Smart grid: service restoration in distribution power systems

Prilikom rešavanja problema obnavljanja pogona distributivnih sistema u postojećoj literaturi su uglavnom upotrebljavane ili modifikovane već poznate metode rešavanja problema iz drugih oblasti elektroenergetike. U radu je prezentovan pregled i opis postojećih načina rešavanja obnavljanja pogona U ovoj disertaciji je razvijen i verifikovan novi način rešavanja problema obnavljanja pogona. U disertaciji se razmatra problem obnavljanja pogona distributivnih sistema i u svetlu aktuelnih i globalnih napora kojim bi se postojeće elektroenergetske mreže transformisale u inteligentne elektroenergetske mreže. Iako postoji određeni broj konvencionalnih metoda i načina rešavanja obnavljanja pogona u distributivnim sistemima ipak novi koncept inteligentnih mreža zahteva usavršavanje postojećih kao i pronalaženje novih načina rešavanja ovog problema. Efikasno rešavanje obnavljanja pogona distributivnih sistema se u predloženoj temi ostvaruje pomoću algoritma koji je zasnovan na Primovom algoritmu, odnosno njegovoj modifikaciji. Primov algoritam, uključujući navedenu modifikaciju, je matematički detaljno opisan a zatim je primenljivost modifikovanog algoritma na rešavanje obnavljanja pogona distributivnih sistema sveobuhvatno analizirana. Iz toga proističe novi način rešavanja obnavljanja pogona distributivnih sistema koji se efikasno uklapa u širi koncept inteligentne mreže. Novi način rešavanja obnavljanja pogona je sastavni deo kompletno razvijenog algoritmom koji uključuje i proračune tokova snaga, rasterećenje preopterećenih elemenata prilikom rešavanja obnavljanja pogona kao i generisanje potrebnih prekidačkih akcija. Na kraju je razvijeni algoritam testiran na modelu složene distributivne mreže...Methods and approaches for the solving of the service restoration problem in the existing literature are based on well known methods that are also used for the solving of other problems in electrical power systems. Review of the methods and approaches is presented in this dissertation. New approach for the solving of the service restoration in distribution systems is developed and verified in this dissertation. The relation between the service restoration problem and transformation of conventional electrical power networks into smart grid are addressed in the dissertation. Although there is a number of known methodologies and approaches for solving the service restoration of the distribution power systems, an improvement of existing methodologies and approaches or research for new ones in order to accommodate the smart grid requirements are required. An effective service restoration approach proposed in the dissertation is based on modified Prim’s algorithm. Prim’s algorithm including its modification is mathematically described in details followed by comprehensive analysis of the modified Prim’s algorithm implementation to the solving of the service restoration. The new approach for the solving of the service restoration problem in distribution networks that can be incorporated into smart grid concept is derived from the analysis. Proposed new approach for the solving of the service restoration problem is incorporated in the developed algorithm. The algorithm also contains other typical distribution power system analysis tools such as load flow, load transfer from elements that are overloaded during the service restoration calculations, and the filtering of the required switching actions. The developed algorithm is tested on the complex model of the distribution network..

Optical Biopsy Method for Breast Cancer Diagnosis Based on Artificial Neural Network Classification of Fluorescence Landscape Data

Supervised self-organizing map, a type of artificial neural network, is applied for classification of human breast tissue samples utilizing data obtained from fluorescence landscape measurements. Female breast tissue samples were taken soon after the surgical resection, identified and stored at -80 degrees C until fluorescence measurements. From fluorescence landscapes obtained in UV-VIS region spectral features showing statistically significant differences between malignant and normal samples are identified and further quantified to serve as a training input to neural network. Additional set of samples was used as a test group input to trained network in order to evaluate performance of proposed optical biopsy method. Classification sensitivity of 83.9% and specificity of 88.9% are found

