IGES Model Comparison System: A Tool for Tsting and Validating IGES Processors

The IGES Model Comparison System (IMCOS) is the first test tool to allow an easy and automatic semantic comparison of CAD models represented in IGES format. By systematically analyzing and comparing entity data and structures of generated and exchanged IGES models, it detects loss of information and functionality resulting from model exchange via IGES processors. IMCOS was designed and implemented as a tabledriven IGES processor to allow external control of the comparison process and full coverage of the current version of IGES (Version 3.0) and future versions. This article presents the basic concepts of IMCOS. The great interest in and discussion of IMCOS have shown the importance of such a test tool. IMCOS may be used as one of several test tools within an overall IGES verification program.     

Wheat wet fractionation processes

In this review the wet fractionation of wheat into major components has been described. At first early whole wheat processes - the Halle fermentation and the Alsation method - have been outlined. Then the following new processes have been discussed: Corn wet milling type process, Pillsbury hydro process, Far-Mar-Co-process and Screening process. At last wet fraction processes of flour (Martin, Batter, Alkali, Fesca, Alfa-Laval/Raisio) will be considered.     

Oxidation and mineralisation of substituted phenols by Fenton's reagent and catalytic wet oxidation.

Catalytic abatement of solutions of 1,000 mg/L in phenol, ortho and para nitrophenol and ortho and para cresols was acomplished by using two catalytic systems. Fenton's reagent was used at 50 degrees C by adding 10 mg/L of ferrous cation and different dosages of H2O2. The mixture was reacting isothermically in a batch way during 3 hours. Catalytic wet oxidation (CWO) was carried out by using a commercial Activated Carbon, Industrial React FE01606A, CWO runs were carried out in a fixed bed reactor (FBR) with concurrent upflow. Temperature and oxygen pressure of the reactor were set to 160 degrees C and 16 bar, respectively. While phenols are quicky oxidised by the Fenton reagent higher mineralisation was obtained in the CWO process.     

Possibility of sewage and combined sewer overflow reuse with biological aerated filters.

The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions.     

Concurrent Cholesky factorization of positive definite banded Hermitian-matrices

First the Cholesky factorization is extended to cover uniformly partitioned banded positive definite matrices of rank n which may be real symmetric or Hermitian. Then two stratagems are given for the use of the algorithm in concurrent machines where the number of processing elements is less than required to factor the matrix in as few serial steps as possible, and where uniformly high efficiency is expected from all processing elements. Expressions are given for the efficiency factor e appearing in the speed-up expression g = eN, and these are specialized for the N node hypercube machine as a function of partition size s, the number N of processing elements of the hypercube machine, and the cost μ of interelement transmission relative to computation. It is shown that efficiency factor e is inversely proportional to μ/s, and that e is almost independent of N when N is large and μ/s = 0. The task is completed in n/s serial steps with no limit on n. The half bandwidth b of the matrix is 2Ns.