bluuebunny/crossref_metadata_2025 huggingface dataset:
Guided discovery learning to improving triangular understanding in blind student
Authors: Faulina Mayang , Andriyani Andriyani
Published: September 2020

Tujuan dari penelitian ini adalah untuk mengetahui pengaruh pembelajaran guided discovery dalam meningkatkan pemahaman siswa tunanetra. Penelitian ini merupakan penelitian eksperimental dengan desain Single Subject Research (SSR) A-B. Siswa yang digunakan sebagai subjek dalam penelitian ini adalah siswa kelas VII MTs Yaketunis Yogyakarta. Pengumpulan data melalui tes, observasi dan wawancara. Analisis data dilakukan berdasarkan hasil pada fase baseline maupun intervensi yang berada pada dua kondisi, yaitu dalam kondisi dan antar kondisi. Hal ini terlihat dari peningkatan hasil tes pemahaman siswa pada fase baseline dengan skor 43, 41 dan 50 menjadi 80, 83, 81, dan 90 pada fase intervensi.  Demikian halnya dengan hasil analisis dalam kondisi yang menunjukkan bahwa fase intervensi memiliki arah kecenderungan arah dan stabilitas yang signifikan lebih meningkat daripada fase baseline. Melalui observasi dan wawancara juga diketahui konsistensi jawaban yang menunjukkan pemahaman konsep sudut siswa sudah terkonstruksi. Dengan pembelajaran guided discovery, siswa tidak hanya sekedar menghafal konsep tapi lebih pada aktivitas belajar bermakna dengan  mengonstruksi dan memahami konsep secara mandiri, sehingga hasil belajarnya bertahan lama dalam memori siswa.
Informal and Private: Veto Threats Over the Freedom of Information Act
Authors: Baron Kevin
Published: September 2020

Building from Azari and Smith’s (2012) work on informal institutions, we understand the veto bargaining function as informal, operating within the formal rules and constraints of the legislative development process, as there are no formal rules to govern presidential bargaining with Congress. The president’s power to persuade becomes contextual and situational to the issue, individual, and moment in time. The Freedom of Information Act (FOIA) is employed as a case to examine a policy issue that presidents do not want, as it serves as a congressional check on executive power. Examining the development of FOIA, we can examine how and why presidents choose to employ a private bargaining strategy. Using the same policy issue across three administrations – Lyndon Johnson, Richard Nixon, and Gerald Ford – provides consistency in examining the political contexts on an issue each president wanted to avoid but was forced to engage with by Congress.
Learning Race, Gender, and Intersectionality through Integrative Political Science
Authors: Franco Josue
Published: September 2020

Gender, race, and intersectionality are increasingly relevant in our diversifying country. Political science courses centered on these concepts are emerging throughout the United States, but not yet ubiquitous. Integrative political science courses merge lectures, journal articles analysis teams, public policy project teams, and simulations in a single course to facilitate a multi-faceted learning experience with students and between students. Utilizing a Technology-Enabled Active Learning classroom, approximately 90 students enrolled in a race and gender course organize into journal article analysis, public policy project, and simulation teams. How do students benefit from the integration of science, practice, and simulation in learning about race, gender, and intersectionality?
Assessment of Men's Role on Mother Care when Pregnant, Birth and Breastfeeding
Authors: Awang Mariana Ngundju
Published: September 2020

Background: The maternal mortality rate (MMR) in East Sumba is one of the highest in the province of East Nusa Tenggara (NTT) for the past five years (2011-2015). Maternal mortality in East Sumba District is 76.7% occurred during childbirth and 23.3% during pregnancy. The Sumba tribe is based on patriaki culture which prioritizes men as the masters. Male participation is very small, but their control of women in deciding for women to use contraceptives or not very dominant. Methods: The type of research used was qualitative research by means of in-depth interviews and FGDs on 20 respondents. Results: Men were very instrumental in helping their wives from becoming pregnant, giving birth and breastfeeding according to cultural figures, customs, husbands and wives. Conclusion: The role of men when pregnant wives prepare themselves as prospective fathers by following the development of pregnancy and supporting the preparation of childbirth, when the wife gives birth to accompany the wife before and during childbirth by giving motivation to face the pain, struggle to give birth to the baby, and when breastfeeding wife Supports the success of breastfeeding, especially exclusive breastfeeding

Keywords: Male role, East Sumba culture, Traditional figure, Religious figure
Family Support and Quality of Life in Breast Cancer Patients
Authors: Noorhidayah Noorhidayah , Widiastuti Hesti Prawita , Kalsum Umi
Published: September 2020

Introduction: In these days, one of the terrifying cancers for women throughout the world is breast cancer. The treatment of cancer should be holistic. Patients need family support to create a good quality of life. The purpose of this study was to determine the relationship between family support and quality of life in breast cancer patients at the Chemotherapy Unit of Abdul Wahab Sjahranie Hospital Samarinda. Methods: Quantitative research with analytical study and cross-sectional design. Sampling was done with a total sample of 76 respondents. The instruments used in this research were family support standards and the Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) for quality of life. The data were analyzed using the Chi-Square test. Results: The p-value was 0.003, OR = 4.090, indicating that there was a relationship between family support and quality of life in breast cancer patients. Conclusion: There is a relationship between family support and quality of life in breast cancer patients. It is expected that the hospital can proceed in providing health education and motivation to breast cancer patients and their families related to the importance of family support for the quality of life of breast cancer patients.

