Relevant bibliographies by topics / LLT1

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Academic literature on the topic 'LLT1'

Author: Grafiati
Published: 4 June 2021
Last updated: 14 February 2022

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Journal articles on the topic "LLT1"

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Llibre, Alba, Lucy Garner, Amy Partridge, Gordon J. Freeman, Paul Klenerman, and Chris B. Willberg. "Expression of lectin-like transcript-1 in human tissues." F1000Research 5 (December 29, 2016): 2929. http://dx.doi.org/10.12688/f1000research.10009.1.

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Background: Receptor-ligand pairs of C-type lectin-like proteins have been shown to play an important role in cross talk between lymphocytes, as well as in immune responses within concrete tissues and structures, such as the skin or the germinal centres. The CD161-Lectin-like Transcript 1 (LLT1) pair has gained particular attention in recent years, yet a detailed analysis of LLT1 distribution in human tissue is lacking. One reason for this is the limited availability and poor characterisation of anti-LLT1 antibodies. Methods: We assessed the staining capabilities of a novel anti-LLT1 antibody clone (2H7), both by immunohistochemistry and flow cytometry, showing its efficiency at LLT1 recognition in both settings. We then analysed LLT1 expression in a wide variety of human tissues. Results: We found LLT1 expression in circulating B cells and monocytes, but not in lung and liver-resident macrophages. We found strikingly high LLT1 expression in immune-privileged sites, such as the brain, placenta and testes, and confirmed the ability of LLT1 to inhibit NK cell function. Conclusions: Overall, this study contributes to the development of efficient tools for the study of LLT1. Moreover, its expression in different healthy human tissues and, particularly, in immune-privileged sites, establishes LLT1 as a good candidate as a regulator of immune responses.
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Ghosh, Maloy, Kavitha Iyer Rodrigues, Sunit Maity, Sanghamitra Bhattacharjee, Yogendra Manjunath, Subhra Prakash Chakrabarty, Ashvini Kumar Dubey, Anurag Tiwari, Sathyabalan Murugesan, and Vivek Halan. "Novel monoclonal antibody therapeutics for metastatic castration resistant prostate cancer." Journal of Clinical Oncology 37, no. 15_suppl (May 20, 2019): e14222-e14222. http://dx.doi.org/10.1200/jco.2019.37.15_suppl.e14222.

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e14222 Background: Therapeutic potential of innate immunity comprising Natural killer cell based targets are beginning to unravel the complexity of immune responses. NK cells recognize and induce cytotoxicity of wide range of target cells, such as, tumor cells without prior antigen sensitization. In this study, we have studied Lectin-like transcript 1 (LLT1), a member of the C-type lectin super family, is expressed on target cells and various immune cells. LLT1 isoform 1, is known to interact with CD161, a critical receptor on NK cells. CD161 is expressed on most of human NK cells, NK-T cells, γδ T cells and so on. Tumors exploit the CD161- LLT1 interaction to evade host defense mechanism (“DO NOT KILL” signal); indicating LLT1 as an attractive immunotherapeutic strategy. Methods: Prostate cancer cell lines and other tumor cell lines were used to evaluate novel anti LLT1 antibodies for therapeutic potential - IFNγ production assays and tumor cell death assays were carried out. In vivo efficacy of these antibodies were established using PC3 xenograft in humanized mouse model (HuNOG-EXL). Results: Human androgen independent prostate cancer cell line, PC3 was studied for LLT1 expression and interactions with immune cells, to understand role of LLT1 in metastatic castration resistant prostate cancer (mCRPC). Overexpression of LLT1 on tumor cells was influenced by cytokines and various TLRs. Inhibition of CD161-LLT1 interaction with novel anti LLT1 antibodies leads to IFNγ production and consequent NK cell mediated cytotoxicity – hall mark of anti-tumor responses. Disruption of LLT1 - CD161 innate immunity axis with anti LLT1 antibody releases the break on NK cell cytotoxicity and hence, established a new therapeutic option. PC3 xenograft on HuNOG mouse revealed in vivo efficacy of LLT1 antibody. Significant tumor growth reduction was observed with specific anti LLT1 antibodies alone and in combination with check point antibodies. Thus, synergistic tumor growth reduction was established by combinatorial application of anti LLT1 antibody and PD1/PDL1 axis inhibitors. Conclusions: PC3 xenograft study and other results point to therapeutic opportunities in metastatic castration resistant prostate cancer, a disease condition which needs improved patient outcomes. The ligation of CD161/LLT1 will serve as a new immuno-oncology pair regulating innate and adaptive immune responses; novel human antibodies against LLT1 described here will bring therapeutic benefit to patients in need.
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Sanchez-Canteli, Mario, Francisco Hermida-Prado, Christian Sordo-Bahamonde, Irene Montoro-Jiménez, Esperanza Pozo-Agundo, Eva Allonca, Aitana Vallina-Álvarez, et al. "Lectin-Like Transcript 1 (LLT1) Checkpoint: A Novel Independent Prognostic Factor in HPV-Negative Oropharyngeal Squamous Cell Carcinoma." Biomedicines 8, no. 12 (November 25, 2020): 535. http://dx.doi.org/10.3390/biomedicines8120535.

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Lectin-like transcript 1 (LLT1) expression by tumor cells contributes to immune evasion, thereby emerging as a natural killer (NK) cell-mediated immunotherapeutic target. This study is the first to investigate LLT1 expression (encoded by CLEC2D gene) in head and neck cancers to ascertain its impact on patient prognosis. LLT1 expression was analyzed by immunohistochemistry in a homogeneous cohort of human papillomavirus (HPV)-negative oropharyngeal squamous cell carcinomas (OPSCC), and correlated with clinical data. Results were further validated using transcriptomic data from the TCGA database. Tumoral LLT1 expression was detected in 190/221 (86%) OPSCC specimens, whereas normal pharyngeal epithelium was negative. Patients harboring LLT1-positive tumors showed significantly lower disease-specific (DSS) and overall survival (OS) (p = 0.049 and p = 0.036, respectively, log-rank test). High density of LLT1-positive tumor-infiltrating lymphocytes (TIL) was also frequently detected in 160 (73%) OPSCC samples, and significantly associated with better DSS and OS (p < 0.001 and p = 0.007, respectively). Multivariate Cox analysis further revealed that tumoral LLT1 expression and infiltration of LLT1-positive TIL were independent prognostic factors for DSS and OS. CLEC2D mRNA levels are also significantly increased in primary tumors compared to normal tissue. Strikingly, the prognostic impact of CLEC2D mRNA levels varied depending on HPV status in OPSCC, and among distinct cancer types. CLEC2D expression was significantly correlated with NK cell infiltration using the MCP-counter model. These findings uncover LLT1/CLEC2D as an independent prognostic factor in HPV-negative OPSCC, and a potential novel target for immunotherapy.
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Skálová, Tereza, Jan Bláha, Karl Harlos, Jarmila Dušková, Tomáš Koval', Jan Stránský, Jindřich Hašek, Ondřej Vaněk, and Jan Dohnálek. "Four crystal structures of human LLT1, a ligand of human NKR-P1, in varied glycosylation and oligomerization states." Acta Crystallographica Section D Biological Crystallography 71, no. 3 (February 26, 2015): 578–91. http://dx.doi.org/10.1107/s1399004714027928.

