bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polycrystalline silicon thin‐film solar cells: The future for photovoltaics?
Authors: Shi Z. , Wenham S. R. 
Published: July 2007

AbstractBased on performance, material availability, consumer acceptance, life expectancy, environmental considerations and the potential for low cost, thin‐film polycrystalline silicon solar cells are well placed to have a significant impact in the future. of key importance will be the achievement of performance targets, because module efficiencies of at least 15% are probably necessary in the long term for photovoltaics to have a significant impact in grid‐connected applications. Strategies for achieving these performance levels with mediocre material quality and only moderate surface passivation and light trapping are presented. the challenges associated with the supporting substrate choice and layer depostion techniques and structures are discussed and the psesent practices reviewed. Important considerations include device performance, cost, throughput, device area and simplicity of fabrication and operation. Promising efficiencies in the vicinity of 15% have already been demonstrated using a number of different crystalline silicon layer‐formation techniques. Novel device structures based on incorporation of narrow bandgap materials (Si/Ge alloys) or defect layers, quantum wells and the impurity photovoltaic effect are considered, with particular emphasis given to approaches that compensate for the current loss in thin‐film cells. It appears increasingly likely that polycrystalline silicon thin‐film solar cells will have an impact on the development of photovoltaics in the future and may in fact provide the means for the substantial cost reductions necessary for significant penetration into utility markets.
Polycrystalline silicon‐film™ solar cells: Present and future
Authors: Barnett Allen M. , Collins Sandra R. , Cotter Jeffrey E. , Ford David H. , Hall Robert B. , Rand James A. 
Published: July 2007

AbstractFuture crystalline silicon solar cells will have increased performance and reduced cost. Increased performance will come from thin silicon with light trapping, provided that it includes back‐surface passivation. Cost reduction will come from the growth of this thin silicon light‐trapping structure on a low‐cost substrate. the silicon will be polycrystalline. Solar cells formed with thin (< 50 μm) silicon active layers can produce higher conversion efficiencies at reduced material requirements than conventional ingot‐based silicon devices. This paper presents the essential features of high‐performance device design based on thin silicon layers, the design features of the Silicon‐Film−TM technology, the sequence of products that emerge from its development and recent results from the first commercial‐scale, large‐area (225 cm−2) Silicon‐Film−TM solar cell product.
New generation of high‐efficiency solar cells: Development, processing and marketing
Authors: Jordan D. , Nagle J. P. 
Published: July 2007

AbstractIn 1985, BP Solar Australia (BPSA) licensed and began commercialization of the high‐efficiency buried‐contact solar cell technology developed and patented by the University of New South Wales.−1 Small‐area cells of 18% efficiency were soon produced in BPSA's Brookvale laboratory, leading on to a 5‐year development period in Australia and the establishment of a pilot production facility within the BP Solar España facility in Madrid in 1989.This paper looks at the current technical and commercial situation within BPSA for this novel technology, and how its future is viewed relative to other processing technologies.
Reduction of the apparent shunt resistance effect in silicon concentrator solar cells
Authors: Terrón M. J. , Ĺuque A. 
Published: July 2007

AbstractSilicon solar cells of lowly doped base, under concentration, show a slope in the low voltage region. the slope varies with the irradiance and is similar in some aspects to that caused by a shunt resistance. This apparent shunt resistance reduces the fill factor and the efficiency. In consequence, such cells cannot operate effectively at concentrations above 20 suns.Actually, this apparent shunt resistance is due to the transition from low to high injection in the cell base. This is confirmed by an accurate simulation using the PC1D code. A semi‐quantitative model of the mechanism is developed. It is shown that by thinning the cells the mechanism is strongly reduced. Thin cells are fabricated virtually free of low voltage slope at concentrations of 80 suns.Also, the existing short‐circuit current sub‐linearity is avoided in the thinned cells.
Characteristics of a‐Si solar cells prepared by the super chamber at a high substrate temperature
Authors: Nishikuni Masato , Takahama Tsuyoshi , Okamoto Shingo , Ninomiya Kunimoto , Nishiwaki Hidenori , Tsuda Shinya , Takeoka Akio , Ohnishi Michotoshi , Nakano Shoichi , Kuwano Yukinori 
Published: July 2007

