nils-herrmann/clean_scirepeval huggingface dataset:
Zipporah: a Fast and Scalable Data Cleaning System for Noisy Web Crawled Parallel Corpora
Venue: EMNLP
Year: 2017

We introduce Zipporah, a fast and scalable data cleaning system. We propose a novel type of bag of words translation feature, and train logistic regression models to classify good data and synthetic noisy data in the proposed feature space. The trained model is used to score parallel sentences in the data pool for selection. As shown in experiments, Zipporah selects a high quality parallel corpus from a large, mixed quality data pool. In particular, for one noisy dataset, Zipporah achieves a 2.1 BLEU score improvement with using 1/5 of the data over using the entire corpus.
Frontiers of Mid IR Lasers Based on Transition Metal Doped Chalcogenides
Venue: IEEE Journal of Selected Topics in Quantum Electronics
Year: 2018

Enabling broad tunability, high peak and average power, ultrashort pulse duration, and all known modes of laser operation transition metal (TM) doped II VI chalcogenides are the materials of choice for direct lasing in the mid IR. The host materials feature broad infrared transparency, high thermal conductivity, low phonon cutoff, low optical losses, and are available as either single crystals or polycrystalline ceramics. Doped with TM ions, these media exhibit a four level energy structure, the absence of excited state absorption, as well as broad absorption and emission bands. Doped single crystals of high optical quality are difficult to grow; however, the advent of postgrowth diffusion doped ceramics has resulted in significant progress in laser development. Here, we summarize recent experimental laser results on Cr and Fe doped II VI chalcogenides providing access to the 1.8 6 mm spectral range with a high >60% efficiency, multi Watt level [140 W in continuous wave (CW) output powers, tunability of >1000 nm, short pulse <16 fs) multi Watt oscillation, and multi Joule output energies in free running and gain switched regimes. We also review recent results on hybrid fiber bulk (Er fiber/Er:YAG, Tm fiber: Ho:YAG/YLF) systems combining high efficiency of CW fiber lasers with high pulse energies of bulk materials and serving as pump sources of gain switched Cr:II VI lasers.
Object oriented high resolution remote sensing image classification method
Year: 2012

The invention provides an object oriented high resolution remote sensing image classification method. The method comprises the steps of S1, conducting segmentation processing on images to be processed to obtained a plurality of subimage objects; S2, obtaining feature information of subimage objects; and S3, classifying subimage objects according to the obtained feature information, wherein images to be processed are high resolution remote sensing images, the feature information of subimage objects comprises spectral information, shape information and texture information of subimage objects. According to the method, on the basis of object oriented classification, a classification method combining probabilistic latent semantic analysis and a support vector machine is introduced, the problem that 'the same features with different classifications' and 'the same classifications with different features' are not high in identification ratio in the prior art is solved, the classification precision of high resolution remote sensing images is greatly improved, advantages of latent semantic analysis (LSA) and advantages of probabilistic latent semantic analysis (PLSA) are combined, and the problems of overfitting and local optimum which are caused by random initialization are effectively solved.
AMSI Based Detection of Malicious PowerShell Code Using Contextual Embeddings
Venue: AsiaCCS
Year: 2020

PowerShell is a command line shell, supporting a scripting language. It is widely used in organizations for configuration management and task automation but is also increasingly used for launching cyber attacks against organizations, mainly because it is pre installed on Windows machines and exposes strong functionality that may be leveraged by attackers. This makes the problem of detecting malicious PowerShell code both urgent and challenging. Microsoft's Antimalware Scan Interface (AMSI) built into Windows 10, allows defending systems to scan all the code passed to scripting engines such as PowerShell prior to its execution. In this work, we conduct the first study of malicious PowerShell code detection using the information made available by AMSI. We present several novel deep learning based detectors of malicious PowerShell code that employ pretrained contextual embeddings of words from the PowerShell "language" A contextual word embedding is able to project semantically similar words to proximate vectors in the embedding space. A known problem in the cybersecurity domain is that labeled data is relatively scarce, in comparison with unlabeled data, making it difficult to devise effective supervised detection of malicious activity of many types. This is also the case with PowerShell code. Our work shows that this problem can be mitigated by learning a pretrained contextual embedding based on unlabeled data. We trained and evaluated our models using real world data, collected using AMSI. The contextual embedding was learnt using a large corpus of unlabeled PowerShell scripts and modules collected from public repositories. Our performance analysis establishes that the use of unlabeled data for the embedding significantly improved the performance of our detectors. Our best performing model uses an architecture that enables the processing of textual signals from both the character and token levels and obtains a true positive rate of nearly 90% while maintaining a low false positive rate of less than 0.1%
Is Real time Phishing Eliminated with FIDO? Social Engineering Downgrade Attacks against FIDO Protocols
Venue: IACR Cryptol. ePrint Arch.
Year: 2020

