Injection locked Fabry-Perot laser diodes for WDM passive optical network spare function

In this paper, a protection scheme for transmitters in wavelength-division-multiplexing passive optical network (WDM-PON) has been proposed and demonstrated. If any downstream transmitter encounters problems at the central office (CO), the interrupted communication can be restored immediately by injecting a Fabry-Perot laser diode (FP-LD) with the upstream lightwave corresponding to the failure transmitter. Compared with the conventional methods, this proposed architecture provides a cost-effective and reliable protection scheme employing a common FP-LD. In the experiment, a 1 36 protection capability was implemented with a 2.5 Gbit/s downstream transmission capability. (C) 2009 Elsevier B.V. All rights reserved.

Overall optimization of high-speed semiconductor laser modules

Based on the high frequency techniques such as frequency response measurement, equivalent circuit modeling and packaging parasitics compensation, a comprehensive optimization method for packaging high-speed semiconductor laser module is presented in this paper. The experiments show that the small-signal magnitude frequency response of the TO packaged laser module is superior to that of laser diode in frequencies, and the in-band flatness and the phase-frequency linearity are also improved significantly.

Internal quantum efficiency analysis of solar cell by genetic algorithm

To investigate factors limiting the performance of a GaAs solar cell, genetic algorithm is employed to fit the experimentally measured internal quantum efficiency (IQE) in the full spectra range. The device parameters such as diffusion lengths and surface recombination velocities are extracted. Electron beam induced current (EBIC) is performed in the base region of the cell with obtained diffusion length agreeing with the fit result. The advantage of genetic algorithm is illustrated.

Photoionization of 1s electron and corresponding shake-up process in ground and excited lithium atoms

The cross sections of the 18 electron photoionization and corresponding shake-up processes for Li atoms in the ground state 1s(2)2s and excited states 1s(2)2p, 1s(2)3p, 1s(2)3p and 1s(2)3d are calculated using the multi-configuration Dirac-Fock method. The latest experimental photoelectron spectrum at hv = 100 eV [Cubaynes D et al. Phys. Rev. Lett. 99 (2007) 213004] has been reproduced by the present theoretical investigation excellently. The relative intensity of the shake-up satellites shows that the effects of correlation and relaxation become more important for the higher excited states of the lithium atom, which are explained very well by the spatial overlap of the initial and final state wavefunctions. In addition, strong dependence of the cross section on the atomic orbitals of the valence electrons are found, especially near the threshold.

Współpraca transgraniczna i regionalna w obszarze Morza Bałtyckiego w latach 1989 -2007

Wydział Nauk Politycznych i Dziennikarstwa

Współpraca i rywalizacja państw jako czynnik kształtujący bezpieczeństwo międzynarodowe w Azji Północno-Wschodniej na początku XXI wieku

Wydział Nauk Politycznych i Dziennikarstwa

Application description and policy model in collaborative environment for sharing of information on epidemiological and clinical research data sets.

BACKGROUND: Sharing of epidemiological and clinical data sets among researchers is poor at best, in detriment of science and community at large. The purpose of this paper is therefore to (1) describe a novel Web application designed to share information on study data sets focusing on epidemiological clinical research in a collaborative environment and (2) create a policy model placing this collaborative environment into the current scientific social context. METHODOLOGY: The Database of Databases application was developed based on feedback from epidemiologists and clinical researchers requiring a Web-based platform that would allow for sharing of information about epidemiological and clinical study data sets in a collaborative environment. This platform should ensure that researchers can modify the information. A Model-based predictions of number of publications and funding resulting from combinations of different policy implementation strategies (for metadata and data sharing) were generated using System Dynamics modeling. PRINCIPAL FINDINGS: The application allows researchers to easily upload information about clinical study data sets, which is searchable and modifiable by other users in a wiki environment. All modifications are filtered by the database principal investigator in order to maintain quality control. The application has been extensively tested and currently contains 130 clinical study data sets from the United States, Australia, China and Singapore. Model results indicated that any policy implementation would be better than the current strategy, that metadata sharing is better than data-sharing, and that combined policies achieve the best results in terms of publications. CONCLUSIONS: Based on our empirical observations and resulting model, the social network environment surrounding the application can assist epidemiologists and clinical researchers contribute and search for metadata in a collaborative environment, thus potentially facilitating collaboration efforts among research communities distributed around the globe.

A framework for revising preservice curriculum for nonphysician clinicians: The mozambique experience.

