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"ABSTRACTRe-suspended road dust is an important contributor to ambient particulate matter (PM) particularly in an area where fugitive dust is a dominant emission source. This study evaluated PM-10 emissions as fugitive re-suspended dust from the road network in the Na Phra Lan pollution control zone, Saraburi, Thailand. Emissions of road dust were determined by using the analysis of silt loading and physical characteristics of the roads located in the study area. These data were used together with those emissions from point and area sources in the study area to predict the ambient concentrations of PM-10. AERMOD model was applied to predict PM at various receptor points. Source contribution of each emission group to PM-10 ambient concentrations at each receptor were evaluated. Predicted 24 hours PM-10 concentrations at 8 sites from the total of 23 receptors were higher than the PM-10 ambient air quality standard (> 120 μg/m3). Results revealed that line sources played an important role in contributing to the PM-10 concentrations in this pollution control zone. The highest predicted PM-10 concentration at the receptor was evaluated to have about 71% contribution from mobile source emissions. Therefore, the effort to manage and control emissions of re-suspended road dust could be strengthen for further success of the air pollution control in this area."

""Nous savons que dens la plupart des societes du mon¬de musulman, la veneration des ""saints"" et des ""tombeaux sacres"" joue un rOle fondamental clans la pratique du culte. Ce phenomene ne se vtrifie pas seulement pour les adeptes du shi' isme ou ii est tres deveioppG meis egaiement parmi les sunnites comme par exemple en Afrique du Nord evec le maraboutisme. (1) Dens le cis de 1'Indonesie, 1' existence d' un tel culte est encore renforcee par is forte impregnation des survivances preislamiques - comme d'ailleurs, A des degres divers, it est vrai difficile A eppre¬tier, clans n'importe quel pays musulman - autrement dit, du culte des ancetres, s'exp.rimant A travers 1'importance accor¬dee aux coutumes funeraires, et en particulier A tout ce qui est en rapport avec ies selamatan ou repas communiels commemo¬ratifs.Par eiileurs, comme nous le montrera 1'histoire de la penetration de 1'Isiam en Indonesie, la civilisation des pays ayant servi d'intermediaire - tel notamment que 1'Inde1) A ce sujet, cf. E.Jermenghem, i__ culte des saints dams l' Islam mactrc'bin, Gallimard, Paris 1954. Eyalement clans une opticue plus gen`rnle encore, c.Westermarck, Survivances pal¬enres dins la civilisation mahometene,, trad. de R.Godet, Paris 1935""

"Modelisasi numerik dinding batu pecah pada umumnya dilakukan dengan menggunakan program berbasiskan elemen hingga. Pada penelitian ini, dinding batu pecah dimodelisasi dengan elemen diskrit sedemikian sehingga tegangan pada struktur dapat diskontinu dan elemen struktur memiliki bidang geser diantara elemennya. Penelitian ini bertujuan untuk mengkonfirmasi model numerik elemen diskrit untuk modelisasi dinding penahan tanah dengan batu pecah. Modelisasi numerik dilakukan berbasiskan pada hasil eksperimen dinding penahan tanah berukuran kecil yang dibebani dengan batang duralium yang dikenal dengan Schneebeli?s rods. Setiap blok penyusun dinding dimodelisasi terlebih dahulu kemudian dilakukan uji geser langsung secara numerik yang hasilnya dibandingkan dengan hasil percobaan. Blok penyusun dinding dibuat rigid, tujuan utamanya untuk mempercepat proses kalkulasi, selain itu juga menyesuaikan dengan hasil percobaan dimana elemen blok tetap utuh sebelum dan sesudah uji pembebanan. Model numerik dinding penahan tanah dibuat dengan PFC 2D, dimana setiap blok penyusun dinding memiliki dimensi yang sama namun dengan rugositas yang berbeda. Dinding dibuat dengan menumpuk blok secara berselang-seling baris demi baris hingga tercapai tinggi dinding yang diinginkan. Pembebanan dilakukan pada salah satu muka dinding penahan tanah. Hasil simulasi menunjukkan bahwa modelisasi menggunakan metode elemen diskrit pada dinding penahan tanah dengan batu pecah mampu memberikan hasil yang relevan dengan hasil percobaan.

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In past research, the modelisation of dry stone retaining used a software based on the finite element method. In this research, the dry stone retaining wall were modelized with the discrit element method, thus the stress could be discontinu and the structural element has a slip plane. This research had taken in order to confirm the numerical model using the discrit element method to model the dry stone retaining wall. Numerical model were built based on the experimental test of small-scale retainng wall which were loaded with the duralium rod named Schneebeli?s rods. Every block were modelized beforehand, then it is tested with a numerical direct shear test where the results is compared with the experimental test. The block were modelized as rigid block, so the calculation time can be reduced, furthermore it adapts the real model where the block before and after the loading test were still intact. Numerical model are modelized with PFC 2D, where every blocks of the wall has the same dimension but different rugosity. The wall were created by stacking the block consecutively until it reached the desired height of wall. Load were exerted at one of the dry stone wall faces. The simulation results shows that the modelisation using the discrit element method for dry stone retaining wall gave a reasonably good results compared to the experimental test."