Drafting System Research Articles

Separating the knowledge layers: Cognitive analysis of search knowledge through hierarchical goal decompositions

AbstractHierarchical goal decompositions have proved to be a useful method to make explicit the knowledge required by users to perform tasks in a wide range of applications such as computer‐aided drafting (CAD) systems. This analysis method progressively decomposes a given task starting from the task layer on the top of the decomposition, to the keystroke layer at the bottom. The analysis enables a close inspection of the knowledge required to perform the task at each layer of the decomposition. In this paper we show how the method of hierarchical goal decomposition can be used to understand more precisely the knowledge that is required to perform information search tasks. The analysis pinpoints: (1) the critical strategies in the intermediate layers of knowledge that are known by experts searchers; (2) why such knowledge is difficult to acquire by novice searchers; (3) how the analysis provides testable predictions of behavior based on the acquisition of different types of knowledge. We conclude by discussing the advantages provided by hierarchical goal decompositions, and how such an approach can lead to the design of systems and training.

Effects of Pin Drafting on Irregularities of Sliver Made from Fine Denier Fibers

To improve the quality of spun yarn made from fine denier fibers, the technique of pin drafting is examined and discussed. Slivers made from four levels of fiber fineness are drafted with an experimental pin drafting system by changing the draft ratio. Deviations between indices of irregularities I corresponding to output and input slivers are calculated to evaluate the performance of the drafting process. Deviations of the gill sliver decrease with decreasing fiber denier. This phenomenon can be explained by the larger number of fibers contacting the pins of the gill fallers and the greater interfiber cohesive force with decreasing fiber denier. Irregularities of sliver from fine denier fibers are effectively negated by an appropriate pin drafting system.

An object-oriented intelligent CAD system for ceramic kiln

Abstract This paper describes an integrated intelligent computer-aided design (CAD) system for the ceramic kiln, with an object-oriented database as its core, utilizing object-oriented approach. In addition to the structure and methods of the object-oriented database, the knowledge-based system and the drafting system are discussed. The idea of an integrated intelligent CAD environment is introduced, which can greatly improve design efficiency and quality.

Legislative Technique as Basis of a Legislative Drafting System

This contribution reports ongoing research concerning a legislative drafting system named SOLON.1 The system was developed at the Institute of Social Law, Katholieke Universiteit Leuven, Belgium. SOLON is designed to support the implementation of the basic principles of legislative technique and is specifically based on the translation into computer algorithms of the 254 drafting guidelines of the Flemish government. First, specific attention will be paid to the Flemish guidelines, second, the features and particular functions of the system will be discussed.

Development of three‐dimensional apparel CAD system

A comprehensive apparel CAD system was developed to perform automatic garment pattern drafting and the prediction of the final drape shape of designed garment putting on the human body. Three dimensional apparel CAD system starts with a flat garment pattern drafting system. A computerized pattern design script language has been created based on the traditional patterner’s principles to develop an automatic draft system of performing basic garment pattern drafting as well as grading rule generation. A pattern modification system was also developed considering functions required in apparel CAD such as auxiliary pattern generation, seam line creation, and dart manipulation to generate engineering patterns which can be used in the three dimensional garment shape prediction system presented later in part II of this paper.

Developing a New Drafting System for Ring Spinning Machines

In order to raise yam quality, a new drafting system concept for ring spinning machines is developed in this study, along with an analysis of its controlling effects. To optimize the new drafting system, its structural parameters are studied and two empirical equations for yarn unevenness and nep count model its design. The equation of yam unevenness is used to find the optimum structural parameters of the new drafting system. Practical spinning tests with the optimized system prove that it can reduce unevenness, thin places, thick places, and neps in spun yarns, and that the equation for yarn unevenness can be used to satisfactorily estimate the unevenness of spun yams.

Mohair Fibre Drafting in Ring Spinning Part II: Pinned Roller

This paper reports a novel modification to the drafting system of conventional ring spinning. The modification entails the use of a pinned middle bottom roller, together with the conventional double aprons for fibre drafting. The additional pins on the middle bottom roller are intended to improve fibre opening and alignment during fibre drafting. The pinned roller features a combing action coupled with fibre control due to fibre/pin interaction, which is thought to be particularly important for slippery fibres such as mohair. Both mohair and wool yarns were spun with the modified drafting arrangement. The yarn assessment results obtained indicate significant improvement in yarn evenness and imperfections. Yarn hairiness and tensile properties were also improved.