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Human LLT1 is a C-type lectin-like ligand of NKR-P1 (CD161, geneKLRB1), a C-type lectin-like receptor of natural killer cells. Using X-ray diffraction, the first experimental structures of human LLT1 were determined. Four structures of LLT1 under various conditions were determined: monomeric, dimeric deglycosylated after the firstN-acetylglucosamine unit in two forms and hexameric with homogeneous GlcNAc2Man5glycosylation. The dimeric form follows the classical dimerization mode of human CD69. The monomeric form keeps the same fold with the exception of the position of an outer part of the long loop region. The hexamer of glycosylated LLT1 consists of three classical dimers. The hexameric packing may indicate a possible mode of interaction of C-type lectin-like proteins in the glycosylated form.
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Buller, Casey W., Porunelloor A. Mathew, and Stephen O. Mathew. "Roles of NK Cell Receptors 2B4 (CD244), CS1 (CD319), and LLT1 (CLEC2D) in Cancer." Cancers 12, no. 7 (July 1, 2020): 1755. http://dx.doi.org/10.3390/cancers12071755.

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Natural killer (NK) cells play a pivotal role in the immune system, especially in the recognition and clearance of cancer cells and infected cells. Their effector function is controlled by a delicate balance between the activating and inhibitory signals. We have identified 2B4 (CD244, SLAMF4) and CS1 (CD319, SLAMF7) as NK cell receptors regulating NK cell cytotoxicity. Lectin-like transcript 1 (LLT1), a member of the C-type lectin-like domain family 2 (CLEC2D), induced IFN-γ production but did not directly regulate cytolytic activity. Interestingly, LLT1 expressed on other cells acts as a ligand for an NK cell inhibitory receptor NKRP1A (CD161) and inhibits NK cytolytic function. Extensive research has been done on novel therapies that target these receptors to increase the effector function of NK cells. The 2B4 receptor is involved in the rejection of melanoma cells in mice. Empliciti, an FDA-approved monoclonal antibody, explicitly targets the CS1 receptor and enhances the NK cell cytotoxicity against multiple myeloma cells. Our studies revealed that LLT1 is expressed on prostate cancer and triple-negative breast cancer cells and allows them to evade NK-cell-mediated killing. In this review, we describe NK cell receptors 2B4, CS1, and LLT1 and their potential in targeting cancer cells for NK-cell-mediated immunotherapy. New cancer immunotherapies like chimeric antigen receptor T (CAR-T) and NK (CAR-NK) cells are showing great promise in the treatment of cancer, and CAR cells specific to these receptors would be an attractive therapeutic option.
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Mathew, Stephen O., Pankaj Chaudhary, Sheila B. Powers, Jamboor K. Vishwanatha, and Porunelloor A. Mathew. "Overexpression of LLT1 (OCIL, CLEC2D) on prostate cancer cells inhibits NK cell-mediated killing through LLT1-NKRP1A (CD161) interaction." Oncotarget 7, no. 42 (September 8, 2016): 68650–61. http://dx.doi.org/10.18632/oncotarget.11896.

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Mahjoub, Nada, Sophie Dhorne-Pollet, Walter Fuchs, Marie-Laure Endale Ahanda, Elke Lange, Barbara Klupp, Anoop Arya, et al. "A 2.5-Kilobase Deletion Containing a Cluster of Nine MicroRNAs in the Latency-Associated-Transcript Locus of the Pseudorabies Virus Affects the Host Response of Porcine Trigeminal Ganglia during Established Latency." Journal of Virology 89, no. 1 (October 15, 2014): 428–42. http://dx.doi.org/10.1128/jvi.02181-14.

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ABSTRACTThe alphaherpesvirus pseudorabies virus (PrV) establishes latency primarily in neurons of trigeminal ganglia when only the transcription of the latency-associated transcript (LAT) locus is detected. Eleven microRNAs (miRNAs) cluster within the LAT, suggesting a role in establishment and/or maintenance of latency. We generated a mutant (M) PrV deleted of nine miRNA genes which displayed properties that were almost identical to those of the parental PrV wild type (WT) during propagationin vitro. Fifteen pigs were experimentally infected with either WT or M virus or were mock infected. Similar levels of virus excretion and host antibody response were observed in all infected animals. At 62 days postinfection, trigeminal ganglia were excised and profiled by deep sequencing and quantitative RT-PCR. Latency was established in all infected animals without evidence of viral reactivation, demonstrating that miRNAs are not essential for this process. Lower levels of the large latency transcript (LLT) were found in ganglia infected by M PrV than in those infected by WT PrV. All PrV miRNAs were expressed, with highest expression observed for prv-miR-LLT1, prv-miR-LLT2 (in WT ganglia), and prv-miR-LLT10 (in both WT and M ganglia). No evidence of differentially expressed porcine miRNAs was found. Fifty-four porcine genes were differentially expressed between WT, M, and control ganglia. Both viruses triggered a strong host immune response, but in M ganglia gene upregulation was prevalent. Pathway analyses indicated that several biofunctions, including those related to cell-mediated immune response and the migration of dendritic cells, were impaired in M ganglia. These findings are consistent with a function of the LAT locus in the modulation of host response for maintaining a latent state.IMPORTANCEThis study provides a thorough reference on the establishment of latency by PrV in its natural host, the pig. Our results corroborate the evidence obtained from the study of several LAT mutants of other alphaherpesviruses encoding miRNAs from their LAT regions. Neither PrV miRNA expression nor high LLT expression levels are essential to achieve latency in trigeminal ganglia. Once latency is established by PrV, the only remarkable differences are found in the pattern of host response. This indicates that, as in herpes simplex virus, LAT functions as an immune evasion locus.
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Kamishikiryo, Jun, Hideo Fukuhara, Yuki Okabe, Kimiko Kuroki, and Katsumi Maenaka. "Molecular Basis for LLT1 Protein Recognition by Human CD161 Protein (NKRP1A/KLRB1)." Journal of Biological Chemistry 286, no. 27 (May 13, 2011): 23823–30. http://dx.doi.org/10.1074/jbc.m110.214254.

