How to improve open rotor aerodynamics at cruise and take-off

AbstractA key challenge in open rotor design is getting the optimum aerodynamics at both the cruise and take-off conditions. This is particularly difficult because the operation and the requirements of an open rotor are very different at cruise compared to takeoff. This paper uses CFD results to explore the impact of various design changes on the cruise and take-off flow-fields. The paper then considers how a given open rotor design is best operated at take-off to minimise noise whilst maintaining high thrust. The main findings are that various design modifications can be applied to control the flow features that lead to lost efficiency at cruise and increased noise emission at take-off. A breakdown of the lost power terms from CFD solutions demonstrates how developments in open rotor design have led to reduced aerodynamic losses. At take-off, the operating point of the open rotor should be set such that the non-dimensional lift is as high as possible, without causing significant flow separation. This can be achieved through suitable amounts of re-pitch and speed up applied to a design. Comparisons with fully three-dimensional CFD show that the amount of re-pitch required can be determined using simplified methods such as two-dimensional CFD and a Blade Element Method.This is the accepted manuscript. The final published version is available at http://aerosociety.com/News/Publications/Aero-Journal/Online/2522/How-to-improve-open-rotor-aerodynamics-at-cruise-and-takeoff

Assessing the Potential to Detect Oil Spills In and Under Snow Using Airborne Ground-Penetrating Radar

With recent increased interest in oil and gas exploration and development in the Arctic comes increased potential for an accidental hydrocarbon release into the cryosphere, including within and at the base of snow. There is a critical need to develop effective and reliable methods for detecting such spills. Numerical modeling shows that ground-penetrating radar (GPR) is sensitive to the presence of oil in the snow pack over a broad range of snow densities and oil types. Oil spills from the surface drain through the snow by the mechanisms of unsaturated flow and form geometrically complex distributions that are controlled by snow stratigraphy. These complex distributions generate an irregular pattern of radar reflections that can be differentiated from natural snow stratigraphy, but in many cases, interpretation will not be straightforward. Oil located at the base of the snow tends to reduce the impedance contrast with the underlying ice or soil substrate resulting in anomalously low-amplitude radar reflections. Results of a controlled field experiment using a helicopter- borne, 1000-MHz GPR system showed that a 2-cm-thick oil film trapped between snow and sea ice was detected based on a 51% decrease in reflection strength. This is the first reported test of GPR for the problem of oil detection in and under snow. Results indicate that GPR has the potential to become a robust tool that can substantially improve oil spill characterization and remediation

PERTUNJUKAN KESENIAN TERBANG DI KECAMATAN CIATER KABUPATEN SUBANG DAN BENTUK PELESTARIANNYA SEBAGAI BAHAN AJAR PELATIHAN EKSTRAKURIKULER DI SMA

