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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

PPP引入对城市规划与建设影响的研究

January 2019 (has links)
abstract: 近些年来,我国城市化进程不断加快,到2020年我国常住人口城镇化率将达到60%左右,户籍人口城镇化率将会达到45%左右。伴随着我国城市化进程的高速推进以及经济水平的不断提高,公共物品及服务的需求程度加大,政府单独出资建设公共项目会导致资金不足、经营管理效率低下等问题。与此同时,我国当前不同层级地方政府的政府性债务都达到了一个非常高的水平,截至2017年末,中国地方政府债务16.47万亿元,债务率(债务余额/综合财力)为76.5%,其中地方负有偿还责任的债务约12.9万亿,地方政府性债务的控制和转化成为经济新常态下重要特征之一。在地方债务压力较大的情况下,PPP将替代土地财政和地方政府融资,为我国新型城镇化建设提供可持续的资金支持,PPP模式成为当前城市建设领域融资的重要选项。 据此,本文基于实证研究方法探讨在债务约束的背景下,在地方政府债务约束下,PPP模式的引入,对城市规划中建设用地面积、人口规划规模与容量、建设用地属性等的城市规划变量的影响;与此同时,考虑到地方政府的政策很大程度上受到是由地方官员,特别是受到作为地方政府党政“一把手”的市委书记和市长的晋升压力和激励的影响,讨论市委书记/市长的晋升压力和激励对PPP模式引入效果的影响。研究发现,在地方政府债务约束下,PPP模式的引入,显著增加城市规划中建设用地面积、人口规划规模与容量、建设用地属性等的城市规划变量;同时,地方政府官员存在利用PPP放大城市建设和规划规模的行为,反映了PPP项目在引入和使用的过程中很大程度上受政府官员的激励的影响。 / Dissertation/Thesis / Doctoral Dissertation Business Administration 2019
12

Extent, Correlates, and Consequences of Careless and Inattentive Responding in Certification Job Analysis Surveys

Muenzen, Patricia M 01 January 2019 (has links)
Survey data quality is influenced by the care and attention that respondents take in answering questions. Careless and inattentive (CI) responding is a confound in survey data that can distort findings and lead to incorrect conclusions. This quantitative study explored CI responding in job analysis studies supporting occupational certification programs and its relationship to survey features, data quality measures, and test content validity. Satisficing theory served as the framework, and secondary analysis of 3 job analysis surveys was undertaken. Results indicated that 9-33% of respondents engaged in CI responding, with the rate differing by CI index used (Mahalanobis distance, long string analysis, or person-total correlation) and by occupation. Each index detected a distinct pattern of carelessness, supporting the use of multiple indices. The indices performed best detecting carelessness in frequency ratings and may not be useful for all job analysis rating scales. Partial support was found for relationships between carelessness and survey features. CI responding had a minimal impact on mean ratings, correlations, and interrater reliability, and had no impact on certification test content outlines. By providing guidance and caution on the use of CI response detection methods with job analysis survey data, this study produced two potential avenues for social change. For practitioners conducting occupational job analyses, the use of CI detection methods can enhance the validity of data used to make certification decisions. For researchers, follow-up studies can yield a more nuanced understanding of the most appropriate use of these methods in the job analysis context.
13

Usefulness of breath-hold inversion recovery-prepared T1-weighted two-dimensional gradient echo sequence for detection of hepatocellular carcinoma in Gd-EOB-DTPA-enhanced MR imaging / Gd-EOB-DTPA造影MRIにおける肝細胞癌検出の向上;反転パルスを用いた呼吸停止下2次元T1強調グラディエントエコーシークエンスの有用性の検討

Ohno, Tsuyoshi 23 January 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20083号 / 医博第4176号 / 新制||医||1018(附属図書館) / 33199 / 京都大学大学院医学研究科医学専攻 / (主査)教授 増永 慎一郎, 教授 妹尾 浩, 教授 松田 道行 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
14

What Are You Looking At? Using Eye-Tracking to Provide Insight into Careless Responding.

