LLukas22/scidocs huggingface dataset:
Module mismatch loss and recoverable power in unshaded PV installations

Distributed electronics which optimize power in PV systems have the potential to improve energy production even under unshaded conditions. This work investigates the extent to which mismatch in the unshaded electrical characteristics of PV panels causes system-level power losses, which can be recovered in arrays employing power optimizers. Of particular interest is how this potential for power recovery is affected by factors such as available light, cell temperature, panel technology, and field degradation. A system for simultaneous collection of panel-level I-V curves over an entire array is designed. This system is used to acquire high and low light module performance data for a variety of arrays at the National Renewable Energy Laboratory (NREL) test facility. The measured data show moderately low variation in module maximum power and maximum power producing current in all of the arrays. As a group, the tested arrays do not show any strong correlations between this variation and array age, technology type, or operating conditions. The measured data are used to create individual panel performance models for high and low light conditions. These models are then incorporated in annual hourly energy simulations for each array. Annual mismatch loss (and thus potential for increased energy capture using power optimizers) is found to be minimal, <;1 % for all of the sampled arrays. Due to the nature of the tested arrays, these results may or may not be indicative of typical PV array behavior; further investigation is planned over a larger group of PV installations to determine the general applicability of this study's results.
The C Programming Language

In this chapter we will learn how to • write simple computer programs using the C programming language; • perform basic mathematical calculations; • manage data stored in the computer memory and disk; • generate meaningful output on the screen or into a computer file. The C programming language was developed in the early 1970's by Ken Thomp-son and Dennis Ritchie at the Bell Telephone Laboratories. It was designed and implemented in parallel with the operating system Unix and was aimed mostly as a system implementation language [1]. It, nevertheless, evolved into one of the most flexible and widely used computer programming languages today. In 1989, the American National Standards Institute (ANSI) adopted a document that standardized the C language. The particular version of the language that it describes is widely referred to as ANSI C or C89. (ISO) as C90 and was later expanded to the current standard, which is often referred to as C99. The C language consists of a small set of core commands and a large number of library functions that can be incorporated in a program, if necessary. One can find many excellent books that discuss the C language in detail, starting from the first book The C Programming Language by B. [2]. This book describes ANSI C and remains today one of the easiest texts on the subject. In this chapter, we will cover the most basic of the core commands of the language, as well as those library functions that are useful in developing programs that involve scientific computations. 1.1 The first program It is a tradition in the culture of C programming that the first program compiled and executed by a new student of the language is one that prints on the screen the happy message " Hello World! " [2]
Design and control of an air-bearing supported three degree-of-freedom fine positioner

In this paper we discuss design considerations and control issues of a fine-motion device which provides very high performance, precision and speed ( I 2 g’s acceleration, 0.2 pm resolution). Coupled with a standard industrial robot and external sensing, improvements in precision up to two orders of magnitude can be achieved. Software enables it to be operated from a serial port of an IBM PC or PS/2. The moving element of the positioning head can be commanded to move over a + _ I mm range in x and y , and rotated up to f1.75” in e about the z axis. The device provides variable compliance with compliance set by loop gain in a digital controller. It incorporates a novel three degree-offreedom motor, a pair of internal position sensors to enable controlled motion in the plane, and an air bearing to support the moving element.
A five-year analysis of MODIS NDVI and NDWI for grassland drought assessment over the central Great Plains of the United States

[1] A five-year (2001–2005) history of moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) data was analyzed for grassland drought assessment within the central United States, specifically for the Flint Hills of Kansas and Oklahoma. Initial results show strong relationships among NDVI, NDWI, and drought conditions. During the summer over the Tallgrass Prairie National Preserve, the average NDVI and NDWI were consistently lower (NDVI < 0.5 and NDWI < 0.3) under drought conditions than under non-drought conditions (NDVI>0.6 and NDWI>0.4). NDWI values exhibited a quicker response to drought conditions than NDVI. Analysis revealed that combining information from visible, near infrared, and short wave infrared channels improved sensitivity to drought severity. The proposed normalized difference drought index (NDDI) had a stronger response to summer drought conditions than a simple difference between NDVI and NDWI, and is therefore a more sensitive indicator of drought in grasslands than NDVI alone.Citation: Gu, Y., J. F. Brown, J. P. Verdin, and B. Wardlow (2007), A five-year analysis of MODIS NDVI and NDWI for grassland drought assessment over the central Great Plains of the United States, Geophys. Res. Lett., 34, L06407, doi:10.1029/ 2006GL029127.
Effect of time of day on walking capacity and self-reported fatigue in persons with multiple sclerosis: a multi-center trial.

