• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.31 no.7A
• /
• pp.649-658
• /
• 2006

Recently, Software Development was applied to new-approach methods as a various form : client-server system and web-programing, object-orient concept, distributed development with a network environments. On the other hand, it be concerned about the distributed development technology and increasing of object-oriented methodology. These technology is spread out the software quality and improve of software production, reduction of the software develop working. Futures, we considered about the distributed software development technique with a many workstation. In this paper, we discussed optimal release problem based on a stochastic differential equation model for the distributed Software development environments. In the past, the software reliability applied to quality a rough guess with a software development process and approach by the estimation of reliability for a test progress. But, in this paper, we decided to optimal release times two method: first, SRGM with an error counting model in fault detection phase by NHPP. Second, fault detection is change of continuous random variable by SDE(stochastic differential equation). Here, we decide to optimal release time as a minimum cost form the detected failure data and debugging fault data during the system test phase and operational phase. Especially, we discussed to limitation of reliability considering of total software cost probability distribution.

• Journal of the Society of Disaster Information
• /
• v.17 no.3
• /
• pp.617-626
• /
• 2021

Purpose: The purpose of this study is to evaluate the fire srpead risk of building exterior and roofing materials due to the firebrand of forest fire occurring in the urban areas. Method: In order to achieve this research purpose, by selecting building materials used for exterior and roofing materials of buildings, the time to ignition, total heat release, and heat release rate were investigated, and a forest fire firebrand system was established to the possibility of fire spread was confirmed. Result: As a result of the cone calorimeter test, the roofing material had a similar or faster ignition time due to radiant heat compared to the exterior material with the steel plate exposed to the outside, and showed a higher heat release rate and total heat release than the exterior material. Although it was affected by the flammable material, it was confirmed that it did not spread easily due to the limited amount of combustible material, and carbonization marks appeared inside. Conclusion: The cone calorimeter test method has been shown to be useful in understanding the combustion characteristics of building materials by radiant heat, but the fire spread due to a firebrand in a forest fire is directly affected by the flame due to the ignition of surrounding combustibles, so finding a direct correlation with the cone calorimeter method is difficult. It is judged that the roof material may be more vulnerable to the spread of fire due to the fire than the exterior material.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.1
• /
• pp.125-129
• /
• 2016

Background: Patients with differentiated thyroid cancers (DTC) who receive radioactive iodine-131 (RAI) are released from isolation when their dose rate is below the regulatory requirements. The purpose of this study was establish predicting factors for early release from the isolation facility after RAI administration in patients with DTC. Materials and Methods: This was a prospective study which included 96 (58 females and 38 males) patients with DTC who had received RAI from April 2013 till August 2015. The study was duly approved by the ethical committee of the institute. Patients who had complete information of primary tumor size (PTS), serum TSH, stimulated thyroglobulin level [sTg] with antibodies (IU/ml) at the time of RAI treatment were included. All had a normal serum creatinine level. To attain lower effective half-life good hydration and administration of soft laxative were ensured. Dose rate was measured (immediately, 24 h and 36 h) at 1 meter distance from anterior mid trunk and a dose rate <$50{\mu}Sv/h$ was considered as the releasing criterion. At 24 h 50 patients were released while the remaining 46 patients were released at 36 h. A post-ablative whole body scan (PA-WBIS) was performed 5-8 days after RAI ablation in all patients. Results: Patients released after 24 h were significantly younger, had smaller lesions with higher proportion of papillary cancer, lower sTg, lower sTg/TSH ratio and had received a lower dose of RAI as comapred to those who were discharged after 36 h. Serum TSH and gender were not found to have any significant correlation between two cohorts. ROC and multivariate analysis have shown age ${\leq}37years$, PTS ${\leq}3.8cm$, $RAI{\leq}150mCi$, $sTg{\leq}145ng/ml$ and $sTg/TSH{\leq}1.085$ as strong indepedent predictors for early release. Conclusions: We conclude that younger age (${\leq}37years$), smaller tumor size (${\leq}3.8cm$), lower RAI dose (${\leq}150mCi$), lower sTg (${\leq}145ng/ml$) and a lower sTg/TSH ratio (${\leq}1.085$) are significant independent predictors for release at 24 h after RAI treatment in DTC patients. Effective utilization of these factors could help the treating physicians to use limited number of internment facilities with higher throughput, lower cost and lower psychological stress to patients.

