Microgrid Optimal Scheduling

This paper presents the optimal scheduling of renewable resources using interior point optimization for grid-connected and islanded microgrids (MG) that operate with no energy storage systems. The German Jordanian University (GJU) microgrid system is used for illustration. We present analyses for islanded and grid-connected MG with no storage. The results show a feasible islanded MG with a substantial operational cost reduction. We obtain an average of $1 k daily cost savings when operating an islanded compared to a grid-connected MG with capped grid energy prices. This cost saving is 10 times higher when considering varying grid energy prices during the day. Although the PV power is intermittent during the day, the MG continues to operate with a voltage variation that does not 10%. The results imply that MGs of GJU similar topology can optimally and safely operate with no energy storage requirements but considerable renewable generation capacity.

Smart Python Agents for Microgrids

Microgrids are revolutionary power systems that interconnect a mix of renewable power generation, load, storage systems, and inverters in a small-scale grid network. Operating microgrids while maintaining a consistent grid voltage and frequency during the islanding and disruption of renewables has been a challenging research problem. In this paper, a preliminary microgrid agent implementation is presented using SPADE (Smart Python Agent Development Environment) as a powerful development framework that has been used extensively in many application domains. Agents autonomously managed and operated microgrid individual components. A multiagent microgrid system was modeled to seamlessly operate and optimize energy balance by coordinating the actions of agents. Agents were built to forecast energy demand and solar power and coordinate to balance generation with load while maintaining optimal power flow and adequate network voltage and frequency.

内蒙古草原中东部现代表土植硅体组合与植被关系

对内蒙古中东部 14个典型植被表土样品进行植硅体分析 ,同时将其结果作对应分析。结果表明 :圆型和齿型在表土组合中占优势。圆型具有超代表性且在针茅草原和羊草草原表土组合中含量超过 5 0 %。针茅哑铃型和脊哑铃型在克氏针茅草原以及退化草原表土组合中含量偏高 ,可指示干的草原生境以及草原退化。蒿属块型表现为低代表性 ,即便是在冷蒿灌丛表土中 ,蒿属块型含量也较低。沙地云杉林和榆树灌丛生境特殊 ,它们的表土植硅体组合特征明显 ,前者以光滑块型、粗糙块型、规则多边型以及十字型等为主 ,后者以多铃型、三铃型、哑铃型以及简单哑铃型为特征。高山草甸和山杨林表土与研究区其它植被表土的相似性低。另外 ,研究区全新世古土壤剖面样品与表土样品的对应分析表明内蒙古中东部表土植硅体分析为恢复研究区全新世草原植被演化提供了参照物。

内蒙古典型草原禾本科植硅体形态

运用地层中植硅体组合解释过去草原植被及气候变化的关键之一 ,是要了解研究区现代植硅体形态及表土植硅体组合与现代植被的关系。文中研究内蒙古典型草原禾本科植物根、茎、叶、芒以及种子等不同部位的植硅体 ,对其中的 1 2种主要禾本科植物叶表皮短细胞硅酸体进行分类及统计。研究表明 :内蒙古典型草原禾本科叶表皮短细胞硅酸体可分为 8种特殊形态类型。C3 植物早熟禾亚科的叶表皮短细胞硅酸体形态多样。几乎所有早熟禾亚科都能产生圆型硅酸体 ,以贝加尔针茅 (85 .5 % )、大针茅 (89.7% )、克氏针茅 (90 % )以及芨芨草 (96 .6 % )中的圆型硅酸体含量最丰富。针茅哑铃型主要见于针茅植物叶表皮短细胞中 ,克氏针茅的针茅哑铃型含量相对较高。羊草中未见针茅哑铃型硅酸体。草、披缄草叶表皮短细胞硅酸体以齿型为主 ,分别含 87.3%和 5 7.2 % ,齿型在硬质早熟禾中也占一定比例。沙生冰草中的脊圆型占优势 ,含 74 .4 %。C3 植物早熟禾亚科的叶表皮短细胞产生的截锥型硅酸体含量较少。C4植物虎尾草亚科中的糙隐子草叶表皮短细胞硅酸体以黍哑铃型、简单哑铃型、鞍型为主 ;黍亚科狗尾草则以黍哑铃型占优势 (82 .9% )。

