State-of-the-art InAs/GaAs quantum dot material for optical telecommunication

This thesis reports on the characterization of the state-of-the-art In(Ga)As/GaAs quantum dot (QD) material grown by molecular beam epitaxy for optical telecommunication applications. A wide variety of characterization methods are employed to investigate the material properties and characteristics of a number of QD-based devices enabling future device optimization. The motivation that prompted this study was predicated mainly upon two technological advantages. First, that the QDs gain spectra exhibits a symmetric gain shape and thus the change of refractive index with respect to gain is negligible at the lasing wavelength. This is therefore expected to result in a zero or a very small linewidth enhancement factor (LEF), which is desirable for instance, for high-speed modulation purposes where frequency chirp under modulation, which is directly proportional to the LEF, may be substantially reduced. Second, the fact that not only QDs exhibit a damped frequency response attributed to the carrier relaxation dynamics but also as the resilience of a laser to optical feedback is inversely proportional to the fourth power of the LEF, QD lasers are expected to demonstrate a relatively higher feedback insensitivity. This bodes well for operating these devices isolator free, which would be greatly cost-effective. The absorption and gain spectra of the QD active material are investigated in chapters 2 and 3, respectively. The LEF of QD lasers at a range of temperatures is studied in chapter 3, which confirms the expectation for the first time for In(Ga)As/GaAs QD lasers from -10 oC to 85 oC. Subsequently, the findings of chapters 2 and 3 are employed in chapter 4 with an electro absorption modulator device in mind which would be able to operate with chirp control. In chapter 5, the modulation response of QD lasers is investigated through examining the relative intensity noise (RIN) spectra in the electrical domain. The resilience of the devices to optical feedback is subsequently studied through the RIN characteristics at a range of temperatures. Chapter 6 provides a summary of the thesis findings and possible future works that may be carried out as continuation to this project, which fell outside of the remit of this work

Intra Corneal Cleft Secondary to Ocular Massage after Ahmed Valve Surgery

Purpose: To report a case of acute intra corneal cleft in a patient undergoing ocular massage following Ahmed valve implantation. Case Report: Acute intra corneal cleft occurred in a patient following the use of ocular massage to reduce IOP and bleb formation after Ahmed glaucoma valve insertion. Previous history of the patient was Fuchs heterochromic iridocyclitis without any report of trauma to his eye or any other ophthalmic disorders. The slit lamp examination revealed huge localized corneal bulla formation with a diameter of 3 mm in the superior mid peripheral corneal region in the right eye just after ocular massage, which persisted in the 6 months of follow up. Conclusion: Digital ocular massage might cause the occurrence of intra corneal cleft. Although this might be a very rare complication, we should consider it as an adverse effect of ocular massage.Keywords: Glaucoma; Cornea; Cleft; Massage

Novel silver-doped NiTiO3: auto-combustion synthesis, characterization and photovoltaic measurements

Novel silver-doped nickel titanate nanoparticles (Ag-NiTiO3) were successfully prepared via a sol-gel method in the presence of stearyl alcohol as the capping agent and solvent. The formation of pure crystallized nickel titanate and silver-doped nickel titanate was occurred when the precursor was heat-treated at 700 °C in air for 150 and 60 min, respectively. The structural, morphological, and optical properties of obtained products were characterized by techniques such as X-ray diffraction (XRD), Fourier transforminfrared (FT-IR) spectroscopy, Energy dispersive X-ray microanalysis (EDX), ultraviolet-visible (UV-vis), and scanning electron microscopy (SEM). The magnetic property of the prepared Ag-NiTiO3 nanoparticles was also investigated with vibrating sample magnetometer (VSM). To fabricate a FTO/TiO2/Ag-NiTiO3/Pt-FTO solar cell, Ag-NiTiO3 film was directly deposited on top of the TiO2 prepared by electrophoresis deposition method. Furthermore, solar cell result indicates that an inexpensive solar cell could be developed by the synthesized Ag-NiTiO3 nanoparticles.Keywords: Ag-NiTiO3, sol-gel method, semiconductor, photovoltaic, dopin

DeePLT: Personalized Lighting Facilitates by Trajectory Prediction of Recognized Residents in the Smart Home