FIDO's Universal 2 Factor (U2F) is a web authentication mechanism designed to provide resilience to real time phishing a class of attacks that undermines multi factor authentication by allowing an attacker to relay second factor onetime tokens from the victim user to the legitimate website in real time. A U2F dongle is simple to use, and is designed to ensure users have complete mental models of proper usage. We show that social engineering attacks allow an adversary to downgrade FIDO's U2F to alternative authentication mechanisms. Websites allow such alternatives to handle dongle malfunction or loss. All FIDO supporting wesbites in Alexa's top 100 allow choosing alternatives to FIDO, and are thus vulnerable to real time phishing attacks. We crafted a phishing website that mimics Google login's page and implements a FIDO downgrade attack. We then ran a carefully designed user study to test the effect on users. We found that, while registering FIDO as their second authentication factor, 55 of participants fell for real time phishing, and another 35% would potentially be susceptible to the attack in practice.
Performance analysis of a passive cooling system equipped with a new designed solar chimney and a water spraying system in an underground channel
Venue: Sustainable Energy Technologies and Assessments
Year: 2019

A large portion of electricity use in the residential and commercial sectors is for space conditioning. Reducing the energy use for space conditioning is also important in order to develop energy efficient buildings. Therefore, this paper dealt mainly with analyzing the performance of a new passive solar cooling system in air conditioning of a room under arid climate by means of computational fluid dynamics (CFD) method. The passive cooling system consisted of a solar chimney with four tilted absorbers, faced symmetrically towards south north direction, and a wet underground channel. The cooling effect of the wet underground channel was replicated using water spraying system (WSS) model. The results revealed that the new design of the solar chimney could create a desirable natural air conditioning in the room during the daytime without risk of temperature stratification in the occupancy zone. Applying WSS in the room air intakes satisfied the thermal comfort requirements by decreasing the average indoor temperature around 7 13 degC. Furthermore, it improved the temperature effectiveness of the passive solar system by, at least, 80% implying a uniform diffusion of supply air in the zone of occupancy.
Contraintes, Potentialites Et Opportunites Sociales Et Economiques De La Filiere Anacarde (Cote d'Ivoire)
Venue: European Scientific Journal ESJ
Year: 2019