关节炎健康效用值映射法转换的研究进展

目的系统梳理关节炎健康效用值映射函数式,以期为国内关节炎健康效用值领域的发展研究提供可供借鉴的科学参考。方法以2007~2019年为检索年限,收集国内外关于关节炎相关疾病量表和健康效用值映射法转化的研究文献,汇总并整理。结果国外映射法研究较为成熟,国内尚处于起步阶段。关节炎映射法研究多为叙述性文献,实证类文献较少,研究对象覆盖深度缺乏全面性。结论加大样本量提升预测精确度;增加构建的映射模型种类,增强预测可信度;拓宽研究领域,增加疾病研究种类。

On the gating of mechanosensitive channels by fluid shear stress

Mechanosensation is an important process in biological fluid-structure interaction. To understand the biophysics underlying mechanosensation, it is essential to quantify the correlation between membrane deformation, membrane tension, external fluid shear stress, and conformation of mechanosensitive (MS) channels. Smoothed dissipative particle dynamics (SDPD) simulations of vesicle/cell in three types of flow configurations are conducted to calculate the tension in lipid membrane due to fluid shear stress from the surrounding viscous flow. In combination with a simple continuum model for an MS channel, SDPD simulation results suggest that shearing adhered vesicles/cells is more effective to induce membrane tension sufficient to stretch MS channels open than a free shear flow or a constrictive channel flow. In addition, we incorporate the bilayer-cytoskeletal interaction in a two-component model to probe the effects of a cytoskeletal network on the gating of MS channels.

酝酿中的美国专利法改革

目前,美国国会正面对一项新的专利法改革提案.2005年6月8日,众议院共和党籍议员拉马尔-史密斯(Lamar Smith)代表众议院的"知识产权分委员会"提出了对现行专利法的一揽子改革动议,统称"2005年专利改革法案"(The Patent Reform Act of 2005).这一美国立法的最新动态,值得关注.在分析这一改革提案前,有必要对美国专利制度的情况作一简要回顾.

Cultural Literacy and World Literature： A Case Study

How much more can be gained from a piece of World Literature when the reader is semiotically literate in the culture that produced the work？ What are the implications of introducing the element of cultural literacy into the teaching of world literature, and how might culturally contextualizing the narrative enhance the reading experience for those who may not be familiar with the national culture that produced the work？ This paper examines these questions using as a case study The Tale of Genji （n.d.）, a novel from llth century Japan and ＂La Troisi6me Jeunesse de Madame Prune＂ （1905）, a French text set in Japan at the turn of the 20th century. Using examples taken from each writer＇s text, the author will show how a knowledge of both the target culture and the time period in which the work was produced can serve as a critical tool for analyzing the text; the former text shall be used to argue for an integration of a cultural anthropology element into the teaching of world literature, while the latter example shall be used to argue for the importance of contextualizing a text within its historical creation period. In concluding, the author shall examine the ways in which including an element of cultural literacy can lead to a truly interdisciplinary, trans-national, and trans-linguistic understanding of a particular literary text.

AI-infused Semantic Model to Enrich and Expand Programming Question Generation

Creating practice questions for programming learning is not easy.It requires the instructor to diligently organize heterogeneous learning resources,that is,conceptual programming concepts and procedural programming rules.Today’s programming question generation(PQG)is still largely relying on the demanding creation task performed by the instructors without advanced technological support.In this work,we propose a semantic PQG model that aims to help the instructor generate new programming questions and expand the assessment items.The PQG model is designed to transform conceptual and procedural programming knowledge from textbooks into a semantic network by the Local Knowledge Graph(LKG)and Abstract Syntax Tree(AST).For any given question,the model queries the established network to find related code examples and generates a set of questions by the associated LKG/AST semantic structures.We conduct analysis to compare instructor-made questions from 9 undergraduate introductory programming courses and textbook questions.The results show that the instructormade questions had much simpler complexity than the textbook ones.The disparity of topic distribution intrigued us to further research the breadth and depth of question quality and also to investigate the complexity of the questions in relation to the student performances.Finally,we report a user study results on the proposed Artificial Intelligent-infused semantic PQG model in examining the machine-generated questions’quality.

Advances in homology directed genetic engineering of human pluripotent and adult stem cells

The ability to introduce precise genomic modifications in human cells has profound implications for both basic and applied research in stem cells, ranging from identification of genes regulating stem cell self-renewal and multilineage differentiation to therapeutic gene correction and creation of in vitro models of human diseases. However, the overall efficiency of this process is challenged by several factors including inefficient gene delivery into stem cells and low rates of homology directed site-specific targeting. Recent studies report the development of novel techniques to improve gene targeting efficiencies in human stem cells; these methods include molecular engineering of viral vectors to efficiently deliver episomal genetic sequences that can participate in homology directed targeting, as well as the design of synthetic proteins that can introduce double-stranded breaks in DNA to initiate such recombination events. This review focuses on the potential of these new technologies to precisely alter the human stem cell genome and also highlights the possibilities offered by the combination of these complementary strategies.