Bacteriological Evaluation of Composting Systems in Sludge Treatment

Sludge disposal was considered as a serious problem to the authorities. Thus, the treatment of sludge resulting from sewage treatment plants to remove pathogenic microorganisms and to improve its impact on the environment was considered as the main objective of several investigators. Composting is one of the methods of sludge treatment. Different systems of composting (static pile, windrow and natural draft) were applied and evaluated bacteriologically. Faecal coliform and salmonellae were removed completely during the first two weeks in case of forced aeration, but the former are still present till near the end of experiment with natural aeration. For the natural draft system with sawdust base, faecal coliform reduction increased up to 100% after 7 weeks, while faecal streptococci and coliphage decreased gradually and were removed completely at the end of treatment. Salmonellae disappeared after a few days from starting treatment. In case of alkaloids addition (cement and lime), the tested organisms reached acceptable levels with any concentration of alkaloids. Coliphage and faecal streptococci survived till the end of treatment. So, from the previous results it is clear to say, coliphage and faecal streptococci were more resistant to the composting processes than other organisms.

Improvements in the cross‐sectional structure of composite yarn†

This study investigated composite yarn on a 4‐roller drafting system with the goal of improving the cross‐sectional structure of polyester filament/rayon fiber (P/R) composite yarn. We found that a 4‐roller drafting system with 2 double aprons is beneficial for controlling the filament spread width, as well as improving the mixing efficiency of spreaded polyester filaments and drafted rayon fibers in the nip of the front roller. Consequently, this arrangement will yield a composite yarn with better blend uniformity. The results revealed that the fraction of the uniform distribution type and the wrapping type could increase up to 34.0% and 19.5% respectively.

The Administrative Systems of the Nanzhao and Dali Kingdoms

This article examines geographical arrangement and its changes via the administrative systems established by the Nanzhao _??__??_ and Dali _??__??_ kingdoms in Yunnan, with a view to shedding the new light upon the character and extent of rules excercised by those kingdoms.To begin with, the Nanzhao kingdom had several jian _??_ as provinces in the central area. These jian were mainly established on the west coast of Lake Erhai _??__??_ and the river basins in the south of the Lake, where the royal Meng family _??__??_ and most of the ruling class families had their strongholds. The differences between the jian in appearing Man-shu _??__??_ and that in Xin-tang-shu _??__??__??__??__??__??_ reflect the dates of the original sources. Although some scholars say the word tan_??_, instead of jian, should be used as the name of the resulting system, the difference in usage of two words tells us that tan is a kind of common suffix for a river basin, not a homophone of jian as a province.Secondly, on the periphery were jiedu _??__??_ and dudu _??__??_. The difference between jiedu and dudu is not so clear, but it should be pointed out that the directors of jiedu were Da-jun-jiang _??__??__??_, a title second in rank only to the prime ministers, Qing-ping-guan _??__??__??_ Regarding dudu, the sources say that the kingdom established a dudu for every ten thousand households, which is thought to be a kind of military draft system, such as Fubing-zhi _??__??__??_ in Tang China. The scale of military power, must also have something to do with jiedu and dudu as administrative institutions. On the other hand, jiedu and dudu were established on the major trade routes from the Erhai area to the four quarters. Especially from east to west, on the line around lat. 25°N, there are located many of the major river basins in Yunnan. It can be said that these trade routes formed a skeleton of the Nanzhao kingdom, with the river basins as their joints.Under the Dali kingdom, jiedu and dudu were reconstructed as fu _??_. And some jian, began to be established around those fu. Those jian were settled by immigrants from the Erhai area, who brought administrative systems familiar to them. The directorships of fu and jian gradually came to be transmitted by inheritance, and they often rebelled against the power of the kingdom, which shows that fu had begun to operate autonomously. The time when fu and jian were established in the periphery was also the time when the Bai people _??__??_ and their culture was formed in the Erhai area. Immigrants diffused their culture to those areas leading to a condition for the rapid acceptance of the Han culture that would arrive in the next age.

