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Strategic, tactical decisions and information in Rapid Manufacturing supply chain
The efficiency and agility of its supply chain is vital to the commercial success of any product. Sharing strategic and tactical information effectively within the supply chain is often a key factor in achieving this goal. This paper proposes a framework to identify strategic, tactical decisions and information. The framework is used to conduct a sector based analysis of the Rapid Manufacturing (RM) industry. The decisions and information identified include amongst others various supply chain strategies and technical information
Quantum transport across van der Waals domain walls in bilayer graphene
Bilayer graphene can exhibit deformations such that the two graphene sheets
are locally detached from each other resulting in a structure consisting of
domains with different inter-layer coupling. Here we investigate how the
presence of these domains affect the transport properties of bilayer graphene.
We derive analytical expressions for the transmission probability, and the
corresponding conductance, across walls separating different inter-layer
coupling domain. We find that the transmission can exhibit a valley-dependent
layer asymmetry and that the domain walls have a considerable effect on the
chiral tunnelling properties of the charge carriers. We show that transport
measurements allow one to obtain the strength with which the two layers are
coupled. We performed numerical calculations for systems with two domain walls
and find that the availability of multiple transport channels in bilayer
graphene modifies significantly the conductance dependence on inter-layer
potential asymmetry.Comment: 20 pages, 24 Figure
The whistler nozzle phenomenon
The whistler nozzle is a simple device which can induce jet self-excitations of controllable amplitudes and frequencies and appears highly promising for many applications involving turbulent transport, combustion and aerodynamic noise. The characteristics of this curious phenomenon are documented for different values of the controlling parameters and attempts to explain the phenomenon. It is shown that the whistler excitation results from the coupling of two independent resonance mechanisms: shear-layer tone resulting from the impingement of the pipe-exit shear layer on the collar lip, and organ-pipe resonance of the pipe-nozzle. The crucial role of the shear-layer tone in driving the organ-pipe resonance is proven by reproducing the event in pipe-ring and pipe-hole configurations in the absence of the collar. It is also shown that this phenomenon is the strongest when the self-excitation frequency matches the preferred mode of the jet
Human-centric light sensing and estimation from RGBD images: the invisible light switch
Lighting design in indoor environments is of primary importance for at least two reasons: 1) people should perceive an adequate light; 2) an effective lighting design means consistent energy saving. We present the Invisible Light Switch (ILS) to address both aspects. ILS dynamically adjusts the room illumination level to save energy while maintaining constant the light level perception of the users. So the energy saving is invisible to them. Our proposed ILS leverages a radiosity model to estimate the light level which is perceived by a person within an indoor environment, taking into account the person position and her/his viewing frustum (head pose). ILS may therefore dim those luminaires, which are not seen by the user, resulting in an effective energy saving, especially in large open offices (where light may otherwise be ON everywhere for a single person). To quantify the system performance, we have collected a new dataset where people wear luxmeter devices while working in office rooms. The luxmeters measure the amount of light (in Lux) reaching the people gaze, which we consider a proxy to their illumination level perception. Our initial results are promising: in a room with 8 LED luminaires, the energy consumption in a day may be reduced from 18585 to 6206 watts with ILS (currently needing 1560 watts for operations). While doing so, the drop in perceived lighting decreases by just 200 lux, a value considered negligible when the original illumination level is above 1200 lux, as is normally the case in offices
Design and Development of Hand and Foot Contamination Monitor
