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This paper considers a joint pollution-routing with time windows and speed optimization problem (PRP-SO) where vehicle speed, payload, and road grade influence fuel costs and emissions. We present two advanced optimization methods (i.e., approximate and exact) for solving the PRP-SO. The approximate strategy solves large-scale instances of the problem with a Tabu search-based metaheuristic coupled with an efficient fixed-sequence speed optimization algorithm. The second strategy consists of a tailored branch-and-price (BP) algorithm to manage speed optimization within the pricing problem. We test both methods on modified Solomon benchmarks and newly constructed real-life instance sets. Our BP algorithm successfully solves the majority of instances involving up to 50 customers and many instances with 75 and 100 customers. The heuristic can find near-optimal solutions to all instances and requires less than one minute of computational time per instance. Results on real-world instances suggest several managerial insights. First, fuel savings of up to 53% can be achieved when explicitly considering arc payloads and road grades. Second, fuel savings and emission reduction can be achieved by scheduling uphill customers later along the routes. Lastly, we show that ignoring elevation information when planning routes leads to highly inaccurate fuel consumption estimates

The Capacitated Lot-Sizing Problem (CLSP) and its variants are important and challenging optimization problems. Constructive heuristics are known to be the most intuitive and fastest methods for finding good feasible solutions for the CLSPs and therefore are often used as a subroutine in building more sophisticated exact or metaheuristic approaches. Classical constructive heuristics, such as period-by-period heuristics and lot elimination heuristics, are widely used by researchers. This paper introduces four perturbation strategies to the period-by-period and lot elimination heuristics to further improve the solution quality. We propose a new procedure to automatically adjust the parameters of the randomized period-by-period (RPP) heuristics. The procedure is proved to offer better solutions with reduced computation times by improving time-consuming parameter tuning phase. Combinations of the self-adaptive RPP heuristics with Tabu search and lot elimination heuristics are tested to be effective. Computational experiments provided high-quality solutions with a 0.88% average optimality gap on benchmark instances of 12 periods and 12 items, and an optimality gap within 1.2% for the instances with 24 periods and 24 items.

Purpose Industrial implementation of continuous oral solid dosage form manufacturing has been impeded by the poor powder flow properties of many active pharmaceutical ingredients (APIs). Microfluidic droplet-based particle synthesis is an emerging particle engineering technique that enables the production of neat or composite microparticles with precise control over key attributes that affect powder flowability, such as particle size distribution, particle morphology, composition, and the API’s polymorphic form. However, the powder properties of these microparticles have not been well-studied due to the limited mass throughputs of available platforms. In this work, we produce spherical API and API-composite microparticles at high mass throughputs, enabling characterization and comparison of the bulk powder flow properties of these materials and greater understanding of how particle-scale attributes correlate with powder rheology. Methods A multi-channel emulsification device and an extractive droplet-based method are harnessed to synthesize spherical API and API-excipient particles of artemether. As-received API and API crystallized in the absence of droplet confinement are used as control cases. Particle attributes are characterized for each material and correlated with a comprehensive series of powder rheology tests. Results The droplet-based processed artemether particles are observed to be more flowable, less cohesive, and less compressible than conventionally synthesized artemether powder. Co-processing the API with polycaprolactone to produce composite microparticles reduces the friction of the powder on stainless steel, a common equipment material. Conclusions Droplet-based extractive solidification is an attractive particle engineering technique for improving powder processing and may aid in the implementation of continuous solid dosage form manufacturing. Graphical abstract

In the vehicle routing problem with multiple time windows (VRPMTW), a single time window must be selected for each customer from the multiple time windows provided. Compared with classical vehicle routing problems with only a single time window per customer, multiple time windows increase the complexity of the routing problem. To minimize the duration of any given route, we present an exact polynomial time algorithm to efficiently determine the optimal start time for servicing each customer. The proposed algorithm has a reduced worst-case and average complexity than existing exact algorithms. Furthermore, the proposed exact algorithm can be used to efficiently evaluate neighborhood operations during a local search resulting in significant acceleration. To examine the benefits of exact neighborhood evaluations and to solve the VRPMTW, the proposed algorithm is embedded in a simple metaheuristic framework generating numerous new best known solutions at competitive computation times.

This paper investigates a shift rostering problem – the assignment of staff to shifts over a planning horizon such that work rules are observed. Traditional integer-programming models are not able to solve shift rostering problems effectively for large number of staff and feasible shift patterns. We formulate work rules in terms of newly-proposed prohibited meta-sequences and resource constraints. A graph-based formulation and a specialized graph construction algorithm are proposed where the set of feasible shift patterns is represented by paths of a graph. The formulation size depends on the structure of the work-rule constraints and is independent of the number of staff. This approach results in smaller networks allowing large-scale rostering problems with hard constraints to be solved efficiently using standard commercial solvers. Moreover, it allows finding multiple optimal solutions which are beneficial for managerial decision makers. Computational results show that the proposed approach can obtain new best-known solutions and identify proven optimal solutions for almost all NSPLIB instances at significantly lower CPU times.

This paper investigates a shift rostering problem – the assignment of staff to shifts over a planning horizon such that work rules are observed. Traditional integer-programming models are not able to solve shift rostering problems effectively for large number of staff and feasible shift patterns. We formulate work rules in terms of newly-proposed prohibited meta-sequences and resource constraints. A graph-based formulation and a specialized graph construction algorithm are proposed where the set of feasible shift patterns is represented by paths of a graph. The formulation size depends on the structure of the work-rule constraints and is independent of the number of staff. This approach results in smaller networks allowing large-scale rostering problems with hard constraints to be solved efficiently using standard commercial solvers. Moreover, it allows finding multiple optimal solutions which are beneficial for managerial decision makers. Computational results show that the proposed approach can obtain new best-known solutions and identify proven optimal solutions for almost all NSPLIB instances at significantly lower CPU times.