Depuis quelques decennies, le Nord de la Cote d'Ivoire est confronte a une dynamique de precarisation sociale et economique du fait de nombreux parametres (crises sociopolitiques, changement climatique, secheresses, volatilite des prix agricoles etc. Cependant, l'une des opportunites socioeconomiques qui est la filiere anacarde se trouve confrontee a des mutations particulieres portees par la crise socio politique qu'a connue le pays. Dans un tel contexte de vulnerabilite ou le systeme de commercialisation interieure presente de nombreuses contraintes, une demarche a ete proposee dans cette etude. Il s'agissait de comprendre et d'expliquer les changements induits par le delitement de la filiere anacarde pendant la crise socio politique, tout en identifiant les contraintes, les potentialites et les opportunites. L'etude repose sur des notes d'observations participantes, des entretiens semi structures, des enquetes et une revue documentaire. Ainsi, les crises sociopolitiques de 2002 et postelectorale de 2010 ont fait intervenir de nouveaux acteurs, de nouvelles zones d'ombres dans la filiere anacarde. Face a ces modifications, les producteurs et les acheteurs se sont adaptes par la mise en place de strategies. In recent decades, the north of Cote d'Ivoire has been confronted with a dynamic of social and economic precariousness due to many parameters (socio political crises, climate change, droughts, volatility of agricultural prices etc. However, one of the socio economic opportunities that is the cashew industry is facing particular changes brought by the socio political crisis in the country. In such a context of vulnerability where the internal marketing system presents many constraints, an approach has been proposed in this study. The aim was to understand and explain the changes brought about by the disintegration of the cashew nut sector during the socio political crisis, while identifying constraints, potentialities and opportunities. The study is based on participant observation notes, semi structured interviews, surveys and a literature review. Thus, the socio political crises of 2002 and postelection of 2010 brought in new actors, new areas of shadow in the cashew nut sector. In the face of these changes, producers and buyers have adapted by putting strategies in place.
The Effect of Husbandry and Management System on Sudan Desert Sheep Leather Production and Quality
Year: 2019

This trail is aimed to demonstrate the effect of husbandry and management system on Sudan desert sheep performance and skin quality. For this purpose a questionnaire was designed and distributed randomly for 20 sheep breeders in each of the five chosen sheep breed area's (Total of 100 ques. The questionnaire include beside the personal data, twenty two (22) questions mainly about; system of feeding and application methods in each season, husbandry systems in each season, the main effective treatments on skins quality and common skin diseases and external parasites. The results revealed that, most of Sudan desert sheep owners or breeders were illiterate and most of them were herder 48.0% while 37.5% were herder and farmer at the same time. All respondents confirmed that the open system depending on natural grazing was the main husbandry and management system in all study target area. In autumn sheep depends totally on natural pasture grazing, while in winter sheep partly fed on natural grazing and the breeders complete it's feeding depending on the litter that remained from food crops after harvesting. Sudan desert sheep breeder in summer are using their stock of forage hay that collected either during the rainy season from good growing autumn pastures or from agricultural byproducts such as sorghum and sesame straw or groundnut residuals. The additional diets is varies by the variation of Sudan desert sheep locations. sometimes when forage are limited and for marketing purposes Sudan desert sheep breeders adding little amount or uncountable amount of sorghum grains, cotton seed cakes, groundnut seed cake as finisher diet concentrate beside agricultural byproducts such as groundnut byproduct hay, sorghum byproduct hay and sesame byproduct hay for the herd that offered for sale or for fleshing or steaming up ewes during lambing season. Branding is the most common and known damage in skins generally. Also some animal breeder's belief that by means of hot iron branding some animals may acquire immunity against certain diseases. The respondents attributed causes of mechanical damages of skins of animals on range land mainly to the domination of thorny bushes and grass with hairy and spiny seeds in pastures. External parasites and skin diseases cause most of skins damages and wastages in Sudan generally. Sheep pox spreads on sheep skins with high rates (88% On the other hand, mange are resulting in (8% of Research Article
Long noncoding RNA LBX2 AS1 modulated miR 4766 5p regulates gastric cancer development through targeting CXCL5
Venue: Cancer cell international
Year: 2020

