• Journal of Korean Institute of Industrial Engineers
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• v.34 no.2
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• pp.190-204
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• 2008

Recently, it has been strongly required to establish a systematic and sustainable performance investigation and evaluation framework on governmental funding projects for IT small and medium-sized enterprises. In this paper, Data Envelopment Analysis (DEA) models are adopted for performance evaluation on governmental funding projects for IT small and medium-sized enterprises. A new data structure is proposed for the DEA performance evaluation. Generally, in using DEA models, DEA multipliers restriction is critical to achieve the reliability of DEA optimal solutions. Based on the outputs and inputs considered in this study, Acceptance Region (AR) constraints are generated and incorporated into the DEA models so as to improve the reliability of DEA efficiency scores. Associated with AR Type I (AR-I), AR Global Model (ARGM) constraints, DEA/ (AR-I, ARGM) models are designed and then sensitivity analysis follows investigating the robustness of DEA efficiency scores relating to AR constraints adjustment. Finally, a performance evaluation is illustrated regarding governmental direct funding projects from Ministry of Information and Communication (MIC) in Korea where each project unit (i.e. Decision Making Unit (DMU)) is determined whether it is efficient or not. By using DEA/(AR-I, ARGM) models designed in this paper, robustly efficient DMUs are gradually identified according to the successive AR constraints adjustment. Among 25 DMUs, results show that 6 DMUs such as B, E, G, Q, S, Y are determined as robustly efficient against AR constraints intermediate adjustment.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.11
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• pp.46-56
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• 2010

The present research works investigated into the low velocity impact characteristics of DP 780 high strength steel sheet with 1.7 mm in thickness subjected to free boundary condition using three-dimensional finite element analysis. Finite element analysis was carried out via ABAQUS explicit code. Hyper-elastic model and the damping factor were introduced to improve an accuracy of the FE analysis. An appropriate FE model was obtained via the comparison of the results of the FE analyses and those of the impact tests. The influence of the impact energy and nose diameter of the impact head on the force-deflection curves, impact time, absorption characteristics of the impact energy, deformation behaviours, and stress-strain distributions was quantitatively examined using the results of FE analysis. The results of the FE analysis showed that the absorption rate of impact energy lies in the range of the 70.7-77.5 %. In addition, it was noted that the absorption rate of impact energy decreases when the impact energy increases and the nose diameter of the impact head decreases. The local deformation of the impacted region was rapidly increased when the impact energy was larger than 76.2 J and the nose diameter was 20 mm. A critical impact energy, which occur the instability of the DP780, was estimated using the relationship between the plastic strain and the impact energy. Finally, characteristics of the plastic energy dissipation and the strain energy density were discussed.

• Environmental Engineering Research
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• v.23 no.2
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• pp.143-149
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• 2018

Air quality conditions and pollution status have been evaluated in the industrial area between Sharjah and Ajman border in UAE. Daily concentrations of $O_3$, CO, $NO_2$, $SO_2$, $PM_{2.5}$, $PM_{10}$, Total Volatile Organic Compounds (TVOC) and Total Suspended Particulate (TSP) have been monitored from Sept. 2015 to April 2016. The monthly average concentrations of $O_3$, CO, $NO_2$, $SO_2$, TVOC were within the UAE ambient air quality standards during the survey period. However, $PM_{10}$ and TSP levels exceeded the recommended limits in Sept. 2015, Oct. 2015 and March 2016. Temporal variations in air quality parameters showed highest levels in March 2016 for $PM_{2.5}$, $PM_{10}$, $NO_2$, TVOC and TSP, whereas $O_3$, $SO_2$ and CO showed relatively low values in this month. $PM_{2.5}$ levels in ambient air were above the EPA guideline of $35{\mu}g/m^3$ in all months. $PM_{2.5}$ was the critical ambient air pollutant with Index for Pollutant ($I_p$) values varying from 103-209, indicating Air Quality Index categories of unhealthy for sensitive groups (62.5%) to unhealthy (25%) to very unhealthy (12.5%). The $I_p$ average values of $PM_{2.5}$ decreased from Sept. 2015 to reach lowest value in Dec. 2015 before increasing gradually, peaking in March 2016. These results suggest the potential health risks associated with $PM_{2.5}$ is low in winter, where the prevailing meteorological conditions of lower temperatures, higher humidity, higher wind speed reduced particulate matter. The results revealed the industrial area is impacted by anthropogenic and natural sources of particulate matter.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.8
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• pp.1-7
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• 2003