In the vehicle routing problem with multiple time windows (VRPMTW), a single time window must be selected for each customer from the multiple time windows provided. Compared with classical vehicle routing problems with only a single time window per customer, multiple time windows increase the complexity of the routing problem. To minimize the duration of any given route, we present an exact polynomial time algorithm to efficiently determine the optimal start time for servicing each customer. The proposed algorithm has a reduced worst-case and average complexity than existing exact algorithms. Furthermore, the proposed exact algorithm can be used to efficiently evaluate neighborhood operations during a local search resulting in significant acceleration. To examine the benefits of exact neighborhood evaluations and to solve the VRPMTW, the proposed algorithm is embedded in a simple metaheuristic framework generating numerous new best known solutions at competitive computation times.

The vehicle routing problem with private fleet and common carrier (VRPPC) is a generalization of the classical vehicle routing problem in which the owner of a private fleet can either visit a customer with one of the owner's vehicles or assign the customer to a common carrier. The latter case occurs if the demand exceeds the total capacity of the private fleet or if it is more economically convenient to do so. The owner's objective is to minimize the variable and fixed costs for operating the owner's fleet plus the total cost charged by the common carrier. This family of problems has many practical applications, particularly in the design of last-mile distribution services and has received some attention in the literature, in which some heuristics were proposed. We extend here the VRPPC by considering more realistic cost structures that account for quantity discounts on outsourcing costs and by considering time windows resulting in a rich VRPPC (RVRPPC). We present an exact approach based on a branch-and-cut-and-price algorithm for the RVRPPC and test the algorithm on instances from the literature.

The vehicle routing problem with private fleet and common carrier (VRPPC) is a generalization of the classical vehicle routing problem in which the owner of a private fleet can either visit a customer with one of the owner's vehicles or assign the customer to a common carrier. The latter case occurs if the demand exceeds the total capacity of the private fleet or if it is more economically convenient to do so. The owner's objective is to minimize the variable and fixed costs for operating the owner's fleet plus the total cost charged by the common carrier. This family of problems has many practical applications, particularly in the design of last-mile distribution services and has received some attention in the literature, in which some heuristics were proposed. We extend here the VRPPC by considering more realistic cost structures that account for quantity discounts on outsourcing costs and by considering time windows resulting in a rich VRPPC (RVRPPC). We present an exact approach based on a branch-and-cut-and-price algorithm for the RVRPPC and test the algorithm on instances from the literature.

The widely used SAP BusinessObjects Dashboards software lets you transform data from any source into interactive dashboards.The recipes begin by covering best practices for using the SAP BusinessObjects Dashboards spreadsheet. The book then guides you through the exploration of various data visualization components and dashboard interactivity, as well as using alerts, dashboard connectivity, publishing the dashboard, and making the most of the aesthetics of the dashboard. Finally, the recipes conclude by considering the most important add-ons available for SAP BusinessObjects Dashboards, performance tuning, and tips on increasing development productivity.

The widely used SAP BusinessObjects Dashboards software lets you transform data from any source into interactive dashboards.The recipes begin by covering best practices for using the SAP BusinessObjects Dashboards spreadsheet. The book then guides you through the exploration of various data visualization components and dashboard interactivity, as well as using alerts, dashboard connectivity, publishing the dashboard, and making the most of the aesthetics of the dashboard. Finally, the recipes conclude by considering the most important add-ons available for SAP BusinessObjects Dashboards, performance tuning, and tips on increasing development productivity.

The widely used SAP BusinessObjects Dashboards software lets you transform data from any source into interactive dashboards.The recipes begin by covering best practices for using the SAP BusinessObjects Dashboards spreadsheet. The book then guides you through the exploration of various data visualization components and dashboard interactivity, as well as using alerts, dashboard connectivity, publishing the dashboard, and making the most of the aesthetics of the dashboard. Finally, the recipes conclude by considering the most important add-ons available for SAP BusinessObjects Dashboards, performance tuning, and tips on increasing development productivity.

Academic research on (s,S) inventory policies for multi-echelon distribution networks with deterministic lead times, backordering, and fill rate constraints is limited. Inspired by a real-life Dutch food retail case we develop a simulation-optimization approach to optimize (s,S) inventory policies in such a setting. We compare the performance of a Nested Bisection Search (NBS) and a novel Scatter Search (SS) metaheuristic using 1280 instances from literature and we derive managerial implications from a real-life case. Results show that the SS outperforms the NBS on solution quality. Additionally, supply chain costs can be saved by allowing lower fill rates at upstream echelons.

Academic research on (s,S) inventory policies for multi-echelon distribution networks with deterministic lead times, backordering, and fill rate constraints is limited. Inspired by a real-life Dutch food retail case we develop a simulation-optimization approach to optimize (s,S) inventory policies in such a setting. We compare the performance of a Nested Bisection Search (NBS) and a novel Scatter Search (SS) metaheuristic using 1280 instances from literature and we derive managerial implications from a real-life case. Results show that the SS outperforms the NBS on solution quality. Additionally, supply chain costs can be saved by allowing lower fill rates at upstream echelons.

This guide to SAP BusinessObjects Dashboards 4.0 (formerly Xcelsius )is a cookbook packed full of practical recipes written in a clear, concise manner with annotated examples to empower readers to quickly accomplish specific dashboard tasks. If you are a developer with a good command and knowledge of creating dashboards, but are not yet an advanced Dashboard Design user, then this is the perfect book for you. You should have a good working knowledge of Microsoft Excel as well as knowledge of basic dashboard practices, though experience of Dashboard Design as a specific dashboard tool is not essential.

This guide to SAP BusinessObjects Dashboards 4.0 (formerly Xcelsius )is a cookbook packed full of practical recipes written in a clear, concise manner with annotated examples to empower readers to quickly accomplish specific dashboard tasks. If you are a developer with a good command and knowledge of creating dashboards, but are not yet an advanced Dashboard Design user, then this is the perfect book for you. You should have a good working knowledge of Microsoft Excel as well as knowledge of basic dashboard practices, though experience of Dashboard Design as a specific dashboard tool is not essential.