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Human Th17 cells express high levels of CD161, a member of the killer cell lectin-like receptor (KLR) family (also referred to as NK receptor-P1A (NKRP1A) or KLRB1), as a representative marker. CD161 is also expressed on natural killer (NK) cells and NKT cells. Lectin-like transcript 1 (LLT1), another KLR family member, was recently identified as a ligand for CD161. This interaction may play pivotal roles in the immunomodulatory functions of Th17 cells as well as those of NK and NKT cells. However, the molecular basis for the interaction is poorly understood. Here we show that the extracellular domain of CD161 bound directly to LLT1 with a Kd of 48 μm and with the fast kinetics typical of cell-cell recognition receptors. Mutagenesis revealed that the similar membrane-distal β-sheet and loop regions of both CD161 and LLT1 were utilized for the binding, and notably, these regions correspond to the ligand-binding sites for major histocompatibility complex (MHC)-recognizing KLRs. Furthermore, we found a pair of detrimental mutations for both molecules that restored the binding. These results reveal a new template model for the recognition mode between the KLR family members and provide insights into the molecular mechanism underlying Th17/NK/NKT-mediated immune responses.
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Bialoszewska, Agata, and Jacek Malejczyk. "Biological and Clinical Significance of Human NKRP1A/LLT1 Receptor/Ligand Interactions." Critical Reviews in Immunology 38, no. 6 (2018): 479–89. http://dx.doi.org/10.1615/critrevimmunol.2019029559.

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Mathew, P. "The LLT1 receptor induces IFN-γ production by human natural killer cells." Molecular Immunology 40, no. 16 (March 2004): 1157–63. http://dx.doi.org/10.1016/j.molimm.2003.11.024.

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Dissertations / Theses on the topic "LLT1"

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Llibre, Alba. "Expression, regulation and function of lectin-like transcript 1 (LLT1)." Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:bc16a4f5-103b-4322-9647-eda802ed7157.

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Receptor-ligand pairs of C-type lectin-like proteins have been shown to orchestrate and modulate immune responses within particular immune cell subsets or in distinct body locations. The function of CD161 and Lectin-Like Transcript 1 (LLT1) has not been extensively studied, partially due to the lack of validated anti-LLT1 antibodies. Here, I characterised two novel anti-LLT1 monoclonal antibodies (2H7 and 7G7). Using them for flow cytometric and immunohistological staining, I characterised the expression of LLT1 in different healthy human tissues and found that LLT1 levels were particularly high in immune-privileged sites. Germinal centres (GC) are microanatomical structures that are critical for the development of high-affinity antibodies and B cell memory. They are organised into two zones, light and dark, with coordinated roles controlled by local signalling. LLT1 protein is known to be expressed on B cells, but its functional role in the GC reaction has not been explored. I found high expression of LLT1 on GC-associated B cells, early plasmablasts and GC- derived lymphomas. LLT1 expression was readily induced via BCR, CD40 and CpG stimulation on B cells. Ubiquitous expression of CD161 on Follicular Dendritic Cells (FDCs) was revealed, as well as on a subset of T follicular cells. Triggering of LLT1 supported B cell activation, CD83 upregulation and Chemokine (C-X-C Motif) Receptor 4 (CXCR4) downregulation, which is consistent with a role in drivingtransition from a dark to a light zone phenotype. Overall, these data suggest that LLT1-CD161 interactions play a novel and important role in B cell maturation within the GC in humans. A deep understanding of the GC reaction and the process of B cell selection could provide invaluable knowledge into effective vaccine design, generation of auto-antibodies and malignant transformation.
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Wicker, Maria [Verfasser], Reinhard [Akademischer Betreuer] Schwinzer, and Christine Susanne [Akademischer Betreuer] Falk. "Untersuchungen zu den funktionellen Auswirkungen einer CD161-LLT1 Interaktion auf die NK- und T-Zellaktivierung / Maria Wicker ; Akademische Betreuer: Reinhard Schwinzer, Christine Susanne Falk ; Klinik für Allgemein-, Viszeral- und Transplantationschirurgie." Hannover : Bibliothek der Medizinischen Hochschule Hannover, 2018. http://d-nb.info/1173464344/34.

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Gomes, Fernando Vacilotto. "Reparo ósseo perimplantar após LLTC em coelhos : esteriologia e MEV." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/85097.

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Estudos prévios sugerem que a laserterapia de baixa potência (LLLT) favorece o reparo ósseo perimplantar. Este estudo avaliou a influência da LLLT sobre o reparo ósseo perimplantar in vivo em 32 coelhos Nova Zelândia submetidos à exodontia do incisivo inferior esquerdo imediatamente seguida pela inserção de um implante osseointegrável. Os animais foram distribuídos aleatoriamente em quatro grupos: um grupo controle C (animais não irradiados) e três experimentais. Estes receberam 7 sessões de terapia laser (AsGaAl, infravermelho, 830 ηm, 50mW, CW), com intervalos de 48 horas. A dose de laser por sessão variou entre os grupos EI (10 J/cm²), EII (5 J/cm²) e EIII (20J/cm²). Os animais foram mortos e os espécimes preparados histologicamente para análise da superfície de contato entre osso e implante (BIC) e da área de neoformação óssea entre as espiras (BA), em esteriologia e Microscopia Eletrônica de Varredura (MEV). A concentração de cálcio na interface do tecido ósseo com o implante foi analisada por espectrometria de raios-X por dispersão de energia (EDS). Os resultados foram analisados estatisticamente. Para MEV, as médias de BIC foram significativamente maiores para os grupos EI (977,9 μm) e EIII (1021,1 μm), comparados a EII (761,5 μm) e C (807,8 μm). Em BA, EIII (122573,7 μm²) superou os valores de neoformação dos demais grupos. O EDS para concentração de cálcio não apresentou diferença entre os grupos. A análise de BIC por meio de esteriologia mostrou valores significativamente maiores para EIII (1045,3 μm) em relação aos demais grupos. Para a BA, os grupos EI (100068,3 μm²) e EIII (103934,5 μm²) mostraram grandezas significativamente maiores. O uso da LLLT, no protocolo descrito, influenciou positivamente o reparo ósseo perimplantar com aumento do contato do tecido ósseo com o implante principalmente na dose de 20 J/cm² por sessão, bem como maior volume ósseo neoformado entre as espiras.
Previous studies suggest that the low level laser therapy (LLLT) has a favorable effect on perimplant bone healing. This study evaluates the LLLT influence over perimplant bone healing pattern in 32 New Zealand male rabbits which were subimitted to a lower incisor extraction followed by an osseointegrated implant immediated insertion. The animals were randomly divided into four groups of eight animals each: a control group C (non-irradiated animal) and three experimental groups. They received seven laser therapy sessions (GaAlAs, infrared, 830 nm, 50 mW, CW), every 48 hours. The LLLT per session dose ranged between the groups EI (dose – 10 J/cm²), EII (dose – 5 J/cm²) and EIII (dose – 20 J/cm²). The animals were killed and the specimens received histological preparation for bone implant contact analysis (BIC) and Bone Area evaluation (BA) among the implant threads, both steriology and Scanning Electron Microscopy (SEM). The calcium concentration in bone implant interface were analysed by Energy-Disperse X-Ray Spectroscopy (EDS). The results were statistically analyzed. For SEM results, the BIC’s mean were significantly higher for the irradiated groups EI (977,9 μm) and EIII (1021,1 μm) compared to EII (761,5 μm) and C (807,8 μm). For BA, EIII (122573,7 μm²) showed better values for bone neoformation compared to other groups. For EDS calcium concentration there was no significantly difference between groups. The steriology analysis showed significantly higher values for BIC in EIII (1045,3 μm) compared to the other groups. For BA, EI (100068,3 μm²) and EIII (103934,5 μm²) were significantly higher. In this laser protocol, the use of LLLT induced positively perimplantar bone repair specially due to the bone implant contact improvement (20 J/cm² per session dose), as well as, better bone area neoformation within treads.
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Klein, Stefan. "Neue Methoden zur Entdeckung von Fehlspezifikation bei Latent-Trait-Modellen der Veränderungsmessung." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2003. http://dx.doi.org/10.18452/14905.

