• Fire Science and Engineering
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• v.34 no.3
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• pp.18-27
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• 2020

An actual fire test was performed on single combustibles placed in a local cinema complex, and quantitative differences in the maximum heat release rate (HRR) and fire growth rate were investigated based on the design fire curve methods (i.e., the general and 2-stage methods). In terms of combustible use and fire load, a total of 12 combustibles were selected, classified into cinema lounge and movie theater. It was found that the maximum HRR and fire growth rate determined using the two-stage method were quantitatively different from those of the general method. The application of the two-stage method, which can be used to determine the fire growth rate of the initial fire stage more precisely, could be useful in accurately predicting the activation time of fire detectors and fire-extinguishing facilities, as well as the available safe egress time (ASET) and required safe egress time (RSET).

• Journal of Gastric Cancer
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• v.12 no.3
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• pp.173-178
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• 2012

Purpose: To report the initial clinical experience with single-incision laparoscopic gastric wedge resection for submucosal tumors. Materials and Methods: The medical records of 10 patients who underwent single-incision laparoscopic gastric wedge resection between July 2009 and March 2011 were reviewed retrospectively. The demographic data, clinicopathologic and surgical outcomes were assessed. Results: The mean tumor size was 2.5 cm (range, 1.2~5.0 cm), and the tumors were mostly located on the anterior wall (4/10) or along the greater curvature (4/10), of the stomach. Nine of ten procedures were performed successfully, without the use of additional trocars, or conversion to laparotomy. One patient underwent conversion to multiport laparoscopic surgery, to get simultaneous cholecystectomy safely. The mean operating time was 66.5 minutes (range, 24~132 minutes), and the mean postoperative hospital stay was 5 days (range, 4~7 days). No serious perioperative complications were observed. Of the 10 submucosal tumors, the final pathologic report revealed 5 gastrointestinal stromal tumors, 4 schwannomas, and 1 heterotopic pancreas. Conclusions: Single-incision laparoscopic gastric wedge resection for gastric submucosal tumors is feasible and safe, when performed by experienced laparoscopic surgeons. This technique provides favorable cosmetic results, and also short hospital stay and low morbidity, in carefully selected candidates.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.2
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• pp.162-172
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• 2011

In this paper, simulation was used to determine accuracies of genomic breeding values for polygenic traits associated with many thousands of markers obtained from high density genome scans. The statistical approach was based upon stochastically simulating a pedigree with a specified base population and a specified set of population parameters including the effective and noneffective marker distances and generation time. For this population, marker and quantitative trait locus (QTL) genotypes were generated using either a single linkage group or multiple linkage group model. Single nucleotide polymorphism (SNP) was simulated for an entire bovine genome (except for the sex chromosome, n = 29) including linkage and recombination. Individuals drawn from the simulated population with specified marker and QTL genotypes were randomly mated to establish appropriate levels of linkage disequilibrium for ten generations. Phenotype and genomic SNP data sets were obtained from individuals starting after two generations. Genetic prediction was accomplished by statistically modeling the genomic relationship matrix and standard BLUP methods. The effect of the number of linkage groups was also investigated to determine its influence on the accuracy of breeding values for genomic selection. When using high density scan data (0.08 cM marker distance), accuracies of breeding values on juveniles were obtained of 0.60 and 0.82, for a low heritable trait (0.10) and high heritable trait (0.50), respectively, in the single linkage group model. Estimates of 0.38 and 0.60 were obtained for the same cases in the multiple linkage group models. Unexpectedly, use of BLUP regression methods across many chromosomes was found to give rise to reduced accuracy in breeding value determination. The reasons for this remain a target for further research, but the role of Mendelian sampling may play a fundamental role in producing this effect.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.521-529
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• 2002