This guide to SAP BusinessObjects Dashboards 4.0 (formerly Xcelsius )is a cookbook packed full of practical recipes written in a clear, concise manner with annotated examples to empower readers to quickly accomplish specific dashboard tasks. If you are a developer with a good command and knowledge of creating dashboards, but are not yet an advanced Dashboard Design user, then this is the perfect book for you. You should have a good working knowledge of Microsoft Excel as well as knowledge of basic dashboard practices, though experience of Dashboard Design as a specific dashboard tool is not essential.

The papers in this book provide a valuable and insightful review of the People s Liberation Army s (PLA) many impressive advances over the past decade. Solid scholarship on changes taking place in the PLA helps us understand how the Chinese view the employment of military power to support broader policy aims. A historical review of patterns and developments in training, operations, acquisitions, and political military relations can greatly assist that understanding. The outstanding work in this jointly sponsored study is an important contribution toward this end. This volume provides unique insights into the PLA s achievements over the span of Hu Jintao s tenure as Central Military Commission Chair from 2002 to 2012. This period saw a remarkable growth in capabilities and a critical expansion in the military s missions. The PLA increased its adoption of information technologies and advanced sensors into its modernization efforts. It also improved its ability to carry out joint training and missions other than war. Reflecting developments in the Chinese Communist Party, the PLA also experienced important changes in its political focus and mission. Most significantly, Hu Jintao introduced the historic missions, which oriented the PLA toward a much greater international mission than it had previously undertaken. Supporting this new international mission, the PLA expanded its participation in international military exercises, as well as peacekeeping operations and humanitarian assistance and disaster relief missions abroad, including its first ever permanent naval deployment abroad in the counterpiracy missions in the Gulf of Aden. Understanding how the PLA matured and developed in the Hu era is critical to understanding the PLA today, and for identifying opportunities to further cooperation between our two militaries.

This thesis studies three routing and scheduling problems arising in manpower and transportation planning. These problems are rooted in real applications, and carry interesting characteristics. By exploiting the structures of the problems, this thesis provides effective mathematical models and algorithms for solving the problems practically. Managerial insights are developed via extensive computational tests and sensitivity analyses. Effective scheduling of staff can generate considerable saving where unnecessary costs due to misallocation of staff to the demand are reduced. The second chapter of this thesis studies the Shift Rostering Problem—the assignment of staff to shifts over a planning horizon such that work rules are observed. In view of the special structure of the work-rule constraints, we model work rules in terms of prohibited meta-sequences and resource constraints. A novel graph-based formulation is proposed where the formulation size depends on the structure of the work-rule constraints and is independent of the number of staff. This is particularly beneficial when the work rules possess sufficient structure that results in a small formulation. For some cases when the canonical formulation could not solve in a reasonable time, our approach can find optimal solutions in a few minutes. Vehicle routing problems occur frequently in the delivery and collection of items between a central depot and a number of customer locations. Motivated from the distribution of beer and malt beverages in China, the third chapter of this thesis studies a time-constrained heterogeneous vehicle routing problem on a multigraph. Parallel arcs represent Pareto-optimal paths between two locations, with various travel times and costs. We provide a mixed-integer linear programming formulation of the problem and propose a tabu search heuristic for its solution. The tabu search is designed to address the parallel arc structure on the network, which necessitates modifications of the

This analysis has four objectives: first, it puts the key trends of Asia-Pacific s geo-economic, political, and security affairs in perspective; second, it highlights the defining aspects in this region's complicated interstate relations; third, it points out the dilemmas confronting the key players in the region; and fourth, it draws attention to the most dangerous potential impacts of the region's outstanding conflicts.

Learning by Doing: The PLA Trains at Home and Abroad is the latest volume in a series on the PLA produced by the Strategic Studies Institute (SSI), The National Bureau of Asian Research (NBR), and the United States Pacific Command (USPACOM). The papers presented here are a timely and critical look at an evolving and expanding Chinese military and provide context for the changes we may yet see as the PLA continues to modernize. As the USPACOM Commander, I seek to better understand China in aspects that further our ability to find common areas of interest, reduce miscalculation, and contribute to regional stability. Greater insight into the PLA is essential to this effort. As the Chinese military matures, grows, and ventures farther from China s territory, the regional and global implications for the United States and USPACOM, as well as our allies and partners will be complex, yet critical to our understanding of China s evolving international role and influence. Therefore, accurate and timely assessments of the changes taking place within the PLA are essential to understanding how the Chinese are matching military power with their broader policy aims. The outstanding scholarship in this jointly-sponsored study by SSI, NBR, and USPACOM is an important contribution toward this end. The judgments in this volume provide unique and valuable insights on how the PLA is adapting its training to its perception of the security environment. This does not just include how it is resourcing, organizing, and training its forces, but also how the PLA thinks about warfare and the threats they currently face. Through participation in international military exercises, as well as peacekeeping operations (PKO) and humanitarian assistance and disaster relief (HADR) missions abroad, the PLA is gaining greater experience in carrying out a broader spectrum of missions.

The annual Conference on the Chinese People's Liberation Army (PLA) took place at the U.S. Army War College (USAWC), in Carlisle, Pennsylvania, on October 22-24, 2010.1 The topic for this year's conference was the PLA's lessons from Other People's Wars. Participants at the conference sought to discern what lessons the PLA has been learning from the strategic and operational experiences of the armed forces of other countries during the past 3 decades.

This analysis discusses the nature of U.S.-China relations in the context of an ongoing power transition between these two great powers, the rise of China and its impact, China s tortuous experience during its transition to modernity, U.S.-China conflicts over the two nations core interests, and the future of the U.S.- China power transition.

This guide to SAP BusinessObjects Dashboards 4.0 (formerly Xcelsius )is a cookbook packed full of practical recipes written in a clear, concise manner with annotated examples to empower readers to quickly accomplish specific dashboard tasks. If you are a developer with a good command and knowledge of creating dashboards, but are not yet an advanced Dashboard Design user, then this is the perfect book for you. You should have a good working knowledge of Microsoft Excel as well as knowledge of basic dashboard practices, though experience of Dashboard Design as a specific dashboard tool is not essential.