Real-Time Operation of Microgrids

Microgrid (MG) systems effectively integrate a generation mix of solar, wind, and other renewable energy resources. The intermittent nature of renewable resources and the unpredictable weather conditions contribute largely to the unreliability of microgrid real-time operation. This paper investigates the behavior of microgrid for different intermittent scenarios of photovoltaic generation in real-time. Reactive power coordination control and load shedding mechanisms are used for reliable operation and are implemented using OPAL-RT simulator integrated with Matlab. In an islanded MG, load shedding can be an effective mechanism to maintain generation-load balance. The microgrid of the German Jordanian University (GJU) is used for illustration. The results show that reactive power coordination control not only stabilizes the MG operation in real-time but also reduces power losses on transmission lines. The results also show that the power losses at some substations are reduced by a range of 6% - 9.8%.

Numerical and Experimental Evaluation of New Coldform Inverted “U” Section in Single or Multiple FamilyDwellings’ Flooring Systems

This article will introduce a new version of the metal deck for building residential flooring with a newly designed cold form U section. This flooring will allow residential structures to be built more quickly while also reducing the necessary thickness of the floor. The level of strength and deflection of this floor will be determined via analysis of a floor bed comprised of cold-formed inverted U sections (IUS) covered by sheathing that is subjected to different loading scenarios. The necessary computational quantities associated with the experiment have been compared to established laboratory values by performing all related and applicable tests. Then, these quantities are compared to different existing flooring techniques to determine the efficacy of this technique. The results show that this flooring technique can be effective and cost-efficient in residential applications.

Agents for Smart Power Grids

The future of electricity systems will compose of small-scale generation and distribution where end-users will be active participants with localized energy management systems that are able to interact on a free energy market. Software agents will most likely control power assets and interact together to decide the best and safest configuration of the power grid system. This paper presents a design of agents that can be deployed in real-time with capabilities that include optimization of resources, intensive computation, and appropriate decision-making. Jordan 51-bus system has been used for simulation with a total generation capacity of 4050 MW of which 230 MW represents renewable energy. The economic analyses demonstrated the use of smart grid technologies with 2016 generation—load profiles for nominal liquified gas (NLG) prices and ±20% sensitivity analysis. The results have shown variations in the range of 1% in the price of MWh with smart grid technologies. These variations are mainly driven by the fact that agents shift power generation to renewable power plants to produce maximum power at peak hours. As a result, there is a positive economic impact in both NLG ± 20% sensitivity analysis, due to the fact that agents coordinate to better displace expensive thermal generation with renewable generation. It is evident that renewable resources compensate for power at peak times and provide economic benefits and savings.

Regulation of D-galacturonate metabolism in <i>Caulobacter crescentus</i>by HumR, a LacI-family transcriptional repressor

The oligotrophic freshwater bacterium Caulobacter crescentus encodes a cluster of genes (CC_1487 to CC_1495) shown here to be necessary for metabolism of D-galacturonate, the primary constituent of pectin, a major plant polymer. Sequence analysis suggests that these genes encode a version of the bacterial hexuronate isomerase pathway. A conserved 14 bp sequence motif is associated with promoter regions of three operons within this cluster, and is conserved in homologous gene clusters in related alpha-Proteobacteria. Embedded in the hexuronate gene cluster is a gene (CC_1489) encoding a member of the LacI family of bacterial transcription factors. This gene product, designated here as HumR (hexuronate metabolism regulator), represses expression of the uxaA and uxaC operon promoters by binding to the conserved operator sequence. Repression is relieved in the presence of galacturonate or, to a lesser extent, by glucuronate. Other genes potentially involved in pectin degradation and hexuronate transport are also under the control of HumR. Adoption of a LacI-type repressor to control hexuronate metabolism parallels the regulation of xylose, glucose, and maltose utilization in C. crescentus, but is distinct from the use of GntR-type repressors to control pectin and hexuronate utilization in gamma-Proteobacteria such as Escherichia coli.

