bluuebunny/crossref_metadata_2025_split huggingface dataset:
A New Method to Estimate Risk and Return of Nontraded Assets from Cash Flows: The Case of Private Equity Funds
Authors: Driessen Joost , Lin Tse-Chun , Phalippou Ludovic 
Published: April 2012

AbstractWe develop a new methodology to estimate abnormal performance and risk exposure of nontraded assets from cash flows. Our methodology extends the standard internal rate of return approach to a dynamic setting. The small-sample properties are validated using a simulation study. We apply the method to a sample of 958 private equity funds. For venture capital funds, we find a high market beta and underperformance before and after fees. For buyout funds, we find a relatively low market beta and no evidence for outperformance. We find that self-reported net asset values significantly overstate fund values for mature and inactive funds.
Position-singularity analysis of a special class of the Stewart parallel mechanisms with two dissimilar semi-symmetrical hexagons
Authors: Li Baokun , Cao Yi , Zhang Qiuju , Huang Zhen 
Published: April 2012

SUMMARYIn this paper, for a special class of the Stewart parallel mechanism, whose moving platform and base one are two dissimilar semi-symmetrical hexagons, the position-singularity of the mechanism for a constant-orientation is analyzed systematically. The force Jacobian matrix [J]T is constructed based on the principle of static equilibrium and the screw theory. After expanding the determinant of the simplified matrix [D], whose rank is the same as the rank of the matrix [J]T, a cubic symbolic expression that represents the 3D position-singularity locus of the mechanism for a constant-orientation is derived and graphically represented. Further research shows that the 3D position-singularity surface is extremely complicated, and the geometric characteristics of the position-singularity locus lying in a general oblique plane are very difficult to be identified. However, the position-singularity locus lying in the series of characteristic planes, where the moving platform coincides, are all quadratic curves compromised of infinite many sets of hyperbolas, four pairs of intersecting lines and a parabola. For some special orientations, the quadratic curve can degenerate into two lines or even one line, all of which are parallel to the ridgeline. Two theorems are presented and proved for the first time when the geometric characteristics of the position-singularity curves in the characteristic plane are analyzed. Moreover, the kinematic property of the position-singularity curves is obtained using the Grassmann line geometry and the screw theory. The theoretical results are demonstrated with several numeric examples.
Robot force control without dynamic model: theory and experiments
Authors: Rivera-Dueñas Juan C. , Arteaga-Pérez Marco A. 
Published: April 2012

SUMMARYAmong the many challenges to deal with, when a robot is interacting with its environment, friction at the contact surface and/or at the joints is one of the most important to be considered. In this paper we propose a control algorithm for the tracking of position and force (unconstrained orientation case only) of a manipulator end-effector that does not require the robot model for implementation. This characteristic has the advantage of making it capable to compensate friction effects without any previous estimation. Furthermore, no velocity measurements are needed, and the unit quaternion is employed for orientation control. Experimental and simulation results are provided.
On the terminology and geometric aspects of redundant parallel manipulators
Authors: Müller Andreas 
Published: April 2012

SUMMARYParallel kinematics machines (PKMs) can exhibit kinematics as well as actuation redundancy. While the meaning of kinematic redundancy has been already clarified for serial manipulators, actuation redundancy, which is only possible in PKMs, is differently classified in the literature. In this paper a consistent terminology for general redundant PKM is proposed. A kinematic model is introduced with the configuration space (c-space) as central part. The notion of kinematic redundancy is recalled for PKM. C-space, output, and input singularities are distinguished. The significance of the c-space geometry is emphasized, and it is pointed out geometrically that input singularities can be avoided by redundant actuation schemes. In order to distinguish different actuation schemes of PKM, a nonlinear control system is introduced whose dynamics evolves on c-space. The degree of actuation (DOA) is introduced as the number of independent control vector fields, and PKMs are classified as full-actuated and underactuated machines. Relating this DOA to degree of freedom allows to classify the actuation redundancy.
From Slavery to Freedom: Abolitionist Expressions in Maskilic Sea Adventures
Authors: Wolpe Rebecca 
Published: April 2012

“Black” themes held a substantial place in twentieth-century American Yiddish poetry and prose, as well as in Yiddish journalism. As Hasia Diner notes in her work on Jews and blacks in the United States in the twentieth century, Jews sympathized with the plight of American blacks and their fight for civil rights. However, this had not always been the case, as evidenced by the many staunch Jewish supporters of slavery and Jewish slave owners and traders. Jonathan Schorsch claims that “under the sign of theHaskala…little changed” in this respect. In discussing a reference by Isaac Satanov to black slavery, Schorsch notes:One cannot gauge from this brief comment whether Satanov knew about the abolitionist movements beginning to agitate in England and France at the time. Satanov's reportage was remarkably non-committal, betraying little, if any, sympathy for these developments.
Variations in functional decomposition for an existing product: Experimental results
Authors: Eckert Claudia , Ruckpaul Anne , Alink Thomas , Albers Albert 
Published: April 2012