Long noncoding RNAs (LncRNAs) have been reported to critically regulate gastric cancer (GC) Recently, it was reported that LBX2 antisense RNA 1 (LBX2 AS1) is abnormally expressed in GC. However, the role of LBX2 AS1 in the malignancy of GC is worth further discussion.  Quantitative real time polymerase chain reaction (qRT PCR) was used to determine the LBX2 AS1, miR 4766 5p and C X C motif chemokine (CXCL5) expression in GC tissues and cells. Dual luciferase reporter assay was applied to examine the target relationship between LBX2 AS1 and miR 4766 5p or miR 4766 5p and CXCL5. Cell counting kit 8 (CCK 8) and Transwell assays were used to detect cell proliferation, migration and invasion rates. The protein expression of CXCL5 was confirmed using western blot. The RNA pull down experiment was used to verify the specificity of LBX2 AS1 and miR 4766 5p on BGC 823 and SGC 7901 cells. Results LBX2 AS1 was up regulated in GC tissues and cells, and its knockdown suppressed proliferation, migration and invasion of GC cells. While, overexpression of LBX2 AS1 increased proliferation and increased CXCL5 mRNA level. CXCL5 improved cell proliferation, migration and invasion of GC cells. LBX2 AS1 could bind to miR 4766 5p to regulate CXCL5 expression. Overexpression of CXCL5 overturned those effects of miR 4766 5p in GC cells. RNA Pull down shown that BGC 823 and SGC 7901 cells, miR 4766 5p specifically binds to LBX2 AS1.  In short, this study demonstrated that LBX2 AS1 promoted proliferation, migration and invasion through up regulation CXCL5 mediated by miR 4766 5p in GC. The LBX2 AS1/miR 4766 5p/CXCL5 regulatory axis provides a theoretical basis for the research on lncRNA directed therapeutics in GC.
Inferring Adaptive Goal Directed Behavior Within Recurrent Neural Networks
Venue: ICANN
Year: 2017

This paper shows that active inference based, flexible, adaptive goal directed behavior can be generated by utilizing temporal gradients in a recurrent neural network (RNN) The RNN learns a dynamical sensorimotor forward model of a partially observable environment. It then uses this model to execute goal directed policy inference online. The internal neural activities encode the predictive state of the controlled entity. The active inference process projects these activities into the future via the RNN's recurrences, following a tentative sequence of motor commands. This sequence is adapted by back projecting error between the forward projected hypothetical states and the desired goal states onto the motor commands. As an example, we show that a trained RNN model can be used to precisely control a multi copter like system. Moreover, we show that the RNN can plan hundreds of time steps ahead, unfolding non linear imaginary paths around obstacles.
Human Risk on Heavy Metal Pollution and Bioaccumulation Factor in Soil and Some Edible Vegetables around Active Auto Mechanic Workshop in Chanchaga Minna Niger State, Nigeria
Year: 2020

Soil samples are an excellent media to monitor the concentration of heavy metal pollution because anthropogenic heavy metals are usually deposited in the soils. Plants planted on a land polluted with engine oil can absorb heavy metals through their roots. These absorbed metals get accumulated in the roots, stems, fruits, buds, grains and leaves of these plants. Heavy metals gradually accumulate in the soil, and its stability will cause accumulation and pollution since they could not be decomposed or are not biodegradable, like other organic pollutants through biological or chemical processes. Leafy vegetables are the major sources of micronutrients (vitamins, mineral elements) antioxidants and other photochemical required for the maintenance of good health and prevention of degenerative diseases. They also contain dietary fibers for bowel movement which helps in the reduction of blood cholesterol levels and may lower the risk of
Maximum Likelihood Constraint Inference for Inverse Reinforcement Learning
Venue: ICLR
Year: 2020

While most approaches to the problem of Inverse Reinforcement Learning (IRL) focus on estimating a reward function that best explains an expert agent's policy or demonstrated behavior on a control task, it is often the case that such behavior is more succinctly represented by a simple reward combined with a set of hard constraints. In this setting, the agent is attempting to maximize cumulative rewards subject to these given constraints on their behavior. We reformulate the problem of IRL on Markov Decision Processes (MDPs) such that, given a nominal model of the environment and a nominal reward function, we seek to estimate state, action, and feature constraints in the environment that motivate an agent's behavior. Our approach is based on the Maximum Entropy IRL framework, which allows us to reason about the likelihood of an expert agent's demonstrations given our knowledge of an MDP. Using our method, we can infer which constraints can be added to the MDP to most increase the likelihood of observing these demonstrations. We present an algorithm which iteratively infers the Maximum Likelihood Constraint to best explain observed behavior, and we evaluate its efficacy using both simulated behavior and recorded data of humans navigating around an obstacle.
Ultra Low Power Event Driven Wireless Sensor Node Using Piezoelectric Accelerometer for Health Monitoring
Year: 2009

