An estimate of the number of tropical tree species

The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher’s alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼40,000 and ∼53,000, i.e. at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼19,000–25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼4,500–6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa

PENINGKATAN EFISIENSI PROSES PRODUKSI KERAJINAN BAMBU MENGGUNAKAN MESIN PEMBUAT LIDI DI KARTI AJI BAMBOO HANDYCRAFT

The purpose of this community services is to increase the efficiency of the production process of bamboo craft with a round stick making machine. Gains derived by a craftsman can accelerate the process of making bamboo handicraft. Gains derived by devotees is to help solve problems encountered in the process of manufacture of handicraft artisans. The process of making machines include: planning, manufacture, and testing. The material used is steel square profile 3 cm in size, profile steel elbow size 3 cm, the steel shaft of 64 mm diameter, Alluminium to make puley, 15 mm thick wooden board, and 8 mm thick steel plate. The tools used to make machines include lathes, drilling machines, saws machine, and electric welding machines. Machine performance testing done by measuring the sticks diameter and length are made, and measure the time required. The results of the manufacturing process is to have made a round stick making machine with long dimension of 90 mm, width 50 cm and 65 cm high. The machine can make a stick of bamboo with a diameter of 3 mm and 4 mm. Long bamboo stick, not limited or made in accordance with the length of the cut material. Machine capable of making a round bamboo stick with a uniform size within 2 minutes to 50 cm long stick

Diversity and summation of large number of energy saving lighting

Non-linear loads are replacing all linear loads while no emission limits are defined for low power devices such as energy saving lighting. The widespread use of lighting equipment results in high harmonic distortion of the power distribution network. This paper presents the emissions of an installation of many energy saving lights and the effect of emission of energy saving lights in general on the power distribution networ

High harmonic distortion in a new building due to a multitude of electronic equipment

In modern buildings virtually all electric loads are non-linear. Neither the applicable standards for supply of electrical energy nor those for consumption of electrical energy take into account the replacement of linear loads by non-linear loads. Low power equipment is exempted in standards assuming that all other (linear) loads dominate the power quality. In modern buildings there is a huge number of non-linear loads in lighting, monitor, computer and small power supplies and only a very limited number (or no) conventional linear loads. This is causing unacceptable interference with costly consequences. This paper analyzes current standards and the (exemptions for) harmonic current consumption of modern devices. The increase in harmonic distortion in a new building due to a multitude of non-linear equipment is shown. This forced the owner of the building to make costly changes in the power supply network

Large number of small non-linear power consumers causing power quality problems

In modern buildings virtually all electric loads are non-linear. The applicable standards for consumption of electrical energy do not take into account the replacement of linear loads by non-linear loads. The exemptions made in those standards for low power devices, and the widespread use of such devices result in a high harmonic distortion of the power distribution network. This paper presents the current waveform of several typical low power devices. It shows the increase in harmonic distortion in a new modern building due to a multitude of non-linear devices. Enlarging the supply by doubling the power capacity afterwards, resulted in a much lower harmonic distortion, at high costs

Laser-induced periodic surface structures: fingerprints of light localization

The finite-difference time-domain (FDTD) method is used to study the inhomogeneous absorption of linearly polarized laser radiation below a rough surface. The results are first analyzed in the frequency domain and compared to the efficacy factor theory of Sipe and coworkers. Both approaches show that the absorbed energy shows a periodic nature, not only in the direction orthogonal to the laser polarization, but also in the direction parallel to it. It is shown that the periodicity is not always close to the laser wavelength for the perpendicular direction. In the parallel direction, the periodicity is about λ/Re(ñ), with ñ being the complex refractive index of the medium. The space-domain FDTD results show a periodicity in the inhomogeneous energy absorption similar to the periodicity of the low- and high-spatial-frequency laser-induced periodic surface structures depending on the material's excitation

Microstructural characterization of surface damage through ultra-short laser pulses

Electron back-scatter diffraction (EBSD) technique, commonly used to study the microstructural characteristics of materials, was employed for the investigation of the surface damage induced through ultra-short laser pulses. Single-crystal silicon surface was irradiated with an Ytterbium-doped YAG (Trumpf-TruMicro 5050) laser source generating laser pulses of 6.7 ps duration, a 1030 nm wavelength and linear polarization. The laser fluence level was set to values lower than the single-pulse modification threshold of the material. The laser pulses were delivered on the surface at conditions of lateral displacement, i.e. a train of laser pulses with a partial overlap (laser track). This approach made it possible to investigate the early stages of modification of the surface. Scanning electron microscope equipped with a field emission gun (Philips XL30 SEM FEG) and EDAX-TSL EBSD system was used for inspection of the surface modifications initiated with pulsed laser radiation. Depth of the generation of back-scattered electrons at different acceleration voltages of the primary beam was estimated by the use of Monte-Carlo simulation. Trajectories of primary and back-scattered electrons in a flat Si surface were generated at an angle of 74º from the surface normal, which is the angle used for the EBSD observations. High sensitivity of EBSD signal allows an estimate of the depth and intensity of the laser induced damage to the crystal lattice. It is found that the thickness of amorphous layer increases gradually with a distance from the feature center. The similarity of surface damage profiles observed at different accelerating voltages of the primary beam indicates that the damage is formed via a gradual crystal damage accumulation in subsurface layer and via the formation and growth of an amorphous layer from the surface

A bilingual dictionary with enriched lexical information

Fluidic self-alignment of micro-components relies on creating a receptor site that is able to confine a liquid droplet. When a micro-component is brought in contact with the droplet, capillary forces move the component to its final position. A method to stop the advancing of a liquid from a receptor site, consists of creating geometrical features, such as edges around the site. A picosecond pulsed laser source was used to create suitable edges in a metallic and a polyimide substrate. Subsequently, the self-alignment capabilities of these sites were tested. The receptor sites in polyimide showed the highest success rat

Water-Activated Semiquinone Formation and Carboxylic Acid Dissociation in Melanin Revealed by Infrared Spectroscopy

Eumelanin is a widespread biomacromolecule pigment in the biosphere and has been widely investigated for numerous bioelectronics and energetic applications. Many of these applications depend on eumelanin’s ability to conduct proton current at various levels of hydration. The origin of this behavior is connected to a comproportionation reaction between oxidized and reduced monomer moieties and water. A hydration-dependent FTIR spectroscopic study on eumelanin is presented herein, which allows for the first time tracking the comproportionation reaction via the gradual increase of the overall aromaticity of melanin monomers in the course of hydration. We identified spectral features associated with the presence of specific “one and a half” CO bonds, typical for o-semiquinones. Signatures of semiquinone monomers with internal hydrogen bonds and that carboxylic groups, in contrast to semiquinones, begin to dissociate at the very beginning of melanin hydration were indicated. As such, we suggest a modification to the common hydration-dependent conductivity mechanism and propose that the conductivity at low hydration is dominated by carboxylic acid protons, whereas higher hydration levels manifest semiquinone protons