• Childhood Kidney Diseases
• /
• v.9 no.2
• /
• pp.167-174
• /
• 2005

Purpose : Relapses are a major problem in children with steroid responsive nephrotic syndrome(SRNS). This study has been performed to determine the predictive factors for relapse in children with SRNS. Methods : The study group consisted of 7,3 children with SRNS who had been admitted to the Department of Pediatrics, Kyungpook National University Hospital, over 6 years from 1996 to 2001. The medical records were reviewed retrospectively and analyzed to determine significant relationships between selected variables[age at onset, sex, laboratory data, the rapidity of response(days to remission), interval to first relapse] and the frequency of relapse. Results : The age($mean{\pm}SD$) of patients was $4.53{\pm}2.53$ years old. The male to female ratio was 52:21. In 95$\%$, 39 out of the 41 children had a renal biopsy, and the final diagnosis was minimal change nephrotic syndrome. There was no significant correlation between the frequency of relapse and the following variables age at onset, sex, and presence of hematuria. However, the rapidity of response correlated well with the frequency of relapse, especially during the first year after the onset of the disease(P=0.005). Conclusion : The rapidity of response is expected to be one of the predictive (actors for relapse in children with SRNS. (J Korean Soc Pediatr Nephrol 2005;9:167-174)

• International Journal of Contents
• /
• v.4 no.3
• /
• pp.20-28
• /
• 2008

To obtain realistic performance measures for wireless networks, one should consider changes in performance due to failure related behavior. In performability analysis, simultaneous consideration is given to both pure performance and performance with failure measures. SRN is an extension of stochastic Petri nets and provides compact modeling facilities for system analysis. In this paper, a new methodology to model and analyze performability based on stochastic reward nets (SRN) is presented. Composite performance and availability SRN models for wireless handoff schemes are developed and then these models are decomposed hierarchically. The SRN models can yield measures of interest such as blocking and dropping probabilities. These measures are expressed in terms of the expected values of reward rate functions for SRNs. Numerical results show the accuracy of the hierarchical model. The key contribution of this paper constitutes the Petri nets modeling techniques instead of complicate numerical analysis of Markov chains and easy way of performance analysis for channel allocation under SRN reward concepts.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.05a
• /
• pp.636-638
• /
• 2010

Task scheduling is an integral part of parallel and distributed computing. Extensive research has been conducted in this area leading to significant theoretical and practical results. Stochastic reward nets (SRN) is an extension of stochastic Petri nets and provides compact modeling facilities for system analysis. In this paper, we address task scheduling model using extended timed marked graph, which is a special case of SRNs. And we analyze this model by giving reward measures in SRN.

• Childhood Kidney Diseases
• /
• v.25 no.2
• /
• pp.92-111
• /
• 2021

Purpose: Nephrotic syndrome (NS) is the most common form of glomerulopathy in children. Most pediatric patients respond to glucocorticosteroid treatment (steroid-sensitive NS, SSNS), while approximately 10-15% will remain unresponsive or later become steroid-resistant. There has been a long-standing effort to find biomarkers that may predict steroid responsiveness. Methods: We systematically reviewed current studies which investigated clinically relevant biomarkers for predicting steroid responsiveness in pediatric NS. We performed a PubMed and EMBASE search to identify eligible articles. We collected data on urinary markers, blood/serum markers (including cellular phenotypes and mRNA expression), genotypes and HLA allele frequency. Results: A total of 659 articles were identified following electronic and manual searches. After reviewing the titles, abstracts, and full texts, 72 eligible articles were finally included. Vitamin D-binding protein (VDBP) seemed to be significantly elevated in SRNS than in SSNS, in both serum and urine specimen, although further validation is required. Conclusions: The present paper narratively illustrates current understandings of potential biomarkers that may help predict steroid responsiveness. Further investigation and collaboration involving a larger number of patients are necessary.

• Journal of Digital Convergence
• /
• v.11 no.12
• /
• pp.479-485
• /
• 2013

Virtualization is a promising approach to consolidating multiple online services onto a smaller number of computing resources. A virtualized server environment allows computing resources to be shared among multiple performance isolated platforms called virtual machines. Through server virtualization software, applications servers are encapsulated into VMs, and deployed with APIs on top generalized pools of CPU and memory resources. Networking and security have been moved to a software abstraction layer that transformed computing, network virtualization. And it paves the way for enterprise to rapidly deploy networking and security for any application by creating the virtual network. Stochastic reward net (SRN) is an extension of stochastic Petri nets which provides compact modeling facilities for system analysis. In this paper, we develop SRN model of network virtualization based on virtual switch. Measures of interest such as switching delay and throughput are considered. These measures are expressed in terms of the expected values of reward rate functions for SRNs. Numerical results are obtained according to the virtual switch capacity and number of active VMs.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.7A
• /
• pp.951-958
• /
• 2000

In wavelength-routed all-optical networks, signals are transmitted on a direct optical path, or a lightpath, in a single-hop manner without opto-electronic/electro-optic(OE/EO) conversion at intermediate nodes. However, due to the physical constraints of optical elements such as ASE noise and crosstalk signals can be degraded un a long path. To establish a connection under such impairments, the optical signal may need to be regenerated at intermediate nodes, dividing a lightpath into two or more fragments. However, since signal regeneration at intermediate nodes requires additional network resources, the selection of these nodes should be made carefully to minimize blocking of other lightpaths. In this paper, we deal with the problem of establishing a lightpath in a multihop manner under physical constraints. We provide both minimal-cost and heuristic algorithms for locating signal regeneration nodes(SRNs). For a minimal-cost algorithm, we formulate the problem using dynamic programming(DP) such that blocking of other lightpaths due to the lack of transmitters/receivers(TXs/RXs) and wavelengths is minimized throughout the network.

• Clinical and Experimental Pediatrics
• /
• v.51 no.3
• /
• pp.293-298
• /
• 2008

Purpose : The aim of our study was to evaluate the therapeutic response to cyclosporine, time to remission and side effects in steroid resistant nephrotic syndrome (SRNS). Methods : This study included 22 children with idiopathic SRNS who were treated with cyclosporine between June 1989 and August 2006. Medical records were reviewed retrospectively. Results : The mean age of patients at diagnosis was $5.2{\pm}3.3\;years$. The male to female ratio was 1.2:1. Pre-treatment renal biopsies showed minimal change (MCD) in 12 (54.5%), focal segmental glomerulosclerosis (FSGS) in 8 (36.4%), membranous nephropathy (MGN) in one (4.5%) and mesangioproliferative glomerulonephritis in one (4.5%). 15 (68.2%) patients responded to cyclosporine, of whom 11 (91.6%) patients were MCD, 3 (37.5%) patients FSGS, and 1 patient MGN (MCD vs FSGS, P<0.05). The time to remission in patients who responded to cyclosporine was $31.5{\pm}15.2\;days$. Four of the 15 cyclosporine responders maintained complete remission even after cessation of the medication Seven still received cyclosporine, 2 were intermittently treated with steroids after discontinuation of cyclosporine, and two were treated with cyclosporine and steroids. The mean duration of cyclosporine therapy was $546.5{\pm}346.2$, $1,392.9{\pm}439.7$, $439.5{\pm}84.1$, and $433.5{\pm}74.2$ days, respectively. We performed post-treatment biopsies in 8 patients and partial interstitial fibrosis and tubular atrophy were found in two. Conclusion : The thrapeutic response of cyclosporine is good in steroid resistant nephrotic syndrome, especially in minimal change. But, there is a problem of long term cyclosporine dependency.