pi-pi and cation-pi interactions in protein-porphyrin complex crystal structures

In this study we have described the pi-pi and cation-pi interactions between the porphyrin ring and the protein part of porphyrin-containing proteins to better understand their stabilizing role. The number of pi-pi interactions was higher than that of cation-pi interactions in the same set of proteins studied. The pyrrole groups of one porphyrin can be involved in pi-pi interactions with pi systems of another porphyrin in the protein. We have found 5.1% cation-pi interactions between porphyrin Fe2+ metal cations and pi systems of surrounding amino acids as well as the pyrrole rings of other porphyrins. We observed that most of the pi-pi interactions have an energy in the range -0.5 to -2.0 kcal mol(-1), while the cation-pi interactions showed an energy in the range 22 to -4 kcal mol(-1). Further, an appreciable number of metal/cation-pi interaction pairs have an energy in the range -6 to -13 kcal mol(-1). The preferred parallel-stacked orientation is found to be more stable than a T-shaped structure for the full set of pi-pi interaction pairs. In the case of cation-pi interactions, it was found that 44% of the cation-pi interactions involved planar stacking, 37% of the interactions belonged to the oblique category, and the remaining 19% of the interactions were of the orthogonal type. The separation distance between the cation group and the aromatic ring decreases as the interplanar angle decreases. Furthermore, in the present study we have found that 10.4% of pi residues and 3.9% of cationic residues were found to have one or more stabilization centers. Amino acids deployed in the environment of porphyrin rings are deposited in helices and coils. The results from this study might be used for structure-based porphyrin protein prediction and as scaffolds for future porphyrin-containing protein design

A NON-INTRUSIVE IDENTIFICATION OF HOME APPLIANCES USING ACTIVE POWER AND HARMONIC CURRENT

In recent years, research on non-intrusive load monitoring has become very popular since it allows customers to better manage their energy use and reduce electrical consumption. The traditional non-intrusive load monitoring method, which uses active and reactive power as signatures, has poor performance in detecting small non-linear loads. This drawback has become more prominent because the use of nonlinear appliances has increased continuously during the last decades. To address this problem, we propose a NILM method that utilizes harmonic current in combination with the changes of real power. The advantages of the proposed method with respect to the existing frequency analysis based NILM methods are lower computational complexity and the use of only one feature to characterize the harmonic content of the current

Volumetric Analysis of Amygdala, Hippocampus, and Prefrontal Cortex in Therapy-Naive PTSD Participants

Objective. In our study we have hypothesized that volume changes of amygdala, hippocampus, and prefrontal cortex are more pronounced in male posttraumatic stress disorder participants. Material and Methods. We have conducted a study of 79 male participants who underwent MRI brain scanning. PTSD diagnosis was confirmed in 49 participants. After MRI was taken all scans were software based volume computed and statistically processed. Results. We found that left amygdala is the most significant parameter for distinction between PTSD participants and participants without PTSD. There were no significant differences in volumes of hippocampi and prefrontal cortices. Roc curve method outlined left amygdala AUC = 0.898 (95% CI = 0.830-0.967) and right amygdala AUC = 0.882 (95% CI = 0.810-0.954) in the group of PTSD participants which makes both variables highly statistically significant. Conclusion. The present investigation revealed significant volume decrease of left amygdala in PTSD patients. Concerning important functions of the amygdala and her neuroanatomical connections with other brain structures, we need to increase number of participants to clarify the correlation between impared amygdala and possible other different brain structures in participants with PTSD

UPLC-MS/MS determination of histamine levels in canned fish collected from Belgrade retail markets