The numerical simulation of flow-filed around a square cylinder near a wall with $\varepsilon$-SST turbulence model is carried out in this study. The newly suggested $\varepsilon$-SST turbulence model that modifies the original SST turbulence model is proved to yield more accurate results than the other 2-equation turbulence models in large separation region around a bluff body. Therefore, $\varepsilon$-SST turbulence model can be effectively applied for predicting the flow-fields with large separation. And it is found that vortex shedding is suppressed below the critical gap height, the Strouhal number is affected by the gap height and the wall boundary layer thickness.

• Journal of Biomedical Engineering Research
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• v.31 no.2
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• pp.94-98
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• 2010

In magnetic resonance electrical impedance tomography (MREIT), a current-injection MR imaging method is adopted to produce a cross-sectional image of an electrical conductivity distribution in addition to MR images. The purpose of this study was to test the feasibility of MREIT for differentiating the canine lung parenchyma without and with pneumonia. Three normal healthy beagles and two mixed breed dogs with pneumonia were used. After attaching electrodes around the chest, we placed the dog inside our MR scanner. We injected as much as 30 mA current in a form of short pulses into the chest region. Reconstructed conductivity images of normal canine lungs exhibit a peculiar pattern of a relatively coarse salt and pepper noise. On the contrary, conductivity images of pneumonic canine lungs show significantly enhanced contrast of the lesions while the corresponding MR images show a little bit of contrast in the middle and caudal lung parenchyma due to the accumulation of pleural fluid. This preliminary study indicates that MREIT imaging of the chest may deliver unique new diagnostic information.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.3
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• pp.197-207
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• 2005

Design analysis for underground spaces requires evaluating stability related to heading collapses. A failure mode is one of the critical factors in the conventional methods of stability evaluation. Identification of failure modes is, therefore, essential in securing safe construction. In this study failure modes at the tunnel heading in cohesionless soils are investigated using physical model tests for various tunnel depths and ground surface inclinations. Test results showed that the effect of depth and the inclination of ground surface on a failure mode are of significance. It is identified that, with an increase in depth, failure modes become localized in a region close to tunnel face. It is also known that an increase in the inclination of ground surface results in inclined an d wide failure modes. Numerical simulation of laboratory tests was performed, and shown that the numerical analysis is useful in identifying the heading failure modes, particularly for large underground spaces.

• World Technopolis Review
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• v.1 no.1
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• pp.56-64
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• 2012

This paper provides a case study to explore the Kitakyushu case as a good referential example on STP development for rejuvenation of declining industrial city. The major data for the case, basically, has been sourced from some materials published by the municipality of Kitakyushu City, the website of the Kitakyushu Science and Research Park (KSRP) etc. The City of Kitakyushu has promoted the KSRP development to overcome industrial decline and stimulate city renaissance as a new industrial city. The core of the development was to develop a high-level education and research environment by gathering several HEIs into one campus. Based on the environment, the Kitakyushu Foundation for the Advancement of Industry and Science and Technology (FAIS) played the critical role as a coupler to make various networks and boost industry-academiaadministration innovation. The KSRP, and then, has been designated as a project area of some cluster projects initiated by the central government. It means that local projects can be synchronized, synergized and synthesized with national projects in the KSRP. In addition, through a series of the environmental approach from the Kitakyushu Eco-town Project to the Low Carbon Society Project, the development of the KSRP is being extended into the region. In the Kitakyushu case, networking is the essence of the KSRP development from the planning stage. First of all, the plan put emphasis on networking of academia for the knowledge creation based on competitive collaboration that is expected as the mainspring of rejuvenating declining industrial area and making a new industrial city that the plan aimed. Then, the roles of two organizations are very important for networking, especially networking of networks: the Campus Management Committee as an interface and the FAIS as a coupler. STP development without some strategic considerations for networking as the way of interaction among its participants cannot be a tool to promote innovation and rejuvenate a declining industrial area. The Kitakyushu case mentioned above explains the matter clearly.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.2
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• pp.85-94
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• 2004

