Producing robust use case diagrams via reverse engineering of use case descriptions

In a use case driven development process, a use case model is utilized by a development team to construct an object-oriented software system. The large degree of informality in use case models, coupled with the fact that use case models directly affect the quality of all aspects of the development process, is a very dangerous combination. Naturally, informal use case models are prone to contain problems, which lead to the injection of defects at a very early stage in the development cycle. In this paper, we propose a structure that will aid the detection and elimination of potential defects caused by inconsistencies present in use case models. The structure contains a small set of formal constructs that will allow use case models to be machine readable while retaining their readability by retaining a large degree of unstructured natural language. In this paper we also propose a process which utilizes the structured use cases to systematically generate their corresponding use case diagrams and vice versa. Finally a tool provides support for the new structure and the new process. To demonstrate the feasibility of this approach, a simple study is conducted using a mock online hockey store system.     

Antioxidant and free radical-scavenging activities of smooth hound (Mustelus mustelus) muscle protein hydrolysates obtained by gastrointestinal proteases

We have investigated the antioxidative activity of five hydrolysates from smooth hound (Mustelus mustelus) meat obtained by various gastrointestinal proteases: crude enzyme extract, low molecular weight (LMW) alkaline protease and trypsin-like protease from M. mustelus intestine, pepsin from M. mustelus stomach, and bovine trypsin.     

Numerical study of compact shear (Mode II) type test specimen geometry

The Iosipescu shear test specimen geometry has been investigated by a number of research workers in recent years with conflicting results. The paper describes a numerical study of a compact shear test specimen, based on the Iosipescu geometry, which is proposed to investigate size effects in shear failure. A range of geometries has been studied and the extreme cases are reported. Results are presented for the largest absolute principal stresses together with a detailed study of the stresses between and around the roots of the two notches introduced in the test specimens. The results for the largest absolute principal stresses show that tensile stresses are created at the roots of the two notches. These tensile stresses may result in Mode I failure and probably account for the Mode I or mixed mode fracture observed in tests using the Iosipescu geometry. The results for the distribution of stresses between the roots of the two notches show that deep notches increase the likelihood of shear fracture prior to tensile failure. Shallow notches give a stress distribution similar to that developed in the indirect tensile test and hence tensile failure is likely to precede shear failure in such cases. Further numerical and experimental work is proposed.      

Effects on Phase Transitions in Tripalmitin due to the Presence of Dipalmitin,Sorbitan-Monopalmitate or Sorbitan-Tripalmitate

The effects of diglycerides, sorbitan-monoesters and sorbitan-triesters on triglyceride polymorphic transitions have been examined. Earlier reported effects of retardation of β' ← transitions due to the presence of asymmetric diglycerides were found to be the same from the racemic and antipode forms. The α ← β and β' ← β transitions of tripalmitin (PPP) were followed when sorbitan-monopalmitate (SMP), sorbitan-tripalmitate (STP), or dipalmitate (DP) were present. The STP gave a slightly stronger reduction in transition kinetics than DP, whereas SMP was found to promote the transition. In order to understand the mechanisms involved the binary systems SMP-PPP and STP-PPP were examined. In the case of SMP-PPP a 1:1 molecular compound is formed, whereas STP-PPP a 1:1 molecular compound is formed, whereas STP-PPP shows a simple eutectic behaviour.     

Metabolic fate of gossypol: the metabolism of14C-gossypol in rats

Balance studies designed to obtain information concerning the metabolic fate of gossypol in rats were carried out utilizing two groups of animals. One was fed a basal diet and the other the same diet plus 500 ppm of iron as FeSO₄. Single doses of 5 mg each of¹⁴C-labeled gossypol (spec. act. 19.8 μCi/mmole) were administered. The animals were maintained in metabolic cages and killed after various periods of time. The data indicate that gossypol was poorly absorbed from the gastrointestinal tract and rapidly eliminated from the animal body. Although the main route for gossypol elimination from the animal was by fecal excretion in both treatments, the percentage of the total activity eliminated via the feces varied and depended on the level of iron supplied in the diet. The results demonstrate that gossypol was least excreted via urine and that urinary excretion of radioactivity was diminished by iron supplementation to the diet. Most of the radioactivity retained was found in the contents of different parts of the gastrointestinal tract. Tissues, the liver, muscle, kidney and blood had the highest radioactivity, with the liver having the highest specific activity. The data also demonstrate that addition of iron to the ration diminishes¹⁴C radioactivity in the animal body. This effect might be attributed to the formation of chelates that could not be absorbed through the small intestine. Catalysis of the decarbonylation of gossypol by iron also appears to be a factor. Deceased March 9, 1969.     

用于硬质聚氯乙烯的有机热稳定剂——巴比土酸和硫代巴比土酸

在空气中180℃的条件下，研究了用作硬质聚氯乙烯（PVC）热稳定剂的巴比土酸（BA）和硫代巴比土酸（TBA）。这些化合物作为热稳定剂的效率，可以通过测定诱导期（Ts）的长短来评价，其间，无可检量的氯化氢气体能够被发现；还可以通过连续电势滴定法，一方面测定脱氯化氢的速率，另一方面测定降解聚合物的色变程度来评价。其稳定效率与二碱式碳酸铅（DBLC）、二碱式硬脂酸铅（DBLS）、硬脂酸钡-镉-锌（硬脂酸Ba—Cd—Zn）、正丁基锡硫醇盐（n—OTM）和马来酸二丁基锡（DBTM）进行了比较。除DBTM参比稳定剂表现出和BA及TBA差不多的稳定效率之外，所研究的有机稳定剂比所有其他参比稳定剂显示出了更高的效率。此外，它们还赋予了降解样品较好的色稳定性，本文还提出了稳定剂作用的自由基机理。稳定效率被认为是由于稳定剂的相对更稳定部分置换了PVC链上的不稳定氯原子所造成的。这也破坏了造成色变的主要因素，共轭双键的形成。     

Role of microstructure and residual stresses on fatigue crack initiation of carbonitrided steels

In this paper the role of microstructure and residual stresses on fatigue crack initiation of gaseous carbonitrided steels is examined. Optimum for austenite content in the case is investigated for microstructures containing bainite and for those without bainite. Fractographic study suggests subsurface initiation sites for notched specimens when austenite content is high and initiation sites at the surface when austenite is low.