Topic modeling and improvement of image representation for large-scale image retrieval

Tu, N.A.,Dinh, D.L.,Rasel, M.K.,Lee, Y.K. North-Holland [etc ; Elsevier Science Ltd 2016 Information sciences Vol.366 No.-

<P>In this paper, we present a new visual search system for finding similar images in a large database. However, there are a number of challenges regarding the robustness of the image representations and the efficiency of the retrieval framework. To tackle these challenges, we first propose an encoding technique based on soft-assignment of local features to convert an entire image into a single vector, which is a compact and discriminative representation. This encoded vector is suitable for most types of efficient indexing methods to produce an initial result. To compensate for the lack of incorporating geometric and object-related information during the encoding scheme, we then propose a probabilistic topic model to formalize the spatial structure among the local features. Moreover, the topic model allows us to effectively extract the object and background regions from the image. This is performed by a Markov Chain Monte Carlo algorithm for approximate inference. Finally, benefiting from the extracted objects in each image, we present a re-ranking scheme to automatically refine the initial search results. Our proposed retrieval framework has two major advantages: i) an aggregation strategy through soft-assignment improves the discriminative power of the representation, which has a determinative effect on the retrieval precision; and ii) the probabilistic latent topic model enables us to not only gain insight into the spatial structure of the image, but also handle a large variation in the object appearance. The experimental results from four benchmark datasets show that our approach provides competitive accuracy, and runs about ten times faster. Our studies also verify that proposed approach works effectively on large-scale databases of millions of images. (C) 2016 Elsevier Inc. All rights reserved.</P>

Does Quantitative Tibial Ultrasound Predict Low Bone Mineral Density Defined by Dual Energy X-Ray Absorptiometry?

Hakan Tuna,Murat Birtane,Galip Ekuklu,Fikret Cermik,Filiz Tuna,Siranus Kokino 연세대학교의과대학 2008 Yonsei medical journal Vol.49 No.3

Purpose: Efforts for the early detection of bone loss and subsequent fracture risk by quantitative ultrasound (QUS), which is a non-invasive, radiation free, and cheaper method, seem rational to reduce the management costs. We aimed in this study to assess the probable correlation of speed of sound (SOS) values obtained by QUS with bone mineral density (BMD) as measured by the gold standard method, dual energy X-ray absorptiometry (DEXA), and to investigate the diagnostic value of QUS to define low BMD. Materials and Methods: One hundred twenty-two postmenopausal women having prior standard DEXA measurements were included in the study. Spine and proximal femur (neck, trochanter and Ward's triangle) BMD were assessed in a standard protocol by DEXA. The middle point of the right tibia was chosen for SOS measurement by tibial QUS. Results: The SOS values were observed to be significantly higher in the normal BMD (t score >-1) group at all measurement sites except for the lumbar region, when compared with the low BMD group (t score <-1). SOS was negatively correlated with age (r=-0.66) and month since menopause (r=-0.57). The sensitivity, specificity, and positive and negative predictive values for QUS t score to diagnose low BMD did not seem to be satisfactory at either of the measurement sites. Conclusion: Tibial SOS was correlated weakly with BMD values of femur and lumbar spine as measured by DEXA and its diagnostic value did not seem to be high for discriminating between normal and low BMD, at these sites.

Effective and Reliable Speed Control of Permanent Magnet DC (PMDC) Motor under Variable Loads

Tuna, Murat,Fidan, Can Bulent,Kocabey, Sureyya,Gorgulu, Sertac The Korean Institute of Electrical Engineers 2015 Journal of Electrical Engineering & Technology Vol.10 No.5

This paper presents the effective and reliable speed control of PMDC motors under variable loads and reference speeds. As is known DC motors are more preferred in industrial practices. This is that, the PMDC motors don’t require brush and commutator care and to increase in torque per motor depending on developments in power electronics. In this study, proportional-integral controller (PI) and fuzzy logic controller (FL) have been designed for speed control of PMDC motor. In the design of these controllers, characteristics such as minimum overrun time, response time to the load, settling time and ideal rise time have been taken into consideration for better stability performance. In this design, the best system response was searched by examining the effect of different defuzzification methods onto the fuzzy logic system response. In conclusion, it has been seen that FL controller has a better performance for variable speed-load control of PMDC motor compared to PI controller.