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Ziel der Arbeit ist die Entwicklung von Modellen zur Entdeckung von Fehlspezifikation im Linear Logistic Test Model ( = LLTM) und verwandten Modellen der Verände\-rungs\-mes\-sung. Fehlspezifikation bedeutet hierbei, dass dem Modell ein unzutreffendes Muster latenter Traits zugrundegelegt wurde. Dies kann, vgl. z.B. [Baker,1993], zu bedeutenden Schätzfehlern führen. Die hier vorgestellten Methoden ermöglichen es unter leicht zu erfüllenden Annahmen, Aussagen über das Ausmaß der Unkorrektheit der verwendeten Modellspezifikation zu machen, ohne die in der Modellschätzung bestimmten Parameterwerte verwenden zu müssen. Zunächst wird eine auf dem Mantel-Haenszel-Test beruhende Methodik vorgestellt, die bei Tests bezüglich der Veränderungsparameter eines LLTMs als direkte Konkurrenz zu den bekannten Likelihood-Ratio-Tests für das LLTM anzusehen ist, wie sie z.B. bei [Fischer,1995a] vorgestellt werden. Weiterhin werden für das LLTM optimierte Personenfittests und daraus abgeleitete Effektgrößen vorgestellt. Diese ermöglichen das Auffinden von Subpopulationen, bei denen eine Abweichung zum angenommenen Modell aufgetreten ist. Es werden die statistischen Eigenschaften dieser Tests resp. Effektgrößen mittels Simulation und Teststärkeberechnung untersucht und Anwendungsbeispiele für diese Methoden vorgestellt.
In this thesis, new methods are developed for the detection of misspecification within Linear Logistic Test Models (=LLTM) and similar model classes for the measurement of change. The phrase "misspecification" will be used if a wrong selection of latent traits is chosen for the estimation of the LLTM. Misspecification can lead to erronious estimation [Baker,1993]). Using the newly developed methods, it is possible to measure the extent of deviations between the proposed model and the data. This can be done without using estimated parameter values. First a method is introduced which is based on the well-known Mantel-Haenszel-test. For some hypotheses, this method can be used instead of a Likelihood Ratio Test (e.g. [Fischer,1995a]). The Main topic of this thesis are uniformly most powerful tests for the measurement of person fit and related effect measures. These effect measures can be used for the identification of subpopulations where the proposed model does not hold. Statistical properties of these tests resp. effect measures are examined by simulations and power calculations using the SAS software. Furthermore, examples of the application of these methods are given.
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Mair, Patrick, and Reinhold Hatzinger. "Extended Rasch Modeling: The eRm Package for the Application of IRT Models in R." Department of Statistics and Mathematics, WU Vienna University of Economics and Business, 2007. http://epub.wu.ac.at/332/1/document.pdf.

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Item response theory models (IRT) are increasingly becoming established in social science research, particularly in the analysis of performance or attitudinal data in psychology, education, medicine, marketing and other fields where testing is relevant. We propose the R package eRm (extended Rasch modeling) for computing Rasch models and several extensions. A main characteristic of some IRT models, the Rasch model being the most prominent, concerns the separation of two kinds of parameters, one that describes qualities of the subject under investigation, and the other relates to qualities of the situation under which the response of a subject is observed. Using conditional maximum likelihood (CML) estimation both types of parameters may be estimated independently from each other. IRT models are well suited to cope with dichotomous and polytomous responses, where the response categories may be unordered as well as ordered. The incorporation of linear structures allows for modeling the effects of covariates and enables the analysis of repeated categorical measurements. The eRm package fits the following models: the Rasch model, the rating scale model (RSM), and the partial credit model (PCM) as well as linear reparameterizations through covariate structures like the linear logistic test model (LLTM), the linear rating scale model (LRSM), and the linear partial credit model (LPCM). We use an unitary, efficient CML approach to estimate the item parameters and their standard errors. Graphical and numeric tools for assessing goodness-of-fit are provided. (author's abstract)
Series: Research Report Series / Department of Statistics and Mathematics
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Boulant, Anthony. "Contribution à la caractérisation de poudres micro et nanostructurées de Li0,3La0,57 0,13TiO3 par RMN 1H et 7Li : importance de l'échange ionique Li+/H+." Le Mans, 2009. http://cyberdoc.univ-lemans.fr/theses/2009/2009LEMA1019.pdf.

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Ces travaux de thèse ont porté sur l'étude des propriétés des poudres micro et nanostructurées de Li0,3La0,57TiO3 (LLTO) vis-à-vis de l’air ambiant, en combinant les techniques suivantes : la diffraction des Rayons X, l’Analyse Thermo-Gravimétrique, la spectroscopie Infra-Rouge, et la RMN des noyaux 1H et 7Li. Les études sur le comportement du composé LLTO en milieu aqueux ont montré son instabilité vis-à-vis de l’échange ionique Li+/H+. Les ions lithium sortent de la structure perovskite pour être échangés par des protons venant de la dissociation de l’eau. La synthèse de poudre nanostructurée (méthode Pechini avec abaissement de la température de recuit) nous a permis d’observer, plus rapidement que sur les composés micrométriques synthétisés par voie solide, l’existence de ces mêmes sites de protons caractéristiques de sites de lithium échangés, prouvant la réactivité du matériau avec l’air ambiant. Les études dynamiques par mesures des temps de relaxation spin-réseau des noyaux 7Li et 1H ont également permis d’approfondir la compréhension des relations surface/volume dans les nano-matériaux. L’étude du vieillissement des poudres LLTO à l’air ambiant a démontré que l’échange ionique Li+/H+ avec la vapeur d’eau s’accompagne de la formation de carbonate de lithium, avec le dioxyde de carbone de l’air. Un traitement thermique à 400°C pendant deux heures permet de retrouver les caractéristiques du composé après synthèse, prouvant ainsi la réversibilité du processus de vieillissement. Les phases échangeables Li+/H+, dont LLTO fait parti, ont un important potentiel d’application pour le stockage du CO2
This thesis presents properties studies of nano and microstructurated powder Li0,3La0,57TiO3 (LLTO) against ambient air, using X Ray Diffraction, Thermo Gravimetric Analysis, Infra Red spectroscopy, 1H and 7Li NMR. Studies have evidenced the instability of LLTO sample toward water leading to ionic exchange Li+/H+. In aqueous solution, lithium ions come out from perovskite structure and are replaced by protons come from water dissociation. Nanostructured LLTO powder with Pechini way of synthesis allows to exhibit, quickly than for microstructurated sample, presence of such exchanged proton sites in sample after synthesis, proving its reactivity. Dynamical studies throught spin lattice relaxation time measurements of the 7Li and 1H nuclei also bring a deeper insight on the surface/volume relation in nanomaterials. Aged sample study with ambient air show that this instability toward water leads to formation of lithium carbonate with carbon dioxide from air. An thermal treatment at 400°C during 2 hours let the initial LLTO sample formation again, demonstrating the reversibility of aging process. All Li+/H+ exchangeable phases, which LLTO belongs, offer an important way of application for CO2 storage
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Nagler-Nitzschner, Ursa. "Development of a working memory test for the German Bundeswehr’s online assessment." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22529.