AbstractThis paper describes the findings of an experiment on how different engineers understand notions of function and functional breakdown in the context of design by modification. The experiment was conducted with a homogenous group of 20 design engineers, who had all received the same education. The subjects were asked to analyze how a hydraulic pump works and summarize their understanding in a function tree. The subjects were given either the hydraulic pump itself (with part of its casing removed) or a maintenance drawing that showed a section cut of the pump. This paper shows typical outputs of the designers. It discusses the different notions of function that the subjects had and the differences in the function trees they generated. The paper focuses an eight detailed analyses to show the range of approaches the subjects took.
Hierarchical structuring of layout problems in an interactive evolutionary layout system
Authors: Koenig Reinhard , Schneider Sven 
Published: April 2012

AbstractThis paper focuses on computer-based generative methods for layout problems in architecture and urban planning with special regard for the hierarchical structuring of layout elements. The generation of layouts takes place using evolutionary algorithms, which are used to optimize the arrangement of elements in terms of overlapping within a given boundary and the topological relations between them. In this paper, the approach is extended by a data structure that facilitates the hierarchical organization of layout elements making it possible to structure and organize larger layout problems into subsets that can be solved in parallel. An important aspect for the applicability of such a system in the design process is an appropriate means of user interaction. This depends largely on the calculation speed of the system and the variety of viable solutions. These properties are evaluated for hierarchical as well as for nonhierarchical structured layout problems.
A computational approach to biologically inspired design
Authors: Nagel Jacquelyn K.S. , Stone Robert B. 
Published: April 2012

AbstractThe natural world provides numerous cases for analogy and inspiration in engineering design. During the early stages of design, particularly during concept generation when several variants are created, biological systems can be used to inspire innovative solutions to a design problem. However, identifying and presenting the valuable knowledge from the biological domain to an engineering designer during concept generation is currently a somewhat disorganized process or requires extensive knowledge of the biological system. To circumvent the knowledge requirement problem, we developed a computational approach for discovering biological inspiration during the early stages of design that integrates with established function-based design methods. This research defines and formalizes the information identification and knowledge transfer processes that enable systematic development of biologically inspired designs. The framework that supports our computational design approach is provided along with an example of a smart flooring device to demonstrate the approach. Biologically inspired conceptual designs are presented and validated through a literature search and comparison to existing products.
Habitat use and circadian pattern of Solitary Tinamou Tinamus solitarius in a southern Brazilian Atlantic rainforest
Authors: KUHNEN VANESSA V. , DE LIMA R. E. M. , SANTOS J. F. , MACHADO FILHO L. C. P. 
Published: April 2012

SummarySolitary Tinamou Tinamus solitarius is a threatened Brazilian bird, and very little is known about its ecology and behaviour. In this study we aimed to verify the use of habitats in different stages of plant succession and the circadian activity pattern of the species. The study was conducted in Santa Catarina state (27º43’S, 48º49’W). Six camera traps were used to record the species in three areas of different successional stages during a 12-month period. Traps remained at each sample site for two months, after which they were moved to a new site, a minimum distance of 100 m apart. A total of 76 independent records of Solitary Tinamou were obtained, and its habitat use was found to be different within the three successional stages (P = 0.02). The majority of 54 independent records were obtained in the secondary forest; not one photo of the species was taken in the most degraded area. Solitary Tinamou exhibited a crepuscular pattern of activity, with most records (n = 38) taken at 07h00 and 06h00, and it appears to be sensitive to forest clearance.
Celebrating the End of School Life: A Pilot Study
Authors: Hutton Alison , Roderick Allison , Munt Rebecca , Mayner Lidia , Kako Mayumi , Arbon Paul 
Published: April 2012

