128 research outputs found
Formation control of a group of micro aerial vehicles (MAVs)
Coordinated motion of Unmanned Aerial Vehicles (UAVs) has been a growing research interest in the last decade. In this paper we propose a coordination model that makes use of virtual springs and dampers to generate reference trajectories for a group of quadrotors. Virtual forces exerted on each vehicle are produced by using projected distances between the quadrotors. Several coordinated task scenarios are presented and the performance of the proposed method is verified by simulations
A modular software architecture for UAVs
There have been several attempts to create scalable and hardware independent software architectures for Unmanned Aerial Vehicles (UAV). In this work, we propose an onboard architecture for UAVs where hardware abstraction, data storage and communication between modules are efficiently maintained. All processing and software development is done on the UAV while state and mission status of the UAV is monitored from a ground station. The architecture also allows rapid development of mission-specific third party applications on the vehicle with the help of the core module
Orosanga japonica (Melichar, 1898) (Hemiptera: Ricaniidae)’nın nimf ve erginlerine karşı Cuscuta campestris Yunck. (Solanales: Convolvulaceae) ve Lupinus albus L. (Fabales: Fabaceae) bitki ham özütlerinin laboratuvar koşulları altında toksik etkinliği
The planthopper, Orosanga japonica (Melichar, 1898) (Hemiptera: Ricaniidae), is an important agricultural pest of grapevine, kiwifruit and tea in Asia and in some countries of Eastern Europe. The efficacy of the crude extracts of Cuscuta campestris Yunck. (Solanales: Convolvulaceae) and Lupinus albus L. (Fabales: Fabaceae) plants was evaluated under laboratory conditions for control of O. japonica nymphs and adults collected in 2019 from Rize (Turkey). Their toxic efficacies were investigated by two different methods. Fixed-dose death rates were used for LT50 calculation and dosage test results were used for LC50 calculation. Also, the phenolic constituents of active plant extracts were examined using HPLC-DAD. Generally, the LT50 values obtained using ethyl acetate extracts were lower than those with methanol extracts. LT50 values of adults were found lower than in nymphs. The test plants crude extracts had high activity at and below 2 g/L (LC90) for two different plants. HPLC-DAD results showed that the high concentration of kaempferol and quercetin for each extract. Extracts of both plants gave promising results for use in O. japonica control, but more detailed studies on the active constituents of these candidate plants need to be undertaken
NOMA TABANLI BİLİŞSEL RADYO SİSTEMLERİNDE SİNİR AĞI YÖNTEMLERİ İLE ERGODİK KAPASİTE TAHMİNİ VE BAŞARIM ANALİZİ
Bu çalışmada, bilişsel radyo (BR) tabanlı dikgen olmayan çoklu erişim tekniği (NOMA) kullanılarak, yakın kullanıcıya ait toplam ergodik kapasite değerinin, önerilen ileri beslemeli geri yayılımlı yapay sinir ağı (YSA) ve doğrusal olmayan dışsal girdili otoregresif ağ (Nonlinear Autoregressive Network with Exogenous Inputs, NARX) modeli ile farklı eğitim algoritmaları yoluyla yüksek doğruluk oranında ve hızlı eğitim sürelerinde tahmin edilmesi amaçlanmıştır. Sinir ağında kullanılan veri seti, üstel sönümleme kanalı karakteristiği ile modellenen BR-NOMA sistem modelinden elde edilmiştir. Denetimli öğrenme yöntemi kullanılarak tasarlanan YSA’ya girdi ve çıktı verileri öğretilerek yakın kullanıcıya ait ergodik kapasite tahmini yapılmıştır. YSA ve NARX sinir ağları başarımı değerlendirilirken eğitim süresi, iterasyon sayısı, ağın doygunluğa ulaşmaması durumları göz önünde bulundurulmuştur. Yakın kullanıcıya ait gerçek ergodik kapasite değeri ile ileri beslemeli geri yayılımlı YSA ve NARX ağlarının tahmin etmiş olduğu değerler karşılaştırılmıştır. Önerilen sinir ağlarının Levenberg-Marquardt, Bayesian ve Scaled-Conjugate eğitim algoritmaları altındaki performans analizi, hatanın minimuma ulaştığı epok değer grafiği, hata histogram analizi ve eğitim durum analizi açılarından incelenmiştir
Türk kolon ve rektum cerrahisi derneği (TKRCD) terminoloji komisyonu çalışma raporu
This study aimed to explain the working order of the Terminology Commission, which was established at the workshop of the Turkish Society of
Colon and Rectal Surgery (TKRCD) on February 22, 2020, the criteria and results in the preparation of the terminology report. The commission
prepared a work plan to complete in three main steps. The working process continued in a way that the members expressed their opinions with equal
rights and the decisions were taken by consensus or by majority vote. The main purpose of the commission study was determined as “determining the
terms that need to be explained and agreed in colorectal surgery, and to define them in a way that is compatible with the literature and contributes to