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Wie die meisten westlichen Streitkräfte, bewegt sich die Bundeswehr im Spannungsfeld zwischen hohem Personalbedarf und Fachkräftemangel. Durch ein Onlineassessment kann der Bewerbungsprozess dahingehend optimiert werden, dass fähiges Personal schneller gebunden wird. Onlineassessment hat diverse Vorteile, gleichzeitig sind damit jedoch Herausforderungen verbunden. Die wahrscheinlich größte ist es, Betrug zu minimieren, da Onlineassessment in einer weitestgehend unkontrollierten Umgebung stattfindet. Zur Entgegnung dieser Problematik dienen verschiedene Ansätze, wie beispielsweise große Itempools, wodurch einer Verbreitung der Lösung im Internet entgegengewirkt werden kann. Dieser Ansatz ist jedoch mit hohen Kosten verbunden. Automatische Itemgenerierung hingegen ermöglicht es, kostengünstig und zeiteffizient psychometrisch hochwertige Items zu erstellen. Aus diesem Grund wurden in der vorliegenden Arbeit zwei Arbeitsgedächtnistests mit automatischer Itemgenerierung für das Onlineassessment der Bundeswehr entwickelt und evaluiert, mit dem Ziel einer hohen prädiktiven Validität auf die Diagnostik vor Ort. In der ersten Studie (N = 330) wurde gezeigt, dass automatische Itemgenerierung für die entwickelten Arbeitsgedächtnistests eingesetzt werden kann. Hierbei wurden zudem zwei verschiedene zeitliche Varianten untersucht, wobei sich diejenige mit der längeren Stimulusrepräsentationszeit als vorteilhafter erwies. In der zweiten Studie (N = 621) wurden Nachweise für Reliabilität und Validität erbracht. Die Tests zeigten eine gute konvergente und diskriminante Validität. Zudem konnte einer der beiden Tests eine sehr gute prädiktive Validität aufweisen. Unter Gesamtberücksichtigung der Testgütekriterien wurde dieser Test schließlich für das Onlineassessment der Bundeswehr vorgeschlagen. Somit steht der Bundeswehr nun ein wissenschaftlich fundierter Arbeitsgedächtnistest für das Onlineassessment zur Verfügung.
Like most Western armed forces, the Bundeswehr faces both high personnel requirements and a shortage of skilled personnel. Online assessment can optimize the application process to ensure that capable personnel are retained more quickly. Online assessment has various advantages, but also challenges associated with it. Probably the biggest of these challenges is minimizing cheating, as online assessment takes place in a largely unsupervised environment. Various approaches are used to counter this problem, such as large item pools, which can be used to counter the dissemination of solutions on the Internet. However, this approach is associated with high costs. Automatic item generation, on the other hand, makes it possible to create psychometrically high-quality items in a cost-effective and time-efficient manner. For this reason, two working memory tests with automatic item generation for the German Armed Forces’ online assessment were developed and evaluated in the present study, with the aim of matching the high predictive validity of on-site diagnostics. The first study (N = 330) demonstrated that automatic item generation can be used for the developed working memory tests. Two different temporal variants were also investigated, with the longer stimulus presentation time proving to be more beneficial. The second study (N = 621) provided reliability and validity evidence. The tests showed good convergent and discriminant validity. In addition, one of the two tests demonstrated very good predictive validity. Taking into account the overall test quality criteria, this test was ultimately proposed for use in the German Armed Forces’ online assessment. Thus, the Bundeswehr now has a scientifically-grounded working memory test available for its online assessment.
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Roffat, Michaël. "Synthèse de titanate de lithium et de lanthane (LLTO) pour la réalisation de couches minces et épaisses : application à la réalisation de microélectrodes totalement solides pour la détection du pH." Le Mans, 2009. http://cyberdoc.univ-lemans.fr/theses/2009/2009LEMA1017.pdf.

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L'enjeu de ce travail de thèse a été de réaliser des couches minces puis des couches épaisses non poreuses du titanate de lithium et de lanthane de formule Li3xLa2/3-xTiO3 (LLTO). Ce composé est l'un des meilleurs conducteurs ioniques solides connus actuellement. Sa conductivité, σ = 10-3 S cm-1 à 25 °C, est assurée essentiellement par les ions Li+. Pour ce faire, il a été nécessaire de choisir et de mettre au point une méthode de synthèse de chimie en solution afin de pouvoir réaliser des films sur un substrat approprié. La méthode EISA (Evaporation Induced Self-Assembly) a été utilisée, mais les films (250 nm) sont très poreux et pourraient trouver une application pour des capteurs de gaz. Pour l'application capteurs de pH ou électrode de référence, des films denses sont nécessaires. Pour les obtenir, le procédé DATEC a été employé. Les films sont réalisés à partir d'une solution composite formée des poudres céramiques dans une solution sol-gel des précurseurs. Des couches denses de LLTO de plusieurs microns ont pu être obtenues. Ces matériaux s'avèrent très intéressants en tant qu'électrode de référence totalement solide
The thesis challenge was based first on the realization of thin coatings, then of thick and no porous coatings of lithium lanthanum titanates of the series Li3xLa2/3-xTiO3 (LLTO). This oxide is a fast Li+ conductor with an ionic conductivity of σ = 10-3 S cm-1 at 25 °C. At first, a solution chemistry synthesis was chosen and developed to prepare coatings of LLTO on an appropriated wafer. The EISA (Evaporation Induced Self-Assembly) method was used, but these coatings (250 nm) are very porous and could find an application for gas sensors. For pH sensors or reference electrode applications, thick and non porous coatings are required. The DATEC process was used in this context. These films were realized with a slurry composition having ceramic powders and precursors sol-gel solution. LLTO thick coatings (10 μm) were obtained. These new materials are very interesting for an all-solid-state reference electrode
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Hatzinger, Reinhold. "A GLM framework for item response theory models. Reissue of 1994 Habilitation thesis." Department of Statistics and Mathematics, WU Vienna University of Economics and Business, 2008. http://epub.wu.ac.at/1384/1/document.pdf.