AbstractIntroduction: Celebrating the end of secondary schooling (“Schoolies Festival”) is an established part of the school culture in Australia, with thousands of young students converging at beachside locations to celebrate this rite of passage. The aim of this study was to identify what young people believe is important to remain safe and healthy at this mass-gathering event.Methods: This study was conducted using postcard surveys requesting demographic data and responses to the questions: (1) What do you think is important to stay safe and healthy at this event?; (2) What do you think is risky attending this event?; (3) Which of these is most likely to affect you at this event?; and (4) Where would you seek medical support? The surveys were distributed to attendees of a “Schoolies Festival” in Adelaide, Australia in 2008.Results: One hundred sixty-five of the 300 postcards were returned completed. The average age of the respondents was 17.7 years. “Not using drugs” was considered important to staying safe and healthy by 120 (73%) of respondents; “drinking alcohol responsibly” was considered important by 89 (54%); and “violent behavior” and “exposure to illicit drugs” were identified as important risks by 135 (82%) and 98 (59%) of participants, respectively. Only 35 (21%) of respondents indicated that they would seek on-site health care if needed.Conclusion: Young people attending mass-gathering celebrations have valid concerns about drinking responsibly, exposure to illicit drugs, and sexual harassment. Health messages or health promotion strategies aimed at their specific concerns would be helpful in the mitigation of illness or injury at such events.
Increasing Emergency Medicine Residents’ Confidence in Disaster Management: Use of an Emergency Department Simulator and an Expedited Curriculum
Authors: Franc Jeffrey Michael , Nichols Darren , Dong Sandy L. 
Published: April 2012

AbstractIntroduction: Disaster Medicine is an increasingly important part of medicine. Emergency Medicine residency programs have very high curriculum commitments, and adding Disaster Medicine training to this busy schedule can be difficult. Development of a short Disaster Medicine curriculum that is effective and enjoyable for the participants may be a valuable addition to Emergency Medicine residency training.Methods: A simulation-based curriculum was developed. The curriculum included four group exercises in which the participants developed a disaster plan for a simulated hospital. This was followed by a disaster simulation using the Disastermed.Ca Emergency Disaster Simulator computer software Version 3.5.2 (Disastermed.Ca, Edmonton, Alberta, Canada) and the disaster plan developed by the participants. Progress was assessed by a pre- and post-test, resident evaluations, faculty evaluation of Command and Control, and markers obtained from the Disastermed.Ca software.Results: Twenty-five residents agreed to partake in the training curriculum. Seventeen completed the simulation. There was no statistically significant difference in pre- and post-test scores. Residents indicated that they felt the curriculum had been useful, and judged it to be preferable to a didactic curriculum. In addition, the residents’ confidence in their ability to manage a disaster increased on both a personal and and a departmental level.Conclusions: A simulation-based model of Disaster Medicine training, requiring approximately eight hours of classroom time, was judged by Emergency Medicine residents to be a valuable component of their medical training, and increased their confidence in personal and departmental disaster management capabilities.
Prehospital Trauma System Reduces Mortality in Severe Trauma: A Controlled Study of Road Traffic Casualties in Iraq
Authors: Murad Mudhafar Karim , Issa Dara B. , Mustafa Farhad M. , Hassan Hlwa O. , Husum Hans 
Published: April 2012

AbstractIntroduction: In low-resource communities with long prehospital transport times, most trauma deaths occur outside the hospital. Previous studies from Iraq demonstrate that a two-tier network of rural paramedics with village-based first helpers reduces mortality in land mine and war-injured from 40% to 10%. However, these studies of prehospital trauma care in low-income countries have been conducted with historical controls, thus the results may be unreliable due to differences in study contexts. The aim of this study was to use a controlled study design to examine the effect of a two-tier prehospital rural trauma system on road traffic accident trauma mortality.Methods: A single referral surgical hospital was the endpoint in a single-blinded, non-randomized cohort study. The catchment areas consisted of some districts with no formal Emergency Medical Services (EMS) system, and other districts where 95 health center paramedics had been trained and equipped to provide advanced life support, and 5,000 laypersons had been trained to give on-site first aid. The hospital staff registered trauma mortality and on-admission physiological severity blindly. Assuming that prehospital care would have no significant impact on mortality in moderate injuries, only road traffic accident (RTA) casualties with an Injury Severity Score (ISS) ≥9 were selected for study.Results: During a three-month study period, 205 patients were selected for study (128 in the treatment group and 77 in the control group). The mean prehospital transit time was approximately two hours. The two groups were comparable with regards to demographic characteristics, distribution of wounds and injuries, and mean anatomical severity. The mortality rate was eight percent in the treatment group, compared to 44% in the control group (95% CI, 25%–48%). Adjusted for severity differences between the treatment and control groups, prehospital care was a significant contributor to survival.Conclusion: Where prehospital transport time is long, a two-tier prehospital system of trained paramedics and layperson first responders reduces trauma mortality in severe RTA injuries. The findings may be valid for civilian Emergency Medical Services interventions in other low-resource countries.
Incidence of Tension Pneumothorax in Police Officers Feloniously Killed in the Line of Duty: A Ten-Year Retrospective Analysis
Authors: Mark Ashley C. , Wimberger Nicole , Sztajnkrycer Matthew D. 
Published: April 2012