We present the results of a low-resolution spectral abundance study of 25 stars in the Bootes I dwarf spheroidal (dSph) galaxy. The data were obtained with the LRIS instrument at Keck Observatory, and allow us to measure [Fe/H], [C/Fe], and [alpha/Fe] for each star. We find both a large spread in metallicity (2.1 dex in [Fe/H]) as well as the low average metallicity in this system, <[Fe/H]>=-2.59, matching previous estimates. This sample includes a newly discovered extremely metal-poor star, with [Fe/H]=-3.8, that is one of the most metal-poor stars yet found in a dSph. We compare the metallicity distribution function of Bootes I to analytic chemical evolution models. While the metallicity distribution function of Bootes I is best fit by an Extra Gas chemical evolution model, leaky-box models also provide reasonable fits. We also find that the [alpha/Fe] distribution and the carbon-enhanced metal-poor fraction of our sample (12%) are reasonable matches to Galactic halo star samples in the same metallicity range, indicating that at these low metallicities, systems like the Bootes I ultra-faint dSph could have been contributors to the Galactic halo., Comment: ApJ, accepted. 10 pages, in emulate apj format

We present analysis of high-resolution spectra of a sample of stars in the globular cluster M5 (NGC 5904). The sample includes stars from the red giant branch (seven stars), the red horizontal branch (two stars), and the asymptotic giant branch (eight stars), with effective temperatures ranging from 4000 K to 6100 K. Spectra were obtained with the HIRES spectrometer on the Keck I telescope, with a wavelength coverage from 3700 to 7950 angstroms for the HB and AGB sample, and 5300 to 7600 angstroms for the majority of the RGB sample. We find offsets of some abundance ratios between the AGB and the RGB branches. However, these discrepancies appear to be due to analysis effects, and indicate that caution must be exerted when directly comparing abundance ratios between different evolutionary branches. We find the expected signatures of pollution from material enriched in the products of the hot hydrogen burning cycles such as the CNO, Ne-Na, and Mg-Al cycles, but no significant differences within these signatures among the three stellar evolutionary branches especially when considering the analysis offsets. We are also able to measure an assortment of neutron-capture element abundances, from Sr to Th, in the cluster. We find that the neutron-capture signature for all stars is the same, and shows a predominately r-process origin. However, we also see evidence of a small but consistent extra s-process signature that is not tied to the light-element variations, pointing to a pre-enrichment of this material in the protocluster gas., Comment: 33 pages, 18 figures, accepted for publication in AJ

We present the results of a low-resolution spectral abundance study of 25 stars in the Bootes I dwarf spheroidal (dSph) galaxy. The data were obtained with the LRIS instrument at Keck Observatory, and allow us to measure [Fe/H], [C/Fe], and [alpha/Fe] for each star. We find both a large spread in metallicity (2.1 dex in [Fe/H]) as well as the low average metallicity in this system, <[Fe/H]>=-2.59, matching previous estimates. This sample includes a newly discovered extremely metal-poor star, with [Fe/H]=-3.8, that is one of the most metal-poor stars yet found in a dSph. We compare the metallicity distribution function of Bootes I to analytic chemical evolution models. While the metallicity distribution function of Bootes I is best fit by an Extra Gas chemical evolution model, leaky-box models also provide reasonable fits. We also find that the [alpha/Fe] distribution and the carbon-enhanced metal-poor fraction of our sample (12%) are reasonable matches to Galactic halo star samples in the same metallicity range, indicating that at these low metallicities, systems like the Bootes I ultra-faint dSph could have been contributors to the Galactic halo., Comment: ApJ, accepted. 10 pages, in emulate apj format

We present analysis of high-resolution spectra of a sample of stars in the globular cluster M5 (NGC 5904). The sample includes stars from the red giant branch (seven stars), the red horizontal branch (two stars), and the asymptotic giant branch (eight stars), with effective temperatures ranging from 4000 K to 6100 K. Spectra were obtained with the HIRES spectrometer on the Keck I telescope, with a wavelength coverage from 3700 to 7950 angstroms for the HB and AGB sample, and 5300 to 7600 angstroms for the majority of the RGB sample. We find offsets of some abundance ratios between the AGB and the RGB branches. However, these discrepancies appear to be due to analysis effects, and indicate that caution must be exerted when directly comparing abundance ratios between different evolutionary branches. We find the expected signatures of pollution from material enriched in the products of the hot hydrogen burning cycles such as the CNO, Ne-Na, and Mg-Al cycles, but no significant differences within these signatures among the three stellar evolutionary branches especially when considering the analysis offsets. We are also able to measure an assortment of neutron-capture element abundances, from Sr to Th, in the cluster. We find that the neutron-capture signature for all stars is the same, and shows a predominately r-process origin. However, we also see evidence of a small but consistent extra s-process signature that is not tied to the light-element variations, pointing to a pre-enrichment of this material in the protocluster gas., Comment: 33 pages, 18 figures, accepted for publication in AJ

The final years of the 2000s turned out to be quite eventful for the People's Republic of China (PRC and China interchangeably) and its armed forces, the People's Liberation Army (PLA). While there were exciting events for them to celebrate, there were disturbing ones for them to worry about as well. China's economic reform and phenomenal economic development had sailed on uncharted waters for 30 years. The Chinese Communist Party (CCP) leaders could not have wished for a better occasion than the 2008 Summer Olympics in Beijing to celebrate their accomplishments. The Beijing Olympics ceremonies were probably the most expensive in history; but China had plenty to spend. After all, its economic development had turned it into the world's third largest economy and trading nation, the largest holder of foreign exchange reserves and U.S. treasury bonds, and so on.

