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In this study, the temperature and thermal stress fields of an internal combustion hot blast stove were calculated and analysed. Turbulent, species transport, chemical reaction, radiation, and porous media models were implemented in a computational fluid dynamics model. Thermal boundary conditions on the structure of the hot blast stove were calculated based on the analytic adiabatic Y-plus method. A method to interpolate the thermal boundary conditions to a finite element mesh was developed, and the boundary conditions were mapped through the proposed method. In the on-gas period, the vortex was generated in the dome, and it made the variation of the temperature field in the checker chamber. The maximum temperature of the flue gas reached 1841 K in the on-gas period. In the on-blast period, the flow was considerably even compared to the on-gas period, and the average blast temperature reached 1345 K. The outer region of the checker chamber is shown to be continuously exposed to a higher temperature, which makes the region the main domain in managing the deterioration of the refractory linings. The shell temperature did not change during the operation due to the lower thermal diffusivity of the refractory linings, where the inner surface of the refractory had a maximum temperature change from 1441 K to 1659 K. The maximum temperature of the shell was 418.4 K at the conical region of the checker chamber side. The conical region had the higher maximum and middle principal thermal stresses due to the presence of a large temperature gradient around the conical region, where the largest maximum and middle principal stresses were 300.6 MPa and 192.0 MPa, respectively. The conical region was found to be a significant area of interest where it had a higher temperature and thermal stress.

Purpose Paint drying is a very important process in an industry where shorter drying time for productivity and lower energy consumption for production cost are required while maintaining the product’s painting quality. In the present study, a drying process in a line-type paint drying furnace equipped with nozzles for hot air supply and moving conveyer belt to dry painted automotive parts is numerically simulated for the flow and heat transfer inside the furnace to evaluate the quality of the drying or baking at the end of the drying process in a production line. Design/methodology/approach A baking window for a specific paint is used for judging the local degree of baking (DOB) of the painted parts, which can be useful to identify under-baked or over-baked locations of the painted parts, and hence the quality of the baking process. Findings Numerical results of a time history of temperatures at two monitoring points on the painted parts were obtained and compared to the measured data in an actual furnace and showed good agreement. Three types of paints were considered in the present study and numerical results showed different drying characteristics. In addition to the original furnace nozzle configuration, two more furnace nozzle configurations with different numbers, direction and speed of hot air supply were simulated to improve the furnace’s drying performance. As a result, a newly suggested nozzle configuration with quick drying paint can give us a remarkable improvement in surface averaged DOB compared to the original nozzle configuration with original paint. Originality/value The present simulation technique and DOB methodology can be used for the optimal design of a drying furnace.

To detect the outer membrane protein (OMP), which plays a key role in carbapenem resistance, whole-genome and transcriptome analysis of the clinical carbapenem-resistant Klebsiella pneumoniae was carried out. The index strain lacked both OmpK35 and OmpK36, whereas the other strains lacked only OmpK35. After SDS-PAGE, the putative OMP bands were excised and identified as OmpA and OmpK36. MALDI-TOF MS showed peaks at ∼36 and ∼38 kDa that corresponded to OmpA and OmpK36, respectively. In all the strains except YMC2014/03/P345, the ∼38 kDa peaks were present. The K. pneumoniae ATCC 13883 isolate showed three bands on SDS-PAGE and three corresponding peaks on MALDI-TOF MS. The additional third peak at ∼37 kDa corresponding to OmpK35 was observed. To verify OmpK35 peak detection in other K. pneumoniae isolates by MALDI-TOF MS, we analyzed six strains from our laboratory’s strain bank. Whole genome sequence indicated that only two isolates had intact OmpK35. Both MALDI-TOF MS and SDS-PAGE did not show a ∼37 kDa peak or an OmpK35 band as observed in the K. pneumoniae ATCC 13883 isolate. Separation using SDS-PAGE showed a single peak representing OmpA. Therefore, both SDS-PAGE and MALDI-TOF MS were not completely reliable for OMP detection because they fail to detect OmpK35. To the best of our knowledge, this is the first report on the performance of SDS-PAGE and MALDI-TOF MS for the detection of OMP’s using whole-genome and RNA sequencing analyses.

Light weight aluminum has shown high applicability in the automobile industry for high fuel efficiency. However, the manufacturing of aluminum is limited by the deburring process owing to the difficulty in employing wet blasting. In this paper, we present experimental and computational studies on the deburring process of wet blasting for aluminum. The process conditions are analyzed to achieve high deburring performance that minimizes the surface damage. Parameters of wet blasting with a significant influence on the deburring process are investigated and a promising deburring technique for aluminum is proposed.