Keywords: family support; breast cancer; quality of life
The Influence of Endorphine Massage on Anxiety in Mothers During Their 3rd Trimester Pregnancy
Authors: Sukesi Niken
Published: September 2020

The 3rd trimester of pregnancy is the time for one to prepare both physiologically and psychologically for baby birth and nursing. The pregnancy during this final trimester causes incovenience due to fetus and uterus enlargements. The pain during pregnancy and approaching the labor in pregnant mothers might increase their anxiety. One of attempts to reduce this anxiety resulting from pain in pregnant mothers employs nonpharmacologic method in the form of endorphin massage. This research was quasi experimental with one group pretest posttest design. It used analytical comparative research method since the researcher tried to study the existence of endorphin massage influence on anxiety in pregnant mothers. The results revealed that there was some mean differences before and after the therapy was given. The mean score before the therapy was given was 1.6 and after the therapy was given was 1.2. The difference between these two mean score was 0.4. From the analysis, it was found that the p-value was 0.037, meaning that there was a significant difference of anxiety level between before and after the provision of endorphin massage.

Keywords: endorphin; pregnancy; anxiety
Membrane Inlet Mass Spectrometry: A Powerful Tool for Algal Research
Authors: Burlacot Adrien , Burlacot François , Li-Beisson Yonghua , Peltier Gilles
Published: September 2020

Since the first great oxygenation event, photosynthetic microorganisms have continuously shaped the Earth’s atmosphere. Studying biological mechanisms involved in the interaction between microalgae and cyanobacteria with the Earth’s atmosphere requires the monitoring of gas exchange. Membrane inlet mass spectrometry (MIMS) has been developed in the early 1960s to study gas exchange mechanisms of photosynthetic cells. It has since played an important role in investigating various cellular processes that involve gaseous compounds (O2, CO2, NO, or H2) and in characterizing enzymatic activitiesin vitroorin vivo. With the development of affordable mass spectrometers, MIMS is gaining wide popularity and is now used by an increasing number of laboratories. However, it still requires an important theory and practical considerations to be used. Here, we provide a practical guide describing the current technical basis of a MIMS setup and the general principles of data processing. We further review how MIMS can be used to study various aspects of algal research and discuss how MIMS will be useful in addressing future scientific challenges.
Evaluación de los Estilos de Vida y Valores de los Turistas que visitan la Amazonía Ecuatoriana
Authors: Manosalvas Vaca Luis Oswaldo , Manosalvas Vaca Carlos Aníbal , Gamboa Rios María Germania , Solís Morejón Viviana Catalina
Published: September 2020

La investigación analiza los valores y estilos de vida de los turistas que visitan la Amazonía ecuatoriana, y para este caso específico se evaluó una muestra de turistas que visitaron la ciudad de Puyo, provincia de Pastaza, con respecto a los diferentes  atractivos turísticos, lugares de alojamiento y restauración, la evaluación se desarrolló mediante la aplicación de instrumentos de medición basado en el método LATIR de estilos de vida propuesto por el investigador Rolando Arellano y el método VALS II (values and life styles). La metodología fue con un enfoque cuantitativo, descriptivo y transversal mediante la aplicación de encuestas válidas y confiables usadas en varias investigaciones en otros contextos y regiones, con ello, se pudo establecer el perfil de los clientes para cada uno de los segmentos identificados, los resultados indicaron que el estilo de vida del turista que visita la región corresponde a Progresistas, Modernas y Sofisticados, con respecto a los valores, la dimensión que predomina es el turista entusiasta, las otras dimensiones arrojaron valores poco favorables y desfavorables,  lo cual permite plantear estrategias para mejorar el turismo en la región.
Gestión Municipal, midiendo la Incidencia del Presupuesto Participativo y el Desempeño Laboral en ella; caso: Municipio de La Molina, 2020
Authors: Silva Siu Daniel Ricardo , Guerrero Bejarano Maria Auxiliadora , Córdova García Ulises
Published: September 2020

El principal objetivo de este trabajo fue encontrar si el desempeño de los trabajadores y la forma de manejar el presupuesto afecta los resultados obtenidos por la administración municipal, utilizando como el caso de estudio a la Municipalidad de La Molina, en Lima Perú, estudio cuantitativo, se encuestó a trabajadores de la municipalidad en mención, cien en total, utilizando tres encuentas previamente validadas por expertos, todas las herramientas poseen cuestionarios con escalas de likert se midió la confibilidad con Alpha de Crombach. Se demostró que en este caso el presupuesto participativo y el desempeño laboral tienen incidencia en la gestión del municipio de La Molina.
Exploring the Genetic Background of the Differences in Nest-Building Behavior in European Rabbit
Authors: Benedek Ildikó , Altbӓcker Vilmos , Zsolnai Attila , Molnár Tamás
Published: September 2020