In recent years, the intelligence of various parts of the home has become one of the essential features of any modern home. One of these parts is the intelligence lighting system that personalizes the light for each person. This paper proposes an intelligent system based on machine learning that personalizes lighting in the instant future location of a recognized user, inferred by trajectory prediction. Our proposed system consists of the following modules: (I) human detection to detect and localize the person in each given video frame, (II) face recognition to identify the detected person, (III) human tracking to track the person in the sequence of video frames and (IV) trajectory prediction to forecast the future location of the user in the environment using Inverse Reinforcement Learning. The proposed method provides a unique profile for each person, including specifications, face images, and custom lighting settings. This profile is used in the lighting adjustment process. Unlike other methods that consider constant lighting for every person, our system can apply each 'person's desired lighting in terms of color and light intensity without direct user intervention. Therefore, the lighting is adjusted with higher speed and better efficiency. In addition, the predicted trajectory path makes the proposed system apply the desired lighting, creating more pleasant and comfortable conditions for the home residents. In the experimental results, the system applied the desired lighting in an average time of 1.4 seconds from the moment of entry, as well as a performance of 22.1mAp in human detection, 95.12% accuracy in face recognition, 93.3% MDP in human tracking, and 10.80 MinADE20, 18.55 MinFDE20, 15.8 MinADE5 and 30.50 MinFDE5 in trajectory prediction

Investigando o nível do estranho (Shathi) nos ensinamentos de Bahá'u'lvalad

The wordless of the mystical experience makes the mystics and Sufis, through the use of secrets and parables, to express non-existent facts beyond the wisdom, mystics believe that the form (appearance) can not show secrets and meanings of mystic. In this regard, Sultan El- Olama Baha'ulvalad, like other mystics, wants to express his mystical experiences to others, but the interpretation and description of these experiences can not be expressed in ordinary language, but the mystic does not have a tool other than language to refer to these mystical states, or must be secrets and mysteries or must say by language, in this way raises the temptation to express or not the mystical secrets by odd mysticism .Baha'ulvalad presents his mystical experiences according to the rules of the language, and this expressiveness leads to the creation of a odds (Shatifi) in his mystical language.Los sin palabras de la experiencia mística hacen que los místicos y sufíes, a través del uso de secretos y parábolas, expresen hechos inexistentes más allá de la sabiduría, los místicos creen que la forma (apariencia) no puede mostrar secretos y significados de místicos. En este sentido, el sultán El-Olama Bahá'ulvalad, como otros místicos, quiere expresar sus experiencias místicas a otros, pero la interpretación y descripción de estas experiencias no puede expresarse en un lenguaje común, pero el místico no tiene otra herramienta. que el lenguaje para referirse a estos estados místicos, o debe ser secretos y misterios o debe decirse por el lenguaje, de esta manera aumenta la tentación de expresar o no los secretos místicos por extraño misticismo. Baha'ulvalad presenta sus experiencias místicas de acuerdo con las reglas del lenguaje, y esta expresividad conduce a la creación de una probabilidad (Shatifi) en su lenguaje místico.O sem palavras da experiência mística faz com que os místicos e sufis, através do uso de segredos e parábolas, expressem fatos inexistentes além da sabedoria, místicos acreditam que a forma (aparência) não pode mostrar segredos e significados do místico. A este respeito, o sultão El-Olama Baha'ulvalad, como outros místicos, quer expressar suas experiências místicas a outros, mas a interpretação e a descrição dessas experiências não podem ser expressas em linguagem comum, mas o místico não tem outra ferramenta do que a linguagem para se referir a esses estados místicos, ou deve ser segredos e mistérios, ou deve dizer, pela linguagem, dessa forma, suscita a tentação de expressar ou não os segredos místicos pelo misticismo estranho. Baha'ulvalad apresenta suas experiências místicas de acordo com as regras da linguagem, e essa expressividade leva à criação de uma probabilidade (Shatifi) em sua linguagem mística.&nbsp

A sustainability approach to vehicle modular platform design: A mathematical model

Today, sustainability and its economic, social, and environmental pillars are the main elements of new product market development. Therefore, manufacturers, considering all stages of a product life-cycle, consider it necessary to have a framework for producing sustainable products. Moreover, new product design and development processes especially sub-process of product definition and detailed design processes can play a very critical role in developing product sustainability. This paper considers the role that the car platform can play in creating a family of products and with regard to various data related to the environmental, economic, and social pillars of each of the 15 modules of a car platform and also, using the best–worst method technique and multi-objective mathematical programming with the augmented epsilon constraint method, we were able to achieve a set of platforms with maximum sustainability. The present study explores the possibility of determining the most efficient combinations of modules for every one of the 23 cars’ platforms to produce a collection of products. Through these methods, the 54 efficient solutions in the Pareto front were achieved, and out of this number, after considering all the factors and weights of the objective functions, solution no. 51 was selected as the most efficient. Subsequently, all the 15 module variants of the 23 platforms were determined for solution no. 51. Finally, these variants were ranked on the basis of the SAW technique, and finally, sensitivity analysis is done

