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The understanding of how the sediment deposit thickness influences the incipient motion characteristic is still lacking in the literature. Hence, the current study aims to determine the effect of sediment deposition thickness on the critical velocity for incipient motion. An incipient motion experiment was conducted in a rigid boundary rectangular flume of 0.6 m width with varying sediment deposition thickness. Findings from the experiment revealed that the densimetric Froude number has a logarithmic relationship with both the thickness ratios ts=d and ts=y0 (ts: sediment deposit thickness; d: grain size; y0: normal flow depth). Multiple linear regression analysis was performed using the data from the current study to develop a new critical velocity equation by incorporating thickness ratios into the equation. The new equation can be used to predict critical velocity for incipient motion for both loose and rigid boundary conditions. The new critical velocity equation is an attempt toward unifying the equations for both rigid and loose boundary conditions. [ABSTRACT FROM AUTHOR]

This paper highlights a preliminary study on the potential of a tipping flush gate to be used in an open storm drain to remove sediment. The investigation was carried out by using a plasboard model of the tipping flush gate installed in a rectangular flume. A steady flow experiment was carried out to determine the discharge coefficients and also the outflow relationship of the tipping flush gate. The velocity produced by the gate at various distances downstream of the gate during flushing operation was measured using a flowmeter and the velocity at all the points was higher than the recommended self-cleansing design available in the literature. A preliminary experiment on the efficiency of flushing was conducted using uniform sediment with d50 sizes of 0.81, 1.53 and 4.78 mm. Results generally showed that the number of flushes required to totally remove the sediment from the initial position by a distance of 1 m increased by an average of 1.50 times as the sediment deposit bed thickness doubled. An equation relating the number of flushes required to totally remove the sediment bed for 1 m with the sediment bed deposit thickness was also developed for the current study. [ABSTRACT FROM AUTHOR]

The results of tests on six micro-concrete wide beam ribbed slabs at edge column locations are presented. It was found that punching shear failure of a wide beam ribbed slab can occur at an edge column. Although a punching shear failure of a wide beam ribbed slab is very similar to that of a solid slab, the shear capacity is reduced relatively, because some of the potential shear failure surface is lost when it enters the ribbed section. A plastic theory for punching shear was developed, which gave good agreement with the test failure loads. [ABSTRACT FROM AUTHOR]

The results are presented of tests on 20 micro-concrete wide beam ribbed slabs at internal column locations. It was found that shear failure of a wide beam ribbed slab can occur at an internal column either by punching shear or wide beam shear. Although a punching shear failure of a wide beam ribbed slab is very similar to that of a solid slab, the shear capacity is reduced relatively, because some of the potential shear failure surface is lost when it enters the ribbed section. Plastic theories for punching shear and wide beam shear were developed, which gave good agreement with the test failure loads. [ABSTRACT FROM AUTHOR]

With the primary aim to minimise environmental impacts from construction waste, this study was conducted in order to investigate the effects of recycled aggregates on concrete compressive and flexural tensile strengths. The outcomes indicate that recycled aggregates caused significant reductions in the attainment of concrete compressive strength (up to 21%) and flexural tensile strength (up to 39%) as aggregates replacement increases to 75%. [ABSTRACT FROM AUTHOR]

The Processor Configuration Problem (PCP) is a real life Constraint Optimization Problem. The task is to link up a finite set of processors into a network, whilst minimizing the maximum distance between these processors. Since each processor has a limited number of communication channels, a carefully planned layout will help reduce the overhead for message switching. In this paper, we present a Genetic Algorithm (GA) approach to the PCP. Our technique uses a mutation-based GA, a function that produces schemata by analyzing previous solutions, and an efficient data representation. Our approach has been shown to out-perform other published techniques in this problem. [ABSTRACT FROM AUTHOR]

OBJECTIVE. Airway management and endotracheal intubation may be required urgently when a patient deteriorates in an ambulance or aircraft during interhospital transfer or in a prehospital setting. The objectives of this study were: (1) to compare the effectiveness of conventional intubation by Macintosh laryngoscope in a moving ambulance versus that in a static ambulance; and (2) to compare the effectiveness of inverse intubation and GlideScope laryngoscopy with conventional intubation inside a moving ambulance. DESIGN. Comparative experimental study. SETTING. The experiment was conducted in an ambulance provided by the Auxiliary Medical Service in Hong Kong. PARTICIPANTS. A group of 22 doctors performed endotracheal intubation on manikins with Macintosh laryngoscope in a static and moving ambulance. In addition, they performed conventional Macintosh intubation, inverse intubation with Macintosh laryngoscope, and GlideScope intubation in a moving ambulance in both normal and simulated difficult airways. MAIN OUTCOME MEASURES. The primary outcome was the rate of successful intubation. The secondary outcomes were time taken for intubation, subjective glottis visualisation grading, and eventful intubation (oesophageal intubation, intubation time >60 seconds, and incisor breakage) with different techniques or devices. RESULTS. In normal airways, conventional Macintosh intubation in a static ambulance (95.5%), conventional intubation in a moving ambulance (95.5%), as well as GlideScope intubation in a moving ambulance (95.5%) were associated with high success rates; the success rate of inverse intubation was comparatively low (54.5%; P=0.004). In difficult airways, conventional Macintosh intubation in a static ambulance (86.4%), conventional intubation in a moving ambulance (90.9%), and GlideScope intubation in a moving ambulance (100%) were associated with high success rates; the success rate of inverse intubation was comparatively lower (40.9%; P=0.034). CONCLUSIONS. En-route intubation in an ambulance by conventional Macintosh laryngoscopy is superior to inverse intubation unless the cephalad access is impossible. GlideScope laryngoscopy appears to be associated with lower rates of eventful intubation in difficult airways and has better laryngoscopic view versus inverse intubation.

Since the Education Commission of the Hong Kong Special Administrative Region had proposed the educational reform in 2000, there is a new direction for school curriculum development. Lok Wah Catholic Primary School was one of the schools taking the health promoting school approach for educational reform. This paper aims to share information on how the School implemented the "Green Health Education Approach" to create a healthy learning environment for students.