• Journal of Gastric Cancer
• /
• v.1 no.1
• /
• pp.44-49
• /
• 2001

Purpose: Quality of life (QOL) assessment should be applied in surgical settings to compare treatment options. We compared QOL after a subtotal versus a total gastrectomy for gastric cancer to identify which resection would produce a better QOL for the patient. Patients and Methods: We studied 362 patients with no evidence of recurrent disease after curative surgery for gastric cancer. The QOL was measured by assessing patient health perceptions according to the Spitzer index and Troidl score and by treatment-specific symptoms according to Korenaga and others with some modifications. High scores reflect a better QOL. Results: The mean score of the Spitzer index was $8.87\pm1.36$ after a subtotal gastrectomy and $8.80\pm1.23$ after a total gastrectomy. More than $80\%$ of the patients in both groups maintained good quality of life when measured by the Spitzer index. The mean Troidl score was $10.41\pm2.12$ after a subtotal gastrectomy and $9.79\pm2.16$ after a total gastrectomy (p=0.033). Swallowing difficulty was more frequent after a total gastrectomy (p=0.002). There was a statistically significant difference in the meal size (p=0.044). Other variables of the Troidl score revealed no statistically significant differences. Dizziness was significantly more frequent after a total gastrectomy than after a subtotal gastrec tomy (p=0.009). Conclusion: We conclude that in terms of postoperative quality of life, a subtotal gastrectomy has advantages over a total gastrectomy. In those cases where an adequate proximal safety margin can be achieved by a subtotal gastrectomy, that procedure is preferable to a total gastrectomy.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.19 no.2
• /
• pp.129-136
• /
• 2016

Floating offshore structures keep its position by a mooring system against various kind of environmental loadings. For this reason, a reliable design of the mooring system is a key factor for initial design stage of a floating structure. However, there exists possibility of mooring failure, even the system is designed with enough safety margin, due to the unexpected extreme environmental conditions or long-term fatigue loadings. The breaking of one of the mooring lines may change the tension level of the other mooring lines, which can potentially result in a progressive failure of the entire structure. In this study, time domain numerical simulation of 10MW class wind-wave hybrid platform was carried out with partially broken mooring line. Overall platform responses and variations of the mooring line tension were numerically evaluated.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.8 no.3
• /
• pp.67-75
• /
• 2008

This research is to develop the steel-concrete composite lining board using section shape steel. This lining board adopts section shape steel, rectangular pipe and H-beam, instead of roll-formed steel member commonly used in other composite lining board. Consequently, it reduces fabrication effort. Efficient section which can reduce the weight of steel of the lining board is made by placing the neutral axis of the section near the lower surface of concrete. Behavior of composite section is improved by adding bolts as shear connector. Static and fatigue tests were conducted to verify the performance of the composite lining board developed. The test results indicate that serviceability as well as safety of the lining board developed is secured with good margin and reduction of steel weight can be made about 27% compared with other composite lining boards.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.181-184
• /
• 2016

This study is to compensate for inaccuracies in accordance with the change in the deviation correction value due to the movement and location of the ship cargo, equipment of the vessel, and eliminating the inconvenience of hand. By modifying the deviation through the simplification and automation was planned for accuracy and ease of modification of the modified value. The main method used is charted by measuring 24 direction and inputting the value of magnetic compass direction in automatic deviation-correcting apparatus manually or automaticallyThe measured values are exhibited in Table data and made it possible to calculate accurate correction value deviation. From this it can make deviation table having the margin of error within ${\pm}3^{\circ}$in all regions of the world And this table will help to navigational safety and economy under the unavailable or limited gyro contion.

• Nuclear Engineering and Technology
• /
• v.48 no.1
• /
• pp.55-63
• /
• 2016

Calculation of the core neutronic parameters is one of the key components in all nuclear reactors. In this research, the energy spectrum and spatial distribution of the neutron flux in a uranium target have been calculated. In addition, sensitivity of the core neutronic parameters in accelerator-driven subcritical advanced liquid metal reactors, such as electron beam energy ($E_e$) and source multiplication coefficient ($k_s$), has been investigated. A Monte Carlo code (MCNPX_2.6) has been used to calculate neutronic parameters such as effective multiplication coefficient ($k_{eff}$), net neutron multiplication (M), neutron yield ($Y_{n/e}$), energy constant gain ($G_0$), energy gain (G), importance of neutron source (${\varphi}^*$), axial and radial distributions of neutron flux, and power peaking factor ($P_{max}/P_{ave}$) in two axial and radial directions of the reactor core for four fuel loading patterns. According to the results, safety margin and accelerator current ($I_e$) have been decreased in the highest case of $k_s$, but G and ${\varphi}^*$ have increased by 88.9% and 21.6%, respectively. In addition, for LP1 loading pattern, with increasing $E_e$ from 100 MeV up to 1 GeV, $Y_{n/e}$ and G improved by 91.09% and 10.21%, and $I_e$ and $P_{acc}$ decreased by 91.05% and 10.57%, respectively. The results indicate that placement of the Np-Pu assemblies on the periphery allows for a consistent $k_{eff}$ because the Np-Pu assemblies experience less burn-up.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.36 no.9
• /
• pp.1087-1094
• /
• 2012

This study deals with structural analysis and testing under loading conditions calculated by computational fluid dynamics for a small composite blade that is utilized in a dual rotor wind turbine system. First, the aerodynamic forces were analyzed at the rated and cutout wind speed to identify the bending moment distribution along the blade length in previous research. Then, full-scale structural tests were conducted according to IEC 61400-2 to evaluate the structural integrity of the composite blade. These results were compared with finite element analysis to identify the accuracy of the structural analysis. Based on these results, it was revealed that the existing blade has a very high safety margin. Then, the layup of the composite blade was redesigned and analyzed using finite element analysis to achieve structural integrity and economic efficiency.