daily practice”. The first meeting of the commission was held on February 22, 2020, and the report was accepted by the TKRCD Board of Directors
on May 25, 2021. A total of 20 meetings were held during this period. In the first step, five headings were determined for writing the terms: Anatomy,
symptoms and diagnostic tools, diseases, treatments and complications. There was a consensus that the terms met the following three conditions:
1) the need for explanation and consensus in colorectal surgery, 2) literature support, and 3) use in daily practice. The terms were written in the
following format: Terms and synonyms, English equivalents, definition, explanation and bibliography. In the second step, each commissioner wrote
an average of 10.8±4.3 terms. The distribution of 89 terms in the final report was as follows: Anatomy (n=26, 29.2%), symptoms and diagnostic
tools (n=8, 8.9%), diseases (n=20, 22.4%), treatments (n=28, 31.4%), and complications (n=7, 7.8%). Figures (n=7), all from the archives of the
commission members, and figures drawn by a new commission member (n=53) were also added to the report. In the third step, the report was
submitted to the TKRCD Management with the approval of the TKRCD President. The preparation process of the Terminology Commission report of
TKRCD was presented. The final report is open to changes and expansions with future studies.Bu çalışma Türk Kolon ve Rektum Cerrahisi Derneği’nin (TKRCD) 22 Şubat 2020 tarihinde yaptığı çalıştayda kurulan Terminoloji Komisyonu’nun çalışma düzenini, terminoloji raporunun hazırlanmasındaki kriterleri ve sonuçlarını açıklamayı amaçlamaktadır. Komisyon üç ana basamakta tamamlayacak iş planı hazırlamıştır. Çalışma süreci üyelerin eşit haklarla görüş belirttiği ve kararların uzlaşı veya oy çokluğuyla alındığı bir şekilde sürdürülmüştür. Komisyon çalışmasının temel amacı “kolorektal cerrahide açıklanması ve uzlaşı sağlanması gerekli terimlerin belirlenmesi, literatüre uygun ve günlük pratiğe katkı sağlayacak bir şekilde tanımlanması” olarak saptanmıştır. Komisyon ilk toplantısı 22 Şubat 2020’de yapılmış, rapor ise TKRCD Yönetim Kurulu’nda 25 Mayıs 2021’de kabul edilmiştir. Bu dönemde toplam 20 toplantı yapılmıştır. İlk basamakta terimlerin yazılması için beş adet üst başlık belirlenmiştir: anatomi, semptomlar ve tanı gereçleri, hastalıklar, tedaviler ve komplikasyonlar. Terimlerin şu üç şartı sağlaması konusunda karar birliği oluşmuştur: 1) kolorektal cerrahide açıklanması ve uzlaşı sağlanması gerekliliği, 2) literatür desteği ve 3) günlük pratikte kullanılması. Terimler şu formatta yazılmıştır: terim ve eş anlamlıları, İngilizce karşılıkları, tanım, açıklama ve kaynakça. İkinci basamakta her bir komisyon üyesi ortalama 10,8±4,3 terim yazmıştır. Sonuç raporunda yer alan 89 terimin üst başlıklara dağılımı şu şekildedir: anatomi (n=26, %29,2), semptomlar ve tanı gereçleri (n=8, %8,9), hastalıklar (n=20, %22,4), tedaviler (n=28, %31,4) ve komplikasyonlar (n=7, %7,8). Tamamı komisyon üyelerinin arşivlerinden gelen resimler (n=7) ve yeni bir komisyon üyesi tarafından çizilen şekiller de (n=53) rapora eklenmiştir. Üçüncü basamakta rapor TKRCD Başkanının onayıyla TKRCD Yönetimi’ne sunulmuştur. TKRCD’nin Terminoloji Komisyonu raporunun hazırlık süreci sunulmuştur. Sonuç raporu ileride yapılacak çalışmalarla değişiklik ve genişletmelere açıktır
Histopathologic Evaluation of Nonalcoholic Fatty Liver Disease in Hypothyroidism-Induced Rats
It is speculated that thyroid hormones may be involved in nonalcoholic fatty liver disease (NAFLD) pathogenesis. A literature scan, however, demonstrated conflicting results from studies investigating the relationship between hypothyroidism and NAFLD. Therefore, our study aims to evaluate NAFLD, from the histopathologic perspective, in hypothyroidism-induced rats. Wistar rats were divided into 2 groups: the experimental group consumed water containing methimazole 0.025% (MMI, Sigma, USA) for 12 weeks and the control group consumed tap water. At the end of week 12, serum glucose, ALT, AST, triglyceride, HDL, LDL, TSH, fT4, fT3, visfatin, and insulin assays were performed. Sections were stained with hematoxylin-eosin and "Oil Red-O" for histopathologic examination of the livers. In our study, we detected mild hepatosteatosis in all hypothyroidism-induced rats. There was statistically significant difference with respect to obesity between the two groups ( < 0.001). The mean fasting blood glucose was 126.25 ± 23.4 mg/dL in hypothyroidism-induced group and 102.63 ± 15.51 mg/dL in the control group, with a statistically significant difference between the groups ( = 0.032). The two groups did not differ statistically significantly with respect to visfatin levels ( > 0.05). In conclusion, we found that hypothyroidism-induced rats had mild hepatosteatosis as opposed to the control group histopathologically. Our study indicates that hypothyroidism can cause NAFLD
