92 research outputs found
효율적인 광 증감 제로 비 풀러렌 기반 2D 평면형 소분자 반도체를 사용하여 초박형 광증 배 포토 다이오드 제작
No full textPhoto Multiplication, Photodetector, Organic Photodiode,High Detectivity, Optical SensitizerIn this work, we explore the possibility of using nonfullerene and a planar n-type small molecular semiconductor, 2,2′‐((2Z,2′Z)‐((4,4,9,9‐tetrahexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐2,7‐diyl)bis(methanylylidene))bis(3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile (IDIC) as an optical sensitizer to improve the EQE and to reduce the thickness of the photoactive layer to 70 nm. A key idea of this work is utilizing the unique photophysical properties of IDIC with an anisotropic electron transport. As is well known, contrary to spherical PCBMs (PC61BM and PC71BM) with an isotropic charge transport property, the 2D planar IDIC with an inherently anisotropic packing structure tends to hinder the formation of the effective electron percolation pathways. This is a very important requirement for the optical sensitizer of PM-OPDs because it leads to more efficient charge trapping. In addition, IDIC possesses a relatively higher absorption coefficient in the visible range compared to PC71BM, which can contribute to a higher photocurrent. Together with a deeper lowest unoccupied molecular orbital (LUMO) level of IDIC compared to PC71BM, all the mentioned photophysical properties of IDIC can be much more beneficial as optical sensitizers of the PM-OPDs. Layer-by-layer deposition of P3HT as a photoactive layer and IDIC as an optical sensitizer enables more effective PM operation, yielding high EQE exceeding 130,000% and specific detectivity over 1012 Jones at 150-nm-thick active layer. Furthermore, due to more facile spatial confinement of the charge carriers, the photoactive layer thickness was further decreased down to 70 nm while maintaining reasonably high EQE of 60,000% as well as specific detectivity over 1012 Jones. Physical origins of such synergetic effects of using IDIC as an optical sensitizer are fully discussed with various photophysical analyses in the forthcoming sections.open1 - Introduction 2
1.1 Introduction to PM based Photodetector 2
1.2 Mechanism – Photo Multiplication Type Photodetector 3
1.3 PM Type Photodetector – Advantages and Disadvantages 4
1.4 Recent Trends in PM type Photodiodes 5
1.5 Current Theses Work 7
2 – Experimental Section 9
2.1 Preparations 9
2.1.1 Material Preparations 9
2.1.2 Device Preparations 10
2.2 Characterizations 11
2.2.1 Material Characterization 11
2.2.2 Device Characterization 14
3 – Results and Discussions 17
4 – Conclusions 31본 연구에서는 100 nm 이하의 얇은 광활성층 두께 조건에서 높은 외부 양자 효율을 구현하기 위해, 평면 분자 구조를 가지는 비 풀러렌 전자 받개인 2,2′‐((2Z,2′Z)‐((4,4,9,9‐tetrahexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐2,7‐diyl)bis(methanylylidene))bis(3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile (IDIC)의 광학적 감응제(optical sensitizer)로서의 활용 가능성을 타진하였다. 본 연구는 핵심은 기존의 구형 구조를 가지는 풀러렌 계열 전자 받개(PC61BM, PC71BM)에서 보이는 등방적인 전자 전달과는 반대인 IDIC의 비등방적인 전자 전달을 활용하는 것으로, 이러한 비등방적인 패킹 구조는 전자의 효율적인 여과 경로(percolation pathway)의 형성을 저해하게 된다. 따라서 이러한 현상은 전하의 트랩에 있어 굉장히 용이하다고 할 수 있는데, 때문에 광 증폭(photomultiplication) 메커니즘 기반의 유기 포토디텍터(organic photodetector, OPD) 구조에서 광학적 감응제로 적용하기에 적합하다고 할 수 있다. 또한, IDIC는 기존의 풀러렌 계열 전자 받개들에 비해 가시광선 영역의 파장에 대해 더 높은 흡광 계수를 가지는데, 이는 흡광 효율의 향상을 야기하여, 결과적으로 기존에 비해 더 높은 광전류를 구현할 수 있게 한다. 상기 서술한 광물리적인 특성과 더불어, IDIC는 풀러렌 계열 전자 받개에 비해 더 낮은 최저 빈 분자 궤도(lowest unoccupied molecular orbital, LUMO) 준위를 가지는데, 이러한 특성 또한 PM-OPD 구조에서 광학적 감응제로서 풀러렌 계열 전자 받개에 비해 더욱 낫다고 할 수 있다. 소자 구현을 위해, 광활성층으로 IDIC와 함께 poly(3-hexylthiophene-2,5-diyl) (P3HT)을 사용하였고, 소자 성능의 비교를 위해 IDIC 대신 PC71BM을 적용한 소자 또한 제작하였다. 더 효율적인 광 증폭 메커니즘 구현을 위해, P3HT와 IDIC 또는 PC71BM을 층층이 배치(layer-by-layer deposition)하였고, 이를 통해 약 150 nm의 매우 얇은 광활성층을 이용하여 130,000% 이상의 외부 양자 효율과 1012 Jones 이상의 검출능을 가지는 고성능 유기 포토디텍터를 구현할 수 있었다. 또한, 기존 풀러렌 계열 전자 받개를 사용한 경우에 비해 IDIC를 사용할 때 더 강한 전하의 공간적 구속(spatial confinement)이 이루어짐을 확인하여 광활성층의 두께를 더욱 낮추었고, 약 70 nm 정도의 매우 얇은 광활성층 조건에서도 60,000% 이상의 매우 높은 외부 양자 효율을 보임을 확인하였다.MasterdCollectio