BACKGROUND
Many persons with multiple sclerosis (PwMS) report increased fatigue in the afternoon and evening compared with the morning. It is commonly accepted that physical capacity also decreases as time of day progresses, potentially influencing the outcomes of testing.


OBJECTIVE
The objective of this article was to determine whether self-reported fatigue level and walking capacity are influenced by time of day in PwMS.


METHODS
A total of 102 PwMS from 8 centers in 5 countries, with a diverse level of ambulatory dysfunction (Expanded Disability Status Scale [EDSS] <6.5), participated. Patients performed walking capacity tests and reported fatigue level at three different time points (morning, noon, afternoon) during 1 day. Walking capacity was measured with the 6-Minute Walk Test (6MWT) and the 10-m walk test performed at usual and fastest speed. Self-reported fatigue was measured by the Rochester Fatigue Diary (RFD). Subgroups with mild (EDSS 1.5-4.0, n = 53) and moderate (EDSS 4.5-6.5, n = 49) ambulatory dysfunction were formed, as changes during the day were hypothesized to depend on disability status.


RESULTS
Subgroups had different degree of ambulatory dysfunction (p < 0.001) but reported similar fatigue levels. Although RFD scores were affected by time of day with significant differences between morning and noon/afternoon (p < 0.0001), no changes in walking capacity were found in any subgroup. Additional analyses on subgroups distinguished by diurnal change in self-reported fatigue failed to reveal analogous changes in walking capacity.


CONCLUSIONS
Testing of walking capacity is unaffected by time of day, despite changes in subjective fatigue.
Ideological Segregation and the Effects of Social Media on News Consumption

Scholars have argued that online social networks and personalized web search increase ideological segregation. We investigate the impact of these potentially polarizing channels on news consumption by examining web browsing histories for 50,000 U.S.-located users who regularly read online news. We find that individuals indeed exhibit substantially higher segregation when reading articles shared on social networks or returned by search engines, a pattern driven by opinion pieces. However, these polarizing articles from social media and web search constitute only 2% of news consumption. Consequently, while recent technological changes do increase ideological segregation, the magnitude of the effect is limited. JEL: D83, L86, L82
ANN-based fault classification and location in MVDC shipboard power systems

Uninterrupted power supply is an important requirement for electric ship since it has to confront frequent travel and hostilities. However, the occurrence of faults in the shipboard power systems interrupts the power service continuity and leads to the severe damage on the electrical equipments. Faults need to be quickly detected and isolated in order to restore the power supply and prevent the massive cascading outage effect on the electrical equipments. Proper protective actions are needed to be implemented to ensure smooth and continuous operation of electric ship. This paper proposes an Artificial Neural Network (ANN) based method for the fault classification and location in the MVDC shipboard power systems using the transient information in the fault voltage and current waveforms. The proposed approach is applied to the cable of an equivalent MVDC system which is simulated using PSCAD. It is found to be efficient in detecting the type and location of the DC cable faults.
Active Grammatical Inference: A New Learning Methodology

In this paper a new methodology for inferring regular grammars y from a set of positive and negative examples and a-priori knowledge (if available), that we have called active grammatical inference, is presented. The methodology is based on a combination of neural and symbolic techniques, with the interesting feature that the learning process can be guided by the validated previous results and/or by introducing constraints or (positive/negative) rules dynamically. This is possible thanks to a new neural learning scheme, in which the inserted symbolic knowledge, that is also preserved, controls the learning mechanism. The whole process is conceived as a sequence of learning cycles, each one including the steps of FSA insertion, neural training, FSA extraction, symbolic manipulation and validation. The insertion of symbolic information into a recurrent neural network is carried out through linear system solving. An example which allows to compare the active grammatical inference methodology with just the neural or symbolic approaches is also included.
Step-up therapy for children with uncontrolled asthma receiving inhaled corticosteroids.

BACKGROUND
For children who have uncontrolled asthma despite the use of low-dose inhaled corticosteroids (ICS), evidence to guide step-up therapy is lacking.


METHODS
We randomly assigned 182 children (6 to 17 years of age), who had uncontrolled asthma while receiving 100 microg of fluticasone twice daily, to receive each of three blinded step-up therapies in random order for 16 weeks: 250 microg of fluticasone twice daily (ICS step-up), 100 microg of fluticasone plus 50 microg of a long-acting beta-agonist twice daily (LABA step-up), or 100 microg of fluticasone twice daily plus 5 or 10 mg of a leukotriene-receptor antagonist daily (LTRA step-up). We used a triple-crossover design and a composite of three outcomes (exacerbations, asthma-control days, and the forced expiratory volume in 1 second) to determine whether the frequency of a differential response to the step-up regimens was more than 25%.