Brower, Cheyna Katherine 03 June 2020 (has links)
No description available.
15

Investigating the Efficacy of Novel Measures of Careless Responding to Tests

Ramsey, Mark Christopher 12 August 2022 (has links)
No description available.
16

Semi-supervised Ensemble Learning Methods for Enhanced Prognostics and Health Management

Shi, Zhe 15 May 2018 (has links)
No description available.
17

Data-driven X-ray Tomographic Imaging and Applications to 4D Material Characterization

Wu, Ziling 05 January 2021 (has links)
X-ray tomography is an imaging technique to inspect objects' internal structures with externally measured data by X-ray radiation non-destructively. However, there are concerns about X-ray radiation damage and tomographic acquisition speed in real-life applications. Strategies with insufficient measurements, such as measurements with insufficient dosage (low-dose) and measurements with insufficient projection angles (sparse-view), have been proposed to relieve these problems but are generally compromising imaging quality. Such a dilemma inspires the development of advanced tomographic imaging techniques, in particular, deep learning algorithms to improve reconstruction results with insufficient measurements. The overall aim of this thesis is to design efficient and robust data-driven algorithms with the help of prior knowledge from physics insights and measurement models. We first introduce a hierarchical synthesis CNN (HSCNN), which is a knowledge-incorporated data-driven tomographic reconstruction method for sparse-view and low-dose tomography with a split-and-synthesis approach. This proposed learning-based method informs the forward model biases based on data-driven learning but with reduced training data. The learning scheme is robust against sampling bias and aberrations introduced in the forward modeling. High-fidelity X-ray tomographic imaging reconstruction results are obtained with a very sparse number of projection angles for both numerical simulated and physics experiments. Comparison with both conventional non-learning-based algorithms and advanced learning-based approaches shows improved accuracy and reduced training data size. As a result of the split-and-synthesis strategy, the trained network could be transferable to new cases. We then present a deep learning-based enhancement method, HDrec (hybrid-dose reconstruction algorithm), for low-dose tomography reconstruction via a hybrid-dose acquisition strategy composed of textit{extremely sparse-view normal-dose measurements} and textit{full-view low-dose measurements}. The training is applied for each individual sample without the need of transferring the trained models for other samples. Evaluation of two experimental datasets under different hybrid-dose acquisition conditions shows significantly improved structural details and reduced noise levels compared to results with traditional analytical and regularization-based iterative reconstruction methods from uniform acquisitions under the same amount of total dosage. Our proposed approach is also more efficient in terms of single projection denoising and single image reconstruction. In addition, we provide a strategy to distribute dosage smartly with improved reconstruction quality. When the total dosage is limited, the strategy of combining a very few numbers of normal-dose projections and with not-too-low full-view low-dose measurements greatly outperforms the uniform distribution of the dosage throughout all projections. We finally apply the proposed data-driven X-ray tomographic imaging reconstruction techniques, HSCNN and HDrec, to the dynamic damage/defect characterization applications for the cellular materials and binder jetting additive manufacturing. These proposed algorithms improve data acquisition speeds to record internal dynamic structure changes. A quantitative comprehensive framework is proposed to study the dynamic internal behaviors of cellular structure, which contains four modules: (i) In-situ fast synchrotron X-ray tomography, which enables collection of 3D microstructure in a macroscopic volume; (ii) Automated 3D damage features detection to recognize damage behaviors in different scales; (iii) Quantitative 3D structural analysis of the cellular microstructure, by which key morphological descriptors of the structure are extracted and quantified; (iv) Automated multi-scale damage structure analysis, which provides a quantitative understanding of damage behaviors. In terms of binder jetting materials, we show a pathway toward the efficient acquisition of holistic defect information and robust morphological representation through the integration of (i) fast tomography algorithms, (ii) 3D morphological analysis, and (iii) machine learning-based big data analysis. The applications to two different 4D material characterization demonstrate the advantages of these proposed tomographic imaging techniques and provide quantitative insights into the global evolution of damage/defect beyond qualitative human observation. / Doctor of Philosophy / X-ray tomography is a nondestructive imaging technique to visualize interior structures of non-transparent objects, which has been widely applied to resolve implicit 3D structures, such as human organs and tissues for clinical diagnosis, contents of baggage for security check, internal defect evolution during additive manufacturing, observing fracturing accompanying mechanical tests, and etc. Multiple planar measurements with sufficient X-ray exposure time among different angles are desirable to reconstruct the unique high-quality 3D internal distribution. However, there are practical concerns about X-ray radiation damage to biology samples or long-time acquisition for dynamic experiments in real-life applications. Insufficient measurements by reducing the number of total measurements or the time for each measurement, are proposed to solve this problem but doing so usually leads to the sacrifice of the reconstruction quality. Computational algorithms are developed for tomographic imaging under these insufficient measurement conditions to obtain reconstructions with improved quality. Deep learning has been successfully applied to numerous areas, such as in recognizing speech, translating languages, detecting objects, and etc. It has also been applied to X-ray tomographic imaging to improve the reconstruction results by learning the features through thousands to millions of corrupted and ideal reconstruction pairs. The aim of this thesis to design efficient deep learning-based algorithms with the help of physical and measurement priors to reduce the number of training datasets. We propose two different deep learning-based tomographic imaging techniques to improve reconstruction results with reduced training data under different insufficient measurement conditions. One way is to incorporate prior knowledge of the physics models to reduce the required amount of ground truth data, from thousands to hundreds. The training data requirement is further simplified with another hybrid measurement strategy, which could be implemented on each individual sample with only several high-quality measurements. In the end, we apply these two proposed algorithms to different dynamic damage/defect behavior characterization applications. Our methods achieve improved reconstruction results with greatly enhanced experimental speeds, which become suitable for dynamic 3D recording. Final results demonstrate the advantages of the proposed tomographic imaging techniques and provide quantitative insights into the global dynamic evolution inside the material. This quantitative analysis also provides a much more comprehensive understanding than qualitative human observation.
18

