LLukas22/scidocs huggingface dataset:
Aalborg Universitet A Survey on Control of Electric Power Distributed Generation Systems for Microgrid Applications

The introduction of microgrids in distribution networks based on power electronics facilitates the use of renewable energy resources, distributed generation (DG) and storage systems while improving the quality of electric power and reducing losses thus increasing the performance and reliability of the electrical system, opens new horizons for microgrid applications integrated into electrical power systems. The hierarchical control structure consists of primary, secondary, and tertiary levels for microgrids that mimic the behavior of the mains grid is reviewed. The main objective of this paper is to give a description of state of the art for the distributed power generation systems (DPGS) based on renewable energy and explores the power converter connected in parallel to the grid which are distinguished by their contribution to the formation of the grid voltage and frequency and are accordingly classified in three classes. This analysis is extended focusing mainly on the three classes of configurations grid-forming, grid-feeding, and gridsupporting. The paper ends up with an overview and a discussion of the control structures and strategies to control distribution power generation system (DPGS) units connected to the network. Keywords— Distributed power generation system (DPGS); hierarchical control; grid-forming; grid-feeding; grid-supporting. Nomenclature Symbols id − iq Vd − Vq P Q ω E f U
Vaginal breech delivery: results of a prospective registration study

BACKGROUND
Most countries recommend planned cesarean section in breech deliveries, which is considered safer than vaginal delivery. As one of few countries in the western world Norway has continued to practice planned vaginal delivery in selected women. The aim of this study is to evaluate prospectively registered neonatal and maternal outcomes in term singleton breech deliveries in a Norwegian hospital during a ten years period. We aim to compare maternal and neonatal outcomes in term breech pregnancies subjected either to planned vaginal or elective cesarean section.


METHODS
A prospective registration study including 568 women with term breech deliveries (>37 weeks) consecutively registered at Sorlandet Hospital Kristiansand between 2001 and 2011. Fetal and maternal outcomes were compared according to delivery method; planned vaginal delivery versus planned cesarean section.


RESULTS
Of 568 women, elective cesarean section was planned in 279 (49%) cases and vaginal delivery was planned in 289 (51%) cases. Acute cesarean section was performed in 104 of the planned vaginal deliveries (36.3%). There were no neonatal deaths. Two cases of serious neonatal morbidity were reported in the planned vaginal group. One infant had seizures, brachial plexus injury, and cephalhematoma. The other infant had 5-minutes Apgar < 4. Twenty-nine in the planned vaginal group (10.0%) and eight in the planned cesarean section group (2.9%) (p < 0.001) were transferred to the neonatal intensive care unit. However, only one infant was admitted for ≥4 days. According to follow-up data (median six years) none of these infants had long-term sequelae. Regarding maternal morbidity, blood loss was the only variable that was significantly higher in the planned cesarean section group versus in the vaginal delivery group (p < 0.001).


CONCLUSIONS
Strict guidelines were followed in all cases. There were no neonatal deaths. Two infants had serious neonatal morbidity in the planned vaginal group without long-term sequelae.
Private education as a policy tool in Turkey

This paper discusses privatisation as policy tool to solve educational problems in Turkey. Turkey, as a developing country, is faced with many problems in education. Large class size, low enrolment rate, girl’s education, high illiteracy rate, religious education, textbooks, curriculum and multicultural education are some of the important problems. On the other hand, cultural diversity, economical problems and lack of resources, migration, central management, the rapid growth in school-age population and regional differences make the solution difficult. In principle, privatisation could help in the solution of the problems in Turkey. Private schools can increase the quality of education. Private schools can share responsibility with the government by investing money in education. In addition, private schools can also meet the needs for diversity in society promoting specific religious or philosophical views by using their own teaching methods. The paper describes the availability of private schooling in Ankara as a baseline for thinking about the development of private schooling in Turkey.
Ischemic preconditioning suppresses ventricular tachyarrhythmias after myocardial revascularization.

BACKGROUND
Ventricular fibrillation (VF) and tachycardia (VT) are the common and potential life-threatening complications after CABG. Ischemic preconditioning (IP) has been proved effective in reducing ischemia reperfusion arrhythmia in animals and humans. Whether IP is effective in suppressing postoperative VF/VT in patients with CABG has not been studied.