We describe a three hour inquiry activity involving converging lenses and telescopes as part of a semester-long astronomy lab course for non-science majors at Hartnell Community College in Salinas, CA. Students were shown several short demonstrations and given the chance to experiment with the materials, after which there was a class discussion about the phenomena they observed. Students worked in groups of 2-4 to design their own experiments to address a particular question of interest to them and then presented their findings to the class. An instructor-led presentation highlighted the students' discoveries and the lab's content goals, followed by a short worksheet-based activity that guided them in applying their new knowledge to build a simple telescope using two converging lenses. The activity was successful in emphasizing communication skills and giving students opportunities to engage in the process of science in different ways. One of the biggest challenges in designing this activity was covering all of the content given the short amount of time available. Future implementations may have more success by splitting the lab into two sessions, one focusing on converging lenses and the other focusing on telescopes., Comment: 11 pages, 3 figures, in ASP Conference Series 436, Learning from Inquiry in Practice, eds. L. Hunter and A. J. Metevier (San Francisco, CA: ASP), 333

We present a method for the determination of [alpha/Fe] ratios from low-resolution (R = 2000) SDSS/SEGUE stellar spectra. By means of a star-by-star comparison with degraded spectra from the ELODIE spectral library and with a set of moderately high-resolution (R = 15,000) and medium-resolution (R = 6000) spectra of SDSS/SEGUE stars, we demonstrate that we are able to measure [alpha/Fe] from SDSS/SEGUE spectra (with S/N > 20/1) to a precision of better than 0.1 dex, for stars with atmospheric parameters in the range Teff = [4500, 7000] K, log g = [1.5, 5.0], and [Fe/H] = [-1.4, +0.3], over the range [alpha/Fe] = [-0.1, +0.6]. For stars with [Fe/H] < -1.4, our method requires spectra with slightly higher signal-to-noise to achieve this precision (S/N > 25/1). Over the full temperature range considered, the lowest metallicity star for which a confident estimate of [alpha/Fe] can be obtained from our approach is [Fe/H] ~ -2.5; preliminary tests indicate that a metallicity limit as low as [Fe/H] ~ -3.0 may apply to cooler stars. As a further validation of this approach, weighted averages of [alpha/Fe] obtained for SEGUE spectra of likely member stars of Galactic globular clusters (M15, M13, and M71) and open clusters (NGC 2420, M67, and NGC 6791) exhibit good agreement with the values of [alpha/Fe] from previous studies. The results of the comparison with NGC 6791 imply that the metallicity range for the method may extend to ~ +0.5., Comment: 47 pages, 11 figures, 5 tables, to appear in AJ

Sharing of services over IP networks prove to be an effective approach to satisfy the demand of network users when their home network cannot offer the required services. Authentication, authorization and revocation are some of the important challenges in the service sharing services over IP networks. This research address the problem associated with the authentication because it becomes more and more complicated due to the incompatible authentication schemes used by individual autonomous networks, privacy of authentication information, and the overhead in establishing the sharing. The case gets worse when a user roams from network to network. Many efforts have been made to address these issues in the past years. Kerberos is a solution for cross realm authentication. Unfortunately, Kerberos suffers from bottle neck and single point of failure. Ad hoc aggregation cannot make use of Kerberos. Eduroam enables sharing of wireless access to users roaming between participating institutions, but only services provided by the home network is available to a user. Mobile Host Routing can route data between mobile user. But the networks are linked together in an unscalable network by network basis. Another authentication scheme which has gained some momentum is OpenID. However, in OpenID, authentication simply means proving the ownership of an account, and there is no binding between the account and the actual user identity. These problems and the limitations in the existing approaches inspired us to propose Service Network Graph, a service authentication infrastructure for service sharing among heterogeneous networks aggregated dynamically via self-authenticating encrypted channels. The key feature of SNG is delegation of authentication authority from one network to another. A user can use the services provided by the delegatee network as well as his home network after authenticating to the delegatee network. When an autonomous network attaches to an SNG, not only does the net

We describe a three hour inquiry activity involving converging lenses and telescopes as part of a semester-long astronomy lab course for non-science majors at Hartnell Community College in Salinas, CA. Students were shown several short demonstrations and given the chance to experiment with the materials, after which there was a class discussion about the phenomena they observed. Students worked in groups of 2-4 to design their own experiments to address a particular question of interest to them and then presented their findings to the class. An instructor-led presentation highlighted the students' discoveries and the lab's content goals, followed by a short worksheet-based activity that guided them in applying their new knowledge to build a simple telescope using two converging lenses. The activity was successful in emphasizing communication skills and giving students opportunities to engage in the process of science in different ways. One of the biggest challenges in designing this activity was covering all of the content given the short amount of time available. Future implementations may have more success by splitting the lab into two sessions, one focusing on converging lenses and the other focusing on telescopes., Comment: 11 pages, 3 figures, in ASP Conference Series 436, Learning from Inquiry in Practice, eds. L. Hunter and A. J. Metevier (San Francisco, CA: ASP), 333

We present a method for the determination of [alpha/Fe] ratios from low-resolution (R = 2000) SDSS/SEGUE stellar spectra. By means of a star-by-star comparison with degraded spectra from the ELODIE spectral library and with a set of moderately high-resolution (R = 15,000) and medium-resolution (R = 6000) spectra of SDSS/SEGUE stars, we demonstrate that we are able to measure [alpha/Fe] from SDSS/SEGUE spectra (with S/N > 20/1) to a precision of better than 0.1 dex, for stars with atmospheric parameters in the range Teff = [4500, 7000] K, log g = [1.5, 5.0], and [Fe/H] = [-1.4, +0.3], over the range [alpha/Fe] = [-0.1, +0.6]. For stars with [Fe/H] < -1.4, our method requires spectra with slightly higher signal-to-noise to achieve this precision (S/N > 25/1). Over the full temperature range considered, the lowest metallicity star for which a confident estimate of [alpha/Fe] can be obtained from our approach is [Fe/H] ~ -2.5; preliminary tests indicate that a metallicity limit as low as [Fe/H] ~ -3.0 may apply to cooler stars. As a further validation of this approach, weighted averages of [alpha/Fe] obtained for SEGUE spectra of likely member stars of Galactic globular clusters (M15, M13, and M71) and open clusters (NGC 2420, M67, and NGC 6791) exhibit good agreement with the values of [alpha/Fe] from previous studies. The results of the comparison with NGC 6791 imply that the metallicity range for the method may extend to ~ +0.5., Comment: 47 pages, 11 figures, 5 tables, to appear in AJ

As the John M. Shalikashvili (Shali) Chair in National Security Studies at The National Bureau of Asian Research (NBR), a role in which I have served since 2007, I participated in the 2008 Carlisle Chinese People's Liberation Army (PLA) conference entitled "PLA Missions beyond Taiwan." Throughout my career and most recently as the Shali Chair, I have spent a great deal of time in China meeting with senior defense officials and discussing the security environment in the region. While U.S.-Sino relations are arguably the best in at least a decade, continued examination of China's security policy is essential in order to anticipate and understand future Chinese military missions within China and on its borders, across the Taiwan Strait, and around the region. On September 26, 2008, over 70 leading experts from academia, government, the military, and policy think tanks assembled at Carlisle Barracks, Pennsylvania, for that very purpose, to look beyond the PLA's primary focus on Taiwan and to the evolving new roles of the PLA. The conference could not have been timelier, given the PLA's active involvement in events during 2008, including earthquake relief, counterterrorism, humanitarian assistance, space activities, and blue water naval operations.

