Boost Integrated Three-Phase Solar Inverter using Current Unfolding and Active Damping Methods

© 2018 IEEJ Industry Application Society. This paper proposes a three-phase grid connected solar inverter with integrated boost function. The circuit operating principle is based on current unfolding and injection method, which is similar to that of a SWISS rectifier. This approach requires only two high frequency switches operating at only half voltage stress, thus leading to a significant reduction in switching losses. Other switches only operate at line frequency, and therefore can be optimized to reduce conduction losses. The proposed inverter therefore can deliver high efficiency. This paper discusses the basic operating principle as well as control method for the inverter. It is revealed that the output currents of the proposed inverter contains intrinsic oscillation due to current unfolding operation. In order to solve this problem, an active damping method is proposed to stabilize the operation. As a result, stable operation of the proposed method is confirmed by simulation. The feasibility of the proposed inverter is also confirmed using a mini laboratory prototype

Identifying QTLs Associated and Marker-Assisted Selection for Salinity Tolerance at the Seedling, Vegetative and Reproductive Stages in Rice (Oryza Sativa L.)

Salinity affects rice growth in all growth stages, with the seedling and reproductive stages being the most sensitive. Genetically improving salt tolerance of rice is an important objective of rice breeding programs. Hence, mapping quantitative trait loci (QTL) will be useful for marker-assisted selection in rice breeding programs. An advanced backcross population (BC2F2) was developed with the parents included OM5629 as a donor of salt tolerance and OM7347 as a recurrent parent with good quality traits and drought tolerance. Molecular markers associated with both qualitative and quantitative trait loci (QTL) salt tolerance were identified by using 416 polymorphic SSR markers. QTLs, associated with stress tolerance at EC = 15 dS/m at seedling stage, detected from the BC2F2 population of OM7347/OM5629, were located on chromosomes 1 and 3. Three QTLs were identified at the intervals of RM3252-S1-1 - RM10694, RM3740-RM5336 and RM11125-RM9 with genetic distance of 4.4, 4.5 and 18 cM on chromosome 1, respectively. Two QTLs at the intervals of RM3867-RM6959 and RM6876-RM4425 with genetic distance of 4.5 and 18.0 cM on chromosome 3, respectively. One QTL on chromosome 5 was detected at the interval of RM874 - RM10359, it was associated with salt stress tolerance under EC = 8dS/m at vegetative stage. Three QTLs at the regions of RM1324-RM2412, RM1185-RM24, and RM1282-RM2560 on chromosome 1, and one QTL of RM453-RM511 on chromosome 12, were related to salt tolerance under EC = 8dS/m at reproductive stage. Two tightly linked markers as RM3252-S1-1 and RM3867, were exhibited their effectiveness in identification of salt tolerance genotypes in BC3F6 population of OMCS2000/ Pokkali. The identification of new QTLs associated with salt tolerance will provide important information for the functional analysis of rice salinity stress

Pharmacist-Led Intervention to Enhance Medication Adherence in Patients With Acute Coronary Syndrome in Vietnam:A Randomized Controlled Trial

Background: Patient adherence to cardioprotective medications improves outcomes of acute coronary syndrome (ACS), but few adherence-enhancing interventions have been tested in low-income and middle-income countries. Objectives: We aimed to assess whether a pharmacist-led intervention enhances medication adherence in patients with ACS and reduces mortality and hospital readmission. Methods: We conducted a randomized controlled trial in Vietnam. Patients with ACS were recruited, randomized to the intervention or usual care prior to discharge, and followed 3 months after discharge. Intervention patients received educational and behavioral interventions by a pharmacist. Primary outcome was the proportion of adherent patients 1 month after discharge. Adherence was a combined measure of self-reported adherence (the 8-item Morisky Medication Adherence Scale) and obtaining repeat prescriptions on time. Secondary outcomes were (1) the proportion of patients adherent to medication; (2) rates of mortality and hospital readmission; and (3) change in quality of life from baseline assessed with the European Quality of Life Questionnaire - 5 Dimensions - 3 Levels at 3 months after discharge. Logistic regression was used to analyze data. Registration: ClinicalTrials.gov (NCT02787941). Results: Overall, 166 patients (87 control, 79 intervention) were included (mean age 61.2 years, 73% male). In the analysis excluding patients from the intervention group who did not receive the intervention and excluding all patients who withdrew, were lost to follow-up, died or were readmitted to hospital, a greater proportion of patients were adherent in the intervention compared with the control at 1 month (90.0% vs. 76.5%; adjusted OR = 2.77; 95% CI, 1.01-7.62) and at 3 months after discharge (90.2% vs. 77.0%; adjusted OR = 3.68; 95% CI, 1.14-11.88). There was no significant difference in median change of EQ-5D-3L index values between intervention and control [0.000 (0.000; 0.275) vs. 0.234 (0.000; 0.379); p = 0.081]. Rates of mortality, readmission, or both were 0.8, 10.3, or 11.1%, respectively; with no significant differences between the 2 groups. Conclusion: Pharmacist-led interventions increased patient adherence to medication regimens by over 13% in the first 3 months after ACS hospital discharge, but not quality of life, mortality and readmission. These results are promising but should be tested in other settings prior to broader dissemination

Phenotypic Screening of Drought-Tolerant Lines for Brown Planthopper, Blast and Phytic Acid Content Assay of Rice (Oryza sativa L.)

