Showing papers by "Hong Kong Polytechnic University published in 1989"
01 Jan 1989
TL;DR: Yang et al. as discussed by the authors presented a model for three-dimensional Fabrics for Composites, including two-dimensional Fabric Composites and flexible and triaxial Woven Fabrics.
Abstract: 1. An Introduction to Textile Structures and Their Behaviour (F. Scardino). 2. Mechanics of Yarn and Nonwoven Fabrics (J.W.S. Hearle). 3. Nonlinear Mechanics of Woven and Knitted Materials (S. Kawabata). 4. Triaxially Braided Materials for Composites (J. Skelton). 5. Three-dimensional Fabrics for Composites (F. Ko). 6. Strength and Failure of Woven Carbon-fibre-reinforced Plastics for High Performance Applications (S.M. Bishop). 7. Analysis and Modelling of Two-dimensional Fabric Composites (T.W. Chou, T. Ishikawa). 8. Thermo-elastic Analysis of Triaxial Woven Fabric Composites (J.-M. Yang, T.-W. Chou). 9. Flexible Composites (T. Akasaka). 10. Elastic and Inelastic Response of Coated Fabrics to Arbitrary Loading Paths (N. Stubbs). 11. Design of Fabric Reinforced Composites (S.R. Moghe). Author Index. Subject Index.
346 citations
TL;DR: In this paper, the average coefficient for heat transfer from a finned surface to the ambient environment, for all the finned surfaces in these two types of configuration, was assessed.
81 citations
TL;DR: In this paper, the authors examined the revaluation of shares surrounding the cancellation of mergers over the years 1976-1985, and classified the market reaction for failed mergers by the terminating party, as in Dodd (1980), and examined the returns for the effects of subsequent merger activity similar to the way that Bradley, Desai and Kim (1983) investigated canceled tender offers.
Abstract: This study examines the revaluation of shares surrounding the cancellation of mergers over the years 1976-1985. The results are first categorized according to the party cancelling the merger and then by subsequent merger activity. The results are as expected: target firms that become involved in merger activity, subsequent to the cancellation, experience positive cumulative prediction errors (CPEs). Targets that do not become involved in subsequent merger activity have CPEs that return to pre-merger announcement levels. These results do not vary when bidders or targets cancel the merger. DODD (1980) FINDS THAT, WHEN a merger is terminated by the target, target firm cumulative abnormal returns remain positive and above pre-merger announcement levels. When bidder firms cancel, target firm prices revert to preoffer levels. Dodd concludes that for target-canceled mergers there is "a permanent revaluation of the target shares" (p. 137). Bradley (1980) and Dodd and Ruback (1977) show that the market price of target shares does not return to pre-offer levels for canceled tender offers. Bradley, Desai, and Kim (1983) demonstrate that this is because shareholders anticipate a subsequent tender offer. We classify market reaction for failed mergers by the terminating party, as in Dodd (1980). We then examine the returns for the effects of subsequent merger activity similar to the way that Bradley, Desai, and Kim (1983) investigated canceled tender offers. Our results show that the "revaluation" that Dodd (1980) found disappears when target firms are not involved in subsequent mergers but does persist for targets involved in subsequent mergers regardless of who cancels the first merger. When mergers are canceled by parties other than the bidder or target firm, we find that there is no permanent share revaluation because, for these firms, there are no subsequent mergers.
63 citations
TL;DR: In this article, the authors measured the steady state rates of heat dissipation under natural-convective conditions, from heat exchangers with vertical rectangular fins attached to a rectangular base, with a length of 150 mm and a protrusion of either 10 or 17 mm.
39 citations
TL;DR: In this paper, the authors describe the tourism development process employed by an economically depressed rural coal mining county in the state of Virginia, USA, which initiated its tourism development through a situation analysis, which involved such research techniques as a focus group study, content analysis and visitor surveys.
20 citations
TL;DR: In this paper, the authors measured the steady state rates of heat dissipation from an array of stainless-steel, vertical rectangular fin arrays under natural-convection conditions, when their base (which was either vertical or horizontal) was maintained at a uniform temperature of 20 or 40 K above that of the ambient environment.
14 citations
TL;DR: In this article, the fire risk of hotels in Hong Kong was studied by carrying out a survey on the fireload, local design consideration and past records, and it seems that the present design provides adequate safety and ability to control accidents as illustrated from past cases.
12 citations
TL;DR: In this paper, a mathematical model was developed to simulate the dispersion of carbon monoxide from a vehicular tunnel with the exit located near a hill under the action of wind.
10 citations
Journal Article•
TL;DR: In this article, the optimal design of a finned heat-exchanger, so that it exhibits the maximum steady-state rate of heat transfer performance in atmospheric air, has been identified.