• Korean Journal of Metals and Materials
• /
• v.47 no.9
• /
• pp.533-541
• /
• 2009

Materials used for a reactor pressure vessel(RPV) are required high strength and toughness, which determine the safety margin and life of a reactor. Ni-Mo-Cr low alloy steel shows better mechanical properties than existing RPV steels due to higher Ni and Cr contents compared to the existing RPV steels. The present study focuses on effects of Ni, Cr contents on the cleavage fracture toughness of Ni-Mo-Cr low alloy steels in the transition temperature region. The fracture toughness was characterized by a 3-point bend test of precracked Charpy V-notch(PCVN) specimens based on ASTM E1921-08. The test results indicated that the fracture toughness was considerably improved with an increase of Ni and Cr contents. Especially, control of Cr content was more effective in improving fracture toughness than manipulating Ni content, though Charpy impact toughness was changed more extensively by adjusting Ni content. These differences between changes in the fracture toughness and that in the impact toughness were derived from microstructural features, such as martensite lath size and carbide precipitation behavior.

• Journal of Microbiology and Biotechnology
• /
• v.10 no.6
• /
• pp.858-864
• /
• 2000

The purpose of the present study was to examine the efficacy and mechanism of the fraction IV cold ethanol fractionation and pasteurization ($60^{\circ}C$ heat treatment for 10h) steps, involved in the manufacture of albumin from human plasma, in the removal and/or inactivation of blood-born viruses. A variety of experimental model viruses for human pathogenic viruses, including the Bovine viral diarrhoea virus (BVDV), Bovine herpes virus (BHV), Murine encephalomyocarditis virus (EMCV), and Porcine parvovirus (PPV), were selected for this study. Samples from the relevant stages of the production process were spiked with the viruses, and the amount of virus in each fraction was then quantified using a 50% tissue culture infectious dose ($TCID_{50}$). The mechanism of reduction for the enveloped viruses (BHV and BVDV) during fraction IV fractionation was inactivation rather than partitioning, however, it was partitioning in the case of the non-enveloped viruses (EMCV and PPV). The log reduction factors achieved during fraction IV fractionation were ${\geq}6.9$ BHV, $\geq5.2$ for BBDV, 4.9 for EMC, and 4.0 for PPV. Pasteurization was found to be a robust and effective step in inactivating the enveloped viruses as well as EMCV. The log reduction factors achieved during pasteurization were $\geq7.0$ for BHV, $\geq6.1$ for BVDV, $\geq6.3$ for EMCV, and 1.7 for PPV. These results indicate that the production process for albumin has sufficient virus-reducing capacity to achieve a high margin for virus safety.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.46 no.2
• /
• pp.133-140
• /
• 2018

In this paper, we develop an automated software for in-plane structural analysis of composite laminated structures. The developed software supports various failure criteria and reports the analysis results considering user's convenience. It also provides batch job analysis function based on parallel processing technique. To verify the performance of the software, we compared margin of safety(MS) calculated in the software to those obtained from in-house method and the specimen experiment. As a result of comparisons, there was an error of less than 0.01 in the in-house method and it is within about ${\pm}10%$ with the specimen experiment. In addition, we confirmed the improvement of execution speed of batch job analysis based on parallel processing technique.

• Proceedings of the KIEE Conference
• /
• 2005.11b
• /
• pp.46-48
• /
• 2005

This paper discusses a probabilistic method for power system security assessment. The security analysis relates to the ability of the electric power systems to survive sudden disturbances such as electric short circuits or unanticipated loss of system elements. It consists of both steady state and dynamic security analyses, which are not two separate issues but should be considered together. In steady state security analysis including voltage security analysis, the analysis checks that the system is operated within security limits by OPF (optimal power flow) after the transition to a new operating point. Until now, many utilities have difficulty in including dynamic aspects due to computational capabilities. On the other hand. dynamic security analysis is required to ensure that the transition may lead to an acceptable operating condition. Transient stability, which is the ability of power systems to maintain synchronism when subjected to a large disturbance. is a principal component in dynamic security analysis. Usually any loss of synchronism may cause additional outages and make the present steady state analysis of the post-contingency condition inadequate for unstable cases. This is the reason for the need of dynamic studies in power systems. Probabilistic criterion can be used to recognize the probabilistic nature of system components while considering system security. In this approach. we do not have to assign any predetermined margin of safety. A comprehensive conceptual framework for probabilistic static and dynamic assessment is presented in this paper. The simulation results of the Western System Coordinating Council (WSCC) system compare an analytical method with Monte-Carlo simulation (MCS).