Peronalbristens påverkan på säkerhetskulturen i flygunderhållsorganisationer

Söderlund, Axel January 2019 (has links)
En god säkerhetskultur är avgörande för att flygunderhållsfunktionerna i Försvarsmakten ska kunna leverera luftvärdiga flygfarkoster. Personalbrist råder i flygunderhållsfunktionerna och därför undersöks om och hur personalbristen inverkar på säkerhetskulturen. I arbetet undersöks flygunderhållsfunktionen på en skvadron inom Helikopterflottiljen. På grund av att Försvarsmakten ålägger ansvaret för säkerhetskulturen på chefer i organisationen samt att forskning på ämnet pekar på att ledarskapet är den största inverkande faktorn på säkerhetskultur så undersöktes ämnet utifrån ett ledarskapsperspektiv. Fyra chefer från flygunderhållet på Helikopterflottiljen intervjuades om faktorer som påverkar säkerhetskulturen och om personalbristen i deras organisation. Slutsatserna i arbetet är att personalbristen bland chefer leder till att chefer inte har tillräckligt med tid för att planera arbetsuppgifter och svårigheter med att visa närvaro i hangarerna. En medvetenhet om personalbristen i organisationen leder till att chefer engagerar sig mycket i personalens välmående. Personalbristen bland tekniker leder till, i kombination med två andra faktorer, att rapporteringskulturen försämrats. / Safety culture is a critical factor within aircraft maintenance organizations for delivering air-worthy aircrafts for the Swedish Armed Forces. There is a problem with insufficient manpower within the aircraft maintenance organizations, and therefore this paper aims to examine the implications this might have on safety culture. An aircraft maintenance function within the Armed Forces Helicopter wing was studied. The Swedish Armed Forces regulations inflict the responsibility for safety culture upon commanding officers. And this together with the research on the subject safety culture that says that it is leadership that inflicts on safety culture the most, dictates this paper to examine the subject from a leadership point of view. Four officers from the aircraft maintenance function was interviewed about leadership factor that inflicts with safety culture and the insufficient manpower problems. This paper concludes that commanding officers have problem finding time for planning for the workforce and making frequent tours in the hangars. Due to awareness of the problems with insufficient manpower commanding officers pay extra attention to the workforce’s wellbeing. Due to lack of manpower within the workforce, together with two other factors, the reporting culture has declined.
19

