Reduction Behaviour of BOF Slags by Carbon in Iron

Experiments were carried out in a system with BOF slags from industrial operations in order to optimize the conditions of recycling BOF slags produced in the steelmaking process. Reduction reactions of FeO and P₂O₅ proceeded steadily and the FeO reduction rate was almost identical to that of P₂O₅. The reduction reaction of FeO and P₂O₅ in BOF slag at the slag/gas interface is the rate‐controlling step. The reaction rates of FeO and P₂O₅ by dissolved carbon in molten iron are of first order with respect to their respective concentrations. The reduction reactions of FeO and P₂O₅ by dissolved carbon in iron are much closer to the equilibrium state compared with the reduction by solid carbon. It is necessary to control the portion of phosphorus vaporization during reduction treatment in order to obtain efficient operational conditions for BOF slag reduction.     

On the Use of Mutation Faults in Empirical Assessments of Test Case Prioritization Techniques

Regression testing is an important activity in the software life cycle, but it can also be very expensive. To reduce the cost of regression testing, software testers may prioritize their test cases so that those which are more important, by some measure, are run earlier in the regression testing process. One potential goal of test case prioritization techniques is to increase a test suite's rate of fault detection (how quickly, in a run of its test cases, that test suite can detect faults). Previous work has shown that prioritization can improve a test suite's rate of fault detection, but the assessment of prioritization techniques has been limited primarily to hand-seeded faults, largely due to the belief that such faults are more realistic than automatically generated (mutation) faults. A recent empirical study, however, suggests that mutation faults can be representative of real faults and that the use of hand-seeded faults can be problematic for the validity of empirical results focusing on fault detection. We have therefore designed and performed two controlled experiments assessing the ability of prioritization techniques to improve the rate of fault detection of test case prioritization techniques, measured relative to mutation faults. Our results show that prioritization can be effective relative to the faults considered, and they expose ways in which that effectiveness can vary with characteristics of faults and test suites. More importantly, a comparison of our results with those collected using hand-seeded faults reveals several implications for researchers performing empirical studies of test case prioritization techniques in particular and testing techniques in general     

Prioritizing JUnit Test Cases: An Empirical Assessment and Cost-Benefits Analysis

Test case prioritization provides a way to run test cases with the highest priority earliest. Numerous empirical studies have shown that prioritization can improve a test suite's rate of fault detection, but the extent to which these results generalize is an open question because the studies have all focused on a single procedural language, C, and a few specific types of test suites. In particular, Java and the JUnit testing framework are being used extensively to build software systems in practice, and the effectiveness of prioritization techniques on Java systems tested under JUnit has not been investigated. We have therefore designed and performed a controlled experiment examining whether test case prioritization can be effective on Java programs tested under JUnit, and comparing the results to those achieved in earlier studies. Our analyses show that test case prioritization can significantly improve the rate of fault detection of JUnit test suites, but also reveal differences with respect to previous studies that can be related to the language and testing paradigm. To investigate the practical implications of these results, we present a set of cost-benefits models for test case prioritization, and show how the effectiveness differences observed can result in savings in practice, but vary substantially with the cost factors associated with particular testing processes.     

Internal pressures and thermal pressure coefficients for solid polymers

The temperature and pressure dependence of the thermal pressure coefficient and internal pressure for eight polymer solids are calculated. The principal results are as follows: (1) The pressure dependence of the thermal pressure coefficient at constant temperature is relatively small. (2) For some solid polymers, as a function of temperature, a maximum in the thermal pressure coefficient is predicted in the solid region, and the temperatures corresponding to the maximum values are estimated. (3) For most solid polymers, the zeropressure internal pressure increases with increasing temperature over the entire temperature range to the glass transition temperature or the melting point. © 1995 John Wiley & Sons, Inc.     

A randomized prospective trial comparing 45 and 90-ml oral sodium phosphate with X-Prep in the preparation of patients for colonoscopy

Incontinentia pigmenti is an uncommon genodermatosis that occurs in female infants. The characteristic dental defects are partial anodontia and the presence of some peg-shaped teeth. This report describes a patient with incontinentia pigmenti who exhibited multiple missing teeth in both arches. The patient had malpositioned teeth and decreased occlusal vertical dimension associated with the missing teeth. Orthodontic treatment was required for prosthetic purposes. The dental anomalies of incontinentia pigmenti and the treatment procedure are presented.     

Anodic oxidation ofp-t-butyltoluene in sulphuric acid solution

The electrochemical oxidation ofp-t-butyltoluene has been investigated. From several anode materials studied, Pb-Sb alloys give the best yields ofp-t-butylbenzaldehyde at 60° C in 1 M H₂SO₄.     

Spigot Algorithm and Root Computing

The word spigot indicates that the "digits" (generally in a widened meaning) of the result number are extracted successively from left to right (as if pumped through a spigot) by using only integer arithmetic, as opposed to the iterative approach, where the result number as the whole is improved after each iteration step by using (high-precision) floating-point arithmetic. The approach of spigot computing as used in papers by S. Kamal Abdaly (Comm. ACM 13(1970)), S. Rabinowitz and S. Wagon (American Mathematical Monthly 102(3) (1995)), A. H. J. Sale (Comput. J. 11(1968)) is now systematized and correctness is formally proved; the way for achieving an arbitrary accuracy is shown.Then a method for computing roots of arbitrary rational numbers is developed. If a root is not rational, spigot approach is used to compute its decimal approximation with an arbitrary given accuracy; if the root is rational, its numerator and denominator are computed exactly. This method for root computing is absolutely reliable: it is both formally proved and tested by numerical examples.     

IPTV的关键广播构建模块

电信运营商和电视运营商在为消费者提供视频内容服务上不断展开竞争。然而，与电视运营商相比，大部分电信运营商的基础设施还不具备传输高质量视频所需的带宽。因此，在内容分配上，电信运营商没有使用正交振幅调制（QAM）和MPEG2视频编码等数字调制技术，而是采用了互联网协议（IP）网络，利用MPEG4-Part10（也称为H．264-AVC）等新的编码方案来为消费者提供视频内容。     

Fully integrated CMOS limiting amplifier with offset compensation network

A fully integrated CMOS limiting amplifier (LA) is presented. Its novel implementation of the offset compensation circuit completely removes bulky off-chip RC components. The LA is designed using a 0.18 mum CMOS technology and it obtains a 40 dB gain with a bandwidth of 1.8 GHz. The total power consumption is only 18.39 mW under a 1.8 V voltage supply.