Mozambique, with approximately 0.4 physicians and 4.1 nurses per 10,000 people, has one of the lowest ratios of health care providers to population in the world. To rapidly scale up health care coverage, the Mozambique Ministry of Health has pushed for greater investment in training nonphysician clinicians, Tιcnicos de Medicina (TM). Based on identified gaps in TM clinical performance, the Ministry of Health requested technical assistance from the International Training and Education Center for Health (I-TECH) to revise the two-and-a-half-year preservice curriculum. A six-step process was used to revise the curriculum: (i) Conducting a task analysis, (ii) defining a new curriculum approach and selecting an integrated model of subject and competency-based education, (iii) revising and restructuring the 30-month course schedule to emphasize clinical skills, (iv) developing a detailed syllabus for each course, (v) developing content for each lesson, and (vi) evaluating implementation and integrating feedback for ongoing improvement. In May 2010, the Mozambique Minister of Health approved the revised curriculum, which is currently being implemented in 10 training institutions around the country. Key lessons learned: (i) Detailed assessment of training institutions' strengths and weaknesses should inform curriculum revision. (ii) Establishing a Technical Working Group with respected and motivated clinicians is key to promoting local buy-in and ownership. (iii) Providing ready-to-use didactic material helps to address some challenges commonly found in resource-limited settings. (iv) Comprehensive curriculum revision is an important first step toward improving the quality of training provided to health care providers in developing countries. Other aspects of implementation at training institutions and health care facilities must also be addressed to ensure that providers are adequately trained and equipped to provide quality health care services. This approach to curriculum revision and implementation teaches several key lessons, which may be applicable to preservice training programs in other less developed countries.

Climate change and food safety: A review

Climate change and variability may have an impact on the occurrence of food safety hazards at various stages of the food chain, from primary production through to consumption. There are multiple pathways through which climate related factors may impact food safety including: changes in temperature and precipitation patterns, increased frequency and intensity of extreme weather events, ocean warming and acidification, and changes in contaminants’ transport pathways among others. Climate change may also affect socio-economic aspects related to food systems such as agriculture, animal production, global trade, demographics and human behaviour which all influence food safety. This paper reviews the potential impacts of predicted changes in climate on food contamination and food safety at various stages of the food chain and identifies adaptation strategies and research priorities to address food safety implications of climate change. The paper concludes that there is a need for intersectoral and international cooperation to better understand the changing food safety situation and in developing and implementing adaptation strategies to address emerging risks associated with climate change.

Determining factors of the innovative behavior of cooperatives: an analysis of the case of Castilla y León

Cooperatives have a long historical experience in the Spanish economy and have demonstrated their ability to compete against traditional firms in the market. To maintain this capability, while taking advantage of the competitive advantages associated with their idiosyncrasies as social economy enterprises, they should take into consideration that the economy is increasingly globalized and increasingly knowledge-based, especially with regards to technological content. As a consequence, the innovative capacity appears to be a key aspect in order to be able to challenge competitors. This article characterizes the innovative behavior of cooperatives in the region of Castile and Leon and analyses the internal and external factors affecting their innovative performance, based on data from a survey of 581 cooperatives. The results of the empirical analysis, which is performed by multivariate binary logistic regression on various types of innovation, lead us to identify the size of the organizations, the existence of planning, the R & D activities and the human capital as the main determining factors.

An Enchanted Tool? Humanitarian Assistance and the ILC Draft Articles on the Protection of Persons in the Event of Disasters

Despite previous attempts at codification of international law regarding international responses to natural and human-made disasters, there is currently no binding international legal framework to regulate the provision of humanitarian assistance outside armed conflicts. Nevertheless, since the International Law Commission (ILC) included the protection of persons in the event of disasters on its programme of work in 2006, it has provisionally adopted eleven draft articles that have the potential to create binding obligations on states and humanitarian actors in disaster settings. Draft articles adopted include the definition of ‘a disaster’, the relationship of the draft articles to the international humanitarian law of armed conflict, recognition of the inherent dignity of the human person, and the duty of international cooperation. However, the final form of the draft articles has not been agreed. The Codification Division of the UN Office of Legal Affairs has proposed a framework convention format, which has seen support in the ILC and the UN General Assembly Sixth Committee. The overall aim of this article is to provide an analysis of the potential forms of international regulation open to the ILC and states in the context of humanitarian responses to disasters. However to avoid enchanting the ILC draft articles with unwarranted power, any examination of form requires an understanding of the substantive subject matter of the planned international regulation. The article therefore provides an overview of the international legal regulation of humanitarian assistance following natural and human-made disasters, and the ILC’s work to date on the topic. It then examines two key issues that remain to be addressed by the ILC and representatives of states in the UN General Assembly Sixth Committee. Drawing on the UN Guiding Principles on Internal Displacement, the development and implications of binding and non-binding international texts are examined, followed by an analysis of the suggested framework convention approach identified by the Special Rapporteur as a potential outcome of the ILC work.