An integrated intelligent system for ceramic kilns

This paper describes an integrated intelligent computer-aided design (CAD) system for ceramic kiln with an object-oriented database as its core utilizing object-oriented programming (OOP) technology. In addition to the structure and methods of the object-oriented database, the expert system and the drafting system are discussed in detail. The idea of an integrated intelligent CAD environment is introduced which can greatly improve design efficiency and quality.

Bacteriological evaluation of composting systems in sludge treatment

Sludge disposal was considered as a serious problem to the authorities. Thus, the treatment of sludge resulting from sewage treatment plants to remove pathogenic microorganisms and to improve its impact on the environment was considered as the main objective of several investigators. Composting is one of the methods of sludge treatment. Different systems of composting (static pile, windrow and natural draft) were applied and evaluated bacteriologically. Faecal coliform and salmonellae were removed completely during the first two weeks in case of forced aeration, but the former are still present till near the end of experiment with natural aeration. For the natural draft system with sawdust base, faecal coliform reduction increased up to 100% after 7 weeks, while faecal streptococci and coliphage decreased gradually and were removed completely at the end of treatment. Salmonellae disappeared after a few days from starting treatment. In case of alkaloids addition (cement and lime), the tested organisms reached acceptable levels with any concentration of alkaloids. Coliphage and faecal streptococci survived till the end of treatment. So, from the previous results it is clear to say, coliphage and faecal streptococci were more resistant to the composting processes than other organisms.

Factors Influencing the Processing of Flax Fibres: Gill-box Friction

The friction between technical flax fibres and the gill box, the most widely applied element controlling the movement of bast fibres in the drafting zone, is investigated. By regression and multiple-correlation analysis, a mathematical model for the estimation of the coefficient of friction between technical flax fibres and the gill box is obtained from the experimental data. Knowledge of the friction permits correlation of the linear density of the sliver supplied in the drafting system with both the drawing forces and the velocity of the fibres.

Evaluation of compacted urea fertilizers prepared with acid and non-acid producing chemical additives in three soils varying in pH and cation exchange capacity; II. Yield and N use efficiency by rice

With a view to evaluate the effect of different chemical additives on the efficacy of urea, a green house study was conducted with wet season rice (Oryza sativa L.) as test crop. The results showed that compaction of phosphogypsum (PG), diammonium phosphate (DAP), ZnSO4, NH4Cl or KCl with urea increased the rice yield and N use efficiency as compared to that obtained with straight urea. A significant positive correlation between potential N loss (measured by soluble N in floodwater) and NH3 volatilization (measured by forced air draft system) was observed. The results clearly indicate that N use efficiency can be increased through suitable modification of urea by compacting it with acid and non-acid producing fertilizers such as NH4Cl, KCl, ZnSO4 and DAP or industrial byproduct like phosphogypsum.

Mismatched metaphor: user vs system moeel in computer-aided drafting

We report findings from an extensive study of the users of a Computer-Aided Drafting (CAD) system. Our observations suggest that the CAD system is used inefficiently, because users approach computer-aided drafting from a T-square metaphor reflecting their past experience with traditional drawing media. This prevents them from discovering and using effectively powerful system commands that have no equivalent in manual techniques. These findings suggest that we should rethink the ways in which CAD users are trained and manuals are written, and that we introduce CAD users to a more strategic use of CAD, particularly to a Detail/Aggregate/Manipulate (DAM) strategy that takes advantage of the compositional logic underlying a design.

High Tech Impellers Offer Efficiency Gains for Cement Plant

ABSTRACT This article describes the Performance Optimization Study of a cement kiln induced draft system and subsequent installation of high efficiency fan impellers. Three problematic areas are addressed: low fan efficiency, aerodynamically caused vibrations, and high fan starting time.