Abstract: The values of the geometric parameters corresponding to the optimal design of a finned heat-exchanger, so that it exhibits the maximum steady-state rate of heat-transfer performance in atmospheric air, have been identified. The most influential parameter is the separation between the parallel vertical fins. For heat-exchanger base temperatures at up to 40 K above that of the ambient environment, the value of this optimal separation is approximately 10 mm. The corresponding approximate optimal values of the Duralumin fins' thickness and length are 2 mm and 250 mm respectively. (Author)
10 citations
TL;DR: In this paper, a computerized energy management system is used to control the steam supply in a dairy-products firm: prior to its introduction and use, more than 58% of the steam generated was wasted.
8 citations
TL;DR: In this article, three observers each judged differences between pairs of 25 colors in each of 12 intersecting oblique planes in the color space of the uniform color scales of the Optical Society of America (OSA).
Abstract: Three observers each judged differences between pairs of 25 colors in each of 12 intersecting oblique planes in the color space of the uniform color scales of the Optical Society of America (OSA). For each set of 25 colors, a three-dimensional configuration of points was determined for each observer, by use of the KYST algorithm. Equal judgments of differences between pairs of the colors are, as nearly as possible, represented in the configurations by equal distances between the points that represent the colors, and greater judgments by greater distances. The rms relative standard deviations of the judgments ranged from 0.061 to 0.214. The stress, as determined by the KYST algorithm, ranged from 0.048 to 0.151. In the configurations, the surfaces that correspond to the oblique planes in OSA color space are curved significantly.
TL;DR: In this article, the authors performed simple experiments to elucidate the action at the chisel edge in spade drilling and showed that with drill point angles in the range 80-140°, chip formation occurs over the whole of the chisel edge width in the presence of stable dead metal zones (built-up edges) which form on the leading halves of the faces bounding to the chaisel edge.
Abstract: Some simple experiments performed to elucidate the action at the chisel edge in spade drilling are described. These show that with drill point angles in the range 80–140°, chip formation occurs over the whole of the chisel edge width in the presence of stable dead metal zones (built-up edges) which form on the leading halves of the faces bounding to the chisel edge. Expressions for the torque and thrust force appropriate to removal at the drill lips are modified to reflect conditions at the chisel edge and the resulting expressions are shown to describe the dependence of the torque and the thrust on feed rate quite well. Experiments extended to include a 160° point angle drill revealed different behaviour in that the built-up edges were unstable and chip formation at the chisel edge was cyclic. Finally, the torque and thrust originating at the margins of the drill are quoted, but no explanation on the mechanism by which they are generated is offered.
TL;DR: In this article, the authors measured chip flow angle and chip length ratios along with calculations of the change of rake angle along the lips of spade drill heads and found that removal by the lips in spade drilling is quasi-orthogonal.
Abstract: Measurements of the chip flow angle and of the chip length ratios (which afford estimates of the normal shear plane angle) along with calculations of the change of rake angle along the lips of spade drills reveal that removal by the lips in spade drilling is quasi-orthogonal. This, coupled with the realisation that for spade drills (where the drill diameter is large compared to the chisel edge length), the assumption that the lips pass through the centre of the chisel edge introduces no serious error, enables simple expressions for the torque and thrust force originating at the lips to be obtained. For spade drills without chip breaker slots, these expressions are found to give an accurate description of the torque and thrust when feed, point angle and the inner and outer diameter of tubular workpieces are varied. These expressions are subsequently modified to allow for the influence of chip breaker slots.
TL;DR: In this paper, the authors investigated the role of transport pricing in network design and described two facts about flow pattern in a transportation system, illustrated by an example of Braess paradox, is that adding a new link to the network does not necessarily minimize the total travel time.
Abstract: This paper investigates the role of transport pricing in network design and describes two facts about flow pattern in a transportation system. The first, illustrated by an example of Braess paradox, is that adding a new link to the network does not necessarily minimize the total travel time. The second is that introduction of appropriate toll pricing may reduce not only the total network time but also the travel time for each individual traveller. It follows with the investigations of different system objectives and different pricing policies (only toll pricing and distance-based pricing are considered), and shows how they affect the system performance and flow pattern. Lastly, a systematic optimization process is proposed for integrated planning of transport network and pricing policies.
01 Jul 1989
TL;DR: The entire system was monitored and controlled by a PC which acted as the programmable DDC controller and the role of the ADDA interface was to convert the analog signal received from the temperature-sensing circuit and power transducer into digital signals to the actuator.
Abstract: As shown in Figure 1, the entire system was monitored and controlled by a PC which acted as the programmable DDC controller. The role of the ADDA interface was to convert the analog signal received from the temperature-sensing circuit and power transducer into digital signals and to convert the digital control action signal from the digital computer into analog form to the actuator. The commanding software was written in BASIC Language which was capable of receiving and evaluating the instantaneous air duct temperature and power consumption of the heater. The error and the corresponding PID control action was then computed and the appropriate control voltage output applied to the actuator which was coup-