The purpose of this study was to compare the shaping time of two shaping methods and the leakage of three different obturation techniques. Ninty three canaled human molar teeth were used, which were randomly divided into two groups of forty teeth each and ten control teeth. After working length determination, the one group was prepared crown-down technique using rotary root canal instruments of GT rotary files .12/20, .10/20, .08/20 and .06/20 taper(Maillefer Instrument SA. Switzerland). The other group was instrumented with Gates Glidden burs(#1, #2, and #3) to coronal preparation and GT rotary files .08/20 and .06/30 taper to apical preparation. Shaping time was measured. After root canals were instrumented, they were divided to three subgroups and obturated as follows : Subgroup 1, obturated with single cone method Subgroup 2, obturated with lateral condensation : Subgroup 3, obturated with continuous wave technique. Three subgroups were obturated using non-standardized gutta-percha cone(Diadent, Korea, .06 or .08 taper) and AH-26(Dentsply DeTrey, Germany) as a root canal cement. Ten unobturated teeth served as positive and negative controls. After immersion in 2% methylene blue solution for 1 month, the teeth were washed during 24h. The teeth were demineralized in 10% nitric acid and dehydrated by immersion in 80, 90 and 100% ethyl alcohol. The teeth were finally cleared and stored in 100% methylsalicylate, and apical dye penetration was evaluated under stereomicroscope(Leica M420, LC, U.S.A)at $\times$8.75 magnification. Liner measurement of dye penetration was assessed with the use of digitalized image analysing system (analySIS, GmbH, Germany) The data were analysed statistically using independent T-test and Two-way ANOVA and Tukey test. The result were as follows 1. In canal prepared with GT$^{TM}$ rotary file, shaphing time taked more than the group of using Gates Glidden drill to coronal preparation without statistical significance (p>0.05) 2. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files showed significantly more apical leakage than those of lateral condensation and continuous wave technique regardless of shaping method (p<0.05). 3 The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed significantly more apical leakage than those of continuous wave technique regardless of shaping method (p<0.05). 4. Regardless of shaping method, The group of continuous wave obturation showed less apical leakage than those of lateral condensation without statistical significance (p>0.05). 5. The group of single cone obturation using canal preparation of GT$^{TM}$ rotary files and Gates Glidden drill showed more apical leakage than the group of lateral condensation using same shaping method with-out statistical significance (p＞0.05).

• Microbiology and Biotechnology Letters
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• v.45 no.4
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• pp.358-364
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• 2017

Asymmetric PCR preferentially amplifies one DNA strand for use in DNA hybridization studies. Linear-After-The-Exponential-PCR (LATE-PCR) is an advanced asymmetric PCR method which uses innovatively designed primers at different concentrations. This study aimed to optimise LATE-PCR parameters to produce single-stranded DNA of Candida spp. and Aspergillus spp. for detection via probe hybridisation. The internal transcribed spacer (ITS) region was used to design limiting primer and excess primer for LATE-PCR. Primer annealing and melting temperature, difference of melting temperature between limiting and excess primer and concentration of primers were optimized. In order to confirm the presence of single-stranded DNA, the LATE-PCR product was hybridised with digoxigenin labeled complementary oligonucleotide probe specific for each fungal genus and detected using anti-digoxigenin antibody by dot blotting. Important parameters that determine the production of single-stranded DNA in a LATE-PCR reaction are difference of melting temperature between the limiting and excess primer of at least $5^{\circ}C$ and primer concentration ratio of excess primer to limiting primer at 20:1. LATE-PCR products of Candida albicans, Candida parapsilosis, Candida tropicalis and Aspergillus terreus at up to 1:100 dilution and after 1 h hybridization time, successfully hybridised to respective oligonucleotide probes with no cross reactivity observed between each fungal genus probe and non-target products. For Aspergillus fumigatus, LATE-PCR products were detected at 1:10 dilution and after overnight hybridisation. These results indicate high detection sensitivity for single-stranded DNA produced by LATE-PCR. In conclusion, this advancement of PCR may be utilised to detect fungal pathogens which can aid the diagnosis of invasive fungal disease.

• Journal of Mechanical Science and Technology
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• v.19 no.9
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• pp.1695-1705
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• 2005

Reaction wheels and thrusters are commonly used for the satellite attitude control. Since satellites frequently need fast maneuvers, the minimum time maneuvers have been extensively studied. When the speed of attitude maneuver is restricted due to the wheel torque capacity of low level, the combinational use of wheel and thruster is considered. In this paper, minimum time optimal control performances with reaction wheels and thrusters are studied. We first identify the features of the maneuvers of the satellite with reaction wheels only. It is shown that the time-optimal maneuver for the satellite with four reaction wheels in a pyramid configuration occurs on the fashion of single axis rotation. Pseudo control logic for reaction wheels is successfully adopted for smooth and chattering-free time-optimal maneuvers. Secondly, two different thrusting logics for satellite time-optimal attitude maneuver are compared with each other: constant time-sharing thrusting logic and varying time-sharing thrusting logic. The newly suggested varying time-sharing thrusting logic is found to reduce the maneuvering time dramatically. Finally, the hybrid control with reaction wheels and thrusters are considered. The simulation results show that the simultaneous actuation of reaction wheels and thrusters with varying time-sharing logic reduces the maneuvering time enormously. Spacecraft model is Korea Multi-Purpose Satellite (KOMPSAT)-2 which is being developed in Korea as an agile maneuvering satellite.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4214-4223
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• 2012