Perímetro cefálico de crianças das populações remanescentes dos quilombos do estado de Alagoas, segundo adequação estatural, peso ao nascer e exposição ao aleitamento materno. / Head circumference of children from remnant Quilombolas populations of the state of Alagoas according to adequaty linear growth birth weight and expose to brestfeeding.

Xavier Júnior, Antonio Fernando Silva 04 December 2009 (has links)
Objective: The aim of this study was to investigate if the head circumference of stunted quilombolas children differs from that other children with adequate linear growth and if the insufficient birth weight and exclusive breastfeeding in the first month of life intervene with this relation. Methods: The work followed a transversal studying involving all the children of 12 to 60 months (n=725) pertaining to the quilombolas community of Alagoas (n=39). Variables demographics, socioeconomics, of the health and anthropometrics indices had been collected. These had been compared with the curves of the standard of reference of the of WHO 2006. The children had been categorized into two groups in agreement with the presence or not of the malnutrition (stunted/eutrophic), diagnosed by means of the height deficit (height-for-age < -2,0 SD). Each group was divided in two sub-groups agreements the insufficient birth weight (IBW < 3000g). Finally, each sub-group formed two other categories according to the exposition or not to the exclusive breastfeeding in the first month of life (breastfeeding/ not breastfeeding). Thus, eight groups of studies were formed, which, for the statistics analysis, had been expresses as ordinary category variables (1 a 8), group 1 was formed for the children submitted to worst conditions (undernutrition, with IBW and that weren t to breastfed) and group 8 for the best ones (eutrophic with adequate birth weight and that was to breastfed). The average of the head circumferencefor- age (HC) was compared using ANOVA and the Turkey test as pos-hoc. For this, group 8 was assumed as control. To investigate the principal risk factors associated to the occurrence of the deficit of HC (z < 1.5), regression logistic analyze was used, remaining in the last model the independent variables which associations presented p<0.05. Results: The prevalence of nutritional deficits for indicators height-for-age, weight-forage, weight-for-height and head circumference-for-age was respectively of 10.8%, 1.9%, 1.3% e 10.5%. The overweight (weigh-for-age > 2 SD) represents 6.4%. The averages of Z-score of the head circumference for the groups 1, 2, 3, 4, 5, 6, 7 e 8 was -1.67*, -1.09, - 0.97, -0.94, -1.02, -0.69, -0.68 e -0.53 respectively. Group 1 was the unique that presented statistics differences (p< 0,05) compared to the control group, suggesting the protective role of breasting against reduction of the HC, when the presence of the chronic malnutrition (express for height deficit) in children that were born with IBW, because the exposition to exclusive breastfeeding was the unique differential used on the formation of the groups 1 and 2. On the multivaried analyzis, the factors that were significantly associated to deficit of HC were the stunted, the insufficient birth weight, the feminine sex and the increase of chronological age in one month increase the chances of occurrence these outcomes in 119%, 77%, 63% e 2% respectively. But the increase of time of the exclusive breastfeeding in one month reduces the possibilities in 10%. Conclusions: The children who are stunted, are born with insufficient weight and that they had not been was exposed to exclusive breastfeeding for one month, demonstrate consistently the worst averages of Z-score of head circumference when compared to children not submitted to stress . In this context, the exposition of breastfeeding per for one month possibly, of the central nervous system. Although traditional population have been considered, the average time of the exclusive breastfeeding was behind of the praised for the WHO. Thus, it was suggested the more investments on the direction of the increase the period of