Advanced drought tolerant lines were analysed for blast disease, brown planthopper (BPH), and phytic acid content. Thirsty lines of BC2F4 derived from OMCS2000/ IR75499-73-1 were used to screen for BPH and blast resistance. Three good resistant lines were screened against blast (45, 54, and 310) under greenhouse condition. As eight lines were identified to be resistant to BPH. The results further reveal that BC2F4-45 was the best line resistant to both BPH and blast disease. These lines will be useful in reducing grain phytic acid and improving the nutritional value of rice grain. Based on an assay for high phosphate germination stage of rice, the lowest content was found in the I5 variety (line 45). Hence, this line provides the urgent objective for breeders in cultivars of these crops to genetically enhance a healthy and functional diet. These characters will then need to be incorporated into high yield under drought stress with others such as disease and insect resistance

BIOLOGICAL AMMONIA REMOVAL BY SUBMERGED AERATED FILTER FROM HANOI GROUND WATER

Joint Research on Environmental Science and Technology for the Eart

Low dietary intakes of essential nutrients during pregnancy in Vietnam

Inadequate intake of nutrients during pregnancy has been associated with poor pregnancy and infant outcomes; however, evidence remains limited in low-resource settings in Asia. This paper assessed food, macronutrient, and micronutrient intakes among 1944 Vietnamese pregnant women. Dietary information was collected via an interviewer-administered food frequency questionnaire, and nutrient intakes were estimated using the Vietnamese food composition tables. The levels of nutrient intakes were evaluated against the Vietnamese recommended nutrient intakes (RNI) for pregnancy. The diet profiles were reported as means and percentages. The average daily food intakes across socio-demographic factors were compared using ANOVA, with adjustment for multiple comparisons by the Tukey–Kramer test. Rice, fruits, and vegetables were the main food sources consumed. The mean energy intake was 2004 kcal/day with 15.9%, 31.8%, and 52.2% of energy deriving from proteins, fats, and carbohydrates, respectively. Just over half of the women did not meet the RNI for total energy intake. The intakes of essential micronutrients including folate, calcium, iron, and zinc were below the RNI, and almost all pregnant women failed to meet the recommendations for these micronutrients. The associations of maternal age, education, and pre-pregnancy body mass index with nutrient intakes varied across the nutrient subgroups. Targeted programs are needed to improve nutrient intakes in Vietnamese pregnant women

Dynamical Properties of the 1/r^2-Type Supersymmetric t-J Model in a Magnetic Field: Manifestation of Spin-Charge Separation

Quasi-particle picture in a magnetic field is pursued for dynamical spin and charge correlation functions of the one-dimensional supersymmetric t-J model with inverse-square interaction. With use of exact diagonalization and the asymptotic Bethe-ansatz equations for finite systems, excitation contents of relevant excited states are identified which are valid in the thermodynamic limit. The excitation contents are composed of spinons, antispinons, holons and antiholons obeying fractional statistics. Both longitudinal and transverse components of the dynamical spin structure factor are independent of the electron density in the region where only quasi-particles with spin degrees of freedom (spinons and antispinons) contribute. The dynamical charge structure factor does not depend on the spin-polarization density in the region where only quasi-particles with charge (holons and antiholons) are excited. These features indicate the strong spin-charge separation in dynamics, reflecting the high symmetry of the model.Comment: 10 pages, 1 table (PS file), 15 figures (JPEG file). Submitted to J. Phys. Soc. Jp

Security-reliability analysis in CR-NOMA IoT network under I/Q imbalance

This paper presents a controllable analysis framework for evaluating the reliability and security of underlay cognitive radio networks (CRs) relying on non-orthogonal multiple access (NOMA). In such systems, a secondary base station (BS) transmits confidential information to multiple secondary users uniformly distributed in the presence of a nearby located external eavesdropper. Moreover, transmit power constraints are introduced to limit the interference to the primary imposed by cognitive base stations. As an effective approach of multiple input single output (MISO) systems, the transmit antenna selection (TAS) is selected in the BS to improve the secrecy performance of the primary networks. Furthermore, we first consider the impact of quadrature-phase imbalance (IQI) to characterize the secure performance of the considered network in practice. Then, the degraded performance is evaluated in terms of outage probability (OP), intercept probability (IP), and effective secrecy throughput (EST) of two NOMA users. The optimal EST can be achieved through simulations while the results of OP and IP provide guidelines in the design of IQI-aware CR-NOMA systems. Finally, the trade-off between OP and IP with transmit signal-to-noise ratio (SNR) at the BS is investigated for reflecting the security characteristic. Finally, the trade-off between OP and IP with transmit signal-to-noise ratio (SNR) at the BS is studied for displaying the security characteristic. Numerical results show that increasing the number of transmit antennas at the BS and other main parameters improves performance. Moreover, when the system parameters are reasonably set, the secondary NOMA user in CR-NOMA can be reached secure requirements regardless of the controlled IQI.Web of Science1111905611904

A prospective multi-center observational study of children hospitalized with diarrhea in Ho Chi Minh City, Vietnam.

We performed a prospective multicenter study to address the lack of data on the etiology, clinical and demographic features of hospitalized pediatric diarrhea in Ho Chi Minh City (HCMC), Vietnam. Over 2,000 (1,419 symptomatic and 609 non-diarrheal control) children were enrolled in three hospitals over a 1-year period in 2009-2010. Aiming to detect a panel of pathogens, we identified a known diarrheal pathogen in stool samples from 1,067/1,419 (75.2%) children with diarrhea and from 81/609 (13.3%) children without diarrhea. Rotavirus predominated in the symptomatic children (664/1,419; 46.8%), followed by norovirus (293/1,419; 20.6%). The bacterial pathogens Salmonella, Campylobacter, and Shigella were cumulatively isolated from 204/1,419 (14.4%) diarrheal children and exhibited extensive antimicrobial resistance, most notably to fluoroquinolones and third-generation cephalosporins. We suggest renewed efforts in generation and implementation of policies to control the sale and prescription of antimicrobials to curb bacterial resistance and advise consideration of a subsidized rotavirus vaccination policy to limit the morbidity due to diarrheal disease in Vietnam