Separable shape tensors for aerodynamic design

Grey Zachary J,Doronina Olga A,Glaws Andrew 한국CDE학회 2023 Journal of computational design and engineering Vol.10 No.1

Airfoil shape design is a classical problem in engineering and manufacturing. In this work, we combine principled physics-based considerations for the shape design problem with modern computational techniques using a data-driven approach. Modern and traditional analyses of two-dimensional (2D) and three-dimensional (3D) aerodynamic shapes reveal a flow-based sensitivity to specific deformations that can be represented generally by affine transformations (rotation, scaling, shearing, and translation). We present a novel representation of shapes that decouples affine-style deformations over a submanifold and a product submanifold principally of the Grassmannian. As an analytic generative model, the separable representation, informed by a database of physically relevant airfoils, offers: (i) a rich set of novel 2D airfoil deformations not previously captured in the data, (ii) an improved low-dimensional parameter domain for inferential statistics informing design/manufacturing, and (iii) consistent 3D blade representation and perturbation over a sequence of nominal 2D shapes.

종교적 체험 간증으로서 이사야 6장 읽기

재클린그레이 ( Jacqueline Grey ) 한세대학교 영산신학연구소 2020 영산신학저널 Vol.0 No.53

오순절주의는 하나님에 대해 아는 것만 아니라 하나님을 경험하는 것도 강조한다. 본고는 이사야 6장에 나오는 거룩한 하나님에 대한 이사야의 체험과 그것의 윤리적함축성을 연구한다. 본고는 먼저 현상학의 광범위한 문헌에 비추어 종교적 체험을 정의하는 것으로 시작할 것이다. 그 다음에는 이사야 6장에 나오는 선지자의 간증을 내러티브 분석을 통해 읽을 것이다. 이사야의 종교적 체험의 초점인 하나님의 거룩하심은 그를 깊게 사로잡았고, 이에 하나님의 거룩한 특성이 이사야 선지자가 언약백성들의 행위를 측정하는 결정적인 기준이 되었다. 이사야에게 있어 하나님의 거룩하심은 하나님의 백성을 위한 윤리적 함축성을 갖고 있다. 이 점은 선지자가 하나님의 환상을 보고 그 자신을 부정한 입술을 가진 사람들과 동일시하는 반응(사 6:5)에반영되었고, 연이어 나오는 냉소적인 공동체를 향한 메시지(사 6:9-13)에도 반영되었다. 이사야의 윤리적 메시지는 타인들을 향한 관심으로서 수행된 imitatio Dei(하나님닮아가기)의 하나다. 이는 도덕적 가치를 함양하는 데 있어 하나님과의 만남이 중요함을 강조한다. 끝으로, 본고는 거룩한 하나님과의 만남에서 흘러나온 오순절 공동체를 향한 윤리적 메시지에 어떤 함의들이 있는지 살펴볼 것이다. Pentecostalism emphasizes not only knowing about God but also experiencing God. This paper explores Isaiah’s experience of the holy God in Isaiah 6 and its ethical implications. The paper begins by defining religious experience in light of the broader literature of phenomenology. It then reads the testimony of the prophet in Isaiah 6 in light of narrative analysis. The holiness of God, the focus of Isaiah’s religious experience, so preoccupies the prophet that this characteristic of God becomes a crucial standard by which he measures the actions of the covenant people. For Isaiah, the holiness of God has ethical implications for the people of God. This is reflected in both his response to the vision of God whereby he identifies with the people of unclean lips (Is 6:5) and his subsequent message to the cynical community (Is 6:9-13). The ethical message of Isaiah is one of imitatio Dei, outworked as concern for others. This emphasizes the importance of an encounter with God for the development of moral values. Finally, the implications for the Pentecostal community of an ethical message that flows from an encounter with the holy God will be explored.

Release of K from Silicate Rock Powders

Clare Mccann,Safiya Mohammed,Neil Grey,Kirsten Brandt,Adrian Oila,Maggie White,Ian Singleton,David Manning 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Design of electrode materials for Li rechargeable batteries by integrating ab initio calculations with experiments

강기석,Gerbrand Ceder,Ying Shirley Meng,Clare P. Grey,Julien Breger 한국고분자학회 2008 한국고분자학회 학술대회 연구논문 초록집 Vol.33 No.1

Role of Amine-Cavity Interactions in Determining the Structure and Mechanical Properties of the Ferroelectric Hybrid Perovskite [NH₃NH₂]Zn(HCOO)₃

Kieslich, Gregor,Forse, Alexander C.,Sun, Shijing,Butler, Keith T.,Kumagai, Shohei,Wu, Yue,Warren, Mark R.,Walsh, Aron,Grey, Clare P.,Cheetham, Anthony K. American Chemical Society 2016 Chemistry of materials Vol.28 No.1

<P>Dense formate frameworks with a perovsldte-like architecture exhibit multiferroic behavior and tunable mechanical properties. In such materials, interactions between the protonated amine and the metal formate cavity have a large impact on the mechanical properties. We use complementary single-crystal X-ray diffraction and H-1 solid state nuclear magnetic resonance spectroscopy to investigate amine cavity interactions in [NH3NH2]Zn(HCOO)(3). The results suggest that these interactions can be described as salt bridges similar to those in proteins and artificially synthesized helical polymers, where ionic interactions and hydrogen bonds are present at the same time. Nanoindentation and high-pressure single-crystal X-ray diffraction were used to study the mechanical properties of [NH3NH2]Zn(HCOO)(3), yielding elastic moduli of E-001 = 26.5 GPa and E-110 = 24.6 GPa and a bulk modulus of K = 19 GPa. The mechanical properties suggest that, despite the relatively low packing density of [NH3NH2]Zn(HCOO)(3), the amine cavity interactions strengthen the framework significantly in comparison with related materials.</P>

