Audio Event Detection using Weakly Labeled Data

Acoustic event detection is essential for content analysis and description of multimedia recordings. The majority of current literature on the topic learns the detectors through fully-supervised techniques employing strongly labeled data. However, the labels available for majority of multimedia data are generally weak and do not provide sufficient detail for such methods to be employed. In this paper we propose a framework for learning acoustic event detectors using only weakly labeled data. We first show that audio event detection using weak labels can be formulated as an Multiple Instance Learning problem. We then suggest two frameworks for solving multiple-instance learning, one based on support vector machines, and the other on neural networks. The proposed methods can help in removing the time consuming and expensive process of manually annotating data to facilitate fully supervised learning. Moreover, it can not only detect events in a recording but can also provide temporal locations of events in the recording. This helps in obtaining a complete description of the recording and is notable since temporal information was never known in the first place in weakly labeled data.Comment: ACM Multimedia 201

Prevalence of apical periodontitis and endodontic treatment in a Kosovar adult population

<p>Abstract</p> <p>Background</p> <p>Despite numerous studies on the prevalence of apical periodontitis (AP) and endodontic treatment in diverse geographical populations, there are currently no data on the prevalence of these conditions in populations of adults native to Kosovo. Therefore, little is known about how widespread these conditions are, and whether there is any correlation between root canal treatment and AP. The purpose of our research was to address this anomaly by investigating AP and endodontic treatment in an adult Kosovar population based on radiographic examination.</p> <p>Methods</p> <p>The sample used for this study consisted of randomly selected individuals referred to the University Dentistry Clinical Center of Kosovo in the years 2006-2007. Orthopantomographs of 193 patients were evaluated. The periapical status of all teeth (with the exception of third molars) was examined according to Ørstavik's Periapical Index. The quality of the root canal filling was rated as 'adequate' or 'inadequate' based on whether all canals were filled, the depth of fill relative to the radiographic apex and the quality of compaction (absence/presence of voids). Data were analyzed statistically using the Chi-square test and calculation of odds ratios.</p> <p>Results</p> <p>Out of 4131 examined teeth, the prevalence of apical periodontitis (AP) and endodontic treatment was 12.3% and 2.3%, respectively. Of 95 endodontically-treated teeth, 46.3% were associated with AP. The prevalence of AP increased with age. The prevalence in subjects aged over 60 years old (20.2%) was higher than in other age groups. A statistically significant difference was found for the frequency of endodontically-treated teeth associated with AP in the 40-49 year age group (P < 0.001). Of some concern was the discovery that only 30.5% of the endodontically-treated teeth examined met the criteria of an acceptable root canal filling. Inadequately root-filled teeth were associated with an increased AP risk.</p> <p>Conclusions</p> <p>The prevalence of AP and the frequency of endodontically-treated teeth with AP in this Kosovar population are higher than those found in other countries. Inadequate root canal fillings were associated with an increased prevalence of AP.</p

Effects of initial fattening age on carcass characteristics and meat quality in Simmental bulls imported from Austria to Turkey

The aim of this study was to determine the effects of initial fattening age on carcass and meat quality of Simmental bulls imported from Austria to Turkey. These animals were allocated to two initial ages of fattening groups, namely young (n = 74) and old group (n = 61) at 5.5 and 7.5 months old, respectively. After reaching the target final weights, the animals were slaughtered and the carcass characteristics, area and circumference of the longissimus thoracis et lumborum (LTL) muscle, marbling score, and meat quality, including cooking loss, water-holding capacity (WHC), shear force (WBSF), and colour parameters were evaluated in six animals per group. A comparison of hot and cold carcass weights and dressing percentages, LTL circumference, fat thickness values and marbling score indicated no significant differences between young and old groups. However, the LTL area was significantly affected by the initial age. There were no significant differences between groups in WHC, cooking loss, and WBSF values and meat colour parameters. The results of this study showed that the initial fattening age of bulls showed no significant effect on carcass and meat quality parameters, except the LTL area. The LTL area was significantly higher in young group than the old group. Further studies are needed to improve carcass and meat quality of imported Simmental bulls through modifying the initial fattening age.Keywords: Age, beef, carcass quality, Simmenta

A strategy to enhance AGC performance of power systems that suffer inter-area oscillations and a case study for Turkish power system

Sufficient fast secondary reserve and its adequate dynamic activation are the key factors in satisfying automatic generation control (AGC) performance of a power system. Dynamic activation of the secondary reserves should also not introduce any negative damping to inter-area oscillations. This study presents a strategy to enhance AGC performance of a power system considering these concerns. Objective function is minimizing the amount of fast secondary reserves to mitigate ancillary service cost. The constraints are; AGC performance indices should be acceptable and AGC parameter settings should be adequate for inter-area oscillation concerns. In order to facilitate dynamic simulations, it is proposed to utilize a representative single bus common frequency dynamic model (SBCFDM) of the power system. The proposed strategy is based on optimizing the AGC parameters only for the time horizon when the loads are fluctuating most. Adequacy of the optimized AGC parameters are checked only for the worst loading scenario from inter-area oscillations concern point of view. It is showed that dynamic allocation of the secondary reserves twice a day is sufficient for satisfactory results. The proposed strategy is verified by its application to Turkish power system which suffers significant amount of fluctuating loads and inter-area oscillations with ENTSO/E grid

Assessment of the effect of hydroelectric power plants' governor settings on low frequency inter area oscillations