• The KIPS Transactions:PartD
• /
• v.15D no.6
• /
• pp.841-856
• /
• 2008

The priority of requirement is important because the priority is a critical activity of release plan especially in software development which has an open market customer. Also, it is important for stakeholders to select a method and aspects to prioritize requirements. The selection is based on the organizational experience of a priority process, the process model of the product, goals and a type of products, and dependencies between requirements. But, the current researches considered only static dependency between requirements and did not suggest a systematic priority process. In addition, the current researches only suggest limited aspects to prioritize requirements, such as cost and value. Therefore, this paper proposes an adjustable priority process based on a priority model to select a method and aspects for the suitable priority for product and organization. Especially, this paper enhances the completeness of a release plan by a definition of static and dynamic dependency types between requirements. This paper suggests a priority model, which considers the dependencies between requirement and various viewpoint of software development. Based on the priority model, the paper suggests a systematic priority process to promote reasonable decisions to the priority and release plan of requirement.

• Journal of the Korean Institute of Gas
• /
• v.12 no.2
• /
• pp.38-41
• /
• 2008

In this research, we propose a new method for tracking the release rate using the concentration data obtained from the sensor. We used a sensor network that has already been set surrounding the area where hazardous gas releases can occur. From the real-time sensor data, we detected and analyzed releases of harmful materials and their concentrations. Based on the results, the release rate is estimated using the neural network. This model consists of 14 input variables (sensor data, material properties, process information, meteorological conditions) and one output (release rate). The dispersion model then performs the simulation of the expected dispersion consequence by combining the sensor data, GIS data and the diagnostic result of the source term. The result of this study will improve the safety-concerns of residents living next to storage facilities containing hazardous materials by providing the enhanced emergency response plan and monitoring system for toxic gas releases.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38A no.5
• /
• pp.401-408
• /
• 2013

Dual-layer differential codebook using 8-PSK (phase shift keying) constellation as its codeword elements, is proposed for Long term evolution (LTE) and/or LTE-Advanced systems. Due to the temporal correlation of the adjacent channel matrices, the consecutive precoding matrices are likely to be similar. This approach quantize only the differential information of the channel instead of the whole channel subspace, which virtually increase the codebook size to realize more accurate quantization of the channel. Especially, the proposed codebook has the same properties of LTE release-8 codebook that is, constant modulus, complexity reduction, and nested property. The mobile station can be designed by using less expensive non-linear amplifier utilizing constant modulus property. Computer simulations show that the capacity of the proposed dual-layer codebook performs almost 1.2dB better than those of any other non-differential codebooks with the same amount of feedback information.

• Journal of Digital Convergence
• /
• v.18 no.8
• /
• pp.179-184
• /
• 2020

This study aims to investigate the effect that local government's information release range on Covid-19 patients' contact trace on consumer sentiment in the region. One hundred twenty-eight residents of Gangnam-gu and Seocho-gu participated in the study. The results showed that when ambiguity of information increased perceived anxiety on Covid-19 patients' contact trace, which in turn led lower intention to visit the commercial district near the Covid-19 patients' contact trace. Based on the findings, several suggestions was proposed for future research, including longitudinal studies covering even the "long-term" changes in consumer sentiment, the effect of implicit anxiety, and the behavioral difference between residence and non-residence.

• Journal of the Society of Disaster Information
• /
• v.4 no.2
• /
• pp.124-136
• /
• 2008

The systematic information management of chemical accidents has been required as a tool for the policy making, system improvement and release of information concerning accident prevention. However, there is not yet a systematic chemical accidents tracking system in Korea, which make confusion among the related government agencies and the parties to accidents that the related statistics are different from each others. In this study, We developed the Chemical Accident Tracking System (CATS) using chemical accident classification which was made up of 12 upper classes, 70 middle classes, 272 lower classes. The CATS is mainly consist list up module, reporting module, searching and statistic module, etc. The CATS is expected to be applied to the information tracking and database system for chemical accidents and improve its manageability.

• Journal of the Korea Safety Management & Science
• /
• v.10 no.1
• /
• pp.49-58
• /
• 2008

The systematic information management of chemical accidents is required as a tool for the policy making, system improvement and release of information. However, there isn't yet a systematic chemical accidents tracking system in Korea, which make a confusion that the related statistics are different from each others. In this research, we analyzed domestic and international chemical accidents data and made the chemical accident codes for the information tracking system properly.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.7 no.1
• /
• pp.16-26
• /
• 1997

China is one of the few countries where natural disaster strike frequently and cause heavy damage. In this paper, we mathematically develop two models to assess fuzzy risk of natural disaster in China. One is to assess the risk based on database of historical disaster effects by using information diffusion method relevant in fuzzy information analysis. In another model, we give an overview over advanced method to calculate the risk of release, exposure and consequence assessent, where information distribution technique is used to calculate basic fuzzy relationships showing historical experience of natural disasters, and fuzzy approximate inference is employed to study loss risk based on these basic relationships. We also present an examples to show how to use the first model. Result show that the model is effective for natural disaster risk assessment.