A hand and foot contamination monitor is a health physics instrument to provide detection and measurement of beta-gamma contamination on the palm of each hand and on the bottom surface of both feet/shoes. There are four channels of detection for two hands and two feet. Four G-M detectors have been used in a single unit to cover the whole area of hand and feet. A regulated high voltage DC power supply (900 V) has been designed using the PIC12F675 microcontroller to operate the pancake Geiger-Müller detectors. The reading is displayed on a linearly scaled 0-100 Bq/cm2 analog panel meter. The monitor detects beta–gamma radiation emitted by radioactive materials, and if the detected value exceeds a preset level, the monitor sounds an alarm and displays a reading in the respective panel meter. Indicator lamps are used to show the status of contamination. The performance of the system has been tested by using pulse generator and by flat surface radioactive calibration sources. Electronic linearity, detection efficiency, response to the contamination, calibration factor and percentage of error has been measured. Test results were satisfactory and the present system can be used instead of similar imported instruments. Received: 21 May 2014; Revised: 21 August 2014; Accepted: 22 August 201
An Analysis of Factors Determining Competitiveness: the Case of the Indonesian Palm Oil Industry
IndonesianKajian ini menganalisis faktor-faktor yang mempengaruhi daya saing industri kelapa sawit Indonesia di pasar Internasional. Kerangka kajian ini menggabungkan pendekatan teori perdagangan neo-klasik dan manajemen strategis dalam menganalisis daya saing Internasional pada tingkat industri. Penelitian ini menunjukan bahwa daya saing global industri kelapa sawit di Indonesia dapat dijelaskan oleh produktifitas tenaga kerja, nilai tukar rupiah, dan rasio konsentrasi empat Perusahaan. Campur tangan pemerintah dalam bentuk penentuan harga alokasi dalam negeri juga merupakan faktor yang sangat penting dan berpengaruh negatif pada daya saing global industri kelapa sawit di Indonesia.EnglishThis paper analyses factors that determine the competitiveness of the Indonesian palm oil industry including the effect of government interventions. The conceptual framework used in this study combines neo-classical trade and strategic management approaches for analyzing competitiveness at the industry level. This study shows that the competitiveness of the Indonesian palm oil industry can be explained by its labor productivity, the real exchange rates, and the four-firm concentration ratio. It is shown that government interventions--in the form of domestic allocation prices--have significant and negative effects on the competitiveness of the palm oil industry
Design and Development of Hand and Foot Contamination Monitor
A hand and foot contamination monitor is a health physics instrument to provide detection and measurement of beta-gamma contamination on the palm of each hand and on the bottom surface of both feet/shoes. There are four channels of detection for two hands and two feet. Four G-M detectors have been used in a single unit to cover the whole area of hand and feet. A regulated high voltage DC power supply (900 V) has been designed using the PIC12F675 microcontroller to operate the pancake Geiger-Müller detectors. The reading is displayed on a linearly scaled 0-100 Bq/cm2 analog panel meter. The monitor detects beta–gamma radiation emitted by radioactive materials, and if the detected value exceeds a preset level, the monitor sounds an alarm and displays a reading in the respective panel meter. Indicator lamps are used to show the status of contamination. The performance of the system has been tested by using pulse generator and by flat surface radioactive calibration sources. Electronic linearity, detection efficiency, response to the contamination, calibration factor and percentage of error has been measured. Test results were satisfactory and the present system can be used instead of similar imported instruments. Received: 21 May 2014; Revised: 21 August 2014; Accepted: 22 August 201
Performance of socially responsible investment funds in China: A comparison with traditional funds
This paper empirically examines and compares social responsibility investment funds to traditional funds, and explores the performance of the existing social responsibility investment funds in China. Based on 64 social responsibility investment funds (SRI Funds) and 64 traditional funds, this paper extracts the data of the sample fund from the fourth quarter of 2016 to the fourth quarter of 2019 as sample data to conduct a comparative analysis of the difference between the SRI fund and the traditional fund in terms of return and risk, and to then empirically study the performance of the funds. The results show that the difference between the return of China’s socially responsible investment funds and the traditional funds is insignificant, and the risk of socially responsible investment funds is significantly lower than that of traditional funds. The regression analysis is also carried out on a model of social responsibility as a factor affecting the performance of the funds. Subsequently, the results show that social responsibility has a significant positive impact on the fund’s return in the Chinese market
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