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This paper describes three phase bi-directional battery charger widely used in Energy storage application. The full bridge scheme is widely used for the high power application. The high-frequency transformer is used for the isolation purpose. This paper describes the design and simulation of a 7.75-kW, full-bridge, bi-directional isolated dc-dc converter with active front-end converter (AFC). The AFC is connected with the 3-phase ac system, which provides 650 to 700 dc voltage to dc-dc converter with lower value of THD (according to IEEE- 915) and improve power factor at input side. The dc-dc converter converts 310V from 650V for charging the battery. Software tool PSIM is used to obtain the simulation result of the converter. The closed loop system is simulated to achieved voltage and current ripple at output side less than 1% rms of rated voltage.

A major gap outspokenly voiced by leading scholars in the context of L2 testing concerns the lack of diagnostic tests that aim at surfacing learners’ underlying abilities (Alderson, 2005; Poehner, 2009). Dynamic assessment (henceforth DA) armed with the interaction tool which is construed as a pivotal mainstay of Vygotsky’s Socio-cultural Theory of Mind has been recently introduced to function as a robust diagnostic procedure to feed back into educational practices (Aljaafreh & Lantolf, 1994; Poehner, 2005; Ableeva, 2008). However, as for diagnostic assessment of L2 listening in the classroom, no worthwhile attempt has been made thus far (Buck, 2003; Vandergrift, 2006; Ableeva, 2010); hence, the need to undertake the present study. This paper has set out to explore the feasibility of group dynamic assessment (G-DA) in the classroom context as a diagnostic procedure to identify the intermediate L2 learners’ listening difficulties and the effects of G-DA on their listening development. In so doing, a group of intermediate L2 learners were recruited and instructed for a time span of two months. An interactionist, concurrent G-DA methodology guided the research design of this study. The results of qualitative analysis of G-DA protocols revealed that through continent, graduated and dialogic interactions with the learners in their Zone of Proximal Development G-DA can microgenetically uncover the learners’ sources of listening difficulties. The analysis brought to surface phonological, lexical and grammatical as the most rampant sources of difficulties during listening comprehension. The G-DA interactions also revealed how collective scaffolding (Donato, 1994) could help establish a state of intersubjectivity (Platt & Brooks, 1994) within the social space of the class during which secondary interactants benefited from the contributions of primary interactants (Poehner, 2009). Finally, on implication side, this paper recommends the use of G-DA methodology as an efficient and student/mediator-friendly procedure in the social microcosm of the classroom context to truly assess L2 learners’ listening comprehension processes and help promote the abilities which are in the state of maturation.

The investigation focuses on the effectiveness of fiber reinforced polymer (FRP) confinement in upgrading ductility and strength of concrete columns under axial compression. An experimental program is carried out to investigate the influence of the radius of the cross sectional corners on the strength of small scale square column specimens confined with FRP composite laminates. This study was achieved by testing 63 specimens depending on the selected corner radius, the section varied from square to circular. The various parameters such as corner radius, wrap thickness and fiber orientation of 0°, 90°, +45°,-45° and combinations of them were investigated. Smoothening of the edges of square cross-section plays a significant role in delaying the failure of FRP composite at these edges and the efficiency of FRP confinement is directly related to the radius of the cross-section edges.

The present study aimed to determine the influence of the compassionate mind based cognitive therapy on negative emotions and ruminations of women with depression who were referred to the treatment centers. Current study is an experimental pre-post test design with control group. The study population included all depressed women in Ardebil during 2011. Subjects consisted 34 depressed women which were selected by convinced method and divided randomly in two experimental and control groups. To collect data,we used Beck depression, self consciousness emotions scale , rumination scale and self compassionate scale. Compassionate mind based cognitive therapy was used as the intervention.The data was analyzed by multiple analyses of variance method (MANOVA). The results of analysis variance showed compassionate mind based cognitive therapy would significantly decreased shame, guilt, mind ruminations and depression signs in depressed women. By paying attention to the result of the present research, the implication of compassionate mind based cognitive therapy is recommended.