Evaluation of corrosion resistance of Co-Cr alloys fabricated with different metal laser sintering systems

Tuna, Suleyman Hakan,Karaca, Erhan,Aslan, Ismail,Pekkan, Gurel,Pekmez, Nuran Ozcicek The Korean Academy of Prosthodonitics 2020 The Journal of Advanced Prosthodontics Vol.12 No.3

PURPOSE. The aim of this study was to evaluate the corrosion resistance of the specimens produced by five different commercial metal laser sintering (MLS) systems with their recommended Co-Cr alloy powders. MATERIALS AND METHODS. The MLS machines and the alloy powders used were, ProX 100-ST2724G (St-Pro), Mysint 100-EOS SP2 (SP2-Mys), EOSINT 270-EOS SP2 (SP2-EOS), SLM 100-Starbond CoS (SB-SLM), and MLab Cusing-Remanium<SUP>®</SUP> Star (RS-MLab), respectively. Eight specimens from each group were prepared. Open circuit potential (E<SUB>ocp</SUB>) and electrochemical impedance spectroscopy (EIS) measurements of polished surfaces of the specimens were conducted in a three-electrode cell using a potentiostat-galvanostat in Fusayama-Meyer artificial saliva (AS). Specimens from each group were immersed in AS and de-ionized water for seven days. E<SUB>ocp</SUB>, charge transfer resistance (R<SUB>ct</SUB>) values, and released ions (㎍/㎠ × 7d) in different solutions were determined. The specimen surfaces were observed with SEM/EDS. Results were analyzed statistically. RESULTS. E<SUB>ocp</SUB> values have shifted to potentials that are more positive over time. Steady-state E<SUB>ocp</SUB> values were from high to low as follows, SB-SLM, SP2-Mys, SP2-EOS, RS-MLab, and ST-Pro, respectively. After 60 mins, RS-MLab specimens had the highest R<SUB>ct</SUB> value, followed by SP2-Mys, SB-SLM, SP2-EOS, and ST-Pro. In all groups, ion release was higher in AS than that in de-ionized water. CONCLUSION. There were small differences among the corrosion resistances of the Co-Cr alloy specimens produced with MLS systems; meanwhile, the corrosion resistances were quite high for all specimens.

Effectiveness of Online Education in Teaching Breast Self-Examination

Tuna, Arzu,Avdal, Elif Unsal,Yucel, Sebnem Cinar,Dal, Nursel Alp,Dicle, Aklime,Ozkan, Arife,Sezgin, Handan,Gumus, Aysun Babacan,Turgay, Ayse San,Degirmenci, Mustafa Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.7

Background: This research evaluated the effectiveness of an online education model in teaching breast self-examination to university staff and students. Materials and Methods: 1,679 women participated in a breast self-examination online training program. Breast self-examination knowledge evaluation forms developed by Maurer (1997) were used in the research and were evaluated on a 100 point scale. Paired t-test and McNemar's Test statistics were employed. Results: The participants scored an average of 46.5 (14.0%) on knowledge on breast self-examination before training, but 77.4 (11.0%) one month after education and 76.7 (9.52%) after six months. There was a clear significant difference between these knowledge levels (p<0.05). Similarly, while the rate for systematic practice of breast self-examination among women was 30.8% before training it increased to 47.8% afterwards. Again the difference was significant (p<0.05). Conclusions: Online education is an effective method for teaching breast self-examination to women.

