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Placic (Bsm) horizons are commonly found in different types of soils worldwide, but are very rare in Ultisols. The formation of Bsm horizon and podzolization are different processes in pedogenesis. This study collected five podzolic Ultisols containing Bsm horizons from the subalpine forests in Taiwan to illustrate the morphological characteristics and genesis of the Bsm horizons in these soils with both clay illuviation and podzolization. The distinctive Bsm horizons were 3 to 10 mm thick and had abrupt and wavy boundaries with overlying albic (E) and underlying argillic (Bt) horizons. All Bsm horizons contained over 35% of clay fraction which significantly increased from E horizon to B horizons in the pedons. The Bsm horizons showed much higher bulk density than adjacent horizons above or below them, elucidating that such iron pans were relatively impermeable to water and plant roots. The maximum contents of pedogenic Fe occurred in the Bsm horizons mainly cemented by poorly crystalline Fe oxides associated with high amounts of organic matter and epiaquic conditions. Pedogenic Al appeared to be accumulated in the Bt horizons where spodic materials were identified according to the oxalate-extractable amount of Fe and Al. The polygenetic processes of these podzolic Ultisols with Bsm horizons were proposed as three stages. Firstly, clay illuviation predominantly occurred to form Bt horizon in the interglacial periods during the mid to late Pleistocene. Then, podzolization gradually became a major process to accumulate spodic materials in the Bt horizon because of the coniferous forest formation under the cool and humid climates close to the late Pleistocene; however, water was perched at the soil surface due to poor drainage and abrupt textural change between E and Bt horizons after the Holocene. Eventually, the reduced iron from E horizon was gradually re-oxidized and precipitated on the top of Bt horizon where exhibited oxidizing condition to form Bsm horizon until today. Because of the occurrence of Bsm horizon in these Ultisols, a new subgroup Placic Epiaquults, was therefore proposed to the keys to Soil Taxonomy.

An information tracking system of the liquefied petroleum gas industry is important to the government in carbon emissions economics. This research applied an information tracking system to the liquefied petroleum gas industry. It also formulated finding a minimization unexpect LPG quantity (Gap), and auto plot the variation by time of a selected firm using html5 techniques, which unexpect LPG quantity (Gap) was over the predefined threshold. Through a web-structure dynamic tracking system, a manager can easily access the information of unexpect LPG quantity (Gap) firms. Future research suggests expanding this research to physical tank constraints calculation.

Data mining is a hot research topic over the last twenty years or more. In recent decades, network graphs that have represented knowledge of a focus topic have gained increasing attention. These maps include term network, concept map, topic map or knowledge map. A concept map is one of the visualization tools to show the relationships among concepts. It is a graphical tool for organizing and representing knowledge. Global warming poses a grave threat to the world’s ecological system. Economic development has led to a huge increase in energy demand and therefore energy efficiency and saving has become a key issue for most countries. In many countries, they tried hard to find renewable and sustainable energy supplies and sources. This study tries to analyze trends of energy policy literatures from the international literature database within last three years to be visualized in 3-D concept map layouts; besides, measuring keyword relation linkages though control variables of concept maps, such as size of node, linkage, relations and dynamic figure layout, are the main contributions to academics. This research adapts an IP (integer programming) model to maximize relation linkages for each node among a term network. The more linkages, the more useful information offered for mining knowledge from a term network. The 3-D concept map was demonstrated. Future research suggests applying this approach to other research literatures from international literature databases.

A class of nanoporous TiO2 gas sensors processed by novel anodic aluminum oxidation (AAO) of Al thin films and microelectromechnical systems (MEMS) techniques are presented. To enhance the sensitivity and reduce the sensing dimensions of a gas sensor, a nanoporous surface of the gas-sensitive material on the sensor is required. These sensors can be implemented on silicon or silicon dioxide substrate featuring a thin membrane of micro-hotplate structure featuring micro-heaters, thermometers and electrodes, and thus operate as chemoresistive devices. Combining the AAO method with dry-etch process, a homogeneous and nanoporous SiO2 surface of the sensor can be effectively configured by modulating various hole diameters and depth, hence replacing conventional photolithography and electrochemical etch. The process integration including AAO, reactive ion etch (RIE) and microfabrication is mainly developed and a feasibility study of PVD TiO2 thin film deposition upon the porous device is also provided. TiO2 thin films deposited on the nanoporous surface are investigated and compared with non-porous TiO2 films. It is encouraging that our fabrication process is able to provide relatively high surface area to enhance sensitivity of the sensor without additional doping steps. Our promising experimental results have revealed these miniature and cost-effective devices are not only compatible, but applicable to smart bio-chemical sensors of next generation.

Three pedons of Inceptisols with placic horizons were selected to study the characteristics and genesis of subalpine forest soils located in Shang-Hsing Mountain in Ilan county, northeastern Taiwan. The selected pedons were elevated from 1900 to 2100 m and derived from slate formed in the late Quaternary age. The vegetation types are dominated by red cypress (Chamaecyparis formosensis Matsum) and Taiwan Chinese fir (Taiwania cryptomerioides Hay). The annual rainfall is about 3000 mm and mostly falls from April to October. The soil moisture regime is perudic, and the soil temperature regime is mesic. Three Inceptisols can be classified as Lithic Dystrudept and Oxyaquic Dystrudept based on USDA Soil Taxonomy or Cambisol based on World reference base system. Clear illuvial pedogenic processes were observed by the bleached albic (E) horizon and the underlain placic (Bs) horizons, which were characterized on the changes of soil morphology, micromorphology, soil texture and chemical compositions. The placic horizon appeared to be dominated by amorphous iron and free iron oxides, with lesser amounts of amorphous aluminum and free aluminum oxides. The genesis of the placic horizons in the study area was proposed as two stages. In the first stage, the perched water was located between albic horizon and cambic horizon after a storm owing to the texture changes of these two horizons. In the second stage, Fe of the upper part of the pedon was reduced, then be mobilized and reoxidized it in the boundary of E and Bw horizon. Therefore, the boundary of placic horizon has a wavy or irregular boundary. In addition, the genesis of placic horizon may also relate to the precipitation of mobile Fe at higher soil pH value and oxidizing soil contacts below the mineral soil surface. Although we do not find the argillic horizon formed below the placic horizon, Ultisols are a major soil order formed in the level landscape position of the study area.