Histopathologic Evaluation of Nonalcoholic Fatty Liver Disease in Hypothyroidism-Induced Rats
It is speculated that thyroid hormones may be involved in nonalcoholic fatty liver disease (NAFLD) pathogenesis. A literature scan, however, demonstrated conflicting results from studies investigating the relationship between hypothyroidism and NAFLD. Therefore, our study aims to evaluate NAFLD, from the histopathologic perspective, in hypothyroidism-induced rats. Wistar rats were divided into 2 groups: the experimental group consumed water containing methimazole 0.025% (MMI, Sigma, USA) for 12 weeks and the control group consumed tap water. At the end of week 12, serum glucose, ALT, AST, triglyceride, HDL, LDL, TSH, fT4, fT3, visfatin, and insulin assays were performed. Sections were stained with hematoxylin-eosin and “Oil Red-O” for histopathologic examination of the livers. In our study, we detected mild hepatosteatosis in all hypothyroidism-induced rats. There was statistically significant difference with respect to obesity between the two groups (p<0.001). The mean fasting blood glucose was 126.25 ± 23.4 mg/dL in hypothyroidism-induced group and 102.63 ± 15.51 mg/dL in the control group, with a statistically significant difference between the groups (p=0.032). The two groups did not differ statistically significantly with respect to visfatin levels (p>0.05). In conclusion, we found that hypothyroidism-induced rats had mild hepatosteatosis as opposed to the control group histopathologically. Our study indicates that hypothyroidism can cause NAFLD
Classical Simulation of Relativistic Quantum Mechanics in Periodic Optical Structures
Spatial and/or temporal propagation of light waves in periodic optical
structures offers a rather unique possibility to realize in a purely classical
setting the optical analogues of a wide variety of quantum phenomena rooted in
relativistic wave equations. In this work a brief overview of a few optical
analogues of relativistic quantum phenomena, based on either spatial light
transport in engineered photonic lattices or on temporal pulse propagation in
Bragg grating structures, is presented. Examples include spatial and temporal
photonic analogues of the Zitterbewegung of a relativistic electron, Klein
tunneling, vacuum decay and pair-production, the Dirac oscillator, the
relativistic Kronig-Penney model, and optical realizations of non-Hermitian
extensions of relativistic wave equations.Comment: review article (invited), 14 pages, 7 figures, 105 reference
Attitudes of consumers with regards to advertisements of private hospitals: A study in Süleymanpasa, Tekirdag
Bu çalışmanın amacı özel hastanelerin reklamlarına ilişkin tüketicilerinin nasıl bir tutum içinde olduklarını tespit etmektir. Bu çalışmada Tekirdağ Süleymanpaşa merkez ilçesindeki özel hastaneleri tercih eden hasta ve hasta yakınları yanı sıra potansiyel sağlık hizmeti tüketicilerinin özel hastanelerin reklam faaliyetlerine karşı tutumları belirlenmiştir. Bu amaçla 426 kişiye anket uygulanmıştır. Elde edilen bilgiler SPSS istatistik programında düzenlenmiştir. Tanımlayıcı istatistikler özet tablo halinde verilmiştir. Likert tipi ifadelere ilişkin frekans ve yüzdelerin yanı sıra aritmetik ortalama ve standart sapma değerleri de hesaplanmıştır. Yapılan analizlerde t-test ve ANOVA kullanılmıştır. Sonuç olarak tüketicilerin özel hastane reklamlarını öğrendikleri kaynaklar “Belediye otobüslerindeki afiş ve reklamlar ile belediye otobüs duraklarındaki afişlerdir. Lise mezunları, işçiler ile 1-2 kez özel hastaneden hizmet alanlar özel hastane reklamlarına ilişkin daha olumlu tutuma sahiptirler. Eğitim seviyesi arttıkça özel hastane reklamlarına ilişkin tutumlar negatifleşmektedir.This study aims to determine the attitudes of the consumers toward the advertisements of private hospitals. Besides the relatives of patients who prefer private hospitals in Tekirdağ’s central district Süleymanpaşa, the potential health service consumers’ attitudes toward private hospital advertisements have been verified. In this respect, a survey was conducted on 426 people, and the results were organized in SPSS statistics program before they have been presented within a spreadsheet. Besides the Likert scale frequencies and percentages, arithmetic average and standard deviation values have also been calculated. T-test and ANOVA have been applied to the conducted analyses. The results show that the advertisements and posters on municipality buses and at bus stops are the sources of the consumers’ knowledge about private hospitals. High-school graduates, workers, and the ones who prefer private hospitals several times have more positive attitude toward these advertisements. It has been concluded that as the education level increases, the attitude toward private hospital advertisements becomes more negative
- …