AbstractA new approach to high‐performance a‐Si solar cells was studied. a‐Si films prepared at a high substrate temperature (> 250°C) have a higher absorption coefficient and a low SiH2 bond density. the effect of deposition temperature on the open‐circuit voltage (Voc) has been investigated systematically for glass/SnO2 Ipin/metal and glass/metal/nip/indium tin oxide (ITO) structure a‐Si solar cells. The Voc is found to depend strongly on the thermal history of the p/i interface. A short‐circuit current of 19.5 mA/cm−−2 was achieved for an a‐Si solar cell using an a‐Si i‐layer with a thickness of 4000 Å, which was prepared at a substrate temperature of 270°C.
Accelerated publication 23.5% efficient silicon solar cell
Authors: Zhao Jianhua , Wang Aihua , Green Martin A. 
Published: July 2007

AbstractThe passivated emitter and rear locally diffused cell structure has been redesigned and has yielded independently confirmed one‐sun eficiencies of up to 23.5%, the highest ever for a silicon cell. A dotted front emitter contact design, PBr3 liquid‐source phosphorus diffusions and 400‐μm thick 10‐cm diameter wafers have contributed to this improvement. Some of the new cells have demonstrated open‐circuit voltages of 709 mV with an ‘inverted’ pyramid surface structure, the highest ever for a 23%‐efficiency silicon cell. Further improvement is expected in the near future.
Value of grid‐support photovoltaics to electric distribution lines
Authors: Travers Dean L. , Shugar Daniel S. 
Published: July 2007

AbstractThis paper reports on the results of using photovoltaic (PV) generation to provide grid support to electric distribution and transmission lines. the analytical methods presented in this paper have been developed to incorporate existing feeder rating methodologies, PV output data and a new evaluation protocol that assesses the effective load‐carrying capability of targeted PV in a grid‐support application. Research results were validated using the Photovoltaic for Utility Scale Applications (PVUSA) 500‐kW Kerman project. Findings indicate that targeted PV generation can reduce summer peaking distribution‐feeder line temperatures, which enables engineers to increase the effective capacity of distribution feeders under standard planning conditions. Evaluating specific feeder conditions with measured PV system output under standard planning conditions indicates PV full load‐carrying capability for the test case area for a PV output of up to 2 MW. For the line under investigation, the maximum allowable load increase is not expected to exceed 40% of the line capacity. the evaluation methodology, while applied to a specific line on a specific feeder, was designed to apply to a diverse set of lines and feeders under varying conditions.
Characterization and modeling of Cu(In, Ga)(S, Se)2‐based photovoltaic devices: A laboratory and industrial perspective
Authors: Tuttle J. R. , Sites J. R. , Delahoy A. , Shafarman W. , Baso B. , Fonash S. , Gray J. , Menner R. , Phillips J. , Rockett A. , Scofield J. , Shapiro F. R. , Singh P. , Suntharalingam V. , Tarrant D. , Walter T. , Wiedeman S. , Peterson T. M. 
Published: July 2007

AbstractThis contribution is a summary of a workshop convened to discuss the characterization and modeling of thin‐film CuInSe2(CIS)‐based solar cells, 17‐19 October 1993, in Estes Park, Colorado. the participants of the workshop are the authors of this paper. the subject matter was examined along four lines: device modeling, characterization, processing, and manufacturing issues. Fundamental numerical modeling has successfully guided device design efforts, including the design of variable band‐gap absorbers. Quantitative analysis, however, has been compromised by incomplete data on fundamental material properties. Phenomenological modeling and device characterization have sucessfully contributed to the understanding of the device physics. Although classified as a heterojunction device, the forward‐current recombination of the ZnO/CdS/CIS occurs almost exclusively in the space‐charge with diode quality factors ranging from 1.2 to 1.7 for good devices. the next generation of device modeling must incorporate two‐ and three‐dimensional effects. Recent fabrication work has focused on improving the CIS absorber and adding Ga and S to the matrix to increase its band‐gap. A better understanding of the ternary's fundamental properties is required to support the modeling efforts. Control of Ga and S introduction and the resulting absorber band‐gap profiles will facilitate the realization of optimized device designs. Inadequate understanding of fundamental device operation and process control at the laboratory level are amplified in the manufacturing environment. Modeling and characterization can identifv areas where corrective actions will result in improved performance and yield at the module level.
Zone‐melting recrystallization of silicon thin films for solar cell application
Authors: Ishihara T. , Arimoto S. , Kumabe H. , Murotani T. 
Published: July 2007

