A web-based system for design interface management of construction projects

Planning methods such as CPM and PERT cannot model the iterative details of design processes. It has been demonstrated that the Dependency Structure Matrix (DSM) is an effective method to model iterative process. However, formulating the DSM on large construction projects, using current methodologies is challenging. To address this challenge, a structured methodology called Design Interface Management System “diMs” has been proposed. As the documents and interactions required for implementing the “diMs” process are voluminous, support of an IT based tool is essential. This paper presents the design and the development of the tool. It includes the design of class structure, relational database and communication engine using object oriented concepts. In addition, the design of user interface which consists of a set of dynamic web pages is also explained. The paper also illustrates the usage of the tool for the design of a glass factory and discusses the utility of the tool in assisting design interface management.     

Optimal Design of Tapered Microirrigation Submain Manifolds

An optimal design method for a drip submain manifold is presented. The optimal design is based on the shortest route algorithm for acyclic networks. Different route lengths are represented by total annual costs of different pipe sizes between two successive laterals. An example is solved to compare the method with an existing graphical method.     

Absorption characteristics of ocean water in the Arabian Sea during winter bloom from in situ measurements and Oceansat 2 OCM and MODIS data

In the northern Arabian Sea, blooms usually occur during the northeast monsoon (November–January) and inter-monsoon (February–April) periods. After death, these phytoplankton blooms produce massive subsurface zones of low dissolved oxygen levels that have a major impact on the ocean water ecosystem. Many studies have been done to identify the bloom in this region, but those on the optical properties of bloom water are scarce. The present study emphasizes the optical properties (inherent) of the bloom water in the study region using in situ and satellite data. The total absorption coefficient of ocean water was measured from in situ radiance data collected in the northern Arabian Sea from the Sagar Sampada cruise (SS-286) during March 2011. The same data were also derived from the top-of-atmosphere radiance and remote sensing reflectance of the Oceansat 2 Ocean Colour Monitor (OCM-2) and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) sensors, respectively. A comparison between measured (in situ) and retrieved total absorption coefficients from OCM-2 was made. The measured and retrieved absorption coefficients are in good agreement. Root mean square errors between measured and retrieved absorption coefficients are 0.018 m^?1, 0.026 m^?1, and 0.034 m^?1 for 490 nm, 510 nm, and 555 nm, respectively. An inter-comparison of total absorption properties retrieved from OCM-2 and MODIS data in the region of one degree radius around the stations was also made. A fairly good match was observed on 10, 14, and 16 March 2011 (coefficient of determination, R² = 0.75, 0.87, and 0.62, respectively) for the blue band (490 nm) and (R² = 0.77, 0.79, and 0.71, respectively) the green band (555 nm). The study demonstrates the potential of using remote-sensing optical data for identifying bloom waters.     

Structural and electrical studies of CeO2 modified lead zirconate titanate ceramics

The present study is an investigation of the structural and electrical properties of solid solution processed lead zirconate titanate (PZT) ceramics modified by CeO₂. The PZT composition studied is Pb(Zr_0.535Ti_0.465)O₃ modified with 0.0–0.2 mol % CeO₂. Studies of the loss of lead oxide during sintering have been performed. The lead loss increases with increasing Ce in the sample up to 0.1 mol % Ce and becomes nearly constant on further addition of Ce. The lattice parameters and cell volume of the tetragonal phase of PZT also increase with addition of Ce up to 0.1 mol % Ce. The lead loss and X-ray data indicate that Ce is being reduced to Ce³⁺ and is going onto the A-site of the PZT perovskite system. The study concludes that controlled modification of the MPB composition of PZT using 0.1 mol % CeO₂ results in substantial enhancement of piezoelectric strain coefficients, dielectric constant and electromechanical coupling coefficients.     

Effects of pH and cationic and nonionic surfactants on the adsorption of pharmaceuticals to a natural aquifer material

A wide range of pharmaceutical compounds have been identified in the environment, and their presence is a topic of growing concern, both for human and ecological health. Adsorption to aquifer materials and sediments is an important factor influencing the fate and transport of pharmaceutical compounds in the environment. Surfactants and other amphiphiles are known to influence the adsorption of many compounds and may be present in the environment from wastewaters or other sources. The work described here examines the adsorption of four pharmaceutical compounds, acetaminophen, carbamazepine, nalidixic acid, and norfloxacin, in the presence of a natural aquifer material. Adsorption was studied as a function of pH and in the presence and absence of two surfactants, cetylpyridinium chloride (CPC), a cationic surfactant, and Tergitol NP9, an ethoxylated nonionic surfactant. In the absence of surfactants, results indicate a 1-2 orders of magnitude variation in adsorption affinity with changing pH for each of the two quinolone pharmaceuticals (nalidixic acid and norfloxacin) but no measurable adsorption for carbamazepine or acetaminophen. In the presence of surfactants, adsorption of acetaminophen and carbamazepine was enhanced to extents consistent with compound hydrophobicity, while adsorption of nalidixic acid and norfloxacin was not. At high pH values, the anionic species of nalidixic acid exhibited enhanced adsorption in the presence of the cationic surfactant, CPC.