METHODS AND RESULTS
Eighty-six patients with CABG with stable and unstable 3-vessel disease were equally randomly assigned into an IP and a control group. The patients who received IP received 2 periods of 2-minute ischemia followed by 3-minute reperfusion. Twenty-four-hour electrocardiographic data were collected. IP resulted in fewer cases of VF after declamping (48.8% versus 79.1% in IP and control, P=0.004) and a shorter VF period (2.28+/-0.44 versus 4.41+/-0.51 minutes, P=0.002). The episodes of VT were significantly reduced in patients in the IP group during early reperfusion and 24 hours after reperfusion (0.65+/-0.16 versus 3.71+/-0.46, P=0.000 and 0.07+/-0.04 versus 2.12+/-1.41, P=0.002, respectively). De novo sustained VT occurred in 3 control patients as against none in the IP group after surgery. As a result, IP significantly curtailed the mechanical ventilation period and reduced the need for inotropes.


CONCLUSIONS
IP significantly reduced postoperative VF/VT in patients with CABG with 3-vessel disease. Suppression of VT during early reperfusion and 24 hours after reperfusion suggests early and delayed IP phenomena in patients undergoing CABG surgery.
On risk, convenience, and Internet shopping behavior

The past century experienced a proliferation of retail formats in the marketplace. However, as a new century begins, these retail formats are being threatened by the emergence of a new kind of store, the online or Internet store. From being almost a novelty in 1995, online retailing sales were expected to reach $7 billion by 2000 [9]. In this increasngly timeconstrained world, Internet stores allow consumers to shop from the convenience of remote locations. Yet most of these Internet stores are losing money [6]. Why is such counterintuitive phenomena prevailing? The explanation may lie in the risks associated with Internet shopping. These risks may arise because consumers are concerned about the security of transmitting credit card information over the Internet. Consumers may also be apprehensive about buying something without touching or feeling it and being unable to return it if it fails to meet their approval. Having said this, however, we must point out that consumers are buying goods on the Internet. This is reflected in the fact that total sales on the Internet are on the increase [8, 11]. Who are the consumers that are patronizing the Internet? Evidently, for them the perception of the risk associated with shopping on the Internet is low or is overshadowed by its relative convenience. This article attempts to determine why certain consumers are drawn to the Internet and why others are not. Since the pioneering research done by Becker [3], it has been accepted that the consumer maximizes his utility subject to not only income constraints but also time constraints. A consumer seeks out his best decision given that he has a limited budget of time and money. While purchasing a product from a store, a consumer has to expend both money and time. Therefore, the consumer patronizes the retail store where his total costs or the money and time spent in the entire process are the least. Since the util-
Algorithmic and Complexity Results for Decompositions of Biological Networks into Monotone Subsystems

A useful approach to the mathematical analysis of large-scale biological networks is based upon their decompositions into monotone dynamical systems. This paper deals with two computational problems associated to finding decompositions which are optimal in an appropriate sense. In graph-theoretic language, the problems can be recast in terms of maximal sign-consistent subgraphs. The theoretical results include polynomial-time approximation algorithms as well as constant-ratio inapproximability results. One of the algorithms, which has a worst-case guarantee of 87.9% from optimality, is based on the semidefinite programming relaxation approach of Goemans-Williamson [Goemans, M., Williamson, D., 1995. Improved approximation algorithms for maximum cut and satisfiability problems using semidefinite programming. J. ACM 42 (6), 1115-1145]. The algorithm was implemented and tested on a Drosophila segmentation network and an Epidermal Growth Factor Receptor pathway model, and it was found to perform close to optimally.
Modern Antenna Handbook [Reviews and Abstracts]

This new handbook is an efficient way to keep up with the continuing advances in antenna technology and applications. The handbook is uniformly well written, up-to-date, and filled with a wealth of practical information. This makes it a useful reference for most antenna engineers and graduate students.
Null Controllability of Some Systems of Two Parabolic Equations with One Control Force

In this paper we establish some exact controllability results for systems of two parabolic equations. In a first part, we prove the existence of insensitizing controls for the L norm of the gradient of solutions of linear heat equations. Then, in the worst situation where null controllability for a system of two parabolic equations can hold, we prove this result for some general couplings. MSC: 35K40, 93B05
Modelling and smoothing parameter estimation with multiple quadratic penalties

Penalized likelihood methods provide a range of practical modelling tools, including spline smoothing, generalized additive models and variants of ridge regression. Selecting the correct weights for penalties is a critical part of using these methods and in the single penalty case the analyst has several well founded techniques to choose from. However, many modelling problems suggest a formulation employing multiple penalties, and here general methodology is lacking. A wide family of models with multiple penalties can be fitted to data by iterative solution of the generalized ridge regression problem: minimise ‖W(Xp− y)‖ρ + ∑m i=1 θip Sip (p is a parameter vector, X a design matrix, Si a non-negative definite coefficient matrix defining the i penalty with associated smoothing parameter θi, W a diagonal weight matrix, y a vector of data or pseudodata and ρ an ‘overall’ smoothing parameter included for reasons of computational efficiency). This paper shows how smoothing parameter selection can be performed efficiently by applying generalized cross validation to this problem and how this allows non-linear, generalized linear and linear models to be fitted using multiple penalties, substantially increasing the scope of penalized modelling methods. Examples of non-linear modelling, generalized additive modelling and anisotropic smoothing are given.
Combat deployment is associated with sexual harassment or sexual assault in a large, female military cohort.