Liposomal nucleation and triglyceride extraction from pomegranate seeds using supercritical carbon dioxide
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Semi-supervised Aspect Based Sentiment Analysis for Movies Using Review Filtering
No full textAbstractAspect based Sentiment Analysis (ABSA) is a subarea of opinion mining which enables one to gain deeper insights into the features of items which interest the users by mining reviews. In this paper we attempt to perform ABSA on movie review data. Unlike other domains such as camera, laptops restaurants etc, a major chunk of movie reviews is devoted to describing the plot and contains no information about user interests. The presence of such narrative content may potentially mislead the review analysis. The contribution of this paper is two-fold: a two class classification scheme for plots and reviews without the need for labeled data is proposed. The overhead of constructing manually labeled data to build the classifier is avoided and the resulting classifier is shown to be effective using a small manually built test set. Secondly we propose a scheme to detect aspects and the corresponding opinions using a set of hand crafted rules and aspect clue words. Three schemes for selection of aspect clue words are explored - manual labeling (M), clustering(C) and review guided clustering (RC). The aspect and sentiment detection using all the three schemes is empirically evaluated against a manually constructed test set. The experiments establish the effectiveness of manual labeling over cluster based approaches but among the cluster based approaches, the ones utilizing the review guided clue words performed better
Generalizations and Interpretations of Incipient Infinite Cluster measure on Planar Lattices and Slabs
Full text linkThis thesis generalizes and interprets Kesten\''s Incipient Infinite Cluster (IIC) measure in two ways. Firstly we generalize Járai\''s result which states that for planar lattices the local configurations around a typical point taken from crossing collection is described by IIC measure. We prove in Chapter 2 that for backbone, lowest crossing and set of pivotals, the same hold true with multiple armed IIC measures. We develop certain tools, namely Russo Seymour Welsh theorem and a strong variant of quasi-multiplicativity for critical percolation on 2-dimensional slabs in Chapters 3 and 4 respectively. This enables us to first show existence of IIC in Kesten\''s sense on slabs in Chapter 4 and prove that this measure can be interpreted as the local picture around a point of crossing collection in Chapter 5
Hirsch-Sprung’s Disease – A Panchkarma Approach for the Congenital Malformation of Colon
No full textHirschsprung’s disease is a congenital disorder of large intestine in which certain ganglionic cells are absent in a particular segment of colon resulting in absence of peristalsis. The lack of movement of intestine and the failure of relaxation of internal anal sphincter produces varying degree of intestinal obstruction, which results in symptoms like- constipation, abdominal distension, nausea and loss of appetite etc. In allopathic medical science the treatment is surgical removal of the affected area followed by anastomosis. In present case study an Ayurvedic approach was considered by analyzing the factors involved at the level of dosha-dushya and srotas for the disease. And the line of treatment was planned as deepan-pachan, snehan, swedan, mridu samshodhan with basti, mridu virechaka aushadhies, vata-anuloman and pathya ahara-vihara. By following this, encouraging results were obtained in this case with regular bowel pattern and relief in other symptom
Clinical Study of Upper Gastrointestinal Endoscopy in Patients Presenting with Dysphagia in a Tertiary Care Hospital
Full text linkINTRODUCTION :
The Greek word “Dysphagia” means disordered eating. It is the subjective sensation of difficulty in swallowing .Upper gastro intestinal endoscopy is the most common initial diagnostic procedure performed in the evaluation of oesophageal dysphagia as there is direct visualisation of the entire upper Gastrointestinal tract.