Logita Embang. 2105 “Pertunjukan Kesenian Terbang dan Bentuk Pelestariannya Sebagai Bahan Ajar Pelatihan Ekstrakurikuler Di SMA” Sekolah Pasca Sarjana UPI. Latar belakang: keberadaan pertunjukan kesenian terbang asli yang hampir tidak diminati oleh generasi muda yang beranggapan merupakan kesenian yang bertradisi lama. Masalah penelitian: Bagaimana bentuk pertunjukan kesenian terbang? Bagaimana struktur teks yang terkandung dalam lagu-lagu? Bagaimana ko-teks dan konteks dan fungsi pada pertunjukan kesenian terbang? Bagaimana bentuk pelestarian di SMA? Tujuan dari penelitian: mendeskripsikan pertunjukan kesenian terbang, menyajikan ancangan buku panduan pelatihan ekstrakurikuler di SMA. Teori yang digunakan: teori kebudayaan, tradisi lisan, bentuk dan struktur teks, kajian semantik, bunyi dan teori isi tradisi lisan. Penelitian ini menggunakan metode deskriptif kualitatif. Teknik pengumpulan data: teknik observasi partisipatif, wawancara, dan dokumentasi. Instrumen penelitian: peneliti sendiri dan dibantu dengan pedoman wawancara, observasi, catatan lapangan, tape recorder, dan kamera. Sumber datanya: pertunjukan kesenian terbang, teks lagu-lagu dan konteks. Analisis data dan pembahasan mengenai pertunjukan kesenian terbang, bentuk, analisis struktur semantik dan formula bunyi, ko-teks dan konteks dari lagu-lagu pertunjukan kesenian terbang, Teks lagu-lagu dalam pertunjukan kesenian terbang memiliki struktur semantik yang beragam. Formula bunyinya berupa pengulangan bunyi kata, baik dalam baris, maupun antar baris dengan irama yang dinamis. Konteks dari pertunjukan kesenian terbang ini tidak terikat oleh ruang dan waktu, namun harus mempertimbangkan suasana. Fungsi dari pertunjukan kesenian terbang selain sebagai penghibur juga sebagai unsur pendidikan, pranata kehidupan sosial, fungsi keagamaan. Upaya pelestarian dari pertunjukan kesenian terbang, yaitu melalui pembuatan bahan ajar berupa ancangan buku panduan pelatihan kegiatan ekstrakurikuler di SMA.----------Logita Embang. 2015 “Arts Terbang Performance and Instructional Material As a preservation From Extracurricular Training in School”. Post Graduate of UPI. Background: Young generations are not interested in existence of the original art terbang performance, they thought that it is old tradition. The research problem: how is form of art terbang performance? How the structure of the text contained in the songs? How co-text and context of the function of to show art terbang? What are the forms of preservation in high school? The purpose of the research: to describe art terbang performance, presenting definition guidebook extracurricular training in high school. The used theory: the theory of culture, oral traditions, the shape and structure of the text, the study of semantics, the sound and content of the theory of oral tradition. This research used qualitative descriptive method. Data collection techniques: technique of participant observation, interviews, and documentation. Instrument of the research: the researchers themselves and assisted with interview, observation, field notes, tape recorder, and camera. Source of data: art terbang performance of songs and context. Data analysis and discussion of art terbang performance, to analyze the shape, structure, semantic, and sound formula, co-text and context of art performance songs terbang. Text songs of art terbang performance have a diverse semantic structure. Formula repetition of sound such as the sound of the word, both in rows with a dynamic rhythm. Context of art terbang performance is not bound by the cast and the time, but must consider the atmosphere. The function of the art terbang performance as an entertainer also other than as a component of education, social life institution, a religious function. Conservation effort of art terbang performance is through making material definition guide book training extracurricular in high school

Ferroelectric Transitions in SrxBa(1-x)Nb2O6 - Effect of Thermal History on the Functional Properties

Many functional materials used in todays electronic equipment have a high content lead. Due to the environmental challenges related to production and usage of such materials, extensive research has been preformed on lead-free alternatives. Strontium barium niobate (SBNX) is one of many material systems suitable for replacing the lead-based materials. Functional properties and crystal structure of SBN has in this study been investigated with respect to variations in thermal history. Samples of SBN30, SBN40 and SBN50 have been synthesized through the solid state route. Each composition has been heat treated for at least 12 hours at various temperatures, and subsequently characterized by powder X-ray diffraction (all compositions) and dielectric spectroscopy (only SBN40 and SBN50). The peak in dielectric permittivity is observed to shift towards lower temperatures for increased sintering temperature. For SBN40, the peak in dielectric permittivity shifted 100C due to an increase in sintering temperature from 1300C to 1400C. A transition from normal ferroelectric to relaxor behavior has been observed as a result of increasing sintering temperature. For samples sintered at 1350C and 1400C, increasing frequency caused both a dispersion of measured permittivities and a shift towards higher temperatures for the peak in dielectric permittivity. The crystal structure was also affected by the increasing sintering temperature. Both unit cell parameters show temperature dependent behavior, causing the unit cell volume to decrease as the sintering temperature increases

Comparison of predicted properties of Ekofisk oils based on Crude Assay data - Evaluation of the predicted behaviour of satellites relative to previous studies.

ConocoPhillips Skandinavia ASpublishedVersio

Hvordan opplever elever i ungdomsskoler måltidsituasjonen ved implementering av gratis, varm skolemat? – En kvalitativ studie