We describe a low power consumption wireless sensor node designed for monitoring the conditions of animals, especially of chickens. The node detects variations in 24 h behavior patterns by acquiring the number of the movement of an animal whose acceleration exceeds a threshold measured in per unit time. Wireless sensor nodes when operated intermittently are likely to miss necessary data during their sleep mode state and waste the power in the case of acquiring useless data. We design the node worked only when required acceleration is detected using a piezoelectric accelerometer and a comparator for wake up source of micro controller unit.
Reconciling the Impossible South Africa s Government of National Unity In 1994
Year: 2017

In 1994, Nelson Mandela's African National Congress bridged distrust among rivals in the National Party and the Inkatha Freedom Party to form a Government of National Unity. The new government initiated social programs designed to improve access to education, housing, and other services, and facilitated development of a new constitution to replace the country's apartheid era legal system. These achievements were possible because of procedural innovations as well as exceptional leadership. Although the National Party withdrew from the arrangement in 1996, the unity government fostered cross party collaboration and laid the framework for an inclusive and democratic South Africa. The model developed became a reference point for negotiators and leaders in other parts of the world.
Learning Policies for Markov Decision Processes From Data
Venue: IEEE Transactions on Automatic Control
Year: 2019

We consider the problem of learning a policy for a Markov decision process consistent with data captured on the state action pairs followed by the policy. We parameterize the policy using features associated with the state action pairs. The features can be handcrafted or defined using kernel functions in a reproducing kernel Hilbert space. In either case, the set of features can be large and only a small, unknown subset may need to be used to fit a specific policy to the data. The parameters of such a policy are recovered using <inline formula><tex math notation="LaTeX"\ell _1$/tex math>/inline formula> regularized logistic regression. We establish bounds on the difference between the average reward of the estimated and the unknown original policies (regret) in terms of the generalization error and the ergodic coefficient of the underlying Markov chain. To that end, we combine sample complexity theory and sensitivity analysis of the stationary distribution of Markov chains. Our analysis suggests that to achieve regret within order <inline formula><tex math notation="LaTeX"$O(\sqrt{\epsilon /tex math>/inline formula> it suffices to use training sample size of the order of <inline formula><tex math notation="LaTeX"\Omega \log n \cdot \text{poly}(1/\epsilon)/tex math>/inline formula> where <inline formula><tex math notation="LaTeX"$n$/tex math>/inline formula> is the number of the features. We demonstrate the effectiveness of our method on a synthetic robot navigation example.
Sphingolipid based drugs selectively kill cancer cells by down regulating nutrient transporter proteins.
Venue: The Biochemical journal
Year: 2011

Cancer cells are hypersensitive to nutrient limitation because oncogenes constitutively drive glycolytic and TCA (tricarboxylic acid) cycle intermediates into biosynthetic pathways. As the anaplerotic reactions that replace these intermediates are fueled by imported nutrients, the cancer cell's ability to generate ATP becomes compromised under nutrient limiting conditions. In addition, most cancer cells have defects in autophagy, the catabolic process that provides nutrients from internal sources when external nutrients are unavailable. Normal cells, in contrast, can adapt to the nutrient stress that kills cancer cells by becoming quiescent and catabolic. In the present study we show that FTY720, a water soluble sphingolipid drug that is effective in many animal cancer models, selectively starves cancer cells to death by down regulating nutrient transporter proteins. Consistent with a bioenergetic mechanism of action, FTY720 induced homoeostatic autophagy. Cells were protected from FTY720 by cell permeant nutrients or by reducing nutrient demand, but blocking apoptosis was ineffective. Importantly, AAL 149, a FTY720 analogue that lacks FTY720's dose limiting toxicity, also triggered transporter loss and killed patient derived leukaemias while sparing cells isolated from normal donors. As they target the metabolic profile of cancer cells rather than specific oncogenic mutations, FTY720 analogues such as AAL 149 should be effective against many different tumour types, particularly in combination with drugs that inhibit autophagy.