AbstractBackground: According to US military data, tension pneumothorax (TPx) is the second leading cause of possibly preventable combat death after isolated extremity hemorrhage. The purpose of this study was to determine whether TPx similarly represents a significant cause of possibly preventable death in police officers.Methods: FBI data for the years 1998 through 2007 were reviewed. Cases were included if officers were on-duty at the time of fatal injury, and died within one hour from time of wounding from penetrating torso trauma. After case identification, letters were sent to the departments of victim officers requesting autopsy reports.Results: One hundred and eight victim officers met inclusion criteria. Four charts were excluded due to inability to re-identify officers. Departmental response rate was 83.7%. Autopsy reports were provided for 60 officers (57.7%). All officers died from gunshot wounds. No coroner specifically identified TPx as either a direct cause of death or a contributing factor (95% CI, 0.00%-5.96%).Conclusion: In contrast to the military experience, TPx appears to be a rare cause of possibly preventable death in police officers. Further study of non-fatal “near miss” events will be required to determine the actual need for law enforcement-specific medical training in the recognition and management of TPx.
Assessing the Psychosocial Elements of Crowds at Mass Gatherings
Authors: Hutton Alison , Zeitz Kathryn , Brown Steve , Arbon Paul 
Published: April 2012

AbstractIntroduction: The environmental aspects of mass gatherings that can affect the health and safety of the crowd have been well described. Although it has been recognized that the nature of the crowd will directly impact the health and safety of the crowd, the majority of research focuses on crowd behavior in a negative context such as violence or conflict. Within the mass gathering literature, there is no agreement on what crowd behavior, crowd mood and crowd type actually mean. At the same time, these elements have a number of applications, including event management and mass gathering medicine. These questions are worthy of exploration.Methods: This paper will report on a pilot project undertaken to evaluate how effective current crowd assessment tools are in understanding the psychosocial domain of a mass gathering event.Results: The pilot project highlighted the need for a more consistent descriptive data set that focuses on crowd behavior.Conclusions: The descriptive data collected in this study provide a beginning insight into the science of understanding crowds at a mass gathering event. This pilot has commenced a process of quantifying the psychosocial nature of an event. To maximize the value of this work, future research is required to understand the interplay among the three domains of mass gatherings (physical, environmental and psychological), along with the effects of each element within the domains on safety and health outcomes for participants at mass gatherings.
Balancing Between Closeness and Distance: Emergency Medical Services Personnel’s Experiences of Caring for Families at Out-of-Hospital Cardiac Arrest and Sudden Death
Authors: Bremer Anders , Dahlberg Karin , Sandman Lars 
Published: April 2012

AbstractIntroduction:Out-of-hospital cardiac arrest (OHCA) is a lethal health problem that affects between 236,000 and 325,000 people in the United States each year. As resuscitation attempts are unsuccessful in 70-98% of OHCA cases, Emergency Medical Services (EMS) personnel often face the needs of bereaved family members.Problem:Decisions to continue or terminate resuscitation at OHCA are influenced by factors other than patient clinical characteristics, such as EMS personnel’s knowledge, attitudes, and beliefs regarding family emotional preparedness. However, there is little research exploring how EMS personnel care for bereaved family members, or how they are affected by family dynamics and the emotional contexts. The aim of this study is to analyze EMS personnel’s experiences of caring for families when patients suffer cardiac arrest and sudden death.Methods:The study is based on a hermeneutic lifeworld approach. Qualitative interviews were conducted with 10 EMS personnel from an EMS agency in southern Sweden.Results:The EMS personnel interviewed felt responsible for both patient care and family care, and sometimes failed to prioritize these responsibilities as a result of their own perceptions, feelings and reactions. Moving from patient care to family care implied a movement from well-structured guidance to a situational response, where the personnel were forced to balance between interpretive reasoning and a more direct emotional response, at their own discretion. With such affective responses in decision-making, the personnel risked erroneous conclusions and care relationships with elements of dishonesty, misguided benevolence and false hopes. The ability to recognize and respond to people’s existential questions and needs was essential. It was dependent on the EMS personnel’s balance between closeness and distance, and on their courage in facing the emotional expressions of the families, as well as the personnel’s own vulnerability. The presence of family members placed great demands on mobility (moving from patient care to family care) in the decision-making process, invoking a need for ethical competence.Conclusion:Ethical caring competence is needed in the care of bereaved family members to avoid additional suffering. Opportunities to reflect on these situations within a framework of care ethics, continuous moral education, and clinical ethics training are needed. Support in dealing with personal discomfort and clear guidelines on family support could benefit EMS personnel.