A heuristic for the label printing problem

Label printing finds many applications in industry. However, this task is still labor intensive in many printing factories. Since each template can only accommodate a fixed number of labels, an important task is to work out the compositions of templates by allocating suitable labels to each template in order to fulfill the order requirements effectively. The template design could be rather arbitrary, which usually ends up with a lot of excessive printed labels. Enhancing the template design will significantly improve the efficiency of the printing process, and, at the same time, reduce the waste of resources. This motivates the study of more automatic design methods. In this paper, the problem is first formulated as a nonlinear integer programming problem. The main variables in the formulation are the compositions and the printing frequencies of templates. For practical purpose, each type of label is confined to one template only which allows automated packing and handling. The structure of the problems is carefully analyzed and a new algorithm is proposed. Numerical results show that the proposed method is a simple but effective way of generating good template designs.     

Critical issues of wafer level chip scale package (WLCSP) withemphasis on cost analysis and solder joint reliability

Some of the critical issues of wafer level chip scale package (WLCSP) are mentioned and discussed in this investigation. Emphasis is placed on the cost analysis of WLCSP through the, important parameters such as wafer-level redistribution, wafer-bumping, and wafer-level underfilling. Useful and simple equations in terms of these parameters are also provided. Furthermore, the effects of microvia build-up layer on the solder joint reliability of WLCSP on printed circuit board (PCB) through the creep responses such as the deformation, hysteresis loops, and stress and strain are presented. Only solder-bumped with pad-redistribution WLCSPs are considered in this study     

Activation of the anti-cancer drug ifosphamide by rat liver microsomal P450 enzymes

The NADPH-dependent metabolism of ifosphamide catalyzed by rat liver microsomes was investigated in order to identify individual P450 enzymes that activate this anti-cancer drug and to ascertain their relationship to the P450 enzymes that activate the isomeric drug cyclophosphamide. Pretreatment of rats with phenobarbital or clofibrate increased by up to 8-fold the activation of both ifosphamide and cyclophosphamide catalyzed by isolated liver microsomes. Studies using P450 form-selective inhibitory antibodies demonstrated that constitutively expressed P450s belonging to subfamily 2C (forms 2C11/2C6) make significant contributions to the activation of both oxazaphosphorines in uninduced male rat liver microsomes, while the phenobarbital-inducible P450 2B1 was shown to be a major catalyst of these activations in phenobarbital-induced microsomes. Pretreatment of rats with dexamethasone increased liver microsomal activation of ifosphamide approximately 6-fold without a corresponding effect on cyclophosphamide activation rates. Ifosphamide activation catalyzed by dexamethasone-induced liver microsomes was minimally inhibited by anti-P450 2B or anti-P450 2C antibodies, but was selectively inhibited by anti-P450 3A antibodies. Selective inhibition of liver microsomal ifosphamide activation was also effected by the macrolide antibiotic triacetyloleandomycin, an inhibitor of several dexamethasone-inducible 3A P450s. These studies establish that a dexamethasone-inducible family 3A P450 can make an important contribution to rat liver microsomal ifosphamide activation, and suggest that dexamethasone pretreatment might provide a useful approach for modulation of ifosphamide metabolism in order to improve its therapeutic efficacy in cancer patients.     

Geometric criteria of hydrogen bonds in proteins and identification of `bifurcated' hydrogen bonds

Empirical criteria for identification of hydrogen bonds wereanalyzed to produce a set of geometrically consistent criteria.For a data set of 30 structures, application of a set of purelygeometrical criteria, along with exclusion of abnormal backboneconformations, also excluded a common interaction of Ser/Thrside chains with Asp/Glu side chains ([ST]/[DE] pairs). Theseinteractions were termed `bifurcated hydrogen bonds/', whichimplies delocalization of a positively charged hydrogen of hydroxylbetween the two acceptor atoms of the carboxylic group. These`bifurcated/' interactions are among the most common packingpatterns for [ST]/[DE] pairs of side chains. Therefore, theidentification of hydrogen bonds cannot be based on geometricalcriteria only and requires introduction of some physico-chemicalcriteria.     

A standardized method for CMOS unit process development

The multipurpose mask set described, which consists of three stepper reticles, contains 95% of all test structures required for CMOS process development and random defect detection, thereby dramatically reducing the stepper reticle inventory and the frequency of reticle changes. Realizing the mask set by two dozen standard unit processes minimizes the feedback loop for defect density data, parametric data and unit process data     

Ochratoxin A in pork kidneys--description of a method

A rapid procedure for the isolation and clean-up on a silica gel column is described for the determination of Ochratoxin A from pork kidneys. The detection limit is 0.3 microgram/kg.     

Tight bounds on Rician-type error probabilities and someapplications

Consider the classic problem of evaluating the probability that one Rician random variable exceeds another, possibly correlated, Rician random variable. This probability is given by Stein (1964) in terms of the Marcum's Q-function, which requires numerical integration on the computer for its evaluation. To facilitate application in many digital communication problems, we derive here tight upper and lower bounds on this probability. The bounds are motivated by a classic result in communication theory, namely, the error probability performance of binary orthogonal signaling over the Gaussian channel with unknown carrier phase. Various applications of the bounds are reported, including the evaluation of the bit error probabilities of MDPSK and MPSK with differential detection and generalized differential detection, respectively. The bounds prove to be tight in all cases. Further applications will be reported in the future     

Performance analysis of adaptive interleaving for OFDM systems

We proposed a novel interleaving technique for orthogonal frequency division multiplexing (OFDM), namely adaptive interleaving, which can break the bursty channel errors more effectively than traditional block interleaving. The technique rearranges the symbols according to instantaneous channel state information of the OFDM subcarriers so as to reduce or minimize the bit error rate (BER) of each OFDM frame. It is well suited to OFDM systems because the channel state information (CSI) values of the whole frame could be estimated at once when transmitted symbols are framed in the frequency dimension. Extensive simulations show that the proposed scheme can greatly improve the performance of the coded modulation systems utilizing block interleaving. Furthermore, we show that the adaptive interleaving out performs any other static interleaving schemes, even in the fast fading channel (with independent fading between symbols). We derived a semi-analytical bound for the BER of the adaptive interleaving scheme under correlated Rayleigh fading channels. Furthermore, we discussed the transmitter-receiver (interleaving pattern) synchronization problem