AbstractZone‐melting recrystallization (ZMR) has been applied successfully to fabricate a thin‐film silicon solar cell with high conversion efficiency that also has the potential to lower the material cost. It is found that seeding from an Si substrate during ZMR is not necessary for high‐quality thin‐film Si with a low defect density and the dominant (100) crystallographic orientation. This feature is very important because one can separate the thin‐film Si from the substrate in order to obtain a flexible solar cell and the substrate can be recycled. Lowering the scanning speed of the upper movable carbon strip heater has proved to be most effective for high‐quality crystal. In order to realize thin‐film Si solar cells, a 60‐μm thick Si active layer is deposited by chemical vapour deposition on recrystallized Si film. Pyramidal shape formation at the surface for light confinement by using (100) orientation and low‐energy H+ ion irradiation for the passivation of crystal defects has been applied to the fabrication of thin‐film Si solar cells and we achieved high conversion efficiencies of more than 14% for a 10 × 10 cm2 cell and 16% for a 2 × 2 cm2 cell.
Plasma etching: Safety, health and environmental considerations
Authors: Fthenakis V. M. , Moskowitz P. D. 
Published: July 2007

AbstractPlasma etching in the photovoltaic industries involves several inorganic and organic fluorides, chlorides and bromides, some of which are toxic, corrosive, or flammable. Nitrogen fluoride, a relatively new etching material, presents special concerns because it may form self‐ignitable mixtures with some flammable gases. In addition, non‐toxic compounds (e.g. Freon), can form toxic by‐products in a plasma environment. Another safety concern is failure of vacuum pumps caused by corrosive effluents, and occupational safety issues associated with cleaning traps and reactors. These issues are discussed in this paper and the applicable safety and environmental control options are outlined.
Azorellane diterpenoids from Laretia acaulis inhibit nuclear factor‐kappa B activity
Authors: Borquez Jorge , Loyola Luis A. , Morales Glauco , San‐Martín Aurelio , Roldan Raquel , Marquez Nieves , Muñoz Eduardo 
Published: July 2007

AbstractTranscription factor NF‐κB plays a key role in the inducible expression of genes mediating proinflammatory effects, and is thus an important target for the development of antiinflammatory drugs. Laretia acaulis (Cav.) Gill et Hook (Apiaceae) is a medicinal plant used in the high Andes mountains for different ailments such as diabetes, inflammation and for general pain. In addition to the known azorellanol (2) and 7‐deacetylazorellanol (4), 13‐epiazorellanol (1) was also isolated from the aerial part of this plant. Its structure was based on spectroscopic comparison with azorellanol (2) and by chemical characterization. While compounds 2 and 4 showed potent anti‐NF‐κB activity by targeting the activity of the IκBα kinase, compound 1 was completely inactive highlighting the importance of position 13 in the biological activities of this class of tetracyclic diterpenoids. Copyright © 2007 John Wiley & Sons, Ltd.
Retracted: Tissue culture of some lichens and screening of their antioxidant, antityrosinase and antibacterial properties
Authors: Behera B. C. , Verma Neeraj , Sonone Anjali , Makhija Urmila 
Published: July 2007

AbstractThe article above has been retracted by agreement between the authors, the Editors‐in Chief of Phytotherapy Research (PTR) and John Wiley & Sons, Ltd. The retraction has been agreed due to similarity of data between this article and the following article published in the journal Bioresource Technology (BITE); Antioxidant and antibacterial properties of some cultured lichens by B. C. Behera, Neeraj Verma, Anjali Sonone and Urmila Makhija. Bioresource Technology 99: 776‐784 (2008).
Although the submission to PTR was before that of BITE, the on‐line edition appeared first in BITE.
The Editorial policy of the journal is to publish only original data that has not been submitted elsewhere. Authors are reminded that this is in accordance with the strict guidelines outlined in our Instructions to Authors.

