This paper presents a new method regarding fault distribution modeling for the stochastic prediction study of voltage sags in the distribution system. 2-D stochastic models for fault modeling make it possible to obtain the fault performance for the whole system of interest, which helps to obtain not only sag performance at individual locations but also system sag performance through system indices of voltage sag. By using the bivariate normal distribution for fault distribution modeling, this paper estimates the influence of model parameters on system voltage sag performance.The paper also develops the modified SARFI X regarding phase loads that create better estimation for voltage sag performance for the distribution system.Index Terms-Bivariate normal distribution, distribution system, fault distribution modeling, phase loads, power quality (PQ), stochastic prediction, voltage sag frequency.

No abstract

The frequencies and diversities of human leukocyte antigen (HLA) alleles and haplotypes are representative of ethnicities. Matching HLA alleles is essential for many clinical applications, including blood transfusion, stem cell transplantation, and tissue/organ transplantation. To date, the information about the frequencies and distributions of HLA alleles and haplotypes among the Kinh Vietnamese population is limited because of the small sample size. In this study, more than 3,750 cord blood units from individuals belonging to the Kinh Vietnamese population were genotyped using PCR sequence-specific oligonucleotide (PCR-SSO) for HLA testing. The results of the study demonstrated that the most frequently occurring HLA-A, -B, -C, and -DRB1 alleles were A*11:01 (25%), A*24:02 (12.3%), A*02:01 (11.2); A*03:03 (8.95%), A*02:03 (7.81%), A*29:01 (7.03%); B*15:02 (15.1%), B*46:01 (10.7%), B*58:01 (7.65%), B*38:02 (7.29%); C*08:01 (17.2), C*07:02 (16.2%), C*01:02 (15.2), C*03:02 (8.3%), C*15:05 (6.13); DRB1*12:02 (31.0%), DRB1*09:01 (10.47%), DRB1*15:02 (7.54%); DRB1*07:01 (6.68%), DRB1*10:01 (6.63%), respectively, with the highest allele diversity level observed in locus B (93 alleles). The most frequent haplotypes of two-locus combinations of HLA-A–B, HLA-A–C, HLA-A–DRB1, HLA-B–C, HLA-B–DRB1, and HLA-C–DRB1 haplotypes were A*11:01–B*15:02 (7.63%), A*11:01–C*08:01 (7.98%), A*11:01–DRB1*12:02 (10.56%), B*15:02–C*08:01 (14.0%), B*15:02–DRB1*12:02 (10.47%), and C*08:01–DRB1*12:02 (11.38%), respectively. In addition, the most frequent haplotypes of three- and four-locus sets of HLA-A–B–C, HLA-A–B–DRB1, HLA-A–C–DRB1, HLA-B–C–DRB1, and HLA-A–B–C–DRB1 were A*11:01–B*15:02–C*08:01 (7.57%), A*11:01–B*15:02–DRB1*12:02 (5.39%), A*11:01–C*08:01–DRB1*12:02 (5.54%), B*15:02–C*08:01–DRB1*12:02 (10.21%), and A*11:01–B*15:02–C*08:01–DRB1*12:02 (5.45%), respectively. This study provides critical information on the frequencies and distributions of HLA alleles and haplotypes in the Kinh Vietnamese population, accounting for more than 85% of Vietnamese citizens. It paves the way to establish an umbilical cord blood bank for cord blood transplantation programs in Vietnam.

This paper presents a novel proposal for quantifying the influence of Demand Side Management (DSM) objectives on electric energy loss in distribution system. DSM objectives are modeled by VPI model and the testing results prove its suitability, especially for analysis on energy loss in distribution system. This paper uses IEEE's 34 Node Test Feeder as the test system for energy loss calculation and the analysis of DSM's influences. Network modeling is made using PSS/ADEPT 5.0. The research uses typical daily load curves of industrial and residential loads in Vietnam as a case study. Results not only indicate the effectiveness of loss reduction in DSM peak-clipping and load shifting, but also recommend DSM strategies for the best effect on energy loss reduction basing on modeling error testing.

In this paper, a novel effort for prediction of voltage sag in the entire transmission system of Vietnam is presented. As the Vietnamese electricity industry moves toward the electricity market, prediction will help utilities have early assessment of power quality in transmission system. The proposed prediction approach uses a fault position method in which the fault distribution in the transmission system is created based on an actual fault occurrence in the entire 220kV and 500kV transmission system throughout Vietnam that took place in 2008. The research also makes use of the SARFI CURVE with ITIC and SEMI curve, which takes into account of the actual fault clearing time of protective devices used in transmission system in Vietnam. By using SARFI CURVE , a better assessment of voltage sag performance is obtained in the transmission system with regard to load's voltage tolerance.