The nascent and rapidly evolving state of parallel systems often leaves parallel application developers at the mercy of inefficient, inflexible operating system software. To assess the feasibility of performance tunin...
详细信息
The nascent and rapidly evolving state of parallel systems often leaves parallel application developers at the mercy of inefficient, inflexible operating system software. To assess the feasibility of performance tuning via malleable system software and to understand the performance penalties for detailed operating system performance data capture, we describe a set of performance experiments with Choices, an experimental, object-oriented operating system designed for use with parallel systems.< >
The high variability of students' backgrounds typically found in introductory programming courses creates additional difficulties to foster motivation and ensure the desired competency and retention rates. This pa...
详细信息
ISBN:
(纸本)9781581136722
The high variability of students' backgrounds typically found in introductory programming courses creates additional difficulties to foster motivation and ensure the desired competency and retention rates. This paper presents and discusses the results of applying an assessment methodology strongly based upon lab exams (or on-computer exams) with the objective of ensuring programming pratice competency while maintaining students' motivation. It discusses the difficult balances of several assessment methods, details the used assessment methodology and finally presents students results and views. These show that lab exams, although more demanding then group assignments, can be made popular among students if they perceived them as fairer.
The deterministic simulation library SALMO-OO represents an object-oriented implementation of mass balance equations for pelagic food webs （diatoms,green algae,blue-green algae,cladocerans） and nutrient cycles （PO-...
详细信息
The deterministic simulation library SALMO-OO represents an object-oriented implementation of mass balance equations for pelagic food webs （diatoms,green algae,blue-green algae,cladocerans） and nutrient cycles （PO-P,NO-N,DO,detritus） in *** gains its structural flexibility from optional access to alternative process representations for algal growth and grazing,and zooplankton growth and *** validation of distinctive model structures determined by SALMO-OO is shown for three lake categories defined by:a)circulation types that reflect climate and morphometry,and b)
Search in repeated contexts can lead to increased search efficiency due to contextual cueing. Contextual cueing has mainly been investigated in two-dimensional displays. However, contextual cueing is affected by depth...
详细信息
Search in repeated contexts can lead to increased search efficiency due to contextual cueing. Contextual cueing has mainly been investigated in two-dimensional displays. However, contextual cueing is affected by depth information as well as by the “realism” of the search environment. To investigate these aspects further, we present a guide to design contextual cueing experiments in virtual three-dimensional environments. Specifically, we provide a general introduction to the Unity gaming engine and scripting in C#. We will focus on experimental workflows, but also cover topics like timing precision, how to process and handle participants’ input, or how to create visual assets and manipulate aspects like color. Ultimately, we will turn the entire project into a virtual reality experiment. less
作者：
LangeIBM Research
Tokyo Research Laboratory Yamato Kanagawa Japan
In his research the author is looking into the cooperation of methodology, language, and database in the design of object-oriented systems which are to be realized in an object-oriented programming language using an o...
详细信息
In his research the author is looking into the cooperation of methodology, language, and database in the design of object-oriented systems which are to be realized in an object-oriented programming language using an object-oriented database system (OODBMS). The focus is on some of the differences between traditional object-oriented design and object-oriented database design. For this purpose a small formal model of a contemporary OODBMS is built. This model describes abstractions of the most important data structures of OODBMS and their associated functionality. Based on both a pragmatic and a theoretic understanding of the architecture of contemporary OODBMSs, the author aims at presenting some of the issues to be considered in object-oriented database design such as: object management, object retrieval, and concurrency.< >
In an evolving software system, components must be able to change independently while remaining compatible with their peers. One obstacle to independent evolution is the brittle parameter problem: the ability of two c...