Designing cost-efficient, secure network protocols for Wireless Sensor Networks (WSNs) is a challenging problem because sensors are resource-limited wireless devices. Resource limited in the sense limited energy level, memory and computational capacity. Since the communication cost is the most dominant factor in a sensor’s energy consumption. We introduce an Energy-Efficient Energy Based Encryption and Keying with Collision Avoidance scheme for WSNs that significantly reduces the number of transmissions needed for rekeying. This is done to avoid stale keys. Energy based encryption is a secure communication framework where sensed data is encoded using a scheme based on a permutation code generated by using the RC4 encryption mechanism. Dynamic keys are used for the packets in the stream. The intermediate nodes in the path verify the authenticity and integrity of the incoming packets. The key generated by the sender’s virtual energy, this avoids the rekeying. Energy based encryption efficiently transfers data between the nodes that are added in the watched list. Energy based encryption reduces transmission overhead. Transmission overhead increases if the packet size and also while transferring control messages for rekeying. During data transmission, if more than one node transmits data to same destination at same time the data gets collided at the receiving side. Retransmission reduces the energy level of the sensor node. While data is transmitted by first node and the next node must wait in queue until the first node completes its transmission. This mechanism avoids data collision in the destination and also it results in energy savings of a node because there is no need to transfer the same data again and again to the same destination if data collision occurs during transmission.

Sediment management strategies are a key requirement in developing countries including Iran because of the limited resources available. These targeting however hampered by the lack of reliable information on catchment sediment sources. This paper reports the results of using a quantitative composite ?ngerprinting technique to estimate the relative importance of the primary potential sources within the Amrovan and Royan catchments in Semnan Province, Iran. Fifteen tracers were first selected for tracing and samples were analyzed in the laboratory for these parameters. Statistical methods were applied to the data including Nonparametric Kruskal-Wallis test and Discriminant Function Analysis (DFA). For the Amrovan catchment three parameters (N, Cr and Co) were found to be not significant in making the discrimination. The optimum fingerprint, comprising C, P, Kaolinite and K was able to distinguish correctly 100% of the source material samples. For the Royan catchment, all of the 15 properties were able to distinguish between the six source types and the optimum fingerprint provided by stepwise DFA (Chlorite, XFD, N and C) correctly classifies 92.9% of the source material samples. The mean contributions from each sediment source obtained by multivariate mixing model varied at two catchments. For the Amrovan catchment Upper Red Formation was the main sediment sources as this sediment source approximately supplied 36% of the reservoir sediment whereas the dominant sediment source For the Royan catchment was from Karaj formation that supplied 33% of the reservoir sediments. Results indicated that the source ?ngerprinting approach appears to work well in the study catchments and to generate reliable results.

The dependency of neutron self-shielding factor on neutron field and sample size in large sample neutron activation analysis was experimentally assessed for powdered leaves samples up to 5 g in mass. The measurements of the neutron flux depression inside the samples were used in determining the neutron self-shielding factor. The experimental results agreed with the theoretical estimation that neutron self-shielding factor is dependent on neutron flux level and sample size. Neutron self-shielding was found to increase with decreasing neutron flux level and increasing sample size and vice versa.

In this paper, we propose an integrated face recognition system that is robust against facial expressions by combining information from the computed intra-person optical flow and the synthesized face image in a probabilistic framework. Making recognition more reliable under uncontrolled lighting conditions is one of the most important challenges for practical face recognition systems. We tackle this by combining the strengths of robust illumination normalization. Our experimental results show that the proposed system improves the accuracy of face recognition from expressional face images and lighting variations.

Floristic studies are fundamental for the applied sciences such as rangeland management and conservation. Unique ecological and climatic conditions in the Tang Soulak Protected Area make it a remarkable habitat for the floristic studies. The purpose of this study was to determine floristic composition and their chorology carrying a central importance in vegetation description and analysis. Therefore, 50 quadrats (100 m2) were located according to the nature of vegetation. The species and their abundance-dominance were recorded. 70 plant species, belonging to 21 families, were identified. Plant classification, based on Raunkiaer’s life forms revealed Hemicryptophytes as the most abundant (46% of total) species. Therophytes, Phanerophytes and Chamaephytes contained 26, 12 and 4 percents of total plant species, respectively. Chorological characteristics of the plant species showed, about 66% of the total plant species in Tang Soulak area were belonged to the Irano-Turanian Chorotype.

An elderly lady came to our gynaecology clinic with foul smelling vaginal discharge since 2 years. It was a case of retained foreign body in vagina for 6 years, a wood apple was inserted to reduce uterine prolapsed. The is rare presentation now a days.