Once a day, nursing and absentee mothering make the wild rabbit (Oryctolagus cuniculus) an ideal model animal for measuring differences in maternal behavior. Behavioral events and their hormonal regulation leading to parturition are well documented; however, the genetic background behind individual differences in this complex process is unknown. Decreased progesterone hormone level and the reduction of progesterone receptor activity are crucial to initiating the collection of nest material. The progesterone receptor gene is a likely candidate affecting nest-building behavior. In addition to several known point mutations in the progesterone receptor gene of the European wild rabbit, we have found a new mutation in the promoter region of the gene at 2682 T > C. Although this new single nucleotide polymorphism (SNP) was not involved in the formation of the nest-building behavior, an SNP (2464G > A) already described in the promoter region showed an association with individual differences in the initiation of hay carrying. The distribution of this SNP delivered an opposite result compared to domestic rabbits. Genotype (GG) with high uterine capacity was most frequent; the hereditary value of the trait was h2 = 0.10. Thus, progesterone receptor gene polymorphism may manifest in individual differences affecting breeding success in this species.
Effects of Rumen-Protected Choline on Growth Performance, Carcass Characteristics and Blood Lipid Metabolites of Feedlot Lambs
Authors: Kawas Jorge R. , Garcia-Mazcorro Jose F. , Fimbres-Durazo Hector , Ortega-Cerrilla Maria E.
Published: September 2020

Choline is an essential nutrient for animals, but dietary choline is degraded in the rumen, and thus, should be offered as rumen-protected choline (RPC) in ruminants. In this article, we investigate the effect of RPC supplementation in feedlot lambs. Forty intact male Saint Croix lambs (average: 20.3 kg, 3–4 months of age) on a high grain-low roughage base feed were randomly assigned to four treatments (0, 0.1, 0.2, and 0.3% RPC on dry-matter basis; n = 10 per group). RPC was offered for 90 days after 15 days of adaptation. RPC supplementation was not associated with significant differences in dry matter intake, weight gain, gain:feed ratio, carcass weights, and the dressing percentages. There was a linear decrease in height to the shoulder (p = 0.013) and longissimus muscle area (p = 0.051) with higher RPC levels, and a higher backfat thickness and yield grade with 0.3% RPC compared to 0.1% RPC (p < 0.05). Blood triglycerides concentrations were higher in control (0% RPC) compared to 0.3% RPC (p = 0.008). The lack of significant effects on growth performance and the results on backfat thickness and yield grade, may indicate undesirable effects associated with RPC supplementation. More research is needed to establish the needs and specific quantities of RPC supplementation in feedlot lambs.
Numerical Simulation Analysis of the Impact of Urbanization on an Extreme Precipitation Event over Beijing–Tianjin–Hebei, China
Authors: Zhang Jing , Zhou Yu-shu , Shen Xin-yong
Published: September 2020

In this study, an extreme rainstorm that occurred in the Beijing–Tianjin–Hebei (BTH) region in China on 19–20 July 2016 is simulated and analyzed using the Weather Research and Forecasting model, coupled with a multilayer urban canopy scheme, to reveal the impact of urbanization on the extreme precipitation process in the region. The results show that the urban heat island effect (that is, surface warming and an increased near-ground sensible heat flux, which leads to increased vertical motion and atmospheric instability layer strengthening) plays a dominant role in the urban modification of rainfall during the early stages of urbanization, resulting in an increase of 6–10 mm in average hourly precipitation in urban and downwind areas. With the further development of urbanization in the BTH region, particularly in the big cities of Beijing and Tianjin, the large-scale expansion of the urban surface reduces the surface moisture, the evaporation of surface water from the ground, and the height of the atmospheric boundary layer, leading to an urban dry island effect brought about by the lack of near-surface water vapor, which inhibits an increase in precipitation. The positive effect of the urban heat island on precipitation was offset by the urban dry island effect, so the increase in precipitation in the urban areas was not obvious, but an increased range of 8–10 mm was noted. The existence of large cities changes the position of the strong upward movement of air, and convective upward movement is more likely to occur between the suburbs. With the further expansion of the underlying surface of the adjacent cities of Beijing and Tianjin, the upward movement between the two cities coincides, leading to an obvious increase in precipitation between the two cities.
mTOR-Dependent Role of Sestrin2 in Regulating Tumor Progression of Human Endometrial Cancer
Authors: Shin Jiha , Bae Jeongyun , Park Sumi , Kang Hyun-Goo , Shin Seong Min , Won Gunho , Kim Jong-Seok , Cho Ssang-Goo , Choi Youngsok , Oh Sang-Muk , Shin Jongdae , Kim Jeong Sig , Park Hwan-Woo
Published: September 2020