Anterior Uveitis after Subconjunctival Injection of Mitomycin C in a Patient with Previous Trabeculectomy

Objective: To report a case of anterior uveitis after subconjunctival mitomycin C injection in a patient with a history of trabeculectomy. Case Report: A 45 year old patient, with anterior uveitis in his right eye after postoperative injection of mitomycin C one month after trabeculectomy, was treated in Basir eye clinic, Tehran, Iran. The Patient had no history of previous ocular infection. Topical prednisolone and tropicamide drops were effective in improving vision and reducing pain in our case.Conclusion: Anterior uveitis might happen after trabeculectomy surgery; however, in our case, it was more likely the result of mitomycin C administration one month after trabeculectomy. This should be considered as a differential diagnosis of postoperative bleb infections. Keywords: Uveitis; Mitomycin C; Trabeculectomy

Association of Meibomian Gland Dysfunction Severity and Glycohemoglobin Levels in Type 2 Diabetic Patients

Purpose: To investigate the association of meibomian gland dysfunction severity and glycated hemoglobin A (HbA1c) levels among type 2 diabetic patients. Patients and Methods: In this cross-sectional, 40 type 2 diabetic patients with meibomian gland dysfunction (MGD) were studied at Basir Eye Clinic, Tehran, Iran. An expert ophthalmologist determined the MGD stage based on staging scale outlined in American academy of ophthalmology's basic and clinical science course. The HbA1c level was measured applying a standard method, certified by the National Glycohemoglobin Standardization Program (NGSP). We divided patients to two groups based on their HbA1C level; the first group included patients with HbA1c < 6.5 % and the second group included patients with HbA1c ≥ 6.5  %.Results: Our results demonstrated that 12.5 % of the participants had minimal, 52.5 % had mild and 35 % had moderate to severe MGD. We observed that different levels of HbA1c (over or under 6.5 %) were significantly associated with MGD severity (P < 0. 013). Moderate to severe MGD stage was observed in 43.7 % of individuals with HbA1c ≥ 6.5 %, while it was found in none of participants with HbA1c < 6.5 %. With increase in HbA1c level, the risk of moderate to severe MGD occurrence increased (OR = 3.57; 95 % CI: 1.05-12.13; P = 0.041). This association was not confounded by age or gender.   Conclusion: Meibomian gland dysfunction severity has an association with HbA1c levels in diabetic type 2 patients, and a rise in HbA1c noticeably aggravates the MGD stage.Keywords: Glycated hemoglobin A; Meibomian gland dysfunction; Diabetes mellitus; Dry eye syndromes; Diabetes

Comparison of Lumbopelvic and Hip Movement Patterns During Passive Hip External Rotation in Two Groups of Low Back Pain Patients with and without Rotational Demand Activities.

BACKGROUND Because different groups of people with low back pain (LBP) engage in different tasks, their lumbopelvic-hip complex may move in different ways in those groups. The purpose of this study was to quantify the differences in lumbopelvic movement pattern during the passive hip external rotation (PHER) test in LBP patients with and without rotational demand activities (RDA). MATERIAL AND METHODS A total of 30 subjects with LBP, including 15 patients with-RDA and 15 patients without-RDA were enrolled. A passive hip external rotation test was performed. Pelvic and hip rotation over the full range of the test, timing of hip and pelvic motion, and pelvic rotation in the first half of the movement were measured using a 3-D motion analysis system. RESULTS Passive pelvic rotation during the test in the group with RDA was significantly greater than in the other group. However, there was no significant difference between the groups in other kinematic variables, including hip external rotation, timing of hip and pelvic motion and pelvic rotation in the first half of the movement (p > 0.05). CONCLUSIONS 1. A greater lumbopelvic rotation ROM during the PHER existed in LBP patients who regularly participated in RDA. 2. Different groups of patients with LBP who engage in different specific activities may have a specific lumbopelvic movement pattern impairment. Therefore, each group of LBP patients in regard to their specific activities may need a different, specific plan of treatment