Refining the use of evaporation in an experimental down-draft cool tower

Direct evaporative cooling has long been recognized as an energy-efficient and cost-effective means for space conditioning in hot dry areas. In order to extend the use of evaporative cooling to include exterior or semi-enclosed spaces, a down-draft evaporative ‘cool tower’ was integrated in the project of a 500 m 2 glazed courtyard located at the heart of a building complex in the arid Negev Highlands of southern Israel, designed by the authors. The present article describes the development of the cooling tower system, undertaken in three phases: (i) Prototype analysis. Performance of a small-scale tower was monitored, and comparisons were drawn between varying rates and mechanisms of water and air supply. The results indicated a potential for substantial temperature reduction in the order of 10 °C under summer daytime conditions, but a meager cooling output when using a natural draft system. Mechanical-forced air flow was thus utilized in the actual tower. (ii) Field monitoring. The cool tower, approximately 10 m in height and 10 m 2 in cross-sectional area, was operated and monitored during a summer season; its performance was analyzed using a series of water supply mechanisms and operating modes. The system produced a peak cooling output of just over 100 kW, with a wet bulb temperature depression of close to 85–95% during all hours of operation, and a water consumption rate of approximately 1–2 m 3/day. (iii) Refinement. Potential improvement in the system's operation was investigated through the development of a wind capture mechanism for increasing inlet pressure and air flow to the space. Both fixed and dynamic capture units were investigated, with wind speed and direction as well as internal air speeds measured in the small-scale prototype tower. The wind capture unit with the simplest configuration and best performance is recommended for future integration in the full-scale tower.

Qualitative Geometric Reasoner for Integrated Design

The widespread use of computer-aided drafting (CAD) systems within the engineering domain has provided significant advances in the capability to model design solutions. However, the focus of these systems on detailed design solutions has resulted in a corresponding lack of automated design assistants for the generation of conceptual design solutions, the primary reason being the incompatibility between the emphasis on geometric coordinates in detailed design and the emphasis on qualitative definitions in conceptual design. This paper presents one approach to bridging this representation gap, through the use of a qualitative geometric reasoner for integrated design (GRID). The paper presents a prototype GRID system that uses artificial intelligence representation and reasoning techniques to interpret CAD models and respond to qualitative geometric queries from automated design assistants within an integrated design environment. The expansion of qualitative geometric reasoning beyond spatial reasoning to in...

設計および製造の統合をめざした作図システムの構築 : PC住宅生産におけるCAD/CAM/FAシステムの経営工学的調査研究(その1)

This paper describes CAD/CAM/FA System for PC middle-rise apartment. In this Part 1, the Author reports on the results of research for building up a drafting system by making use of CAD that makes design drawings of PC houses and PC panels efficiently and unmistakably. Unifying the expression form in the drawings and rearranging the design drawing process sequence, diagram data created in the preceding process were able to be used in the succeeding process. Thus, highly efficient drafting system was realized.

Evaluating GIS for Establishing and Monitoring Environmental Conditions of Oil Fields: ABSTRACT

Good management of an oil field and compliance with ever-increasing environmental regulations is enhanced by technologies that improve a company`s understanding of field/production facilities and environmental conditions that have occurred to both through time. In Nigeria, Kazakhstan, Indonesia, and offshore Cabinda, remote sensing, computer-aided drafting (CAD) and Global Positioning System (GPF) technologies have effectively been used by Chevron to provide accurate maps of facilities and to better understand environmental conditions. Together these proven technologies have provided a solid and cost-effective base for planning field operation, verifying well and seismic locations, and locating sampling sites. The end product of these technologies is often locations, and locating sampling sites. The end product of these technologies is often cartographic-quality hardcopy images and maps for use in the office and field. Chevron has been evaluating the capability of Geographical Information System (GIS) technology to integrate images, maps, and tabular data into a useful database that can help managers and workers better evaluate conditions in an oil field, plan new facilities, and monitor/predict trends (for example, of air emissions, groundwater, soil chemistry, subsidence, etc.). Remote sensing, CAD (if formatted properly), and GPS data can be integrated to establish the spatial or cartographic base of themore » GIS. A major obstacle to establishing a sophisticated GIS for an overseas operation is the initial cost of data collection and conversion from legacy data base management systems and hardcopy to appropriate digital format. However, Chevron routinely uses GIS for oil spill modeling and is now using GIS in the field for integrating GPS data with field observations and programs.« less