Background and aim of the study Diastolic mitral valve (MV) opening characteristics during ischemic mitral regurgitation (IMR) are poorly characterized. The diastolic MV opening dynamics was quantified along the entire valvular coaptation line in an ovine model of acute IMR. Methods Ten radiopaque markers were sutured in pairs on the anterior (A1-E1) and corresponding posterior (A2-E2) leaflet edges from the anterior (A1/A2) to the posterior (E1/E2) commissure in 11 adult sheep. Immediately after surgery, 4-D marker coordinates were obtained before and during occlusion of the proximal left circumflex coronary artery. Distances between marker pairs were calculated throughout the cardiac cycle every 16.7 ms. Leaflet opening was defined as the time after end-systole (ES) when the first derivative of the distance between marker pairs was greater than a threshold value of 3 cm/s. Valve opening velocity was defined as the maximum slope of marker pair tracings. Results Hemodynamics were consistent with acute ischemia, as reflected by increased MR grade (0.5 ± 0.3 versus 2.3 ± 0.7, p <0.05), decreased contractility (dP/dtmax: 1,948 ± 598 versus 1,119 ± 293 mmHg/s, p <0.05), and slower left ventricular relaxation rate (dP/dtmin: −1,079 ± 188 versus −538 ± 147 mmHg/s, p <0.05). During ischemia, valve opening occurred earlier (A1/A2: 112 ± 28 versus 83 ± 43 ms, B1/B2: 105 ± 32 versus 68 ± 35 ms, C1/C2: 126 ± 25 versus 74 ± 37 ms, D1/D2: 114 ± 28 versus 71 ± 34 ms, E1/E2: 125 ± 29 versus 105 ± 33 ms; all p <0.05) and was slower (A1/A2: 16.8 ± 9.6 versus 14.2 ± 9.4 cm/s, B1/B2: 40.4 ± 9.9 versus 32.2 ± 10.0 cm/s, C1/C2: 59.0 ± 14.9 versus 50.4 ± 18.1 cm/s, D1/D2: 34.4 ± 10.4 versus 25.5 ± 10.9 cm/s; all p <0.05), except at the posterior edge (E1/E2: 13.3 ± 8.7 versus 10.6 ± 7.2 cm/s). The sequence of regional mitral leaflet separation along the line of coaptation did not change with ischemia. Conclusion Acute posterolateral left ventricular ischemia causes earlier

As part of a program to measure abundance ratios in stars beyond 15 kpc from the Galactic center, we have discovered a metal-poor star in the outer halo with a unique chemical signature. We originally identified it in the Sloan Extension for Galactic Understanding and Exploration (SEGUE) survey as a distant metal-poor star. We obtained a follow-up spectrum using the Echellette Spectrograph and Imager (ESI) at the Keck 2 telescope, and measure [Fe/H] =-3.17, [Mg/Fe] =-0.10 and [Ca/Fe] =+1.11. This is one of the largest over-abundances of Ca measured in any star to date; the extremely low value of [Mg/Ca]=-1.21 is entirely unique. To have found such an unusual star in our small sample of 27 targets suggests that there may be previously unobserved classes of stars yet to be found in situ in the Galactic halo., Comment: Accepted by ApJL

The NSF's Astronomy and Astrophysics Postdoctoral Fellowship (AAPF) is exceptional among the available postdoctoral awards in Astronomy and Astrophysics. The fellowship is one of the few that allows postdoctoral researchers to pursue an original research program, of their own design, at the U.S. institution of their choice. However, what makes this fellowship truly unique is the ability of Fellows to lead an equally challenging, original educational program simultaneously. The legacy of this singular fellowship has been to encourage and advance leaders in the field who are equally as passionate about their own research as they are about sharing that research and their passion for astronomy with students and the public. In this positional paper we address the importance of fellowships like the AAPF to the astronomical profession by identifying the science and educational contributions that Fellows have made to the community. Further, we recommend that fellowships that encourage leading postdoctoral researchers to also become leaders in Astronomy education be continued and expanded., Comment: cover page +10 pages, Astro2010 Decadal Survey State of the Profession Position Paper