The argument related to the use of real and anonymous names on the Internet bulletin board has recently become a main issue. When using real names, it is possible to violate free discussion and privacy. Also, when using anonymous names, it is possible to have the reverse function of the Internet in regard to the use of malicious replies or the distribution of false ideas. Therefore, this paper has made it possible to prevent the spread of the user's personal information and execute the single log-in process by using the XML-token method which is one of the SSO technologies. Also, by issuing virtual IDs and forming the path when establishing tokens, the anonymous bulletin board which provides anonymity with a conditional tracing process has been suggested. After analyzing the performance of visitor numbers at authentication time, the anonymous bulletin board based on the group signature method showed the average response rate of 0.72 seconds, 0.18 seconds, which was suggested scheme. In the authentication time 4-5 times faster response speed, respectively. Also, since the suggested system does not have to provide a single authentication process or make the user provide his or her signature, the level of user's convenience seems to be much higher. Such a result shows that the system suggested on the anonymous bulletin board has a more appropriate level of user's convenience.

• Journal of KIISE:Software and Applications
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• v.32 no.12
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• pp.1283-1291
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• 2005

One of the problems in boosting Java performance using a Just-in-Time (JIT) compiler is removing redundant array bound checks. In conventional static compilers, many powerful algorithms have been developed, yet they are not directly applicable to JIT compilation where the compilation time is part of the whole running time. In the current JIT compilers, we tan use either a naive algorithm that is not powerful enough or an aggressive algorithm which requires the transformation into a static single assignment (SSA) form of programs (and back to the original form after optimization), thus causing too much overhead not appropriate for JIT compilation This paper proposes a new algorithm based on an inequality graph which can eliminate array bounds check codes aggressively without resorting to the SSA form. When we actually perform this type of optimization, there are many constraints in code motion caused by the precise exception rule in Java specification, which would cause the algorithm to miss many opportunities for eliminating away bound checks. We also propose a new method to overcome these constraints.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.12
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• pp.103-112
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• 2018

High-rise mixed-use buildings are consisted of various facilities and circulations. Since various facilities and circulations are planned in a single site, circulation planning should be established after identifying the exact characteristics of facility and circulation. To this end, the components of the circulation planning in accordance with the formation of facility types are analyzed through the survey of experts based on Delphi Method. To identify the characteristics of the mixed-use buildings, by figuring out how the elements of circulation planning which are sought to be important by the planner has been reflected through analysis of the correlation between two sections. Researching on the circulation between two sections through Delphi Method and reflected circulation planning, it reaches the conclusion that the circulation of planning on the subject building is applied following the importance. In other words, the components of circulation planning which were sought to be important by the planner are reflected significantly when they planned the circulation planning on that mixed-use buildings. However, in case of design on the outdoor vehicle circulation, minimizing on the vehicle circulation at the 1st floor is not applied for the majority of the subject buildings different from the importance. In early 2000, high end residential buildings designed for mixed-use building have been specialized at vehicle-centered outdoor space and hotel style drop-off. Contrastively, sizable outdoor space at the 1st floor is designed to open to the residents and the local by minimizing the vehicle circulation in recent. Finally it shows that the way of circulation planning has been changed in accordance with time and trend.

• Journal of Korean Society for Quality Management
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• v.10 no.2
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• pp.2-9
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• 1982

In principle the methods of increasing the reliability of complex system can be classified into the following four basic methods: (1) using the stand-by redundancy; (2) decreasing the failure rate of the system; (3) decreasing the time of continuous operation; (4) decreasing the mean repair time. Among the above four methods, it is generally known that the method of stand-by redundancy is the most effective general, to increase the reliability of systems. Therefor this paper aims to compare the gain in reliability which is achieved by applying stand-by redundancy with other methods, and to show the characteristics of each method From the comparison of the methods of increasing reliability, the following important facts are found: When the method of stand-by redundancy is used to increase the reliability of complex systems intended for long-term operation, a hight multiplicity of stand-by redundancy is required. Thus an increase of the reliability of complex system by applying stand-by redandancy is realized at the expense of characteristics such as weight, size, cost, increased complexity of operation conditions. And this property restricts its use in systems which are critical with respect to weight, size, cost or operation conditions. The method of stand-by redundancy is the most effective when this method is used to increase the reliability of complex systems intended for short-term operation, and the method of decreasing failure rate is the most effective when it is used to increase the reliability of systems intended for long-term use. The methods of increasing reliability discussed in this paper make it possible to make highly reliable systems. But it is not possible to make a highly reliable system using a single method of increasing reliability, even if it is the most effective one. Therefore it is recommended to use all or a majority of the above four methods by choosing it in accordance with the properties of the system under construction.