AIMS & OBJECTIVES :
A clinical study of upper gastrointestinal endoscopy in patients presenting with dysphagia, the following are the aims & objective of the study
1. To evaluate the diagnostic potential of endoscopy in patients with dysphagia.
2. To analyse the nature and frequency of various upper gastrointestinal conditions both in benign & malignant conditions.
3. Incidence of malignancy among the patients with dysphagia
4. To study the etiological factors and its association with dysphagia .
MATERIAL AND METHODOLOGY :
94 Patients who were presenting with symptom of dysphagia from the period of Aug-2014 to Aug-2016 in the department of general surgery were included in the study. The patients who presented with complaints of dysphagia to the outpatient department
and patients admitted with complaint of dysphagia were evaluated with upper gastro intestinal endoscopy.
RESULTS AND CONCLUSION :
The study was conducted among 94 patients.Out of which 46cases were diagnosed to have malignant causes ,36 were of benign etiology,12 of them with normal findings. The dysphagia incidence between the adult male and elderly male subjects were 43.2% and 56.7% with higher incidence in elderly males.
In this study the incidence of the males were significantly greater than females.
The mean age of sedentary and moderate subjects was not significantly differed. The sedentary subjects mean age was lesser than the heavy occupational subjects.
The incidence of dysphagia was very strongly associated with male heavy workers and sedentary female workers.
The smokers were significantly more affected than the non smokers The solid dysphagia was significantly more than the solid + liquid dysphagia. The non weight loss was significantly greater than the weight loss.. The major finding of the OGD was carcinoma and related symptoms. Next to carcinoma oesophagus was gastro oesophageal junction growth. Next to gastro oesophageal junction growth was LAX lower oesophageal Spinchter
DExT: Detector Explanation Toolkit for Explaining Multiple Detections Using Saliency Methods
No full textAs cameras are ubiquitous in autonomous systems, object detection is a crucial task. Object detectors are widely used in applications such as autonomous driving, healthcare, and robotics. Given an image, an object detector outputs both the bounding box coordinates as well as classification probabilities for each object detected. The state-of-the-art detectors are treated as black boxes due to their highly non-linear internal computations. Even with unprecedented advancements in detector performance, the inability to explain how their outputs are generated limits their use in safety-critical applications in particular. It is therefore crucial to explain the reason behind each detector decision in order to gain user trust, enhance detector performance, and analyze their failure.
Previous work fails to explain as well as evaluate both bounding box and classification decisions individually for various detectors. Moreover, no tools explain each detector decision, evaluate the explanations, and also identify the reasons for detector failures. This restricts the flexibility to analyze detectors. The main contribution presented here is an open-source Detector Explanation Toolkit (DExT). It is used to explain the detector decisions, evaluate the explanations, and analyze detector errors. The detector decisions are explained visually by highlighting the image pixels that most influence a particular decision. The toolkit implements the proposed approach to generate a holistic explanation for all detector decisions using certain gradient-based explanation methods. To the author’s knowledge, this is the first work to conduct extensive qualitative and novel quantitative evaluations of different explanation methods across various detectors. The qualitative evaluation incorporates a visual analysis of the explanations carried out by the author as well as a human-centric evaluation. The human-centric evaluation includes a user study to understand user trust in the explanations generated across various explanation methods for different detectors. Four multi-object visualization methods are provided to merge the explanations of multiple objects detected in an image as well as the corresponding detector outputs in a single image. Finally, DExT implements the procedure to analyze detector failures using the formulated approach.
The visual analysis illustrates that the ability to explain a model is more dependent on the model itself than the actual ability of the explanation method. In addition, the explanations are affected by the object explained, the decision explained, detector architecture, training data labels, and model parameters. The results of the quantitative evaluation show that the Single Shot MultiBox Detector (SSD) is more faithfully explained compared to other detectors regardless of the explanation methods. In addition, a single explanation method cannot generate more faithful explanations than other methods for both the bounding box and the classification decision across different detectors. Both the quantitative and human-centric evaluations identify that SmoothGrad with Guided Backpropagation (GBP) provides more trustworthy explanations among selected methods across all detectors. Finally, a convex polygon-based multi-object visualization method provides more human-understandable visualization than other methods.