The aim of this study was to determine the amount of histamine in canned fish samples collected from Belgrade retail stores using ultra-performance liquid chromatography tandem mass-spectrometry. In addition, the established levels were compared with the maximum levels set by US Food and Drug Administration (FDA) and European Union (EU) in order to assess the risk of this toxic biogenic amine to the city population. Histamine was detected in 54.07% of analyzed canned fish, in concentrations ranging from 5 to 420 mg/kg with a mean level of 60.91 mg/kg. In canned tuna, histamine levels ranged from 6 to 420 mg/kg, while in canned mackerel the concentrations ranged from 5 to 121 mg/kg. Also, the mean histamine level in canned tuna was higher than in canned mackerel (mean values were 60.91 mg/kg and 42.94 mg/kg, respectively). Among the tested canned fish, 20% of samples had higher histamine levels than the maximum level prescribed by the FDA (histamine levels >50 mg/kg), indicating definite decomposition of the fish. Histamine levels lower than 10 mg/kg were found in 51.48% of canned fish, which indicated good-quality fish products. Only 6.67% of examined production lots of canned fish had histamine levels above the regulatory limit according to the EU standard

Uticaj intenziteta parazitske infekcije sa Strongyloides papillosus i terapije albendazolom na biohemijske parametre u krvi ovaca

The aim of this report was to study the biochemical parameters in sheep blood under conditions of various intensities of parasitic infection with Strongyloides papillosus, as well as after therapy with albendazole (ABZ). Investigations were performed on sheep of the Würtemberg race (n = 30) in which were detected mild, moderate and high intensities of parasitic infection with S. papillosus. The control group (n = 10) was composed of sheep negative to parasitic infections. The degree and type of changes were monitored by determining the concentrations of glucose, total proteins, albumin, A/G ratio, AST, urea, total bilirubin, calcium, phosphorus, total LDH activity and isoenzymatic LDH1-5 distributions. On the basis of the obtained results, we determined, through isoenzymatic LDH distribution, that during parasitic infection with S. papillosus, there is ongoing damage to the liver, heart muscle and lung, while after therapy with ABZ, the liver suffers the most damage. The concentration of glucose, total proteins and albumin fell linearly with the rise in the intensity of parasitic infection (p LT 0.05), while after therapy with ABZ, the fall of these parameters was at a statistically significantly higher level (p LT 0.01). The activity of AST, concentration of urea and total bilirubin also rose linearly with the intensity of parasitic infection (p LT 0.05). After therapy with ABZ, the activity of AST and the concentration of total bilirubin were at a statistically significantly higher level (p LT 0.001), while the concentration of urea retained the same levels as in the case of parasitic infection. Values of calcium concentrations (p>0.05) and phosphorus (p LT 0.05) also fall linearly with the rise of the intesity of the parasitic infection. The trend in the concentration fall of these macroelements, continues also after treatment with albendazole (p LT 0.001). Having in mind our previous studies in the field of oxidative stress and phenomena lying behind these changes, we strongly recommend that in antiparasitic treatment protocols, beside antihelminthics, compounds with antioxidative properties should also be used.Cilj ovog rada je bio da se ispitaju biohemijski parametri u krvi ovaca u uslovima različitog intenziteta parazitske infekcije sa Strongyloides papillosus, kao i nakon terapije sa albendazolom (ABZ). Istraživanje je izvedeno na ovcama Wurtemberg rase (n = 30) kod kojih je utvrđen blagi, srednji i visoki intenzitet parazitske infekcije sa S. papillosus. Kontrolnu grupu (n = 10) činile su ovce negativne na prisustvo parazitske infekcije. Stepen i vrsta promene praćeni su određivanjem koncentracije glukoze, ukupnih proteina, albumina, A/G ratio, AST, urea, ukupnog bilirubina, kalcijuma, fosfora, ukupne aktivnosti LDH i izoenzimske distribucije LDH1-5. Na osnovu dobijenih rezultata utvrdili smo, preko izoenzimske distribucije LDH, da u toku parazitske infekcije sa S. papillosus dolazi do oštećenja jetre, srčanog mišića i pluća, dok nakon terapije sa ABZ jetra je organ koji je najviše oštećen. Koncentracija glukoze, ukupnih proteina i albumina linearno je opadala sa rastom intenziteta parazitske infekcije (p LT 0.05), a nakon terapije sa ABZ pad koncentracije ovih parametara bio je na statistički značajnom većem nivou (p LT 0.01). Aktivnost AST, koncentracija uree i ukupnog bilirubina takođe su linearno rasle sa intenzitetom parazitske infekcije (p LT 0.05). Nakon terapije sa ABZ aktivnost AST i koncentracija ukupnog bilirubina bile su na statistički značajno većem nivou (p LT 0.001), dok je koncentracija uree zadržala iste nivoe kao u slučaju parazitske infekcije. Vrednosti koncentracija kalcijuma (p > 0.05) i fosfora (p LT 0.05) takođe linearno opadaju sa rastom intenziteta parazitske infekcije. Trend pada koncentracije ovih makroelemenata, nastavlja se i nakon terapije sa albendazolom (p LT 0.001). Imajući u vidu naša prethodna istraživanja na polju oksidativnog stresa, fenomena koji se nalazi u osnovi ovih promena, strogo preporučujemo da se u antiparazitske protokole, pored antihelmintika koriste i preparati sa antioksidativnim osobinama