Elizabeth M Williamson
Editor in Chief, Phytotherapy Research.
The feedback view of business policy and strategy
Authors: Morecroft John D. W. 
Published: July 2007

AbstractA combination of administrative theory and traditional system dynamics modeling promises a flexible model‐based tool to assist businesses in designing policies and programs to support new strategic moves. Administrative theory helps clarify the firm's organization and decision‐making structure. System dynamics highlights feedback loops in the decision‐making structure and shows how structure is related to business behavior. With this dual conceptual framework, a business policy modeling project divides into two distinct phases, each of which has a value in policy analysis. Phase 1 is a descriptive survey of the firm's decision‐making structure, rather like traditional conceptualization but made richer by use of administrative theory. Phase 2 is conventional simulation modeling that builds on the phase 1 survey. Several business cases illustrate the kinds of policy insights that a phase 1 survey can provide. The article also comments on the value that a full‐fledged simulation model adds to the phase 1 analysis.
Notes on the teaching of system dynamics
Authors: Clauset Karl H. 
Published: July 2007

AbstractNotes and Insights is a forum for discussion and debate about current issues in the philosophy and application of the system dynamics approach, and a marketplace for the exchange of information about current research, policy issues, and teaching experiences. Manuscripts treating material particularly suited to presentation in short form (less than 2,000 words) should be sent to Erich Zahn. Betriebswirtschaftliches Institut. Universität Stuttgart, Herdweg 23, D‐7000 Stuttgart 1, West Germany.
Generic structures
Authors: Paich Mark 
Published: July 2007

AbstractIn this section the System Dynamics Review presents problems having the potential to stimulate system dynamics research. Articles may address real‐world dynamic problems that could be approached fruitfully from the system dynamics perspective, or methodological problems affecting the field. A paper submitted to the Research Problems section should concisely motivate and define a problem and start a process of conceptualization or formulation that can open the way for further studies. Manuscripts not exceeding 2,000 words should be sent to George P. Richardson, Department of Mathematics and Computer Science, Wheaton College, Norton, MA 02766, U.S.A.
Problems with causal‐loop diagrams
Authors: Richardson George P. 
Published: July 2007

AbstractFounded in the mid‐1950s, the field of system dynamics has intellectual roots reaching much further into the past. The Archives section of the Review seeks to publish material from that past which can contribute to current theory and practice. The section welcomes previously unpublished but deserving system dynamics work, classics from past system dynamics literature that should receive renewed attention, and previously published articles from other disciplines of particular significance to current system dynamicists. Contributions emphasizing the philosophy and theory of model building, validation, implementation, education, and generic structures are particularly encouraged. Submissions may range in length from notes to main articles but may be edited. Send suggested material, together with a brief introduction placing it in historical and current contexts, to John D. Sterman, System Dynamics Group, M.I.T. E40‐294, Cambridge, MA 02139, U.S.A.
Defining sociological concepts as variables for system dynamics modeling
Authors: Jacobsen Chanoch , Bronson Richard 
Published: July 2007

AbstractSocial structures and processes are generally described and analyzed in terms of verbal concepts. To simulate such phenomena in system dynamics models, the concepts must first be transformed into quantifiable variables. Useful intermediate steps in this process are specific but transferable nominal definitions, based on meaning analysis of the concepts. For modeling purposes, a well‐defined variable should be reliable and realistic, and have face validity. The relevance and importance of these criteria, long recognized in sociological research, are documented and illustrated with examples drawn from recently published work on a model of normative systems in industrialized societies.
A model to inform institutional resource allocation procedures
Authors: Galbraith Peter L. , Carss Brian 
Published: July 2007

