed zone (Kh) to the horizontal hydraulic conductivity in the smear zone (Ks) or (Kh/Ks) of about 10%. The Vacuum-PVD and PVD only have the same settlement magnitudes with similar equivalent loads.     

合金元素对铝合金在泰国曼谷地区初期腐蚀行为的影响

在泰国曼谷地区对5083、6063和7020 3种铝合金进行为期1 a的暴晒实验,采用SEM、电化学实验、XPS和扫描Kelvin探针显微镜(SKPFM)对3种铝合金初期腐蚀形貌及腐蚀机理进行研究。结果表明:6063铝合金中Mg、Si、Fe等合金元素含量较少,腐蚀电位相对较高,约为-0.66 V (vs SCE),腐蚀产物膜较为致密,耐蚀性较好,在泰国曼谷地区的腐蚀速率约为0.7 g/(m^2·a)。7020铝合金含有较多Mg、Zn等合金元素,腐蚀电位约为-0.78 V (vs SCE),腐蚀最为严重,腐蚀速率约为3.26 g/(m^2·a)。3种铝合金均含有Mn、Si、Fe等合金元素,从而形成Fe-Si-Al或Fe-Si(Mn)-Al第二相,第二相表面电位高于基体225~280 mV,在大气环境中第二相作为阴极相,周围的基体Al优先溶解脱落,成为点蚀坑。     

SAI Consultants

The work of Bangkok-based Bundit Chulasai runs the full gamut of building types from palace restorations to private houses, resorts and even discount supermarkets. Brian McGrath describes how Chulasai's ‘successful “adaptive practice” with SAI Consultants creates a critical mirror to reflect the last 30 years of Thai society’. Copyright © 2009 John Wiley & Sons, Ltd.     

Adsorption of Photographic Sulphur Sensitizers to Silver Bromide and Silver Sulphide

Heats of adsorption of thiosulphate, thiosulphatoargentate and p-toluenethiosulphonate to silver bromide, silver bromo"dide, silver chloride and silver sulphide were measured using a slow microcalorimeter. The results did not confirm previous evidence for the cluster mechanism for silver sulphide formation during sulphur sensitization. The possibility of this model was discussed. Heats of adsorption of silver and sulphide ions were also measured.     

Airborne Polycyclic Aromatic Hydrocarbons (PAH) in Bangkok Urban Air: Part II. Level and Distribution

The gas-particle partitioning and particle size distributions of airborne PAH in Bangkok urban air were investigated using an 8 stage size fractionating cascade impactor (Andersen “low volume” sampler) and a downstream XAD-2 adsorbent tube for sample collection. Nine PAH classified as carcinogenic and co-carcinogenic compounds-Pyrene (PYR), Benz(a)Anthracene (BaA), Benzo(e)Pyrene (BeP), Dibenz(a,c)Anthracene (DBacA), Benzo(k)Fluoranthene (BkF), Benzo(a)Pyrene (BaP), Dibenz(a,h)Anthracene (DBahA), Benzo(ghi)Perylene (BghiP) and Trimethylcholanthrene (3MC) - were quantified. The lower molecular weight (MW) PAH such as PYR, BeP and BaA were present mainly in the gaseous phase (80%, 40% and 24%, respectively) while higher MW compounds were present almost totally in the particulate fraction. The results show that 30%–60% of each PAH by mass were found on particles smaller than 0.43 μm and more than 70% on particles with diameter less than 2.1 μm. In addition, the relationship between the particle/gas partition coefficient (K _p ) and the sub-cooled liquid vapor pressure (p°_L) was also determined to describe the gas-particle partitioning of those PAH compounds in a tropical atmosphere.     

Biodegradation of domestic wastewater under the simulated conditions of Thailand

Serious concerns have been raised about the sustainability of conventional mechanized linear wastewater treatment systems in the developing world. Bangkok in Thailand is no exception to these concerns, and merits closer examination. This paper is aimed at unveiling the fundamental facts and characteristics relating to the organic degradation potentials of domestic wastewater in Bangkok. It is supported by evidence from simple laboratory experiments in which existing local conditions were simulated. The results showed that greywater‐like qualities of domestic wastewater do predominate in Bangkok, most probably as a result of three main factors: (1) continued use of leaching septic tanks, (2) the tradition of using water after defecation, instead of toilet paper, and (3) high organic degradation potentials under tropical monsoon conditions. Considering the small organic content, coupled with high organic degradation rates of the freshly collected greywater‐based sewage in Bangkok, low‐cost and decentralized natural treatment systems could be far more suitable for environmental sustainability in such tropical monsoon areas than the implementation of large‐scale sewage works.     

Effect of synthesis time on morphology of CeO_2 nanoparticles and Au/CeO_2 and their activity in oxidative steam reforming of methanol

Ceria(CeO_2)supports,synthesized by hydrothermal treatment with different synthesis time(CeO_2-X h,where X is the synthesis time in h)in the presence of the surfactant cetyltrimethyl ammonium bromide,were used as supports for gold(Au)catalysts.The synthesis time significantly affects the morphological structure and crystallite size of CeO_2,where CeO_2-2 h has the smallest crystallite size with coexisting nanorods and nanoparticles.Transmission electron microscopy analysis confirms the morphology of CeO_2 with distinctive(110),(100)and(111)planes,in agreement with interplanar spacings of 0.19,0,27 and 0.31,respectively.However,the morphology of CeO_2-8 h and CeO_2-48 h is mainly a truncated octahedral with crystal planes(111)and(100)accompanied by an interplanar spacing of 0.31 and0.27 nm,respectively.The CeO_2-X h supports and those with a 3 wt%Au loading(Au/CeO_2-X h)were investigated in the oxidative steam reforming of methanol at temperatures between 200 and 400 ℃.The Au/CeO_2-2 h gave the highest methanol conversion level and hydrogen yield at a low temperature of 250 ℃.This superior catalytic performance results from the good interaction between the metal and support and the well-distributed Au species on the CeO_2 support.