Antimicrobial Effects of Virgin Coconut Oil and Its Medium-Chain Fatty Acids on Clostridium difficile

Michael Shilling,Laurie Matt,Evelyn Rubin,Mark Paul Visitacion,Nairmeen A. Haller,Scott F. Grey,Christopher J. Woolverton 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.12

Clostridium difficile is the leading cause of hospital-acquired antibiotic-associated diarrhea worldwide; in addition, the proliferation of antibiotic-resistant C. difficile is becoming a significant problem. Virgin coconut oil (VCO) has been shown previously to have the antimicrobial activity. This study evaluates the lipid components of VCO for the control of C. difficile. VCO and its most active individual fatty acids were tested to evaluate their antimicrobial effect on C. difficile in vitro. The data indicate that exposure to lauric acid (C12) was the most inhibitory to growth (P < .001), as determined by a reduction in colony-forming units per milliliter. Capric acid (C10) and caprylic acid (C8) were inhibitory to growth, but to a lesser degree. VCO did not inhibit the growth of C. difficile; however, growth was inhibited when bacterial cells were exposed to 0.15–1.2% lipolyzed coconut oil. Transmission electron microscopy (TEM) showed the disruption of both the cell membrane and the cytoplasm of cells exposed to 2 mg/mL of lauric acid. Changes in bacterial cell membrane integrity were additionally confirmed for VCO and select fatty acids using Live/Dead staining. This study demonstrates the growth inhibition of C. difficile mediated by medium-chain fatty acids derived from VCO.

Multiple Redox Modes in the Reversible Lithiation of High-Capacity, Peierls-Distorted Vanadium Sulfide

Britto, Sylvia,Leskes, Michal,Hua, Xiao,Hé,bert, Claire-Alice,Shin, Hyeon Suk,Clarke, Simon,Borkiewicz, Olaf,Chapman, Karena W.,Seshadri, Ram,Cho, Jaephil,Grey, Clare P. American Chemical Society 2015 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.137 No.26

<P>Vanadium sulfide VS<SUB>4</SUB> in the patronite mineral structure is a linear chain compound comprising vanadium atoms coordinated by disulfide anions [S<SUB>2</SUB>]<SUP>2–</SUP>. <SUP>51</SUP>V NMR shows that the material, despite having V formally in the d<SUP>1</SUP> configuration, is diamagnetic, suggesting potential dimerization through metal–metal bonding associated with a Peierls distortion of the linear chains. This is supported by density functional calculations, and is also consistent with the observed alternation in V–V distances of 2.8 and 3.2 Å along the chains. Partial lithiation results in reduction of the disulfide ions to sulfide S<SUP>2–</SUP>, via an internal redox process whereby an electron from V<SUP>4+</SUP> is transferred to [S<SUB>2</SUB>]<SUP>2–</SUP> resulting in oxidation of V<SUP>4+</SUP> to V<SUP>5+</SUP> and reduction of the [S<SUB>2</SUB>]<SUP>2–</SUP> to S<SUP>2–</SUP> to form Li<SUB>3</SUB>VS<SUB>4</SUB> containing tetrahedral [VS<SUB>4</SUB>]<SUP>3–</SUP> anions. On further lithiation this is followed by reduction of the V<SUP>5+</SUP> in Li<SUB>3</SUB>VS<SUB>4</SUB> to form Li<SUB>3+x</SUB>VS<SUB>4</SUB> (<I>x</I> = 0.5–1), a mixed valent V<SUP>4+</SUP>/V<SUP>5+</SUP> compound. Eventually reduction to Li<SUB>2</SUB>S plus elemental V occurs. Despite the complex redox processes involving both the cation and the anion occurring in this material, the system is found to be partially reversible between 0 and 3 V. The unusual redox processes in this system are elucidated using a suite of short-range characterization tools including <SUP>51</SUP>V nuclear magnetic resonance spectroscopy (NMR), S K-edge X-ray absorption near edge spectroscopy (XANES), and pair distribution function (PDF) analysis of X-ray data.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2015/jacsat.2015.137.issue-26/jacs.5b03395/production/images/medium/ja-2015-03395v_0013.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja5b03395'>ACS Electronic Supporting Info</A></P>

Structural complexity of layered-spinel composite electrodes for Li-ion batteries

Cabana, Jordi,Johnson, Christopher S.,Yang, Xiao-Qing,Chung, Kyung-Yoon,Yoon, Won-Sub,Kang, Sun-Ho,Thackeray, Michael M.,Grey, Clare P. Cambridge University Press (Materials Research Soc 2010 Journal of materials research Vol.25 No.8

<P>The complexity of layered-spinel <I>y</I>Li2MnO3·(1 - <I>y</I>)Li1+<I>x</I>Mn2-<I>x</I>O4 (Li:Mn = 1.2:1; 0 ≤ <I>x</I> ≤ 0.33; <I>y</I> ≥ 0.45) composites synthesized at different temperatures has been investigated by a combination of x-ray diffraction (XRD), x-ray absorption spectroscopy (XAS), and nuclear magnetic resonance (NMR). While the layered component does not change substantially between samples, an evolution of the spinel component from a high to a low lithium excess phase has been traced with temperature by comparing with data for pure Li1+<I>x</I>Mn2-<I>x</I>O4. The changes that occur to the structure of the spinel component and to the average oxidation state of the manganese ions within the composite structure as lithium is electrochemically removed in a battery have been monitored using these techniques, in some cases in situ. Our <SUP>6</SUP>Li NMR results constitute the first direct observation of lithium removal from Li2MnO3 and the formation of LiMnO2 upon lithium reinsertion.</P>