Model-based vs. model-free visual servoing: A Performance evaluation in microsystems

In this paper, model-based and model-free image based visual servoing (VS) approaches are implemented on a microassembly workstation, and their regulation and tracking performances are evaluated. A precise image based VS relies on computation of the image jacobian. In the model-based visual servoing, the image Jacobian is computed via calibrating the optical system. Precisely calibrated model based VS promises better positioning and tracking performance than the model-free approach. However, in the model-free approach, optical system calibration is not required due to the dynamic Jacobian estimation, thus it has the advantage of adapting to the different operating modes

Novel parameter estimation schemes in microsystems

This paper presents two novel estimation methods that are designed to enhance our ability of observing, positioning, and physically transforming the objects and/or biological structures in micromanipulation tasks. In order to effectively monitor and position the microobjects, an online calibration method with submicron precision via a recursive least square solution is presented. To provide the adequate information to manipulate the biological structures without damaging the cell or tissue during an injection, a nonlinear spring-mass-damper model is introduced and mechanical properties of a zebrafish embryo are obtained. These two methods are validated on a microassembly workstation and the results are evaluated quantitatively

Variability of Different Pear Hybrid Populations in Terms of Hybridization Performance and the Response to Fire Blight (Erwinia amylovora) Attack

The production of pear, which is one of the most important fruits in Turkey, was restricted by the occurrence of the fire blight disease. There isn’t a certain chemical management against fire blight, although plant activators have been used, at present. It’s very important to improve resistant varieties in terms of an integrated management of bacterial diseases. With this purpose, different crosses have been made between resistant cultigens and P. communis varieties that have good fruit characteristics. Besides, self-pollination and open pollination treatments have been carried out in parental plants. Pollen viability and germination ratio, fruit set ratio, total and mean seed number, seed germination ratio, the ratio of hybrid losses by root rot at early stage and the ratio of hybrid losses by natural fire blight infection were determined. The highest values of the properties such as pollen viability and germination ratio, fruit set ratio, mean and total seed number were obtained from the crosses with ‘Kaiser Alexandre’, ‘Ankara’, ‘Akça’, ‘Conference’ and ‘Santa Maria’ cultivars, in general. As a result of natural fire blight infection in Izmir-Turkey conditions, the resistance level of the hybrids from various combinations differed through the cultivars used for cross pollination, and it is very important to evaluate these hybrid pear populations through their response to fireblight disease in terms of obtaining new resistant cultivars and using these populations as disease resistant genetic resources in the future

LYS Başarılarına Göre Okul Performanslarının Eğitsel Veri Madenciliği Teknikleriyle İncelenmesi: 2011 İstanbul Örneği

In this study, 42 different types of high schools in Istanbul from which students took University Placement Exam (LYS) are clustered in terms of their performances. It was also aimed to determine the types of tests that are more efficient among these schools. For this purpose, educational data mining techniques such as clustering and decision tree are used. By deploying the non-hierarchical k-means algorithm, schools are separated into 5 different clusters which have different success level for each of Math-Science (MS), Language and Math (LM) and Language-Social Studies (LS) test scores. It is found that Science High Schools, Private Science High Schools, Anatolian High Schools and Anatolian Teacher Schools found to be in the highest achievement level in all of the test scores. Furthermore, constructed decision tree models with CHAID algorithm show that (1) Chemistry for the score type MS, (2) Math for the score type LM and (3) Turkish Language and Literature for the core type LS were the test types which are primarily effective in the division of schools into clusters.Bu çalışmada, İstanbul ilinde 2011 yılındaki LYS sınavına giren 42 farklı lise türü, başarı performanslarına göre kümelenmiş ve kümelere ayrışmada hangi test türlerinin etkili olduğu belirlenmiştir. Bu amaçlara yönelik eğitsel veri madenciliği metotlarından kümeleme ve karar ağacı teknikleri kullanılmıştır. Çalışma grubundaki okulların hiyerarşik olmayan k-means algoritmasıyla MF, TS ve TM puan türlerinin her biri için farklı başarı seviyelerini gösteren 5 kümeye ayrıştığı görülmüştür. Fen Lisesi, Özel Fen Liseleri, Anadolu Liseleri ve Anadolu Öğretmen Liselerinin tüm test türleri için en yüksek başarı seviyesini gösteren kümede yer aldığı bulunmuştur. Ayrıca CHAID algoritmasıyla oluşturulan karar ağacı modellerinde okulların kümelere ayrışmasında (1) MF için Kimya testinin (2) TM için Matematik testinin (3) TS için Türk Dili ve Edebiyatı testinin birinci derece etkili olduğu belirlenmiştir

A comparative study of conventional visual servoing schemes in microsystem applications

This paper presents an experimental comparison of conventional (calibrated and uncalibrated) image based visual servoing methods in various microsystem applications. Both visual servoing techniques were tested on a microassembly workstation, and their regulation and tracking performances are evaluated. Calibrated visual servoing demands the optical system calibration for the image Jacobian estimation and if a precise optical system calibration is done, it ensures a better accuracy, precision and settling time compared with the uncalibrated approach. On the other hand, in the uncalibrated approach, optical system calibration is not required and since the Jacobian is estimated dynamically, it is more flexible

Endovascular management of renal angiomyolipomas: Do coils have a benefit in terms of clinical success rates?