AbstractNotes and Insights is a forum for discussion and debate about current issues in the philosophy and application of the system dynamics approach, and a marketplace for the exchange of information about current research, policy issues, and teaching experiences. Manuscripts treating material particularly suited to presentation in short form (less than 2,000 words) should be sent to Erich Zahn, Betriebswirtschaftliches Institut, Universität Stuttgart, Herdweg 23, D‐7000 Stuttgart 1, West Germany.
Break the cycle: Poverty causes population growth causes poverty
Authors: Meadows Donella 
Published: July 2007

AbstractDonella Meadows, who teaches at Dartmouth College, recently won a major award for excellence in journalism. The Champion‐Tuck Awards are given annually in the United States for the best reporting on business and economic issues. She won second prize in the 1986 competition for local or syndicated columnists for her weekly column “The Global Citizen,” which is published in the Valley News of Lebanon, New Hampshire, and appears in a number of newspapers in New England and elsewhere in the United States. The article printed here appeared in the Valley News, June 21, 1986.Dr. Rfeadolvs began writing “The Global Citizen” in 1983 on issues ranging from organic farming to causes of economic depression, from political revolution to preservation of tropic ecosystems. The columns are infused with a feedback view of the world and emphasize the endogenous. dynamic. and interconnected nature of the systems within which we live.
Portfolio simulation: A tool to support strategic management
Authors: Merten Peter P. , Löffler Reiner , Wiedmann Klaus‐Peter 
Published: July 2007

AbstractWe show that a quantitative portfolio simulation model can be used effectively in the allocation of investment funds in multibusiness firms. The portfolio simulation model, which is formulated with an extended system dynamics approach, further allows us to show severe limitations of qualitative portfolio approaches, such as that of the Boston Consulting Group (BCG). The simulation experiments demonstrate that it can be extremely dangerous for diversified companies to follow the investment suggestions typically drawn from the BCG portfolio matrix if competitors choose a course of action that is contradictory to normative situations. The simulation runs additionally show that in an economic depression a more flexible positioning strategy can yield much better results than the fixed positioning strategy typically used by the BCG.
System dynamics and heuristic optimisation in defence analysis
Authors: Wolstenholme E. F. , Al‐Alusi Abdul‐Sattar 
Published: July 2007

AbstractThe aim of this paper is to demonstrate the merits of using optimisation for policy design in system dynamics models. The approach has been applied to an existing defence model to design formation change strategies for an attacking force (Red) in response to indirect fire strategies applied by a defending force (Blue). The rationale behind the use of optimisation in system dynamics is presented, followed by a description of the optimisation software used. The model and its basic results are summarised, prior to describing the design and results of optimisation experiments applied to it. It is concluded that the optimisation approach can significantly contribute to the analysis by highlighting new interactions between the Red and Blue strategies. Originally Red's desire to stay in a fast‐moving, highdensity formation was seen primarily as being based on facilitating recovery of lost speed and hence momentum, when Blue's fire ceased. Additionally, however, it is shown here that this strategy is preferable because it also minimises the time over which Red is exposed to Blue's fire.
Lessons from system dynamics modeling
Authors: Forrester Jay W. 
Published: July 2007

AbstractThe power and utility of system dynamics is best achieved by going beyond a model to implications and generalizations that can be drawn from the process of modeling. System dynamics papers too often stop with the description of a model. But models should become part of a more persuasive communications process that interacts with people's mental models, creates new insights, and unifies knowledge. In doing so, modeling uses the full range of available information‐the mental data base and the written data base, as well as the numerical data base. The last century has been devoted to exploring the frontier of physical science. The next century will be the time for exploring the dynamic nature of social systems and using the resulting knowledge for improving institutions and economies.
Empirical and theoretical evidence of economic chaos
Authors: Chen Ping 
Published: July 2007

AbstractEmpirical and theoretical investigations of chaotic phenomena in macroeconomic systems are presented. Basic issues and techniques in testing economic aggregate movements are discussed. Evidence of low‐dimensional strange attractors is found in several empirical monetary aggregates. A continuous‐time deterministic model with delayed feedback is proposed to describe the monetary growth. Phase transition from periodic to chaotic motion occurs in the model. The model offers an explanation of the multiperiodicity and irregularity in business cycles and of the low dimensionality of chaotic monetary attractors. Implications for monetary control policy and a new approach to forecasting business cycles are suggested.