RESULTS
A differential response occurred in 161 of 165 patients who were evaluated (P<0.001). The response to LABA step-up therapy was most likely to be the best response, as compared with responses to LTRA step-up (relative probability, 1.6; 95% confidence interval [CI], 1.1 to 2.3; P=0.004) and ICS step-up (relative probability, 1.7; 95% CI, 1.2 to 2.4; P=0.002). Higher scores on the Asthma Control Test before randomization (indicating better control at baseline) predicted a better response to LABA step-up (P=0.009). White race predicted a better response to LABA step-up, whereas black patients were least likely to have a best response to LTRA step-up (P=0.005).


CONCLUSIONS
Nearly all the children had a differential response to each step-up therapy. LABA step-up was significantly more likely to provide the best response than either ICS or LTRA step-up. However, many children had a best response to ICS or LTRA step-up therapy, highlighting the need to regularly monitor and appropriately adjust each child's asthma therapy. (ClinicalTrials.gov number, NCT00395304.)
Five-times-sit-to-stand test in children with cerebral palsy: reliability and concurrent validity.

BACKGROUND/PURPOSE
Five-times-sit-to-stand test (FTSST) is a reliable tool for measuring lower limb functional strength and balance ability. However, reports of the reliability of FTSST in children with cerebral palsy have been scarce. The purposes of this study were (1) to investigate the test-retest and inter-rater reliability of the FTSST and (2) to investigate the correlation between the FTSST and standard functional balance tests in children with cerebral palsy.


STUDY DESIGN
Cross-sectional study.


MATERIALS AND METHODS
Thirty-three school children aged from 6 to 18 years with Gross motor functional classification system expanded and revised version (GMFCS-E&R) level I to III were recruited. Reliability of the FTSST and concurrent validity between FTSST and Timed up and go test (TUG) and Berg balance scale (BBS) were determined using the Pearson product moment correlation.


RESULTS
The intra-class correlation coefficient (ICC) for test-retest and inter-rater reliability of FTSST were 0.91 and 0.88 respectively. FTSST showed moderate correlation with TUG (r = 0.552, P < 0.01) and with BBS (r = -0.561, P < 0.01).


CONCLUSION
FTSST is a reliable assessment tool and correlates with functional balance ability tests in children with mild to moderate cerebral palsy.
Social capital, knowledge management, and sustained superior performance

Purpose – This article attempts to begin the process of removing the cloak of causal ambiguity by examining the role that knowledge management has in the creation of the wide variety of competitive advantages found in some organizations. Specifically, this article aims to extend understanding in the field of knowledge management by examining how knowledge management can affect organizational performance, and by examining one possible determinant of an organization’s capacity to manage knowledge. Design/methodology/approach – Reviews literature on resources-advantage theory of the firm, social capital and knowledge management to propose ways within the organization to improve their ability to manage knowledge and achieve sustained superior performance. The paper is structured around the following constructs: resource-advantage theory of the firm, social capital, and knowledge management. Findings – Describes the relationship between social capital and knowledge management and how both help organizations achieve a sustained superior performance within the market. Suggests that organizations with high levels of social capital have more knowledge-management capabilities than organizations with low levels of social capital. Research limitations/implications – This article extends prior research of knowledge management by proposing how social capital can positively impact the ability of organizations to manage knowledge. Practical implications – Since resources within all businesses are relatively limited, and particularly so when the business is small relative to its competitors, the revelation that social capital can lead to more effective knowledge management makes the decision to support and nurture social-capital development much more credible. Originality/value – Because there is no existing literature that has examined the relationship between social capital, knowledge management, and organizational performance, this paper provides a foundation for future studies that examine the relationship between social capital and knowledge management.
Temporal lobe asymmetry in patients with Alzheimer's disease with delusions.

OBJECTIVE
To test the hypothesis that delusions are associated with asymmetric involvement of the temporal lobe regions in Alzheimer's disease.


METHODS
Temporal lobe atrophy was assessed with a linear measure of width of the temporal horn (WTH) taken from CT films. Temporal asymmetry was computed as the right/left (R/L) ratio of the WTH in 22 non-delusional and 19 delusional patients with Alzheimer's disease. Delusional patients had paranoid delusions (of theft, jealousy, persecution). None of the patients had misidentifications or other delusions of non-paranoid content.


RESULTS
The R/L ratio indicated symmetric temporal horn size in the non-delusional (mean 1. 05 (SD 0.20), and right greater than left temporal horn in the delusional patients (mean 1.30, (SD 0.46); t=2.27, df=39, p=0.03). When patients were stratified into three groups according to the R/L ratio, 47% of the delusional (9/19) and 14% of the non-delusional patients (3/21; chi(2)=5.6, df=1, p=0.02) showed right markedly greater than left WTH.