The author expects that DExT will motivate practitioners to evaluate object detectors from the interpretability perspective by explaining both bounding box and classification decisions
Toxic gases detection and tolerance level classification using machine learning algorithms
Full text linkAbstract— with rapid population increases, people are facing the challenge to maintain healthy conditions. One of the challenges is air pollution. Due to industrial development and vehicle usage air pollution is becoming a high threat to human life. This air pollution forms through various toxic contaminants. This toxic contamination levels increase and cause severe damage to the living things in the environment. To identify the toxic level present in the polluted air various methods were proposed by the authors, But failed to detect the tolerance level of toxic gases. This article discusses the methods to detect toxic gasses and classify the tolerance level of gasses present in polluted air. Various sensors and different algorithms are used for classifying the tolerance level. For this purpose “Artificial Sensing Methodology” (ASM), commonly known as e-nose, is a technique for detecting harmful gases. SO2-D4, NO2-D4, MQ-135, MQ136, MQ-7, and other sensors are used in artificial sensing methods (e-nose). “Carbon monoxide, Sulfur dioxide, nitrogen dioxide, and carbon dioxide” are all detected by these sensors. The data collected by sensors is sent to the data register from there it is sent to the Machine learning Training module (ML) and the comparison is done with real-time data and trained data. If the values increase beyond the tolerance level the system will give the alarm and release the oxygen
Typologies of anger in a clinical sample with mild cognitive impairment
No full textThis item is available only to currently enrolled UTSA students, faculty or staff. To download, navigate to Log In in the top right-hand corner of this screen, then select Log in with my UTSA ID.Individuals diagnosed with Mild Cognitive Impairment (MCI) report a gradual decline in memory, intelligence, and/or executive functioning which leads to mild-to-moderate deficits in Instrumental Activities of Daily Living: complex activities required for independent living, such as paying bills, remembering appointments, and maintaining a home (Petersen et al., 2001; Cahn-Weiner et al., 2007; West, McCue, & Golden, 2012). Along with these symptoms, patients with MCI often report increased levels of negative affect; specifically, depression, anxiety, and anger (Banningh, Vernooij-Dassen, Rikkert, & Teunisse, 2008). This paper sought to acquire quantitative, normative data on anger experience and expression in this target population. Additionally, this study regressed anger onto neuropsychological and sociodemographic variables to examine their role as potential predictors of anger experience and expression. Furthermore, to demonstrate anger's position in the triad of negative affect alongside depression and anxiety, regression analysis was employed. Normative anger data indicated 50% of MCI patients experienced sub-clinical or clinical levels of anger, but the majority expressed this anger in socially acceptable manners. Moreover, a negative linear trend was observed between age and anger experience, indicating people experience less anger as they age. Lastly, anger was positively associated with both depression and anxiety, highlighting its role as a core member in negative affect.Psycholog
A Study of Post-Mortem Artefacts in Deaths Autopsied at Government Kilpauk Medical College Chennai
Full text linkAIM OF THE STUDY:
1. To study the prevalence of post-mortem artefacts.
2. To profile the various factors contributing to the post-mortem artefacts.
3. To suggest preventive measures to minimize post-mortem artefacts.
OBJECTIVES OF THE STUDY:
1. To differentiate an ante-mortem injury from a post-mortem artifact.
2. To indentify the most common post-mortem artifact.
3. To enumerate the various factors leading to the post-mortem artefacts.
4. To identify the most common reason for artifact formation.
5. To recognize what are the precautions to be taken to minimize artefacts.
METHODOLOGY:
The present work is a cross-sectional study of artefacts in all the autopsies conducted in the Department of Forensic Medicine & Toxicology, Govt. Kilpauk Medical College & Hospital between January 2017 and December 2017.
RESULTS:
During this study period, out of 2866 cases that came for autopsy, 358 cases were selected by simple randomization and were studied. Out of the 358 cases, presence of artefacts was confirmed in 122 cases which accounted for 34%. Maximum number of artefacts was noted among male sex in 41-50 years age group, in the south-west monsoon season, more commonly in the month of June.
Artefacts are more frequently seen in the sudden deaths, those deaths occurring in the evening time period, those having a wide post-mortem interval of more than 36 hours and in those bodies retrieved on the roadside.
Unknown dead bodies, hospital treated deaths and decomposed bodies are more susceptible for artefact formation.
Among the 122 cases positive for artefacts, artefacts were introduced before autopsy in 102 cases (83.7%), while in 20 cases it was introduced during autopsy (16.3%). Among the 102 artefacts identified as introduced between death and autopsy, 7 were identified as agonal artefacts (6.9%), 32 were due to post-mortem changes(31.4%), 44 were third party artefacts (43.1%), while 5 were due to environmental causes (4.9%) and 14 cases accounted for miscellaneous artefacts (13.7%). Maggots activity were the most common artefact accounting for 12 cases (11.7%) followed by ant bite marks which were seen in 11 cases (10.7%). The artefacts due to decomposition changes were the second most common artefact of which, the oozing of Post-Mortem fluid is the major decomposition artefact.
Toxicological artefacts like contamination of blood with pericardial fluid, gastric contents while collecting and mixing with wrong preservative were noted in 3 cases that contributed for 15.0% of the artefacts introduced during autopsy
- …