A Restricted, Adaptive Threshold Segmentation Approach for Processing High-Speed Image Sequences of the Glottis

In this paper, we propose a restricted, adaptive threshold approach for the segmentation of images of the glottis acquired from high speed video-endoscopy (HSV). The approach involves first, identifying a region of interest (ROI) that encloses the vocal-fold motion extent for each image frame as estimated by the different image sequences. This procedure is then followed by threshold segmentation restricted within the identified ROI for each image frame of the original image sequences, or referred to as sub-image sequences. The threshold value is adapted for each sub-image frame and determined by respective minimum gray-scale value that typically corresponds to a spatial location within the glottis. The proposed approach is practical and highly efficient for segmenting a vast amount of image frames since simple threshold method is adapted. Results obtained from the segmentation of representative clinical image sequences are presented to verify the proposed method.

Interoperable e-Infrastructure Services in Arabia

e-Infrastructures became critical platforms that integrate computational resources, facilities and repositories globally. The coordination and harmonization of advanced e-Infrastructure project developed with partners from Europe, Latin America, Arabia, Africa, China, and India contributed to developing interoperable platforms based on identity federation and science gateway technologies. This paper presents these technologies to support key services in the development of Arabia networking and services platform for research and education. The platform provides scientists, teachers, and students with seamless access to a variety of advanced resources, services, and applications available at regional e-Infrastructures in Europe and elsewhere. Users simply enter the credentials provided by their home institutions to get authenticated and do not need digital certificate-based mechanisms. Twenty applications from five scientific domains were deployed and integrated. Results showed that on average about 35,000 monthly jobs are running for a total of about 17,500 CPU wall-clock hours. Therefore, seamlessly integrated e-Infrastructures for regional e-Science activities are important resources that support scientists, students, and faculty with computational services and linkage to global research communities.

Multi-Agents for Microgrids

Microgrid systems are built to integrate a generation mix of solar and wind renewable energy resources that are generally intermittent in nature. This paper presents a novel decentralized multi-agent system to securely operate microgrids in real-time while maintaining generation, load balance. Agents provide a normal operation in a grid-connected mode and a contingency operation in an islanded mode for fault handling. Fault handling is especially critical in microgrid operation to simulate possible contingencies and microgrid outages in a real-world scenario. A robust agent design has been implemented using MATLAB-Simulink and Java Agent Development Framework technologies to simulate microgrids with load management and distributed generators control. The microgrid of the German Jordanian University has been used for simulation for Summer and Winter photovoltaic generation and load profiles. The results show agent capabilities to operate microgrid in real-time and its ability to coordinate and adjust generation and load. In a simulated fault incident, agents coordinate and adjust to a normal operation in 0.012 seconds, a negligible time for microgrid restoration. This clearly shows that the multi-agent system is a viable solution to operate MG in real-time.

青少年抑郁个体化识别与干预的三级框架

Depression in adolescents is a significant public health challenge with a high prevalence and negative outcomes.In the United States,the lifetime and 12-month prevalence rates of major depressive disorder(MDD)among 13-to 18-year-olds were 11.0%and 7.5%,respectively,prior to COVID-19.The COVID-19pandemic has further exacerbated the global trend of increasing rates of adolescent depression.

RECOMMENDED MESH ANCHORAGE DETAILS FOR STRAW BALE WALLS

Experimental studies on full-scale straw-bale walls have demonstrated the adequacy of straw-bale wall systems for resisting lateral loads from wind or seismic actions.Critical to the performance of the wall system is the anchorage of mesh reinforcement to the bottom plate and to the roof bearing assembly or top plate.Reported in this paper are the results of experiments examining mesh strength,anchorage strength,and failure mode for a variety of reinforcement meshes(steel,plastic,and hemp)and anchorage details.Because of the potential for new wood preservative pressure treatments to cause corrosion,stainless steel staples driven pneumatically into pressure-treated sill plates were tested in addition to electro-galvanized staples driven pneumatically into untreated sill plates and a heavier gauge staple driven manually into an untreated sill plate.Recommended anchorage details are identified,considering not only the test results but also the many other factors that must be considered in developing reliable,economical,and constructible details.

Cross-border issues and technology and management solutions during COVID-19

Critical cross-border issues have emerged during the COVID-19 pandemic,especially pertaining to security,supply chain,and education,which has led to several new challenges for management.The balance between potential risks and economic benefits has attracted the attention of both industry and academia.Hence,we invited three panelists to participate in the 2021 Association for Information Systems(AIS)Special Interest Group(SIG)on Information Systems in Asia Pacific(ISAP)workshop.The suggested solutions include the right Internet approach,multi-national cooperation to develop flexible global operations,and people’s education(especially refugees)to mitigate risks.These solutions encompass three levels,i.e.,technology,management,and society.