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The aim of the monograph is to contribute towards bridging the gap between methodological developments that have evolved in the social sciences, in particular in psychometric research, and methods of statistical modelling in a more general framework. The first part surveys certain special psychometric models (often referred to as Rasch family of models) that share common properties: separation of parameters describing qualities of the subject under investigation and parameters related to properties of the situation under which the response of a subject is observed. Using conditional maximum likelihood estimation, both types of parameters may be estimated independently from each other. In particular, the Rasch model, the rating scale model, the partial credit model, hybrid types, and linear extensions thereof are treated. The second part reviews basic ideas of generalized linear models (GLMs) as an an excellent framework for unifying different approaches and providing a natural, technical background for model formulation, estimation and testing. This is followed by a short introduction to the software package GLIM chosen to illustrate the formulation of psychometric models in the GLM framework. The third part is the main part of this monograph and shows the application of generalized linear models to psychometric approaches. It gives a unified treatment of Rasch family models in the context of log-linear models and contains some new material on log-linear longitudinal modelling. The last part of the monograph is devoted to show the usefulness of the latent variable approach in a variety of applications, such as panel, cross-over, and therapy evaluation studies, where standard statistical analysis does not necessarily lead to satisfactory results. (author´s abstract)
Series: Research Report Series / Department of Statistics and Mathematics
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Abramova, Alla. "Elaboration par chimie douce, mise en forme et propriétés électriques de conducteurs ioniques nanostructurés." Thesis, Le Mans, 2014. http://www.theses.fr/2014LEMA1025/document.

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Le but de ce travail de thèse, effectué dans le cadre du programme Européen IRSES « Nanolicom », était d’étudier l’influence de la nanostructuration sur les propriétés de transport de deux matériaux conducteurs par les ions lithium, la pérovskite LLTO (Li0.3La0.57TiO3) et le nasicon LATPO (Li1.3Al0.3Ti1.7(PO4)3).Une première partie importante de cette thèse a été consacrée à l’exploration et au développement de méthodes de synthèse par chimie douce plus favorables à la préparation de poudres nanométriques : la voie sol-gel, la voie des complexes polymérisables, la synthèse hydro-solvothermale et la réalisation de microémulsions. Les matériaux obtenusont ensuite été caractérisés par diffraction des rayons X, analyses thermiques et microscopies électroniques.La mise en forme des échantillons ainsi que leur densification ont également fait l’objet d’une étude approfondie. En effet, la détermination des propriétés de transport des matériaux nécessite l’utilisation de céramiques denses mais il est difficile de conserver le caractère nanostructuré des poudres lors de l’étape de frittage. Finalement, les mesures de conductivitésioniques ont été réalisées par spectroscopie d’impédance. L’ensemble des résultats obtenus a ensuite été comparé à ce qui a déjà été observé et reporté dans la littérature pour les composés microstructurés de même formulation
The aim of this thesis, which has been carried out within the European program « Nanolicom », was to study the influence of the nanostructuration on the transport properties of two lithium ionic conductors, the perovskite LLTO (Li0.3La0.57TiO3) and the nasicon LATPO (Li1.3Al0.3Ti1.7(PO4)3).The first part of this thesis is devoted to the exploration and to the optimization of the best soft chemistry route in order to get nanometric powders: sol-gel route, hydro-solvothermal synthesis, reversed microemulsion method and complex polymerizable Pechini method. The obtained materials were characterized by X-ray diffraction, thermal analysis andelectronic microscopy. Shaping and sintering of the samples were also thoroughly studied. Indeed, the determination of transport properties of the materials requires the use of dense ceramics but it is difficult to preserve the nanostructured character of the powders during the sintering step. Finally, the ionic conductivity measurements were carried out by compleximpedance spectroscopy. All results were then compared to what has been observed and reported in the literature for microstructured compounds of the same formulation
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Books on the topic "LLT1"

1

Merz, Konrad. Ein mensch fa llt aus Deutschland. Berlin: Aufbau-Verlag, 1994.

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Ackroyd, Peter. Wie es uns gefa llt: Roman. Mu nchen: Knaus, 2007.

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Training of Trainers Course (6th 1988-1989 Centre for Water Resources, Anna University). Sixth Training of Traieers [i.e. Trainers] Course, 19th Dec., 1988-llth Feb., 1989. Madras: The Centre, 1989.

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Soeder, Sonja. Ganz Frau!: Ihr Beckenboden-Buch fu r erfu llte Sexualita t und Kontinenz. Stuttgart: TRIAS, 2010.

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Weiner, Christine. Das Pippilotta-Prinzip: Ich mach mir die Welt, wie sie mir gefa llt. Frankfurt/Main [u.a.]: Campus-Verl., 2006.

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1916-, Sawaragi Yoshikazu, Sagara S, and International Federation of Automatic Control., eds. System identification (SYSIDʼ97): A proceedings volume from the llth IFAC symposium, Kitakyushu, Fukuoka, Japan, 8-11 July 1997. New York: Published for the International Federation of Automatic Control by Pergamon, 1998.

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Nuzzi, Gianluigi. Vatikan AG: Ein Geheimarchiv enthu˜llt die Wahrheit u˜ber die Finanz- und Politskandale der Kirche. Salzburg: Ecowin Verlag, 2010.

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Lauwers, Bernard. De Britse opmars van Normandië naar Antwerpen 1944: De bevrijding van de stad en de haven door de llth. Armoured Division. Antwerpen: C. de Vries-Brouwers, 1987.

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Elliott, Tony. Ysgol EdmwndPrys, Gellilydan, Blaenau Ffestiniog, Gwynedd, LL41 4DY: Arolygiad dan Adran 9 o Ddeddf Addysg (Ygolion) 1992 : rhif ysgol 573/2192 : dyddiad arolygiad 11.03.96-14.03.96. (Cardiff): (Welsh Office), 1996.

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Davies, L. J. Ysgol Dinmael, Dinmael, Corwen, Sir Ddinbych LL21 0PP: Arolygiad dan Adran 10 o Ddeddf Arolygu Ysgolion 1996 : rhif yr ysgol: 662/2119 : dyddiad yr arolygiad: 12-14 Ionawr, 2004 = Ysgol Dinmael, Dinmael, Corwen, Denbighshire LL21 0PP : inspection under Section 10 Inspection of Schools Act 1996 : school number: 662/2119 : date of inspection: 12-14 January, 2004. Cardiff: Estyn, 2004.