BACKGROUND
Previous studies have examined the prevalence, risk factors, and health correlates of sexual stressors in the military, but have been limited to specific subpopulations. Furthermore, little is known about sexual stressors' occurrence and their correlates in relation to female troops deployed to the current operations in Iraq and Afghanistan.


METHODS
Using longitudinal data from Millennium Cohort participants, the associations of recent deployment as well as other individual and environmental factors with sexual harassment and sexual assault were assessed among U.S. female military personnel. Multivariable analyses were used to investigate the associations.


FINDINGS
Of 13,262 eligible participants, 1,362 (10.3%) reported at least one sexual stressor at follow-up. Women who deployed and reported combat experiences were significantly more likely to report sexual harassment (odds ratio [OR], 2.20; 95% confidence interval [CI], 1.84-2.64) or both sexual harassment and sexual assault (OR, 2.47; 95% CI, 1.61-3.78) compared with nondeployers. In addition, significant risk factors for sexual stressors included younger age, recent separation or divorce, service in the Marine Corps, positive screen for a baseline mental health condition, moderate/severe life stress, and prior sexual stressor experiences.


CONCLUSIONS
Although deployment itself was not associated with sexual stressors, women who both deployed and reported combat were at a significantly increased odds for sexual stressors than other female service members who did not deploy. Understanding the factors associated with sexual stressors can inform future policy and prevention efforts to eliminate sexual stressors.
LATIONS FOR KNOWLEDGE BASE COMPLETION

In this work we present a novel approach for the utilization of observed relations between entity pairs in the task of triple argument prediction. The approach is based on representing observations in a shared, continuous vector space of structured relations and text. Results on a recent benchmark dataset demonstrate that the new model is superior to existing sparse feature models. In combination with state-of-the-art models, we achieve substantial improvements when observed relations are available.
Prepubertal gynecomastia: indirect exposure to estrogen cream.

OBJECTIVE
To describe the clinical course of 3 prepubertal boys who presented with gynecomastia resulting from indirect exposure to a custom-compounded preparation of estrogen cream used by each child's mother.


METHODOLOGY
Each child was initially referred to the Children's Medical Center of Dallas' Endocrinology Center and followed for over 1 year.


RESULTS
All 3 boys presented with gynecomastia and elevated estradiol levels. Two had accelerated growth and advanced bone ages. Within 4 months after each child's mother discontinued use of the topical estrogen preparation, each child's gynecomastia regressed and estradiol levels returned to normal.


CONCLUSION
Indirect exposure to excessive amounts of topical estrogen may cause gynecomastia, rapid changes in growth, and advanced bone age in prepubertal children. Because custom-compounded topical estrogen preparations are not regulated by the Food and Drug Administration and may contain high concentrations of estrogen, we recommend that women requiring estrogen use an alternate form of estrogen delivery if they are in frequent close contact with children.
Education, ethics and e-Communication in medicine

The article attempts to introduce an ethical approach of communication aspects with respect to the use of Internet and its influence on University Transilvania of Brasov medical students. The profound changes of medical ethics in the informatics society are well known. Although ethics is an ancient concern of humanity it cannot ignore the present times’ developments in technology and science, including computer science, and especially today when eHealth benefits from e-mail, chat rooms, online discussion group, forums, blogs or instant messaging. Obvious the students feel these communication paths’ influence so designing and developing a subject as ethics in communication and e-Health became very important in the education of medical students and in the future education of computer sciences and medical engineering students.
Predicting remaining useful life of an individual unit using proportional hazards model and logistic regression model