Experimental study on combustion characteristics of double swirl coaxial injectors has been conducted for the assessment of critical injector design parameters. A reusable, unielement thrust chamber has been fabricated with a water-cooled copper nozzle. Two principal design parameters. a swirl angle and a recess length, have been investigated through hot firing tests for the understanding of their effects on high pressure combustion. Clearly, both parameters considerably affect the combustion efficiency, dynamics and hydraulic characteristics of an injector. Internal mixing of propellants in a recess region increases combustion efficiency along with the increase of a pressure drop required for flowing the same amount of mass flow rates. It is concluded that pressure buildup due to flame can be released by the increase of LOx flow axial momentum or the reduction of a recess length. Dynamic pressure measurements of the thrust chamber show varied dynamic behaviors depending on injector configurations.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2869-2873
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• 2014

Background: Human papillomavirus (HPV) integration within the E2 gene has been proposed as a critical event in cervical carcinogenesis. This study concerned whether HPV16 status and E2 gene intactness are predictive of radiation response in patients with cervical cancer. Materials and Methods: Biopsies of 44 patients with cervical cancer were collected before or after radiotherapy. The presence of HPV16 was assessed by polymerase chain reaction (PCR) using specific primers for the L1 region. E2 disruption was detected by amplifying the entire E2 gene. Results: HPV16 DNA was found in 54.5% of the clinical samples. Overall, 62.5% of the HPV16 positive tumors had integrated viral genome and 37.5% had episomal genome. There was a tendency of increase of HPV16 E2 negative tumors compared with HPV16 L1 ones in advanced stages (75% versus 20% in stage III respectively). Detection of E2 gene appeared influenced by the radiotherapy treatment, as the percentage of samples containing an intact HPV16 E2 was more frequent in pretreated patients compared to radiotherapy treated patients (66.6% versus 20%). The radiation therapy caused an eight-fold [OR= 8; CI=1.22-52.25; p=0.03] increase in the risk of HPV16 genome disruption. The integration status is influenced by the irradiation modalities, interestingly E2 disruption being found widely after radiotherapy treatment (75%) with a total fractioned dose of 50Gy. Conclusions: This study reveals that the status of the viral DNA may be used as a marker to optimize the radiation treatment.

• Ocean and Polar Research
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• v.25 no.1
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• pp.63-74
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• 2003

The build-up of the heat field in shallow coastal water due to a point source has been investigated using an analytical solution of a time-integral form derived by extending the solutions by Holley(1969) and also presented in Harleman (1971). The uniform water depth is assumed with non-isotropic turbulent dispersion. The alongshore-flow is assumed to be uni-directional, spatially uniform and oscillatory. Due to the presence of the oscillatory alongshore-flow, the heat build-up occurs in an oscillatory manner, and the excess temperature thereby fluctuates in that course and even in the quasi-steady state. A series of calculations reveal that proper choices of the decay coefficient as well as dispersion coefficients are critical to the reliable prediction of the excess temperature field. The dispersion coefficients determine the absolute values of the excess temperature and characterize the shoreline profile, particularly within the tidal excursion distance, while the decay coefficient determines the absolute value of the excess temperature and the convergence rate to that of the quasi-steady state. Within the e-folding time scale $1/k_d$ (where $k_d$ is the heat decay coefficient), heat build-up occurs more than 90% of the quasi-steady state values in a region within a tidal excursion distance (L), while occurs increasingly less the farther we go to the downstream direction (about 80% at 1.25L, and 70% at 1.5L). Calculations with onshore and offshore discharges indicate that thermal spreading in the direction of the shoreline is reduced as the shoreline constraint which controls the lateral mixing is reduced. The importance of collecting long-term records of in situ meteorological conditions and clarifying the definition of the heat loss coefficient is addressed. Interactive use of analytical and numerical modeling is recommended as a desirable way to obtain a reliable estimate of the far-field excess temperature along with extensive field measurements.