Oncogenic activation of the mammalian target of rapamycin complex 1 (mTORC1) leads to endometrial cancer cell growth and proliferation. Sestrin2 (SESN2), a highly conserved stress-inducible protein, is involved in homeostatic regulation via inhibition of reactive oxygen species (ROS) and mTORC1. However, the role of SESN2 in human endometrial cancer remains to be investigated. Here, we investigated expression, clinical significance, and underlying mechanisms of SESN2 in endometrial cancer. SESN2 was upregulated more in endometrial cancer tissues than in normal endometrial tissues. Furthermore, upregulation of SESN2 statistically correlated with shorter overall survival and disease-free survival in patients with endometrial cancer. SESN2 expression strongly correlated with mTORC1 activity, suggesting its impact on prognosis in endometrial cancer. Additionally, knockdown of SESN2 promoted cell proliferation, migration, and ROS production in endometrial cancer cell lines HEC-1A and Ishikawa. Treatment of these cells with mTOR inhibitors reversed endometrial cancer cell proliferation, migration, and epithelial–mesenchymal transition (EMT) marker expression. Moreover, in a xenograft nude mice model, endometrial cancer growth increased by SESN2 knockdown. Thus, our study provides evidence for the prognostic significance of SESN2, and a relationship between SESN2, the mTORC1 pathway, and endometrial cancer growth, suggesting SESN2 as a potential therapeutic target in endometrial cancer.
Monitoring DNA Damage and Repair in Peripheral Blood Mononuclear Cells of Lung Cancer Radiotherapy Patients
Authors: Lobachevsky Pavel N. , Bucknell Nicholas W. , Mason Joel , Russo Diane , Yin Xiaoyu , Selbie Lisa , Ball David L. , Kron Tomas , Hofman Michael , Siva Shankar , Martin Olga A.
Published: September 2020

Thoracic radiotherapy (RT) is required for the curative management of inoperable lung cancer, however, treatment delivery is limited by normal tissue toxicity. Prior studies suggest that using radiation-induced DNA damage response (DDR) in peripheral blood mononuclear cells (PBMC) has potential to predict RT-associated toxicities. We collected PBMC from 38 patients enrolled on a prospective clinical trial who received definitive fractionated RT for non-small cell lung cancer. DDR was measured by automated counting of nuclear γ-H2AX foci in immunofluorescence images. Analysis of samples collected before, during and after RT demonstrated the induction of DNA damage in PBMC collected shortly after RT commenced, however, this damage repaired later. Radiation dose to the tumour and lung contributed to the in vivo induction of γ-H2AX foci. Aliquots of PBMC collected before treatment were also irradiated ex vivo, and γ-H2AX kinetics were analyzed. A trend for increasing of fraction of irreparable DNA damage in patients with higher toxicity grades was revealed. Slow DNA repair in three patients was associated with a combined dysphagia/cough toxicity and was confirmed by elevated in vivo RT-generated irreparable DNA damage. These results warrant inclusion of an assessment of DDR in PBMC in a panel of predictive biomarkers that would identify patients at a higher risk of toxicity.
Inflammasome Sensor NLRP1 Confers Acquired Drug Resistance to Temozolomide in Human Melanoma
Authors: Zhai Zili , Samson Jenny Mae , Yamauchi Takeshi , Vaddi Prasanna K. , Matsumoto Yuko , Dinarello Charles A. , Ravindran Menon Dinoop , Fujita Mayumi
Published: September 2020

Cancer cells gain drug resistance through a complex mechanism, in which nuclear factor-κB (NF-κB) and interleukin-1β (IL-1β) are critical contributors. Because NACHT, LRR and PYD domains-containing protein (NLRP) inflammasomes mediate IL-1β maturation and NF-κB activation, we investigated the role of inflammasome sensor NLRP1 in acquired drug resistance to temozolomide (TMZ) in melanoma. The sensitivity of melanoma cells to TMZ was negatively correlated with the expression levels of O6-methylguanine-DNA methyltransferase (MGMT), the enzyme to repair TMZ-induced DNA lesions. When MGMT-low human melanoma cells (1205Lu and HS294T) were treated with TMZ for over two months, MGMT was upregulated, and cells became resistant. However, the resistance mechanism was independent of MGMT, and the cells that acquired TMZ resistance showed increased NLRP1 expression, NLRP inflammasome activation, IL-1β secretion, and NF-κB activity, which contributed to the acquired resistance to TMZ. Finally, blocking IL-1 receptor (IL-1R) signaling with IL-1R antagonist decreased TMZ-resistant 1205Lu tumor growth in vivo. Although inflammation has been associated with drug resistance in various cancers, our paper is the first to demonstrate the involvement of NLRP in the development of acquired drug resistance. Because drug-tolerant cancer cells become cross-tolerant to other classes of cancer drugs, NLRP1 might be a suitable therapeutic target in drug-resistant melanoma, as well as in other cancers.
Alkali-Activated Binders Based on Tungsten Mining Waste and Electric-Arc-Furnace Slag: Compressive Strength and Microstructure Properties
Authors: Sedira Naim , Castro-Gomes João
Published: September 2020