Effect of spodumene addition on pyroplastic deformation of porcelain stoneware

Tuna AYDIN 한양대학교 세라믹연구소 2014 Journal of Ceramic Processing Research Vol.15 No.6

Lithium aluminosilicates, such as spodumene, have been used as raw materials in the production of thermal shock resistant whiteware and sanitaryware. The presence of spodumene causes enhancement of mullitization and imparts better physical and mechanical properties to ceramics. In this study, the influence of Li2O-content on the properties of a standard porcelain stoneware body was investigated. Sodium feldspar was replaced by the spodumene in varying amounts (up to 4 wt. %). The results showed a significant microstructural improvement, the presence of spodumene which, during firing, allows the development of a low viscosity liquid phase with a decrease of closed porosity, also with increasing bulk density and bending strength.

Neutron shielding characteristics of polymer composites with boron carbide

Tuna Tuncay,Eker Aysegul Akdogan,Kam Erol 한국물리학회 2021 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.78 No.7

In this study, the neutron shielding capabilities of boron carbide ( B4C)-reinforced polyester-matrix composite materials were investigated. For the study, 20- 40- and 60-mm-thick specimens were first prepared by reinforcing with 10–50% B4C, and later their neutron shielding characteristics were studied by using various characterization techniques. The shielding capability of the composite materials was observed to increase with specimen thickness. In addition, increased amounts of B4C reinforcement improved the attenuation ratio of the material thereby increasing the shielding effectiveness. This trend, however, changed when the B4C ratio reached 40% and 50% at which a gradual decrease in neutron attenuation was observed. The experimental setup was also simulated using the Monte Carlo code MCNP-5, and similar computations were carried out. The experimental data almost completely agreed with computational results.

Unilateral Posterior Surgery for Severe Osteoporotic Vertebrae Fractures’ Sequelae in Geriatric Population: Minimum 5-Year Results of 109 Patients

Tuna Pehlivanoglu,Yigit Erdag,Ismail Oltulu,Umut Dogu Akturk,Emre Korkmaz,Kerem Yildirim,Ender Sarioglu,Kerem Gun,Ender Ofluoglu,Mehmet Aydogan 대한척추신경외과학회 2021 Neurospine Vol.18 No.2

Objective: This study aimed to evaluate the efficacy and safety of modified posterior vertebral column resection (PVCR) combined with anterior column restoration in elderly patients presenting with thoracic or thoracolumbar osteoporotic fractures with spinal cord compression and severe pain. Methods: One hundred nine patients with one level thoracolumbar osteoporotic fracture and at least 5 years of follow-up were included. They underwent posterior instrumentation performed with polymethymetachrylate augmented pedicle screws. A modified PVCR (unilateral costotransversectomy+hemilaminectomy) combined with the insertion of an expandable titanium cage for anterior column restoration was undertaken. Patients were evaluated clinically and radiographically. Results: Patients had a mean age of 74.1 and a follow-up duration of 92.3 months. Mean duration of operations, hospital stays, and mean loss of blood were 172.3 minutes, 4.3 days, and 205.4 mL. All of the patients were mobilized immediately after surgery. The mean preoperative local kyphosis angle improved from 39.3° to 4.7° at the last follow-up (p=0.003). Patients preoperative mean visual analogue score, Japanese Orthopaedic Association, and Oswestry Disability Index scores improved from 7.7/8.6/76.3 to 1.6/26.1/17.4 (p<0.001 for all), respectively. The average 36-item Short-Form survey physical component summary/mental component summary scores at the last follow-up were 55.1/56.8. A dural tear was detected intraoperatively in 1 patient and repaired immediately. Conclusion: Subtotal PVCR combined with the insertion of an expandable titanium cage was detected as a safe and effective method for osteoporotic vertebrae fractures’ sequelae in the older population involving spinal cord compression by enabling the decompression of the spinal canal and reconstruction of the resected segment, resulting in significant improvement in clinical and radiographic outcomes.