Ergonomics problems in dental profession-dentists working position

Background/Aim: Dental professionals are under higher risk of development musculoskeletal disorders. Working in unnatural position is one of the main risk factor for the development of MSDs. The aim of study was to record inclinations of the back in dentists during typically dental work. Material and Methods: In order to monitor the inclination of the body, high-performance sensor systems, triaxial digital 12-bit accelerometers LIS3LV02 (SGS-Thomson Microelectronics, USA) were installed. The inclination of the body was measured in ten dentists, while performing dental work. Results: During dental work in a sitting position, sloping back more than 20 ̊ was during 74% of the time, while during standing 62% of the time. The participants performed the dental examination sloping to the left side. During sitting, the inclination to the left side was greater than 20 ̊ during 65% of the time, while during work in the standing position it was 50%. Conclusions: An inclination of the back, more than 20 degrees is state as one of the main risk factor for the development of MSD. Inclination of the dentist's body in antero-posterior and medio-lateral direction during daily work in standing as well in sitting position was greater than 20 degrees. According to those facts dentists are under risk of developing musculoskeletal diseases during their daily working procedure. According to that ergonomics in dentistry is an area of research that needs more attention. The implementation of ergonomic principles in usual dental work leads to increased work performance, greater satisfaction, efficiency and productivit

Oral squamous cell carcinoma detection by salivary biomarkers in a Serbian population

Early detection of oral squamous cell cancer (OSCC) is the key to improve the low 5-year survival rate. Using proteomic and genomic technologies we have previously discovered and validated salivary OSCC markers in American patients. The question arises whether these biomarkers are discriminatory in cohorts of different ethnic background. Six transcriptome (DUSP1, IL8, IL1B, OAZ1, SAT1, and S100P) and three proteome (IL1B, IL8, and M2BP) biomarkers were tested on 18 early and 17 late stage OSCC patients and 51 healthy controls with quantitative PCR and ELISA. Four transcriptome (IL8, IL1B, SAT1, and S100P) and all proteome biomarkers were significantly elevated (p lt 0.05) in OSCC patients. The combination of markers yielded an AUC of 0.86, 0.85 and 0.88 for OSCC total, T1-T2, and T3-T4, respectively. The sensitivity/specificity for OSCC total was 0.89/0.78, for T1-T2 0.67/0.96, and for T3-T4 0.82/0.84. In conclusion, seven of the nine salivary biomarkers (three proteins and four mRNAs) were validated and performed strongest in late stage cancer. Patient-based salivary diagnostics is a highly promising approach for OSCC detection. This study shows that previously discovered and validated salivary OSCC biomarkers are discriminatory and reproducible in a different ethnic cohort. These findings support the feasibility to implement multi-center, multi-ethnicity clinical trials towards the pivotal validation of salivary biomarkers for OSCC detection