The valorization and reusing of mining waste has been widely studied in recent years. Research has demonstrated that there is great potential for reusing mining waste for construction applications. This work experimentally investigated the strength development, pore structure, and microstructure of a binary alkali-activated binder. This is based on tungsten mining waste mud (TMWM) and electric-arc-furnace slag (EAF-Slag) using different proportions of TMWM (10, 20, 30, 40, and 50 vt.%). The precursors were activated using sodium silicate (Na2SiO3) and potassium hydroxide (KOH 8M) as alkaline activator solution with solid:liquid weight ratio = 3. Pastes were used to assess the compressive strength of the blended binder and their microstructure. The reaction products were characterized by X-ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS), and Fourier transform infra-red (FT-IR) spectroscopy, while the porosity and the pores size properties were examined by mercury intrusion porosimetry (MIP). The results show that the partial replacement of TMWM with EAF-Slag exhibited better mechanical properties than the 100TM-AAB. A maximum strength value of 20.1 MPa was obtained in the binary-AAB sample prepared with 50 vt.% TMWM and EAF-Slag. The pastes that contained a higher dosage of EAF-Slag became more compact with lower porosity and finer pore-size distribution. In addition, the results obtained by SEM-EDS confirmed the formation of different types of reaction products in the 100TM-AAB, 100FS-AAB, and the binary-AABs mixtures such as N-A-S-H, C-A-S-H and (N, C)-A-S-H gels frameworks in the system as the major elements detected are Si, Al, Ca, and Na.
Benchmarking Wind Farm Projects by Means of Series Two-Stage DEA
Authors: Tsolas Ioannis E.
Published: September 2020

This paper presents a data envelopment analysis (DEA) approach to benchmark a group of wind farm (WF) projects in Greece by employing a series two-stage structure. In the first stage, the investment performance of projects is evaluated using contract data and site wind conditions, though in the second stage the WF operational efficiency is evaluated using data on production inputs and output. Inefficiency occurs in both the construction and operating stages, but the construction process appears to be more inefficient relative to the operating phase. Moreover, WF size is related to operating efficiency and sensitivity analysis results identify wind speed and WF installation capacity as the factors that affect the investment performance and operational efficiency, respectively. The proposed approach is an addition to the existing literature and it can be used by managers and facility operators.
Assessment of Rusty Blackbird Habitat Occupancy in the Long Range Mountains of Newfoundland, Canada Using Forest Inventory Data
Authors: Manson Kathleen K. E. , McDermott Jenna P. B. , Powell Luke L. , Whitaker Darroch M. , Warkentin Ian G.
Published: September 2020

Rusty blackbirds (Euphagus carolinus), once common across their boreal breeding distribution, have undergone steep, range-wide population declines. Newfoundland is home to what has been described as one of just two known subspecies (E. c. nigrans) and hosts some of the highest known densities of the species across its extensive breeding range. To contribute to a growing body of literature examining rusty blackbird breeding ecology, we studied habitat occupancy in Western Newfoundland. We conducted 1960 point counts across a systematic survey grid during the 2016 and 2017 breeding seasons, and modeled blackbird occupancy using forest resource inventory data. We also assessed the relationship between the presence of introduced red squirrels (Tamiasciurus hudsonicus), an avian nest predator, and blackbird occupancy. We evaluated 31 a priori models of blackbird probability of occurrence. Consistent with existing literature, the best predictors of blackbird occupancy were lakes and ponds, streams, rivers, and bogs. Red squirrels did not appear to have a strong influence on blackbird habitat occupancy. We are among the first to model rusty blackbird habitat occupancy using remotely-sensed landcover data; given the widespread availability of forest resource inventory data, this approach may be useful in conservation efforts for this and other rare but widespread boreal species. Given that Newfoundland may be a geographic stronghold for rusty blackbirds, future research should focus on this distinct population.
Using Matrix-Product States for Open Quantum Many-Body Systems: Efficient Algorithms for Markovian and Non-Markovian Time-Evolution
Authors: Finsterhölzl Regina , Katzer Manuel , Knorr Andreas , Carmele Alexander
Published: September 2020

This paper presents an efficient algorithm for the time evolution of open quantum many-body systems using matrix-product states (MPS) proposing a convenient structure of the MPS-architecture, which exploits the initial state of system and reservoir. By doing so, numerically expensive re-ordering protocols are circumvented. It is applicable to systems with a Markovian type of interaction, where only the present state of the reservoir needs to be taken into account. Its adaption to a non-Markovian type of interaction between the many-body system and the reservoir is demonstrated, where the information backflow from the reservoir needs to be included in the computation. Also, the derivation of the basis in the quantum stochastic Schrödinger picture is shown. As a paradigmatic model, the Heisenberg spin chain with nearest-neighbor interaction is used. It is demonstrated that the algorithm allows for the access of large systems sizes. As an example for a non-Markovian type of interaction, the generation of highly unusual steady states in the many-body system with coherent feedback control is demonstrated for a chain length of N=30.
Antifragility Predicts the Robustness and Evolvability of Biological Networks through Multi-Class Classification with a Convolutional Neural Network
Authors: Kim Hyobin , Muñoz Stalin , Osuna Pamela , Gershenson Carlos
Published: September 2020

