Human settlement of the last glaciation on the Tibetan plateau

An archaeological site with 19 handprints and footprints of Homo sapiens and the remnant of a fireplace have been found on hot spring travertine at an elevation of 4200 m on the Tibetan plateau. The prints were pressed on soft travertine by humans. The age of the prints and fireplace is estimated to be around 20,000 years using the optically stimulated luminescence method. The result suggests that humans came to the plateau much earlier than was previously thought. This evidence of human settlement implies that the Tibetans occupy high plateau much earlier than the Andeans and the ice sheet did not cover the entire Tibetan plateau during the Last Glacial Maximum.published_or_final_versio

Research on multi-resolution texture model in three-dimensional GIS

2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Changes in the adsorption of bisphenol A, 17ɑ-ethinyl estradiol, and phenanthrene on marine sediment in Hong Kong in relation to the simulated sediment organic matter decomposition

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Knowledge-bases, places, spatial configurations and the performance of knowledge-intensive professional service firms

Working Pape

Adaptive Measurement Network for CS Image Reconstruction

Conventional compressive sensing (CS) reconstruction is very slow for its characteristic of solving an optimization problem. Convolu- tional neural network can realize fast processing while achieving compa- rable results. While CS image recovery with high quality not only de- pends on good reconstruction algorithms, but also good measurements. In this paper, we propose an adaptive measurement network in which measurement is obtained by learning. The new network consists of a fully-connected layer and ReconNet. The fully-connected layer which has low-dimension output acts as measurement. We train the fully-connected layer and ReconNet simultaneously and obtain adaptive measurement. Because the adaptive measurement fits dataset better, in contrast with random Gaussian measurement matrix, under the same measuremen- t rate, it can extract the information of scene more efficiently and get better reconstruction results. Experiments show that the new network outperforms the original one.Comment: 11pages,8figure

A numerical investigation on the damage identification of timber utility poles based on wavelet packet energy

Timber utility poles are traditionally used for electricity and telecommunication distribution. Due to the old age of many distribution networks, the health condition of these timber poles needs to be assessed. Non-destructive testing (NDT) methods based on stress wave propagation have successfully been used in practice for the condition assessment of timber poles. However, for the successful application of these methods for damage identification, some limitations exist. To overcome these limitations, this paper proposes the use of wavelet packet energy (WPE) for the stress wave data analysis and damage identification. WPE is a sensitive indicator for structural damage and has been used for damage detection in various types of structures. This paper presents a comprehensive investigation on the novel use of WPE for the damage identification in timber utility poles using finite element (FE) models. The research study comprises of the following investigations: i) a comparative study between 2D and 3D models, ii) a sensitivity study of mesh density for 2D models, and iii) a study of the novel WPE-based technique for damage detection in timber poles. The results of the new method clearly show the effectiveness of the proposed damage identification technique based on WPE

Application and improvement of conventional stress-wave-based non-destructive testing methods for the condition assessment of in-service timber utility poles

Timber utility poles represent a significant part of Australia’s infrastructure for power distribution and communication networks. Due to their advanced age, significant efforts are undertaken to prevent utility lines from failure. However, the lack of reliable tools for assessing the condition of in-service poles seriously jeopardizes the maintenance and asset management. Non-destructive testing (NDT) methods based on stress wave propagation can potentially offer simple and cost-effective tools for the condition assessment of in-service timber poles. Based on the impact direction and location, mainly two wave types can be excited in a pole, i.e. longitudinal and bending waves. A conventional stresswave- based method that analyses longitudinal waves is the Sonic Echo (SE) method; and a typical signal processing method for the analysis of bending waves (BW) is the Short Kernel Method (SKM). In this paper, firstly, the application of the conventional SE method and the BW method with SKM data analysis is investigated for the condition assessment of timber poles from a signal processing perspective. Secondly, to improve limitations of the current methods, the application of a multisensors array is proposed for more reliable and accurate results. The new method is validated on numerical data of a timber pole modelled with both isotropic and orthotropic material properties

Climate Variability and Its Effects on Gender and Coping Strategies in Baringo County, Kenya

Climate variability has often been described as one of the most pressing environmental challenges. Our lifestyles, economy, health, income, livelihood and our social well-being are all affected by climate. This paper therefore, assessed climate variability, its effect of gender and coping strategies they adopt in Baringo County, Kenya. Descriptive and inferential statistics were used in analyzing the data obtained for the study. Findings show that there is consisent decrease in rainfall and increase in temperature in recent times. Male gender dominates household decisions and roles such as land preparation, livestock keeping/feeding, pesticide application and fence construction in Baringo County, Kenya while the female gender dominates household roles such as water supply, domestic home chores and more of agricultural activities. Livestock migration was the major traditional coping strategy adopted in Baringo County. 56.8% of the respondents shows that cutting grasses for livestock was the major short term coping strategy adopted while Rainfall harvesting and storage (5.92%) was the least adopted in the studied area. Long term coping strategy to climate variability mostly adopted by the rural populace in is livestock migration (48.52%), it was also observed here that the least long term coping strategy adopted is finding alternative job as reputed by 4.44% of the respondents. Special intervention projects such as rain water harvesting techniques, drought resistant crops, short term crops etc, should be provided to rural populace/dwellers in Baringo County, and other parts of Kenya experiencing severe variability in climate, resulting to drought