CONCLUSIONS
Predominantly right involvement of the medial temporal lobe might be a determinant of paranoid delusions in the mild stages of Alzheimer's disease.
Fulfilling Papert's Dream: Computational Fluency for All

Fifty years ago, Seymour Papert and colleagues developed Logo as the first programming language for children. Today, millions of children are participating in learn-to-code initiatives, but Papert's dream remains unfulfilled. Papert (who passed away last summer) saw programming not as a set of technical skills but as a new form of fluency - a new way for all children to explore, experiment, and express themselves. In this presentation, I will examine strategies for fulfilling Papert's dream. Drawing on examples from our Scratch online coding community, I will discuss how we can design programming environments and activities to help all children, from all backgrounds, to develop their thinking, develop their voices, and develop their identities.
Basic Properties of the Blockchain: (Invited Talk)

As the first decentralized cryptocurrency, Bitcoin [1] has ignited much excitement, not only for its novel realization of a central bank-free financial instrument, but also as an alternative approach to classical distributed computing problems, such as reaching agreement distributedly in the presence of misbehaving parties, as well as to numerous other applications-contracts, reputation systems, name services, etc. The soundness and security of these applications, however, hinges on the thorough understanding of the fundamental properties of its underlying blockchain data structure, which parties ("miners") maintain and try to extend by generating "proofs of work" (POW, aka "cryptographic puzzle"). In this talk we follow the approach introduced in [2], formulating such fundamental properties of the blockchain, and then showing how applications such as consensus and a robust public transaction ledger can be built ``on top'' of them. The properties are as follows, assuming the adversary's hashing power (our analysis holds against arbitrary attacks) is strictly less than ½ and high network synchrony:
 Common prefix: The blockchains maintained by the honest parties possess a large common prefix. More specifically, if two honest parties "prune" (i.e., cut off) k blocks from the end of their local chains, the probability that the resulting pruned chains will not be mutual prefixes of each other drops exponentially in the that parameter.
 Chain quality: We show a bound on the ratio of blocks in the chain of any honest party contributed by malicious parties. In particular, as the adversary's hashing power approaches ½, we show that blockchains are only guaranteed to have few, but still some, blocks contributed by honest parties.
 Chain growth: We quantify the number of blocks that are added to the blockchain during any given number of rounds during the execution of the protocol. (N.B.: This property, which in [2] was proven and used directly in the form of a lemma, was explicitly introduced in [3]. Identifying it as a separate property enables modular proofs of applications' properties.)
 The above properties hold assuming that all parties-honest and adversarial-"wake up" and start computing at the same time, or, alternatively, that they compute on a common random string (the "genesis" block) only made available at the exact time when the protocol execution is to begin. In this talk we also consider the question of whether such a trusted setup/behavioral assumption is necessary, answering it in the negative by presenting a Bitcoin-like blockchain protocol that is provably secure without trusted setup, and, further, overcomes such lack in a scalable way-i.e., with running time independent of the number of parties [4].
 A direct consequence of our construction above is that consensus can be solved directly by a blockchain protocol without trusted setup assuming an honest majority (in terms of computational power).
Brief report: If you build it, they will come

BACKGROUND: Latinos have low representation in cancer prevention trials and intervention studies. Culturally appropriate recruitment strategies are needed to address this issue. OBJECTIVE: To describe and summarize the effectiveness of recruitment strategies used by the Latin American Cancer Research Coalition (LACRC). DESIGN: Descriptive report of recruitment methods. PARTICIPANTS: Uninsured Latino immigrants (N=1,170; 77% female, 23% male) from Central and South America recruited to 7 cancer control studies. APPROACH: The LACRC recruitment model involved inclusion of Latino researchers and providers, and use of culturally acceptable materials released through culturally appropriate outlets such as Latino radio stations. RESULTS: The overall participation rate was high—96% of patients identified as eligible agreed to participate. Women were excellent referrals for recruiting men to research studies. Additionally, a local Latino radio program was used to efficiently recruit eligible study participants. CONCLUSIONS: Latinos are interested and willing to participate in cancer control studies when culturally relevant approaches are used. Research teams that partner with Latino researchers and with Latino service providers are important in educating Latinos about cancer control and encouraging participation in research.
Towards Procedural Quest Generation : A Structural Analysis of RPG Quests

An analysis of several role playing games indicates that player quests share common elements, and that these quests may be abstractly represented using a small expressive language. One benefit of this representation is that it can guide procedural content generation by allowing quests to be generated using this abstraction, and then later converting them into a concrete form within a game’s domain.