Robustness and evolvability are essential properties to the evolution of biological networks. To determine if a biological network is robust and/or evolvable, it is required to compare its functions before and after mutations. However, this sometimes takes a high computational cost as the network size grows. Here, we develop a predictive method to estimate the robustness and evolvability of biological networks without an explicit comparison of functions. We measure antifragility in Boolean network models of biological systems and use this as the predictor. Antifragility occurs when a system benefits from external perturbations. By means of the differences of antifragility between the original and mutated biological networks, we train a convolutional neural network (CNN) and test it to classify the properties of robustness and evolvability. We found that our CNN model successfully classified the properties. Thus, we conclude that our antifragility measure can be used as a predictor of the robustness and evolvability of biological networks.
Intermittency and Critical Scaling in Annular Couette Flow
Authors: Takeda Kazuki , Duguet Yohann , Tsukahara Takahiro
Published: September 2020

The onset of turbulence in subcritical shear flows is one of the most puzzling manifestations of critical phenomena in fluid dynamics. The present study focuses on the Couette flow inside an infinitely long annular geometry where the inner rod moves with constant velocity and entrains fluid, by means of direct numerical simulation. Although for a radius ratio close to unity the system is similar to plane Couette flow, a qualitatively novel regime is identified for small radius ratio, featuring no oblique bands. An analysis of finite-size effects is carried out based on an artificial increase of the perimeter. Statistics of the turbulent fraction and of the laminar gap distributions are shown both with and without such confinement effects. For the wider domains, they display a cross-over from exponential to algebraic scaling. The data suggest that the onset of the original regime is consistent with the dynamics of one-dimensional directed percolation at onset, yet with additional frustration due to azimuthal confinement effects.
Hybrid Harmony Search–Artificial Intelligence Models in Credit Scoring
Authors: Goh Rui Ying , Lee Lai Soon , Seow Hsin-Vonn , Gopal Kathiresan
Published: September 2020

Credit scoring is an important tool used by financial institutions to correctly identify defaulters and non-defaulters. Support Vector Machines (SVM) and Random Forest (RF) are the Artificial Intelligence techniques that have been attracting interest due to their flexibility to account for various data patterns. Both are black-box models which are sensitive to hyperparameter settings. Feature selection can be performed on SVM to enable explanation with the reduced features, whereas feature importance computed by RF can be used for model explanation. The benefits of accuracy and interpretation allow for significant improvement in the area of credit risk and credit scoring. This paper proposes the use of Harmony Search (HS), to form a hybrid HS-SVM to perform feature selection and hyperparameter tuning simultaneously, and a hybrid HS-RF to tune the hyperparameters. A Modified HS (MHS) is also proposed with the main objective to achieve comparable results as the standard HS with a shorter computational time. MHS consists of four main modifications in the standard HS: (i) Elitism selection during memory consideration instead of random selection, (ii) dynamic exploration and exploitation operators in place of the original static operators, (iii) a self-adjusted bandwidth operator, and (iv) inclusion of additional termination criteria to reach faster convergence. Along with parallel computing, MHS effectively reduces the computational time of the proposed hybrid models. The proposed hybrid models are compared with standard statistical models across three different datasets commonly used in credit scoring studies. The computational results show that MHS-RF is most robust in terms of model performance, model explainability and computational time.
Studies on Dynamic Properties of Ultracapacitors Using Infinite r–C Chain Equivalent Circuit and Reverse Fourier Transform
Authors: Rajput Shailendra , Kuperman Alon , Yahalom Asher , Averbukh Moshe
Published: September 2020

The specific power storage capabilities of double-layer ultracapacitors are receiving significant attention from engineers and scientific researchers. Nevertheless, their dynamic behavior should be studied to improve the performance and for efficient applications in electrical devices. This article presents an infinite resistor–capacitor (r–C) chain-based mathematical model for the analysis of double layer ultracapacitors. The internal resistance and capacitance were measured for repetitive charging and discharging cycles. The magnitudes of internal resistance and capacitance showed approximately ±10% changes for charge-discharge processes. Electrochemical impedance spectroscopy investigations revealed that the impedance of a double-layer ultracapacitor does not change significantly in the temperature range of (−30 °C to +30 °C) and voltage range of (0.3376–2.736 V). The analysis of impedance data using the proposed mathematical model showed good agreement between the experimental and theoretical data. The dynamic behavior of the ultracapacitor was successfully represented by utilizing the proposed infinite r–C chains equivalent circuit, and the reverse Fourier transform analysis. The r–C electrical equivalent circuit was also analyzed using the PSIM simulation software to study the dynamic behavior of ultracapacitor parameters. The simulation study yields an excellent agreement between the experimental and calculated voltage characteristics for repetitive charging-discharging processes.
Multi Usage Applications of Li-Ion Battery Storage in a Large Photovoltaic Plant: A Practical Experience
Authors: Wenge Christoph , Pietracho Robert , Balischewski Stephan , Arendarski Bartlomiej , Lombardi Pio , Komarnicki Przemyslaw , Kasprzyk Leszek
Published: September 2020