PURPOSEThis study evaluated single center results of endovascular treatment in renal angiomyolipoma (AML) to determine whether there is clinical relevance of adding proximal coil embolization to distal particle embolization in terms of safety, efficacy and retreatment rates.METHODSA retrospective analysis was performed to evaluate patients undergoing transarterial embolization for renal AMLs from January 2007 to October 2020. Parameters regarding patient and tumor characteristics, embolization technique, treatment outcome and complications were recorded. Patients were divided into two groups as A (only particle group) and B (particle + coil group) based on the type of embolic agent used for treatment. Comparative analysis was performed between the two groups in terms of tumor size reduction, retreatment and complication rates.RESULTForty-two patients (37 (88.1%) female, 5 (11.9%) male) harboring 48 AMLs were included in the study. The mean age was 43.46 (range 20 to 78). The technical success rate was 95.8% (46 of 48 procedures). The mean size reduction was 1.94±1 cm (p < 0.001) after treatments however, no significant difference was seen between groups in terms of tumor size reduction. Retreatment rates were 3.1% (1 of 32 cases) in group A and 14.3% (2 of 14 cases) in group B (p = 0.21). No significant difference was found between groups in terms of bleeding and complication rates during the perioperative period. Mean follow-up duration was 26.48±25.71 (range from 2 to 102) months. CONCLUSIONIn this study, no clear supplementary benefit was observed in terms of safety, and efficacy with the adjunction of coils to distal particle embolization in the management of AMLs

Renal complications of lipodystrophy: A closer look at the natural history of kidney disease

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144612/1/cen13732_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144612/2/cen13732.pd

Kamu Yöneticilerinin Siyasal Ve Yönetsel Ahlaki Davraniş Tipleri

Çalışmada siyasal-yönetsel ahlak ve siyasal-yönetsel yozlaşma kavramları incelenmiştir. Siyasi ve yönetsel yozlaşamaya sebep olan ahlaki tavırları açıklayabilmek için bireyin ahlak gelişimini anlatan teoriler üzerinde durulmuştur. Günümüz Türkiye’sindeki siyasi ve yönetsel yozlaşmalar sadece bugüne ait olmayıp geçmişten günümüze miras olarak gelmişlerdir. Bu durumun nedeni de ülkenin geçirmiş olduğu siyasi kültürel ve ekonomik değişimler olarak açıklanabilir

Association Between Androgen Deprivation Therapy and Mortality Among Patients With Prostate Cancer and COVID-19

Importance: Androgen deprivation therapy (ADT) has been theorized to decrease the severity of SARS-CoV-2 infection in patients with prostate cancer owing to a potential decrease in the tissue-based expression of the SARS-CoV-2 coreceptor transmembrane protease, serine 2 (TMPRSS2). Objective: To examine whether ADT is associated with a decreased rate of 30-day mortality from SARS-CoV-2 infection among patients with prostate cancer. Design, Setting, and Participants: This cohort study analyzed patient data recorded in the COVID-19 and Cancer Consortium registry between March 17, 2020, and February 11, 2021. The consortium maintains a centralized multi-institution registry of patients with a current or past diagnosis of cancer who developed COVID-19. Data were collected and managed using REDCap software hosted at Vanderbilt University Medical Center in Nashville, Tennessee. Initially, 1228 patients aged 18 years or older with prostate cancer listed as their primary malignant neoplasm were included; 122 patients with a second malignant neoplasm, insufficient follow-up, or low-quality data were excluded. Propensity matching was performed using the nearest-neighbor method with a 1:3 ratio of treated units to control units, adjusted for age, body mass index, race and ethnicity, Eastern Cooperative Oncology Group performance status score, smoking status, comorbidities (cardiovascular, pulmonary, kidney disease, and diabetes), cancer status, baseline steroid use, COVID-19 treatment, and presence of metastatic disease. Exposures: Androgen deprivation therapy use was defined as prior bilateral orchiectomy or pharmacologic ADT administered within the prior 3 months of presentation with COVID-19. Main Outcomes and Measures: The primary outcome was the rate of all-cause 30-day mortality after COVID-19 diagnosis for patients receiving ADT compared with patients not receiving ADT after propensity matching. Results: After exclusions, 1106 patients with prostate cancer (before propensity score matching: median age, 73 years [IQR, 65-79 years]; 561 (51%) self-identified as non-Hispanic White) were included for analysis. Of these patients, 477 were included for propensity score matching (169 who received ADT and 308 who did not receive ADT). After propensity matching, there was no significant difference in the primary end point of the rate of all-cause 30-day mortality (OR, 0.77; 95% CI, 0.42-1.42). Conclusions and Relevance: Findings from this cohort study suggest that ADT use was not associated with decreased mortality from SARS-CoV-2 infection. However, large ongoing clinical trials will provide further evidence on the role of ADT or other androgen-targeted therapies in reducing COVID-19 infection severity