Background and aim of the study Diastolic mitral valve (MV) opening characteristics during ischemic mitral regurgitation (IMR) are poorly characterized. The diastolic MV opening dynamics was quantified along the entire valvular coaptation line in an ovine model of acute IMR. Methods Ten radiopaque markers were sutured in pairs on the anterior (A1-E1) and corresponding posterior (A2-E2) leaflet edges from the anterior (A1/A2) to the posterior (E1/E2) commissure in 11 adult sheep. Immediately after surgery, 4-D marker coordinates were obtained before and during occlusion of the proximal left circumflex coronary artery. Distances between marker pairs were calculated throughout the cardiac cycle every 16.7 ms. Leaflet opening was defined as the time after end-systole (ES) when the first derivative of the distance between marker pairs was greater than a threshold value of 3 cm/s. Valve opening velocity was defined as the maximum slope of marker pair tracings. Results Hemodynamics were consistent with acute ischemia, as reflected by increased MR grade (0.5 ± 0.3 versus 2.3 ± 0.7, p <0.05), decreased contractility (dP/dtmax: 1,948 ± 598 versus 1,119 ± 293 mmHg/s, p <0.05), and slower left ventricular relaxation rate (dP/dtmin: −1,079 ± 188 versus −538 ± 147 mmHg/s, p <0.05). During ischemia, valve opening occurred earlier (A1/A2: 112 ± 28 versus 83 ± 43 ms, B1/B2: 105 ± 32 versus 68 ± 35 ms, C1/C2: 126 ± 25 versus 74 ± 37 ms, D1/D2: 114 ± 28 versus 71 ± 34 ms, E1/E2: 125 ± 29 versus 105 ± 33 ms; all p <0.05) and was slower (A1/A2: 16.8 ± 9.6 versus 14.2 ± 9.4 cm/s, B1/B2: 40.4 ± 9.9 versus 32.2 ± 10.0 cm/s, C1/C2: 59.0 ± 14.9 versus 50.4 ± 18.1 cm/s, D1/D2: 34.4 ± 10.4 versus 25.5 ± 10.9 cm/s; all p <0.05), except at the posterior edge (E1/E2: 13.3 ± 8.7 versus 10.6 ± 7.2 cm/s). The sequence of regional mitral leaflet separation along the line of coaptation did not change with ischemia. Conclusion Acute posterolateral left ventricular ischemia causes earlier

As part of a program to measure abundance ratios in stars beyond 15 kpc from the Galactic center, we have discovered a metal-poor star in the outer halo with a unique chemical signature. We originally identified it in the Sloan Extension for Galactic Understanding and Exploration (SEGUE) survey as a distant metal-poor star. We obtained a follow-up spectrum using the Echellette Spectrograph and Imager (ESI) at the Keck 2 telescope, and measure [Fe/H] =-3.17, [Mg/Fe] =-0.10 and [Ca/Fe] =+1.11. This is one of the largest over-abundances of Ca measured in any star to date; the extremely low value of [Mg/Ca]=-1.21 is entirely unique. To have found such an unusual star in our small sample of 27 targets suggests that there may be previously unobserved classes of stars yet to be found in situ in the Galactic halo., Comment: Accepted by ApJL

The NSF's Astronomy and Astrophysics Postdoctoral Fellowship (AAPF) is exceptional among the available postdoctoral awards in Astronomy and Astrophysics. The fellowship is one of the few that allows postdoctoral researchers to pursue an original research program, of their own design, at the U.S. institution of their choice. However, what makes this fellowship truly unique is the ability of Fellows to lead an equally challenging, original educational program simultaneously. The legacy of this singular fellowship has been to encourage and advance leaders in the field who are equally as passionate about their own research as they are about sharing that research and their passion for astronomy with students and the public. In this positional paper we address the importance of fellowships like the AAPF to the astronomical profession by identifying the science and educational contributions that Fellows have made to the community. Further, we recommend that fellowships that encourage leading postdoctoral researchers to also become leaders in Astronomy education be continued and expanded., Comment: cover page +10 pages, Astro2010 Decadal Survey State of the Profession Position Paper

We present the results of an abundance analysis for a sample of stars with $-4<$[Fe/H]$<-2$. The data were obtained with the HIRES spectrograph at Keck Observatory. The set includes 28 stars, with effective temperature ranging from 4800 to 6600 K. For 13 stars with [Fe/H]$<-2.6$, including nine with [Fe/H]$<-3.0$ and one with [Fe/H]$=-4.0$, these are the first reported detailed abundances. For the most metal-poor star in our sample, CS 30336-049, we measure an abundance pattern that is very similar to stars in the range [Fe/H]$\sim-3.5$, including a normal C+N abundance. We also find that it has very low but measurable Sr and Ba, indicating some neutron-capture activity even at this low of a metallicity. We explore this issue further by examining other very neutron-capture-deficient stars, and find that at the lowest levels, [Ba/Sr] exhibits the ratio of the main r-process. We also report on a new r-process-enhanced star, CS 31078-018. This star has [Fe/H]$=-2.85$, [Eu/Fe]$=1.23$, and [Ba/Eu]$=-0.51$. CS 31078-018 exhibits an ``actinide boost'', i.e. much higher [Th/Eu] than expected and at a similar level to CS 31082-001. Our spectra allow us to further constrain the abundance scatter at low metallicities, which we then use to fit to the zero-metallicity Type II supernova yields of Heger & Woosley (2008). We find that supernovae with progenitor masses between 10 and 20 M$_{\odot}$ provide the best matches to our abundances., Comment: 48 pages, 30 figures, 17 tables. Updated to ApJ version. Multiple typos and errors fixed

We present the results of an abundance analysis for a sample of stars with $-4<$[Fe/H]$<-2$. The data were obtained with the HIRES spectrograph at Keck Observatory. The set includes 28 stars, with effective temperature ranging from 4800 to 6600 K. For 13 stars with [Fe/H]$<-2.6$, including nine with [Fe/H]$<-3.0$ and one with [Fe/H]$=-4.0$, these are the first reported detailed abundances. For the most metal-poor star in our sample, CS 30336-049, we measure an abundance pattern that is very similar to stars in the range [Fe/H]$\sim-3.5$, including a normal C+N abundance. We also find that it has very low but measurable Sr and Ba, indicating some neutron-capture activity even at this low of a metallicity. We explore this issue further by examining other very neutron-capture-deficient stars, and find that at the lowest levels, [Ba/Sr] exhibits the ratio of the main r-process. We also report on a new r-process-enhanced star, CS 31078-018. This star has [Fe/H]$=-2.85$, [Eu/Fe]$=1.23$, and [Ba/Eu]$=-0.51$. CS 31078-018 exhibits an ``actinide boost'', i.e. much higher [Th/Eu] than expected and at a similar level to CS 31082-001. Our spectra allow us to further constrain the abundance scatter at low metallicities, which we then use to fit to the zero-metallicity Type II supernova yields of Heger & Woosley (2008). We find that supernovae with progenitor masses between 10 and 20 M$_{\odot}$ provide the best matches to our abundances., Comment: 48 pages, 30 figures, 17 tables. Updated to ApJ version. Multiple typos and errors fixed