The number of large energy storage units installed in the power system has increased over the last few years. This fact remains closely linked to the increase in the share of renewable energy in electricity generation. This is necessary to maintain the stability of the grid, which is becoming increasingly difficult to maintain due to the growing number of renewable energy sources (RES). Energy production from these sources is difficult to estimate, and possible unplanned shortages and surpluses in production are the cause of voltage and frequency fluctuations, which is an undesirable state. Consequently, the use of energy storage not only contributes to the regulation of grid operation but can also, under appropriate conditions, constitute an additional load if too much energy is generated by RES, or the source when the generation from RES is insufficient. The main contributions of this paper are as follows: A presentation of practical results achieved by implementing two optimal control strategies for a 1 MW (0.5 MWh) battery energy storage (BES) cooperating with a large 144 MW photovoltaic farm. In the first case, the BES was used to generate curtailment at photovoltaic farm to avoid power grid overload. The second case focuses on maximizing profits from selling the energy produced in periods when the unit price for energy was the highest according to energy market forecasts. In both cases, the storage was used simultaneously to cover the producer’s own demand, which eliminated the costs associated with the purchase of energy from the operator, especially during the night supply. A technical and economic evaluation was prepared for both cases, considering the real profits from the investment. The potential of using the BES to increase the functionality of photovoltaic energy sources was determined and discussed in the paper.
Gas-Wetting Alteration by Fluorochemicals and Its Application for Enhancing Gas Recovery in Gas-Condensate Reservoirs: A Review
Authors: Jin Jiafeng , Sun Jinsheng , Rong Kesheng , Lv Kaihe , Nguyen Tuan A. H. , Wang Ren , Huang Xianbin , Bai Yingrui , Liu Jingping , Wang Jintang
Published: September 2020

Gas-wetting alteration is a versatile and effective approach for alleviating liquid-blockage that occurs when the wellbore pressure of a gas-condensate reservoir drops below the dew point. Fluorochemicals are of growing interest in gas-wetting alteration because of their high density of fluorine groups and thermal stability, which can change the reservoir wettability into more favorable conditions for liquids. This review aims to integrate the overlapping research between the current knowledge in organic chemistry and enhanced oil and gas recovery. The difference between wettability alteration and gas-wetting alteration is illustrated, and the methods used to evaluate gas-wetting are summarized. Recent advances in the applications of fluorochemicals for gas-wetting alteration are highlighted. The mechanisms of self-assembling adsorption layers formed by fluorochemicals with different surface morphologies are also reviewed. The factors that affect the gas-wetting performance of fluorochemicals are summarized. Meanwhile, the impacts of gas-wetting alteration on the migration of fluids in the pore throat are elaborated. Furthermore, the Wenzel and Cassie-Baxter theories are often used to describe the wettability model, but they are limited in reflecting the wetting regime of the gas-wetting surface; therefore, a wettability model for gas-wetting is discussed. Considering the promising prospects of gas-wetting alteration, this study is expected to provide insights into the relevance of gas-wetting, surface morphology and fluorochemicals, further exploring the mechanism of flow efficiency improvement of fluids in unconventional oil and gas reservoirs.
Frequency Analysis of Solar PV Power to Enable Optimal Building Load Control
Authors: Olama Mohammed , Dong Jin , Sharma Isha , Xue Yaosuo , Kuruganti Teja
Published: September 2020

In this paper, we present a flexibility estimation mechanism for buildings’ thermostatically controlled loads (TCLs) to enable the distribution level consumption of the majority of solar photovoltaic (PV) generation by local building TCLs. The local consumption of PV generation provides several advantages to the grid operation as well as the consumers, such as reducing the stress on the distribution network, minimizing voltage fluctuations and two-way power flows in the distribution network, and reducing the required battery storage capacity for PV integration. This would result in increasing the solar PV generation penetration levels. The aims of this study are twofold. First, spectral (frequency) analyses of solar PV power generation together with the power consumption of multiple building TCLs (such as heating, ventilation, and air conditioning (HVAC) systems, water heaters, and refrigerators) are performed. These analyses define the bandwidth over which these TCLs can operate and also describe the PV generation frequency bandwidth. Such spectral analyses, in frequency domain, can help identify the flexible components of PV generation that can be consumed by the various TCLs through optimal building load utilization. Second, a quadratic optimization problem based on model predictive control is formulated to allow consuming most of the low and medium frequency content of the PV power locally by building TCLs, while maintaining occupants’ comfort and TCLs’ physical constraints. The solution to the proposed optimization problem is achieved using optimal control strategies. Numerical results show that most of the low and medium frequency content of the PV generation can be consumed locally by building TCLs. The remaining high-frequency content of the PV generation can then be stored/offset using energy storage systems.
Modelling of Distributed Resource Aggregation for the Provision of Ancillary Services
Authors: Lesniak Adam , Chudy Dawid , Dzikowski Rafal
Published: September 2020