Bachelor i SamfunnsernæringBakgrunn: Barn og unge tilbringer mye tid på skolen. Skolen er en viktig arena for læring og sosialt samvær, og skolemåltidet kan fungere som et viktig samlingspunkt. I dag er det ingen norsk lov om skolemat, det er en uenighet om skolemat burde innføres i norske skoler, og hva som ville vært den beste modellen. Folkehelseinstituttet har i 2019/2020 gjennomført en pilotstudie på fem skoler for å prøve ut en modell for gratis skolemat med utgangspunkt i de fasilitetene skolene har i dag. Bacheloroppgavens hovedmål: Undersøke hvordan elever i ungdomsskoler opplevde måltidsituasjonen ved implementering av gratis og varm skolemat. Metode og utvalg: Oppgaven hadde et kvalitativt forskningsdesign og inkluderte fokusgruppeintervjuer fra fem skoler, der to var i Trøndelag, og de tre resterende i Oslo. Intervjuene ble gjennomført i etterkant av implementeringen. Til sammen deltok 31 ungdomsskoleelever. Analyseringen av datamaterialet ble inspirert av tematisk analyse. Resultater: Elevene var generelt positive til organiseringen av et gratis varmt skolemåltid og nevnte få utfordringer. De la vekt på at organiseringen la til rette for å i større grad være sosial under et felles måltid. Elevene så på skolematen som en sosial og hyggelig begivenhet, og under skolematen snakket elevene mer sammen, også på tvers av klasser. Videre var elevene positive til å spise sammen med lærerne og oppfattet de som mindre strenge enn før, og at de i større grad snakket sammen. Konklusjon: Funnene tyder på at implementeringen av gratis varm skolemat bidro til å styrke det sosiale miljøet rundt skolemåltidet

Masse og elite i den romerske republikk

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Hvordan fremstilles barns uttalelser i en rettsprosess? En tematisk analyse av hvordan barn høres i foreldretvistsaker som har gått til hovedforhandling

Denne kvalitative studien undersøker hvordan barn blir hørt i foreldretvistsaker som har gått til hovedforhandling. Målet med studien er å få et innblikk i hvordan barns uttalelser fremstilles i en rettslig høring og hvilke forståelsesrammer eller diskurser som preger denne fremstillingen i referatene fra høringen og i domsavsigelsen. Datamaterialet består av 6 referater fra barnehøringene og de tilhørende tingrettsdommer. Barna som ble hørt var i alderen 5-10 år. Referatene ble analysert ved hjelp av tematisk analyse, og materialet er sortert i fire kategorier: Rammene for høring av barn og barnets rettigheter, beskrivelser av barnets relasjoner, fremstillingen av barnets troverdighet og forholdet mellom barnets uttalelser og dommers bestemmelse av bo og samvær. Analysen viste at referatene unnlot å nevne om barnet var blitt informert om sine rettigheter og hvilke konsekvenser uttalelsen deres kan få. Konfliktnivået mellom foreldrene og hvordan dette berører barnet, er ikke tematisert. Videre blir barna framstilt som troverdige under visse forutsetninger. I tillegg er referatenes form og innhold, og relasjonen mellom referat og dom, vurdert opp mot en rettighetsdiskurs. Både tilretteleggingen for barnehøringen og framstilling av barna, bygger opp under denne diskursen, der det forutsettes et syn på barn som kompetent til å uttale seg om viktige spørsmål i dets liv (uttrykt i diskursen «Det kompetente barnet»). Samtidig viser studien også at barns sårbarhet blir tatt hensyn til i en høringskontekst (uttrykt i diskursen «Det sårbare barnet»). Dommene vektlegger barnets uttalelser avhengig av alder og modenhet, men samtidig er disse uttalelsene en av flere faktorer som er avgjørende for beslutningen om bo- og samværsordning. Et særlig funn var at referatene i all hovedsak fremstiller det som uproblematisk for barn å uttale seg om bo- og samværsordning. Funnene drøftes opp mot relevant teori.The aim of this study is to explore how children are heard in a court process in Norwegian custody cases. This qualitative study uses a thematic analytic approach in order to reveal the prevalent discourses regarding our view on children and see how these discourses influence and shape the settings of the court. The documents analyzed are the written reports from the interviews from the hearing of the children. The children, 6 in total, were aged between 5 and 10. Thematic analysis identified four different categories or groups in the material; (1) The circumstances for the hearing of the child or how the interviews were performed (2) How the children's familiar relationship or framework were described, (3) How the children's trustworthiness are described, and at last (4) The relationship between how the children have expressed themselves and the final rulings made by the court. The material used in this qualitative study is limited and the conclusions should be handled with care. However, a main finding from the thematic analysis is that information obtained from a child is generally evaluated as trustworthy, especially when obtained in an interview by a qualified person talking to the child alone. The child is considered as competent, trustworthy and should be heard in the court process. However, the circumstances for the interview, age and maturity and conflict level surrounding the child are also important for how the court evaluate the trustworthiness of the child. The child is identified as the vulnerable part in the conflict. Finally, the findings are discussed with regard to the discourses that the study argues is a part of our society, i.e. “The competent child” and “The vulnerable child” and relevant theory