the exposition to exclusive breastfeeding between the quilombolas children of the Alagoas state. / Objetivo: Investigar se o perímetro cefálico de crianças quilombolas com déficit estatural difere daquela observado em crianças com crescimento linear adequado e se o peso insuficiente ao nascer e o aleitamento materno exclusivo no primeiro mês de vida interfere nessa relação. Métodos: Estudo transversal envolvendo todas as crianças de 12 a 60 meses (n=725) pertencentes às comunidades quilombolas (n=39) de Alagoas. Coletaram-se dados demográficos, socioeconômicos, de saúde e antropométricos. Estes foram comparados às curvas do padrão de referência da OMS-2006. As crianças foram categorizadas em 2 grupos conforme a presença ou não da desnutrição (desnutrida/eutrófica), diagnosticada por meio do déficit estatural (estatura-para-idade < - 2,0 desvio-padrão). Cada grupo foi subdivido em 2 sub-grupos conforme o Peso Insuficiente ao Nascer (PIN < 3000g). Finalmente, cada sub-grupo formou duas outras categorias segundo a exposição ou não ao aleitamento materno exclusivo por 30 ou mais dias (mamou/não mamou). Assim, formaram-se oito grupos de estudos, os quais, para a análise estatística, foram expressos como variáveis categóricas ordinais (1 a 8), de modo que o grupo 1 fora formado pelas crianças submetidas às piores condições (desnutridas, com PIN e que não mamaram) e o grupo 8 pelas melhores (eutróficas, com peso adequado ao nascer e que mamaram). A média do perímetro cefálico-para-idade (PC) foi comparada utilizando ANOVA e o teste de Tukey como pos-hoc. Para isso, assumiu-se o grupo 8 como controle. Para investigar os principais fatores de risco associados à ocorrência do déficit de PC (z < -1,5), utilizou-se a análise de regressão logística, mantendo-se no modelo final as variáveis independentes cujas associações apresentaram p<0,05. Resultados: As prevalências de déficits nutricionais para os índices altura-para-idade, peso-para-idade, peso-para-altura e PC foram, respectivamente, 10,8%, 1,9%, 1,3% e 10,5%. O sobrepeso (peso-para-altura > 2 DP) representou 6,4%. As médias de escore Z do perímetro cefálico para os grupos 1, 2, 3, 4, 5, 6, 7 e 8 foram -1,67*, -1,09, -0,97, -0,94, - 1,02, -0,69, -0,68 e -0,53, respectivamente. O grupo 1 foi o único que apresentou diferença estatisticamente significativa (p < 0,05) em relação ao grupo controle, sugerindo um papel protetor do aleitamento materno contra a redução do PC, quando da vigência da desnutrição crônica (expressa pelo déficit estatural) em crianças nascidas com PIN, haja vista que a exposição ao aleitamento materno foi o único diferencial utilizado na formação dos grupos 1 e 2. Na análise multivariada, os fatores que se apresentaram significativamente associados ao déficit de PC foram o déficit estatural, o PIN, o sexo feminino e o aumento da idade cronológica em um 1 mês, as quais, elevaram as chances de ocorrência desse desfecho em, respectivamente, 119%, 77%, 63% e 2%. O aumento do tempo de aleitamento materno exclusivo em um mês, reduziram essas chances em 10%. Conclusões: As crianças que apresentam baixa estatura, nascem com peso insuficiente e que não foram expostas ao aleitamento materno exclusivo por pelo menos 1 mês apresentam menores valores de perímetro cefálico, quando comparadas a crianças não submetidas a esses estresses. Nesse contexto, a exposição ao aleitamento materno exclusivo por 30 ou mais dias constitui-se num importante fator de proteção, no sentido de preservar o crescimento do perímetro cefálico e possivelmente, do sistema nervoso central. Apesar de tratar-se de uma população dita tradicional, o tempo médio de aleitamento materno exclusivo ficou aquém do preconizado pela OMS. Diante desses resultados, sugere-se maiores investimentos no sentido de aumentar entre as crianças quilombolas de Alagoas, o período de exposição ao aleitamento materno exclusivo.
20

Too Long and Too Boring: The Effects of Survey Length and Interest on Careless Responding

Brower, Cheyna Katherine 01 June 2018 (has links)
No description available.

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