The Turkish TSO (TEIAS) has been leading a project that aims the synchronous interconnected operation of the Turkish Power System and the ENTSO-E CESA (former UCTE) System. For this purpose, this study concentrates on the specific problems related to the electromechanical systems of large size hydroelectric power plants regarding low frequency inter area oscillations, which are prone to occur once the interconnected operation is established. The expected frequency of inter area oscillations after interconnected operation is close to 0.15 Hz, which is in the frequency range of the speed governing structures of turbines, as explained in the first two sections of the thesis. In the third section, the nonlinear turbine governor model used throughout the study is explained. In the following part, the governor parameter tuning study with regard to the defined performance objectives is explained. Afterwards, the effect of the retuned governor settings of the sample hydroelectric power plants on a simple multi machine power system is shown. Following that, the system wide effect of removing the sources of negative damping, which are strongly dependent on the governor settings of the major hydroelectric power plants of the Turkish Power System, is shown. In the final part, conclusions are made on the operation of the hydroelectric power plants regarding the frequency stability of the system after synchronous interconnected operation of the v Turkish Power System and the ENTSO-E CESA System.Türkiye iletim sistemi operatörü TEIAS, Türkiye İletim Sistemi ve ENTSO-E CESA (eski adıyla UCTE) sistemlerinin senkron paralel bağlantısını amaçlayan bir proje yürütmektedir. Bu amaçla yürütülen çalışmaların ışığında, bu çalışmada, Türkiye Elektrik Sistemi’ndeki büyük güçteki hidroelektrik santrallerin hız regülatörü ayarlarının, bağlantı sonucu oluşması muhtemel bölgeler arası salınımlara etkisi üzerine yoğunlaşılmıştır. İki iletim sisteminin senkron parallel bağlantısının ardından oluşması muhtemel bölgeler arası salınımların frekansı 0.15 Hz civarındadır ki, bu çalışmanın ilk iki bölümünde gösterildiği üzere, bahsedilen salınım frekansı, üretim tesislerinin hız regülatörleri ve türbinlerinin de tepkisel olduğu frekans bandına denk gelmektedir. Çalışmanın üçüncü bölümünde, bölgeler arası salınımların sistem frekans kararlılığı üzerindeki olumsuz etkilerini asgariye indirmeyi amaçlayan hidroelektrik santral hız regülatörü ayarlarına ulaşmak için kullanılan türbin ve hız regülatörü modelleri açıklanmıştır. Çalışmanın dördüncü bölümünde, sistemin üretim tüketim dengesizliği durumundaki davranışını da gözeterek, bölgeler arası salınımların sistem frekans kararlılığı üzerindeki olumsuz etkilerini asgariye indirmeyi amaçlayan hidroelektrik santral hız regülatörü ayarlarının tespit edilme yöntemi açıklanmış ve bu yöntemle elde edilen hız regülatörü ayarlarının frekans vii kararlılığı üzerindeki etkisi çok makineli bir güç sisteminde gösterilerek, önerilen ayarların sistem işletimine uygun olduğu sonucuna varılmıştır. Sonrasında, Türkiye Elektrik Sistemi’ndeki bütün büyük güçteki hidroelektrik santraller için, önerilen yöntemle elde edilen hız regülatörü ayarlarının sistem genelindeki sönümlendirme performansını arttırıcı etkisi gösterilmiştir. Çalışmanın son bölümünde, ENTSO-E CESA sistemi ile senkron parallel bağlantı sonrasında, hidroelektrik santrallerin sistem frekans kararlılığı gözetilerek işletilmesi noktasında elde edilen sonuçlar ifade edilmiştir

A geographical zoning methodology for nodal transmission use-of-system tariffs

Power systems are generally separated into transmission use-of-tariff (TUoT) zones to simplify the tariff mechanism, particularly for large grids. Each zone is an aggregation of neighboring nodes with similar tariffs that are determined based on long-run marginal cost (LRMC) calculations. This paper proposes a zoning methodology which ensures diversification of zonal tariffs while geographically aggregating the nodal TUoTs by weighted average approach. Investment cost-related pricing (ICRP) and DC-load-flow pricing (DCLFP) methods are utilized in computing the LRMC based nodal tariffs. Performance of the LMRC based pricing methods, sensitivity of the economical parameters on the results, and the proposed zoning approach are investigated for a simple 12-bus generic power system. Given the satisfactory results, TUoT zones of Turkish power network are determined with the proposed zoning algorithm for the tariff period of 2012-2014

A Geographical Zoning Methodology for Nodal Transmission Use-of-System Tariffs

Power systems are generally separated into transmission use-of-tariff (TUoT) zones to simplify the tariff mechanism, particularly for large grids. Each zone is an aggregation of neighboring nodes with similar tariffs that are determined based on long-run marginal cost (LRMC) calculations. This paper proposes a zoning methodology which ensures diversification of zonal tariffs while geographically aggregating the nodal TUoTs by weighted average approach. Investment cost-related pricing (ICRP) and DC-load-flow pricing (DCLFP) methods are utilized in computing the LRMC based nodal tariffs. Performance of the LMRC based pricing methods, sensitivity of the economical parameters on the results, and the proposed zoning approach are investigated for a simple 12-bus generic power system. Given the satisfactory results, TUoT zones of Turkish power network are determined with the proposed zoning algorithm for the tariff period of 2012-2014