Reliability of an individual unit during field use is important in many critical applications such as turbine engines, life-maintaining systems and civil engineering structures. The remaining useful life (RUL) of the unit indicates its ability of surviving the operation in the future. When the failure indication (degradation) has been detected, it is essential to estimate the RUL accurately for making a timely maintenance decision for failure avoidance. In recent years, RUL prediction in service has received increasing attention. As many powerful sensors and signal processing techniques appear, multiple degradation features can be extracted for degradation detection and quantification. These features can serve as the basis for RUL prediction. This paper presents the proportional hazards model and logistic regression model, which relates the multiple degradation features of sensor signals to the specific reliability indices of the unit, and enable us to predict its RUL. Comparisons are made for the two models regarding their effectiveness and computation effort. An example of bearing test is provided to demonstrate the proposed approach in practical use. The results show that the models are capable of providing accurate RUL prediction to support timely maintenance decisions
Tiled convolutional neural networks

[1] Y. LeCun, L. Bottou, Y. Bengio, and P. Haffner. Gradient based learning applied to document recognition. Proceeding of the IEEE, 1998. [2] H. Lee, R. Grosse, R. Ranganath, and A.Y. Ng. Convolutional deep belief networks for scalable unsupervised learning of hierarchical representations. In ICML, 2009. [3] M.A. Ranzato, K. Jarrett, K. Kavukcuoglu and Y. LeCun. What is the best multi-stage architecture for object recognition? In ICCV, 2009. [4] A. Hyvarinen and P. Hoyer. Topographic independent component analysis as a model of V1 organization and receptive fields. Neural Computation, 2001. [5] A. Hyvarinen, J. Hurri, and P. Hoyer. Natural Image Statistics. Springer, 2009. [6] K. Kavukcuoglu, M. Ranzato, R. Fergus, Y. LeCun. Learning invariant features through topographic filter maps . In CVPR, 2009. [7] K. Gregor, Y. LeCun. Emergence of Complex-Like Cells in a Temporal Product Network with Local Receptive Fields. ARXIV, 2010.
Framework for Agile Methods Classification

Agile methods are the response to turbulent software development environments and requirements definitions differs in these methods from what is done in others. The purpose of this paper is to classify these former methods to measure their impact on requirement engineering processes. The approach used in this research has several purposes, the first one is to build a framework to classify and compare the methods. The second is to propose a component based approach to bring agility
Robust linear optimization under general norms

We propose a framework for robust modeling of linear programming problems using uncertainty sets described by an arbitrary norm. We explicitly characterize the robust counterpart as a convex optimization problem that involves the dual norm of the given norm. Under a Euclidean norm we recover the second order cone formulation in BenTal and Nemirovski [1, 2], El Ghaoui et al. [8, 9], while under a particular D-norm we introduce we recover the linear programming formulation proposed in Bertsimas and Sim [6]. We also provide guarantees for constraint violation under general probabilistic models that allow arbitrary dependencies in the distribution of the uncertain coefficients.
Effects of modified sit-to-stand training on balance control in hemiplegic stroke patients: a randomized controlled trial.

OBJECTIVE
To explore the effectiveness of modified sit-to-stand training on balance function in hemiplegic stroke patients.


DESIGN
Randomized controlled trial.


SETTING
Rehabilitation medical centre.


PARTICIPANTS
A total of 50 hemiplegic patients with stroke were randomly assigned to the control and experimental groups (n = 25 for each group).


INTERVENTIONS
Patients in the control group received the sit-to-stand training with symmetrical foot position, while patients in the experimental group were given the modified sit-to-stand training in which the paretic foot placed posterior. Subjects in both groups received 30 minutes of sit-to-stand training, five times a week, for four weeks.


MAIN OUTCOME MEASURES
The time and weight-bearing distribution during sit-to-stand movement, the centre of pressure sway length during quiet standing, the centre of pressure sway areas during dynamic standing and Berg Balance Scale were assessed before and after completing the four-week sit-to-stand training.


RESULTS
Our data showed significant improvements in standing balance and the sit-to-stand movement for two groups in the post-training compared with the pre-training. After training, the rise time shortened more significantly in the experimental group (mean change, 0.90 ±0.25 seconds) than the control group (mean change, 0.42 ±0.18 seconds). Weight-bearing asymmetry showed significantly greater improvement in the experimental group (mean change, 0.17 ±0.10) than in the control group (mean change, 0.06 ±0.05). Centre of pressure sway length was significantly smaller in the experimental group (mean change, 27.85 ±10.58 cm) than in the control group (mean change, 21.95 ±8.19 cm). Centre of pressure sway areas was significantly larger in the experimental group (mean change, 84.24 ±26.48 cm(2)) than in the control group (mean change, 67.74 ±22.84 cm(2)) (P = 0.027). The Berg Balance Scale was significantly higher in the experiment group (mean change, 8.4 ±3.1) than the control group (mean change, 5.8±2.8).


CONCLUSIONS
A modified sit-to-stand training improves the balance function in hemiplegic stroke patients.