Nowadays, ancillary services (ASs) are usually provided by large power generating units located in transmission networks, while smaller assets connected to distribution systems remain passive. It is expected that active distribution systems will start to play an important role due to numerous issues related to power system operation caused mainly by developing renewable generation and restrictions imposed on conventional power generating units by climate policies. The future development of the power system management will also lead to the establishment of new market agents such as distributed resource aggregators (DRAs). The article presents the concept of the DRA as part of an active distribution system enabling small resources to participate in wholesale markets, provide ASs and indicates the functions of the DRA coordinator in the modern power system. The proposed method of the DRA structure modelling with the use of the mixed-integer linear programming (MILP) is aimed at evaluating the optimal operation pattern of participating resources, the desired shape of the load profile at the point of common coupling (PCC) and the AS provision. The performed simulations of the DRA’s operation show that various types of aggregated resources located in distribution networks are able to provide different services effectively to support the power system in terms of load–generation balancing and allow for further development of renewables.
Operating and Investment Models for Energy Storage Systems
Authors: Miletić Marija , Pandžić Hrvoje , Yang Dechang
Published: September 2020

In the context of climate changes and the rapid growth of energy consumption, intermittent renewable energy sources (RES) are being predominantly installed in power systems. It has been largely elucidated that challenges that RES present to the system can be mitigated with energy storage systems (ESS). However, besides providing flexibility to intermittent RES, ESS have other sources of revenue, such as price arbitrage in the markets, balancing services, and reducing the cost of electricity procurement to end consumers. In order to operate the ESS in the most profitable way, it is often necessary to make optimal siting and sizing decisions, and to determine optimal ways for the ESS to participate in a variety of energy and ancillary service markets. As a result, many publications on ESS models with various goals and operating environments are available. This paper aims at presenting the results of these papers in a structured way. A standard ESS model is first outlined, and that is followed by a literature review on operational and investment ESS models at the transmission and distribution levels. Both the price taking and price making models are elaborated on and presented in detail. Based on the examined body of work, the paper is concluded with recommendations for future research paths in the analysis of ESS.
Elastic and Frictional Properties of Fault Zones in Reservoir-Scale Hydro-Mechanical Models—A Sensitivity Study
Authors: Treffeisen Torben , Henk Andreas
Published: September 2020

The proper representation of faults in coupled hydro-mechanical reservoir models is challenged, among others, by the difference between the small-scale heterogeneity of fault zones observed in nature and the large size of the calculation cells in numerical simulations. In the present study we use a generic finite element (FE) model with a volumetric fault zone description to examine what effect the corresponding upscaled material parameters have on pore pressures, stresses, and deformation within and surrounding the fault zone. Such a sensitivity study is important as the usually poor data base regarding specific hydro-mechanical fault properties as well as the upscaling process introduces uncertainties, whose impact on the modelling results is otherwise difficult to assess. Altogether, 87 scenarios with different elastic and plastic parameter combinations were studied. Numerical modelling results indicate that Young’s modulus and cohesion assigned to the fault zone have the strongest influence on the stress and strain perturbations, both in absolute numbers as well as regarding the spatial extent. Angle of internal friction has only a minor and Poisson’s ratio of the fault zone a negligible impact. Finally, some general recommendations concerning the choice of mechanical fault zone properties for reservoir-scale hydro-mechanical models are given.
Parameters Identification of Equivalent Model of Permanent Magnet Synchronous Generator (PMSG) Wind Farm Based on Analysis of Trajectory Sensitivity
Authors: Zhang Jian , Cui Mingjian , He Yigang
Published: September 2020

As wind farms have great influences on power system stability, it is essential to develop an adaptive as well as robust equivalent model of it. In this paper, a detailed equivalent model of PMSG wind farm and initialization method is developed. The trajectory sensitivity of parameters is analyzed. Then, the key parameters are estimated using improved Genetic Learning Particle Swarm Optimization (GLPSO) hybrid algorithm with phasor measurement unit (PMU). The description and generalization capability, stability for parameter identification of the equivalent model under wake effects, and when some wind turbines are off-line or wind speed is unknown after an event are analyzed. The maximum differences between the values of estimated parameters and their real ones are less than 10% for the proportional magnification constant of DC voltage controller Kp2 and grid side current controller Kp3. The convergence rate and global optimization performance of the improved GLPSO hybrid algorithm is 0.5 times higher than the classical particle swarm optimization algorithm (PSO) and genetic algorithm (GA).
On the Participation of Power-To-Heat Assets in Frequency Regulation Markets—A Danish Case Study
Authors: Iov Florin , Khatibi Mahmood , Bendtsen Jan Dimon
Published: September 2020

Due to the new green energy policies, district heating companies are being increasingly encouraged to exploit power-to-heat assets, e.g., heat pumps and electric boilers, in their distribution networks besides the traditional central combined heat and power units. The increased utilization of these assets will generate a more complex interaction between power distribution grids and district heating networks including markets for provision of ancillary services. Enabling the participation of power-to-heat units in the ancillary service markets, e.g., frequency reserves, may increase the revenue streams for assets’ owners. However, some technical challenges must first be addressed, including optimization of portfolios of assets that accounts for ancillary service markets, new coordination and operational schemes for portfolio of assets, increase data exchange and interactions with transmission system operators, and new local control schemes for units. This paper proposes a systematic model based design approach for assessment of provision of frequency regulation by power-to-heat assets using the smart grid architecture model. The proposed approach is demonstrated in a Real-Time Control Hardware-in-the-Loop laboratory environment.