Background: Improved quantitative understanding of in vivo leaflet geometry in ischemic mitral regurgitation (IMR) is needed to improve reparative techniques, yet few data are available due to current imaging limitations. Using marker technology we tested the hypotheses that IMR (1) occurs chiefly during early systole; (2) affects primarily the valve region contiguous with the myocardial ischemic insult; and (3) results in systolic leaflet edge restriction. Methods: Eleven sheep had radiopaque markers sutured as five opposing pairs along the anterior (A1–E1) and posterior (A2–E2) mitral leaflet free edges from the anterior commissure (A1–A2) to the posterior commissure (E1–E2). Immediately postoperatively, biplane videofluoroscopy was used to obtain 4D marker coordinates before and during acute proximal left circumflex artery occlusion. Regional mitral orifice area (MOA) was calculated in the anterior (Ant-MOA), middle (Mid-MOA), and posterior (Post-MOA) mitral orifice segments during early systole (EarlyS), mid systole (MidS), and end systole (EndS). MOA was normalized to zero (minimum orifice opening) at baseline EndS. Tenting height was the distance of the midpoint of paired markers to the mitral annular plane at EndS. Results: Acute ischemia increased echocardiographic MR grade (0.5 ± 0.3 vs 2.3 ± 0.7, p < 0.01) and MOA in all regions at EarlyS, MidS, and EndS: Ant-MOA (7 ± 10 vs 22 ± 19 mm2, 1 ± 2 vs18 ± 16 mm2, 0 vs 17 ± 15 mm2); Mid-MOA (9 ± 13 vs 25 ± 17 mm2, 3 ± 6 vs 21 ± 19 mm2, 0 vs 25 ± 17 mm2); and Post-MOA (8 ± 10 vs 25 ± 16, 2 ± 4 vs 22 ± 13 mm2, 0 vs 23 ± 13 mm2), all p < 0.05. There was no change in MOA throughout systole (EarlyS vs MidS vs EndS) during baseline conditions or ischemia. Tenting height increased with ischemia near the central and the anterior commissure leaflet edges (B1–B2: 7.1 ± 1.8 mm vs 7.9 ± 1.7 mm, C1–C2: 6.9 ± 1.3 mm vs 8.0 ± 1.5 mm, both p < 0.05). Conclusions: MOA during ischemia was larger throughout systole, indica

We present initial results measuring the companion fraction of metal-poor stars ([Fe/H]$<-$2.0). We are employing the Lick Observatory planet-finding system to make high-precision Doppler observations of these objects. The binary fraction of metal-poor stars provides important constraints on star formation in the early Galaxy (Carney et al. 2003). Although it has been shown that a majority of solar metallicity stars are in binaries, it is not clear if this is the case for metal-poor stars. Is there a metallicity floor below which binary systems do not form or become rare? To test this we are determining binary fractions at metallicities below [Fe/H]$=-2.0$. Our measurments are not as precise as the planet finders', but we are still finding errors of only 50 to 300 m/s, depending on the signal-to-noise of a spectrum and stellar atmosphere of the star. At this precision we can be much more complete than previous studies in our search for stellar companions., Comment: To appear in conference proceedings,"First Stars III", eds. B. O'Shea, A. Heger & T. Abel. 3 pages, 5 figures

We present initial results measuring the companion fraction of metal-poor stars ([Fe/H]$<-$2.0). We are employing the Lick Observatory planet-finding system to make high-precision Doppler observations of these objects. The binary fraction of metal-poor stars provides important constraints on star formation in the early Galaxy (Carney et al. 2003). Although it has been shown that a majority of solar metallicity stars are in binaries, it is not clear if this is the case for metal-poor stars. Is there a metallicity floor below which binary systems do not form or become rare? To test this we are determining binary fractions at metallicities below [Fe/H]$=-2.0$. Our measurments are not as precise as the planet finders', but we are still finding errors of only 50 to 300 m/s, depending on the signal-to-noise of a spectrum and stellar atmosphere of the star. At this precision we can be much more complete than previous studies in our search for stellar companions., Comment: To appear in conference proceedings,"First Stars III", eds. B. O'Shea, A. Heger & T. Abel. 3 pages, 5 figures

We present carbon and strontium abundances for 100 metal-poor stars measured from R$\sim $7000 spectra obtained with the Echellette Spectrograph and Imager at the Keck Observatory. Using spectral synthesis of the G-band region, we have derived carbon abundances for stars ranging from [Fe/H]$=-1.3$ to [Fe/H]$=-3.8$. The formal errors are $\sim 0.2$ dex in [C/Fe]. The strontium abundance in these stars was measured using spectral synthesis of the resonance line at 4215 {\AA}. Using these two abundance measurments along with the barium abundances from our previous study of these stars, we show it is possible to identify neutron-capture-rich stars with our spectra. We find, as in other studies, a large scatter in [C/Fe] below [Fe/H]$ = -2$. Of the stars with [Fe/H]$<-2$, 9$\pm$4% can be classified as carbon-rich metal-poor stars. The Sr and Ba abundances show that three of the carbon-rich stars are neutron-capture-rich, while two have normal Ba and Sr. This fraction of carbon enhanced stars is consistent with other studies that include this metallicity range., Comment: ApJ, Accepted

We present initial results measuring the companion fraction of metal-poor stars ([Fe/H]$<-$2.0). We are employing the Lick Observatory planet-finding system to make high-precision Doppler observations of these objects. The binary fraction of metal-poor stars provides important constraints on star formation in the early Galaxy (Carney et al. 2003). Although it has been shown that a majority of solar metallicity stars are in binaries, it is not clear if this is the case for metal-poor stars. Is there a metallicity floor below which binary systems do not form or become rare? To test this we are determining binary fractions at metallicities below [Fe/H]$=-2.0$. Our measurments are not as precise as the planet finders', but we are still finding errors of only 50 to 300 m/s, depending on the signal-to-noise of a spectrum and stellar atmosphere of the star. At this precision we can be much more complete than previous studies in our search for stellar companions., Comment: To appear in conference proceedings,"First Stars III", eds. B. O'Shea, A. Heger & T. Abel. 3 pages, 5 figures