MC68HC908QT4单片机键盘模块原理及应用

本文分析了MC68HC908QT4单片机键盘模块的结构原理和寄存器功能，结合其键盘模块的特点，给出了具体的键盘应用实例。     

应用M68HC908LJ12设计单相复费率电能表

介绍了以Motorola公司的M68HC908LJ12高性能单片机为CPU的单相复费率电能表的硬、软件设计和抗干扰设计。     

The Application of Halstead's software science. Theory to Algol 68 programs

M. H. Halstead has argued that all computer programs are composed entirely of operators and operands. By counting these entities the software science theory then enables program properties such as vocabulary, length, volume, program level and language level to be calculated. For well written, or so-called ‘pure programs’, one would expect, according to the theory, good agreement between certain observed and predicted values. Also, one might expect an intuitive ordering of language levels to be confirmed by the theory, with for example, Algol 68 having a higher language level than Fortran. In this paper two different counting strategies have been applied to one implementation of the Numerical Algorithms Group (NAG) Algol 68 library. The results do not entirely match expectation.     

基于MC68HC908的系统软件更新方式的探讨

对MC68HC908系列MCU内FLASH进行更新的方式有以下2种：利用ROM驻留程序利用用户自定义的擦写程序。由于利用自定义擦写程序方式进行系统更新的方式比较灵活，且用途广泛，所以作为重点进行介绍。     

Finding irreducible components of some real transcendental varieties

An algorithm is proposed for producing all components of the varieties defined by equations which involve polynomials and exponentials of polynomials, irreducible over real algebraic numbers. The running time of the algorithm is singly exponential in the number of variables and, with this number fixed, polynomial in all other parameters of the input.     

^68Ge—^68Ga发生器的研制——^68Ge—^68Ga发生器的稳定性研究

研究了不同时间间隔淋洗６８Ｇｅ－６８Ｇａ发生器时，６８Ｇａ的淋洗曲线、淋洗效率、６８Ｇｅ的穿透率、流出液中的Ｓｎ含量及温度对６８Ｇａ淋洗效率的影响。实验结果表明，用１ｍｏｌ／ＬＨＣｌ淋洗以ＳｎＯ２为吸附剂的６８Ｇｅ－６８Ｇａ发生器，每次淋洗间隔时间１－１４天不等，历经半年时间的淋洗，６８Ｇｅ的穿透率保持在１０－７数量级，淋洗液中的Ｓｎ含量保持在４×１０－７以下。６８Ｇａ淋洗曲线的形状未发生变化，６８Ｇａ的淋洗效率为５５％—７５％，淋洗时间间隔变化不影响淋洗效率，温度对淋洗效率有较大影响。     

THE INFLUENCE OF RESIDUAL STRESS ON THE CORROSION RESISTANCE OF H68A BRASS TUBES IN SEA WATER

This paper reveals the morphological characteristics of the cracks formed in H68A brass tubes fully immersed in seawater, and studies the depth profiles of the residual stress of the tubes. Tbe great residual stress in the wall results in stress-corrosion cracking, and the unique morphology of the cracks is due to the uneven distribution of residual stress through the depth of the tube.     

Improving known solutions is hard

In this paper, we study the complexity of computing better solutions to optimization problems given other solutions. We use a model of computation suitable for this purpose, the counterexample computation model. We first prove that, if PH _P ³ , polynomial time transducers cannot compute optimal solutions for many problems, even givenn ^1– non-trivial solutions, for any >0. These results are then used to establish sharp lower bounds for several problems in the counterexample model. We extend the model by defining probabilistic counterexample computations and show that our results hold even in the presence of randomness.     

A topological characterization of random sequences

The set of random sequences is large in the sense of measure, but small in the sense of category. This is the case when we regard the set of infinite sequences over a finite alphabet as a subset of the usual Cantor space. In this note we will show that the above result depends on the topology chosen. To this end we will use a relativization of the Cantor topology, the U^δ-topology introduced by Staiger [RAIRO Inform. Théor. 21 (1987) 147-173]. This topology is also metric, but the distance between two sequences does not depend on their longest common prefix (Cantor metric), but on the number of their common prefixes in a given language U. The resulting space is complete, but not always compact. We will show how to derive a computable set U from a universal Martin-Löf test such that the set of non-random sequences is nowhere dense in the Uδ-topology. As a byproduct we obtain a topological characterization of the set of random sequences. We also show that the Law of Large Numbers, which fails with respect to the usual topology, is true for the Uδ-topology.     

Separation of Radiogallium from Zinc Using Membrane-Based Liquid-Liquid Extraction in Flow: Experimental and COSMO-RS Studies

ABSTRACT

A switch from batch to continuous manufacturing of gallium-68 (⁶⁸Ga) and ⁶⁸Ga-labeled pharmaceuticals can be advantageous, as it recycles isotopically-enriched zinc-68 (⁶⁸Zn), removes pre- and post-irradiation target manipulations, and provides scalability via dose-on-demand production. Herein we report efficient extraction of radiogallium (^66,67,68Ga = *Ga) from ZnCl₂/HCl solutions in batch and in flow using a membrane-based liquid-liquid separator. From 5.6 M ZnCl₂/3 M HCl, a 1/2 (v/v) diisopropyl ether (ⁱPr₂O)/trifluorotoluene (TFT) solvent extracts 76.3 ± 1.9% of *Ga and 1.9 ± 1.6% of Zn in flow using a single pass through. From 1 M ZnCl₂/6 M HCl, a 1/2 (v/v) n-butyl methyl ether (n-BuOMe)/TFT solvent extracts 95.7 ± 2.0% of *Ga and 0.005 ± 0.003% of Zn in flow. TFT plays a key role in controlling the interfacial tension between the aqueous and the organic phases, ensuring clean membrane-based separation. The process did not extract Cu, Mn, and Co but did extract Fe. Using HGaCl₄ and ZnCl₂ as the extractable species, the COSMO-RS theory predicts the solvation-driven extraction of Ga and Zn with a mean unsigned error of prediction of 4.0% and 3.4% respectively.