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Book chapters on the topic "LLT1"

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Fischer, Gerhard H., and Norbert Tanzer. "Some LBTL and LLTM Relationships." In Recent Research in Psychology, 277–303. New York, NY: Springer New York, 1994. http://dx.doi.org/10.1007/978-1-4612-4308-3_21.

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Jeon, Minjeong, Karen Draney, and Mark Wilson. "A General Saltus LLTM-R for Cognitive Assessments." In Quantitative Psychology Research, 73–90. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-07503-7_5.

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Gebhardt, Wolfgang, and Friedhelm Walte. "Crack Detection and Defect Classification Using the LLT-Technique." In Review of Progress in Quantitative Nondestructive Evaluation, 591–98. Boston, MA: Springer US, 1989. http://dx.doi.org/10.1007/978-1-4613-0817-1_74.

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Koschny, Detlef, Jorge Diaz Del Rio, Rodrigue Piberne, Marek Szumlas, Joe Zender, and André Knöfel. "Radiants of the Leonids 1999 and 2001 Obtained by LLTV Systems Using Automatic Software Tools." In Modern Meteor Science An Interdisciplinary View, 255–63. Dordrecht: Springer Netherlands, 2005. http://dx.doi.org/10.1007/1-4020-5075-5_27.

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"llth." In Handbook of Applied Economic Statistics, 178–96. CRC Press, 1998. http://dx.doi.org/10.1201/9781482269901-27.

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McWilliam, Andrew, and Elizabeth G. Traube. "Land and Life in Timor-Leste: Introduction." In Land and Life in Timor-Leste: Ethnographic Essays. ANU Press, 2011. http://dx.doi.org/10.22459/lltl.12.2011.01.

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Barnes, Susana. "Origins, Precedence and Social Order in the Domain of Ina Ama Beli Darlari." In Land and Life in Timor-Leste: Ethnographic Essays. ANU Press, 2011. http://dx.doi.org/10.22459/lltl.12.2011.02.

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Bovensiepen, –. Judith. "Opening and Closing the Land: Land and power in the Idaté highlands." In Land and Life in Timor-Leste: Ethnographic Essays. ANU Press, 2011. http://dx.doi.org/10.22459/lltl.12.2011.03.

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McWilliam, Andrew. "Fataluku Living Landscapes." In Land and Life in Timor-Leste: Ethnographic Essays. ANU Press, 2011. http://dx.doi.org/10.22459/lltl.12.2011.04.

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Molnar, Andrea K. "Darlau: Origins and their significance for Atsabe Kemak identity." In Land and Life in Timor-Leste: Ethnographic Essays. ANU Press, 2011. http://dx.doi.org/10.22459/lltl.12.2011.05.

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Conference papers on the topic "LLT1"

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Barbier, Charlotte, and Joseph A. C. Humphrey. "Numerical Calculation of the Flow in the Fish Lateral Line Canal: Applications to Predators Tracking Prey." In ASME 2006 International Mechanical Engineering Congress and Exposition. ASMEDC, 2006. http://dx.doi.org/10.1115/imece2006-14165.

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Fish use sensors inside the lateral line trunk canal (LLTC) to detect the motion of water in their surroundings. The LLTC is a complex sensory organ consisting of a long tube no more than a few millimeters in diameter embedded immediately under the skin of the fish on each side of its body. In most fish, pore-like openings are regularly distributed along the LLTC, and a minute sensor enveloped in a gelatinous cupula, referred to as a neuromast, is located between each pair of pores. Drag forces resulting from fluid motions induced inside the LLTC by pressure fluctuations in the external flow stimulate the neuromasts. The present study investigates the motion-sensing characteristics of the LLTC and how it may be used by fish to track prey. A two-level numerical model is presented that couples the surrounding flow outside the LLTC to that stimulating the neuromasts within it. First the unsteady flow past a pair of simulated prey/predator fish in coasting motion is calculated using a Navier-Stokes solver. Then the pressure field associated with this external flow is used to drive the flow inside the LLTC of the predator, which creates the drag forces acting on the neuromast. The model is used to investigate the filtering properties and performance characteristics of the LLTC for a range of unsteady flows of biological interest. The results obtained suggest that the LLTC preferentially filters high frequency pressure gradient oscillations, and hence high frequency accelerations, associated with the external flow.
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Olesnavage, Kathryn M., and Amos G. Winter. "Passive Prosthetic Foot Shape and Size Optimization Using Lower Leg Trajectory Error." In ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/detc2017-67618.

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A method is presented to optimize the shape and size of a passive prosthetic foot using the Lower Leg Trajectory Error (LLTE) as the design objective. The LLTE is defined as the root-mean-square error between the lower leg trajectory calculated for a given prosthetic foot by finding the deformed shape of the foot under typical ground reaction forces and a target physiological lower leg trajectory obtained from published gait data for able-bodied walking. In previous work, the design of simple two degree-of-freedom analytical models consisting of rigid structures, rotational joints with constant stiffness, and uniform cantilevered beams, have been optimized for LLTE. However, prototypes built to replicate these simple models were large, heavy, and overly complex. In this work, the size and shape of a single-part compliant prosthetic foot keel made out of nylon 6/6 was optimized for LLTE to produce a light weight, low cost, and easily manufacturable prosthetic foot design. The shape of the keel was parameterized as a wide Bézier curve, with constraints ensuring that only physically meaningful shapes were considered. The LLTE value for each design was evaluated using a custom MATLAB script, which ran ADINA finite element analysis software to find the deformed shape of the prosthetic keel under multiple loading scenarios. The optimization was performed by MATLAB’s built-in genetic algorithm. After the optimal design for the keel was found, a heel was added to structure, sized such that when the user’s full weight acted on the heel, the structure had a factor of safety of two. The resulting optimal design has a lower LLTE value than the two degree-of-freedom analytical models, at 0.154 compared to 0.172, 0.187, and 0.269 for the two degree-of-freedom models. At 412 g, the optimal wide curve foot is nearly half the mass of the lightest prototype built from the previous models, which was 980 g. The design found through this compliant mechanism optimization method is thus far superior to the two degree-of-freedom models previously considered.
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Prost, Victor, Kathryn M. Olesnavage, and Amos G. Winter. "Design and Testing of a Prosthetic Foot Prototype With Interchangeable Custom Rotational Springs to Adjust Ankle Stiffness for Evaluating Lower Leg Trajectory Error, an Optimization Metric for Prosthetic Feet." In ASME 2017 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/detc2017-67820.