The effect of adenosine triphosphate on propofol-induced myopathy in rats: a biochemical and histopathological evaluation

Kezban Tuna Ozkaloglu Erdem,Zehra Bedir,Irem Ates,Ufuk Kuyrukluyildiz,Taha Abdulkadir Coban,Gulce Naz Yazici,Yusuf Kemal Arslan,Zeynep Suleyman,Halis Suleyman 대한약리학회 2021 The Korean Journal of Physiology & Pharmacology Vol.25 No.1

Propofol infusion syndrome characterized by rhabdomyolysis, metabolic acidosis, kidney, and heart failure has been reported in long-term propofol use for sedation. It has been reported that intracellular adenosine triphosphate (ATP) is reduced in rhabdomyolysis. The study aims to investigate the protective effect of ATP against possible skeletal muscle damage of propofol in albino Wistar male rats biochemically and histopathologically. PA-50 (n = 6) and PA-100 (n = 6) groups of animals was injected intraperitoneally to 4 mg/kg ATP. An equal volume (0.5 ml) of distilled water was administered intraperitoneally to the P-50, P-100, and HG groups. One hour after the administration of ATP and distilled water, 50 mg/kg propofol was injected intraperitoneally to the P-50 and PA-50 groups. This procedure was repeated once a day for 30 days. The dose of 100 mg/kg propofol was injected intraperitoneally to the P-100 and PA-100 groups. This procedure was performed three times with an interval of 1 days. Our experimental results showed that propofol increased serum CK, CK-MB, creatinine, BUN, TP I, ALT, AST levels, and muscle tissue MDA levels at 100 mg/kg compared to 50 mg/kg and decreased tGSH levels. At a dose of 100 mg/kg, propofol caused more severe histopathological damage compared to 50 mg/kg. It was found that ATP prevented propofol-induced muscle damage and organ dysfunction at a dose of 50 mg/kg at a higher level compared to 100 mg/kg. ATP may be useful in the treatment of propofol-induced rhabdomyolysis and multiple organ damage.

The Behavior Rating Inventory of Executive Function and Continuous Performance Test in Preschoolers with Attention Deficit Hyperactivity Disorder

H. Tuna Cak,S. Ebru Cengel Kultur,Bahar Gokler,Ferhunde Oktem,Candan Taskiran 대한신경정신의학회 2017 PSYCHIATRY INVESTIGATION Vol.14 No.3

Objective-The aim of this study is to examine performance-based measures and behavioral ratings of executive functions (EF) as a component of preschool attention deficit hyperactivity disorder (ADHD). Methods-Twenty-one 4-to-6-year-old children with ADHD and 52 children with no psychopathology, matched on age, gender, socioeconomic status, and parental education, were enrolled. Parents were interviewed with the use of The Schedule for Affective Disorders and Schizophrenia for School-Age Children Present and Lifetime version. The Conners’ Kiddie Continuous Performance Test (K-CPT) was administered to the children, and the Behavior Rating Inventory of Executive Function-Preschool version (BRIEF-P) and the Conners’ Parent Rating Scale-Revised/Short Form (CPRS-R/S) were filled out by the parents. Results-All BRIEF-P and CPRS-R/S scores, the K-CPT measures of inattention and impulsivity were higher in the ADHD group. The CPRS-R/S ADHD index was strongly correlated with inhibition and related indexes in the BRIEF-P and was moderately correlated with inattention measures in the K-CPT. Conclusion-The current study is one of the few to investigate the features of preschool ADHD with the use of behavioral ratings of EF and a performance-based measure. Our results suggest that the BRIEF-P was able to identify behavioral difficulties in inhibition and working memory and that the K-CPT identified difficulties indicating inattention. The findings of this study support the use of a combination of methods for a complete evaluation of preschoolers with inattentive and hyperactive/impulsive behavior, the application of rating scales for screening ADHD symptoms, and the measurement of behavioral correlates of EF, along with performance-based measures.