详细信息
ISBN:
(纸本)9781581137125
In an evolving software system, components must be able to change independently while remaining compatible with their peers. One obstacle to independent evolution is the brittle parameter problem: the ability of two components to communicate can depend on a number of inessential details of the types, structure, and/or contents of the values communicated. If these details change, then the components can no longer communicate, even if the essential parts of the message remain *** present HydroJ, an extension of Java that addresses this problem. In HydroJ, components communicate using self-describing, semi-structured messages, and programmers use pattern matching to define the handling of messages. This design stems from two central ideas: first, that self-describing messages reduce dependence on inessential message format details; and second, that object-oriented pattern matching naturally focuses on the essential information in a message and is insensitive to inessential *** have developed these ideas in the context of Rain, a distributed, heterogeneous messaging system for ubiquitous computing. To evaluate the design, we have constructed a prototype HydroJ compiler, implemented some Rain services in HydroJ, studied the evolution of an existing Rain service over time, and formalized HydroJ's key features in a core language.
Micro patterns are similar to design patterns, except that micro patterns are stand at a lower, closer to the implementation, level of abstraction. Micro patterns are also unique in that they are mechanically recogniz...
详细信息
ISBN:
(纸本)9781595930316
Micro patterns are similar to design patterns, except that micro patterns are stand at a lower, closer to the implementation, level of abstraction. Micro patterns are also unique in that they are mechanically recognizable, since each such pattern can be expressed as a formal condition on the structure of a *** paper presents a catalog of 27 micro-patterns defined on Java classes and interfaces. The catalog captures a wide spectrum of common programming practices, including a particular and (intentionally restricted) use of inheritance, immutability, data management and wrapping, restricted creation, and emulation of procedural-, modular-, and even functional- programming paradigms with objectoriented constructs. Together, the patterns present a set of prototypes after which a large portion of all Java classes and interfaces are modeled. We provide empirical indication that this portion is as high as 75%.A statistical analysis of occurrences of micro patterns in a large software corpus, spanning some 70,000 Java classes drawn from a rich set of application domains, shows, with high confidence level that the use of these patterns is not random. These results indicate consciousness and discernible design decisions, which are sustained in the software evolution. With high confidence level, we can also show that the use of these patterns is tied to the specification, or the purpose, that the software *** traceability, abundance and the statistical significance of micro pattern occurrence raise the hope of using the classification of software into these patterns for a more founded appreciation of its design and code quality.
In order to handle massively parallel systems and make them usable, an adaptive, application-oriented operating system is required. This asks for dynamically alterable system structures. A good foundation for building...
详细信息
In order to handle massively parallel systems and make them usable, an adaptive, application-oriented operating system is required. This asks for dynamically alterable system structures. A good foundation for building such structures is the family concept of parallel operating systems. Incremental loading supports the family character by extending on demand the system's active object structure and this way (possibly) switching from one family member to another. A new active object will be incrementally loaded if its invocation fails because it does not yet exist. This is noticed during object binding while using the naming services. To keep the application's code free from incremental loading aspects the naming service is made extensible. This way a family is built, namely a family of naming services. These extensions are externally definable naming strategies and exceptions.< >
In this paper, we use Kansanen's didactic triangle to structure and analyse research on the teaching and learning of programming. Students, teachers and course content are the three entities that form the corners ...
详细信息
ISBN:
(纸本)9781920682842
In this paper, we use Kansanen's didactic triangle to structure and analyse research on the teaching and learning of programming. Students, teachers and course content are the three entities that form the corners of the didactic triangle. The edges of the triangle represent the relationships between these three entities. We argue that many computing educators and computing education researchers operate from within narrow views of the didactic triangle. For example, computing educators often teach programming based on how they relate to the computer, and not how the students relate to the computer. We conclude that, while research that focuses on the corners of the didactic triangle is sometimes appropriate, there needs to be more research that focuses on the edges of the triangle, and more research that studies the entire didactic triangle.
Component-based software development has been increasingly adopted as a standard engineering practice to build large systems with prefabricated components. Although this development method enjoys the great benefits of...
详细信息
ISBN:
(纸本)0769521312
Component-based software development has been increasingly adopted as a standard engineering practice to build large systems with prefabricated components. Although this development method enjoys the great benefits of reusing valuable software assets, reducing development costs, improving productivity, etc., it also poses serious challenges to the quality assurance problem of component-based systems, since prefabricated components can not be simply trusted and they could be a new source of system failures. Solving this problem is of vital importance to safety-critical and mission-critical systems. This paper introduces a decompositional verification approach for component-based systems through both formal analysis (model-checking) and traditional software testing.
暂无评论