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A prosthetic foot prototype intended for evaluating a novel design objective for passive prosthetic feet, the Lower Leg Trajectory Error (LLTE), is presented. This metric enables the optimization of prosthetic feet by modeling the trajectory of the lower leg segment throughout a step for a given prosthetic foot and selecting design variables to minimize the error between this trajectory and target physiological lower leg kinematics. Thus far, previous work on the LLTE has mainly focused on optimizing conceptual foot architectures. To further study this metric, extensive clinical testing on prototypes optimized using this method has to be performed. Initial prototypes replicating the LLTE-optimal designs in previous work were optimized and built, but at 1.3 to 2.1 kg they proved too heavy and bulky to be considered for testing. A new, fully-characterized foot design reducing the weight of the final prototype while enabling ankle stiffness to be varied is presented and optimized for LLTE. The novel merits of this foot are that it can replicate a similar quasi-stiffness and range of motion of a physiological ankle, and be tested with variable ankle stiffnesses to test their effect on LLTE. The foot consists of a rotational ankle joint with interchangeable U-shaped constant stiffness springs ranging from 1.5 Nm/deg to 16 Nm/deg, a rigid structure extending 0.093 m from the ankle-knee axis, and a cantilever beam forefoot with a bending stiffness of 16 Nm2. The prototype was built using machined acetal resin for the rigid structure, custom nylon springs for the ankle, and a nylon beam forefoot. In preliminary testing, this design performed as predicted and its modularity allowed us to rapidly change the springs to vary the ankle stiffness of the foot. Qualitative feedback from preliminary testing showed that this design is ready to be used in larger-scale studies. In future work, extensive clinical studies with testing different ankle stiffnesses will be conducted to validate the optimization method using the LLTE as a design objective.
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Marten, David, Matthew Lennie, Georgios Pechlivanoglou, Christian Navid Nayeri, and Christian Oliver Paschereit. "Implementation, Optimization and Validation of a Nonlinear Lifting Line Free Vortex Wake Module Within the Wind Turbine Simulation Code QBlade." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43265.

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The development of the next generation of large multi-megawatt wind turbines presents exceptional challenges to the applied aerodynamic design tools. Because their operation is often outside the validated range of current state of the art momentum balance models, there is a demand for more sophisticated, but still computationally efficient simulation methods. In contrast to the Blade Element Momentum Method (BEM) the Lifting Line Theory (LLT) models the wake explicitly by a shedding of vortex rings. The wake model of freely convecting vortex rings induces a time-accurate velocity field, as opposed to the annular averaged induction that is computed from the momentum balance, with computational costs being magnitudes smaller than those of a full CFD simulation. The open source code QBlade, developed at the Berlin Institute of Technology, was recently extended with a Lifting Line - Free Vortex Wake algorithm. The main motivation for the implementation of a LLT algorithm into QBlade is to replace the unsteady BEM code AeroDyn in the coupling to FAST to achieve a more accurate representation of the unsteady aerodynamics and to gain more information on the evolving rotor wake and flow-field structure. Therefore, optimization for computational efficiency was a priority during the integration and the provisions that were taken will be presented in short. The implemented LLT algorithm is thoroughly validated against other benchmark BEM, LLT and panel method codes and experimental data from the MEXICO and NREL Phase VI tests campaigns. By integration of a validated LLT code within QBlade and its database, the setup and simulation of LLT simulations is greatly facilitated. Simulations can be run from already existing rotor models without any additional input. Example use cases envisaged for the LLT code include; providing an estimate of the error margin of lower fidelity codes i.e. unsteady BEM, or providing a baseline solution to check the soundness of higher fidelity CFD simulations or experimental results.
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Olesnavage, Kathryn M., and Amos G. Winter. "Design and Preliminary Testing of a Prototype for Evaluating Lower Leg Trajectory Error as an Optimization Metric for Prosthetic Feet." In ASME 2016 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/detc2016-60565.

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This work presents the design and preliminary testing of a prosthetic foot prototype intended for evaluating a novel design objective for passive prosthetic feet, the Lower Leg Trajectory Error (LLTE). Thus far, all work regarding LLTE has been purely theoretical. The next step is to perform extensive clinical testing. An initial prototype consisting of rotational ankle and metatarsal joints with constant rotational stiffness was optimized and built, but at 2 kg it proved too heavy to use in clinical testing. A new conceptual foot architecture intended to reduce the weight of the final prototype is presented and optimized for LLTE. This foot consists of a rotational ankle joint with constant stiffness of 6.1 N·m/deg, a rigid structure extending 0.08 m from the ankle-knee axis, and a cantilever beam forefoot with bending stiffness 5.4 N·m2. A prototype was built using machined delrin for the rigid structure, three parallel extension springs offset along a constant radius cam from a pin joint ankle, and machined nylon as the beam forefoot. In preliminary testing, it was determined that, despite efforts to minimize weight and size, this particular design was still too heavy and bulky as a result of the extension springs to be used in extensive clinical testing. Future work will focus on reducing the weight further by replacing linear extension springs with flexural elements before commencing with the clinical study.
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Zhang, Yonghong, and Xueming Xu. "LLT-EMD algorithm based on wavelet packets." In 2011 4th International Congress on Image and Signal Processing (CISP). IEEE, 2011. http://dx.doi.org/10.1109/cisp.2011.6100683.

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Palmieri, Beniamino, Stefania Capone, and Leonardo Longo. "Biosensors Related LLT: Physiopathology, Background and Rationale." In ADVANCES IN LASEROLOGY - SELECTED PAPERS OF LASER FLORENCE 2010: The 50th Birthday of Laser Medicine World. AIP, 2011. http://dx.doi.org/10.1063/1.3626925.

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Hamid Mehdi. "Mobility prediction with LLT algorithm in wireless networks." In 2010 International Conference on Information, Networking and Automation (ICINA 2010). IEEE, 2010. http://dx.doi.org/10.1109/icina.2010.5636973.

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Xu, Hongzhi, Enrico Santus, Anna Laszlo, and Chu-Ren Huang. "LLT-PolyU: Identifying Sentiment Intensity in Ironic Tweets." In Proceedings of the 9th International Workshop on Semantic Evaluation (SemEval 2015). Stroudsburg, PA, USA: Association for Computational Linguistics, 2015. http://dx.doi.org/10.18653/v1/s15-2113.

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Militzer, Michael, Maciej Suchomski, and Klaus Meyer-Wegener. "LLV1: layered lossless video format supporting multimedia servers during realtime delivery." In Optics East 2005, edited by Anthony Vetro, Chang Wen Chen, C. C. J. Kuo, Tong Zhang, Qi Tian, and John R. Smith. SPIE, 2005. http://dx.doi.org/10.1117/12.631170.

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Reports on the topic "LLT1"

1

Halpern, J. M. OSI CLNS and LLC1 protocols on Network Systems HYPERchannel. RFC Editor, May 1991. http://dx.doi.org/10.17487/rfc1223.

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Lester, Peter F., and Mark W. Burton. Development of Low-Level Turbulence (LLT) Forecasting Methodologies. Fort Belvoir, VA: Defense Technical Information Center, December 1988. http://dx.doi.org/10.21236/ada208457.

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