Ultracapacitors (UCs), known by different names such as supercapacitors, electrochemical double-layer capacitors, double-layer capacitors or electrochemical capacitors, have the potential to meet the high pulse power capability of the energy-storage systems for automotive applications. The primary advantages of UCs are higher power density and longer shelf and cycle life as compared to those of batteries. In the high pulse power operations for automotive applications, a large amount of heat is produced inside a UC cell. Because the lifetime and performance of a UC depend strongly on temperature, it is important to predict accurately the thermal behaviors of a UC for the efficient and reliable systems integration from an application perspective. In this work, a three-dimensional thermal model is presented to predict the thermal behaviors of the UC. Both of the irreversible and reversible heat generations inside the UC cell are considered. The effective density and specific heat capacity of the various compartments of the cell are estimated based on the mass fractions of the components of each cell compartment. The effective thermal conductivities of the various compartments of the cell are estimated based on the equivalent networks of parallel and series thermal resistances of the cell components. The validation of the three-dimensional thermal model is provided through the comparison of the modeling results with the experimental IR image at various charge/discharge currents.

In the present study, the dispersion process of hydrogen leaking from an FCV (Fuel Cell Vehicle) in an underground parking garage is analyzed with numerical simulations in order to assess hazards and associated risks of a leakage accident. The temporal and spatial evolution of the hydrogen concentration as well as the flammable region in the parking garage was predicted numerically. The volume of the flammable region shows a non-linear growth in time with a latency period. The effects of the leakage flow rate and an additional ventilation fan were investigated to evaluate the ventilation performance to relieve accumulation of the hydrogen gas. It is found that expansion of the flammable region is delayed by the fan via enhanced mixing near the boundary of the flammable region. The present numerical results can be useful to analyze safety issues in automotive applications of hydrogen.

The aim of this work was to investigate the mechanism responsible for multidrug resistance in ST11 Klebsiella pneumoniae YMC 2013/7/B3993 containing multiple copies of ESBL genes using multiple parallel sequencing technology. In-depth analysis of the strain revealed multiple copies of ESBL genes, 2 copies of blaSHV-12 and 1 copy of blaCTX-M-15. Furthermore, 1 copy of blaOXA-9 and 3 copies of blaTEM-1 were found. The insertion of Tn1331 was detected, which consisted of blaOXA-9, blaTEM-1, aac(6')-lb-cr, and aadA1 genes. The acquisition of multiple copies of resistance genes was due to the insertion of transposons in the bacterial genome and plasmid. The genotypic analysis revealed that the isolates belonging to ST11 showed severe resistance phenotypes and greater dissemination potential. To the best of our knowledge, this is the first report demonstrating multiple copies of same ESBL genes in K. pneumoniae ST11 isolate. Furthermore, massive parallel sequencing studies of genetic factors to enhance the fitness of this type strain would be warranted to determine whether ST11 K. pneumoniae can spread the KPC-type gene.

In the present study, a numerical simulation to analyze mixing performance inside an industrial mixer was investigated for various geometry of turbine impellers. Various pitching angles and various types of turbine blades were considered in the simulation. In order to model the rotation of impeller, the Multiple Reference Frames (MRF) technique was used. For evaluation of the effect of various shapes on the mixing performance, dimensionless coefficient such as flow coefficient, circulation coefficient, power coefficient, pumping effectiveness and circulation effectiveness were used. From the results, the effect of pitching angle of a pitched turbine impeller was to give best pumping effectiveness around 30o pitching angle, whereas best circulation effectiveness around 65o pitching angle. Dual pitched turbine impeller showed best performance in both pumping effectiveness and circulation effectiveness among impeller types considered in the present study. † 1. 서 론 전통적으로 교반기는 단일 또는 다상의 물질을 고루 섞어주기 위해 사용되는 기계로서 주로 식품, 생화학, 금속, 수 처리 등 산업 전반에 널리 사용된다. 이러한 교반기는 용도나 기능에 따라 내부의 혼합현상이 매우 다양하게 일어나기 때문에 임펠러나 교반 용기 등의 내부 형상과 작동 조건을 고려하여 설계되어야 한다. 사용 환경에 따라 최적의 교반성능을 내기 위해서는 교반기 내부의 유동특성 및 이에 따른 교반결과에 대한 분석이 이루어져야 한다. 최근 컴퓨터의 발달과 함께 수치해석의 해석 신뢰성이 높아지면서, 교반기 연구에 대하여 수치해석적인 방법은 실험과 경험에 의한 방법의 대안이 되고 있다. 이러한 수치해석 방법은 해석 결과를 시간과 공간에 따라 분석할 수 있는 장점을 가지고 있기 때문에 최근 교반기 연구에 많이 이용되고 있다. 교반기에 대한 이러한 수치해석적 연구로, 김치겸 등

Klebsiella pneumoniae is responsible for numerous infections caused in hospitals, leading to mortality and morbidity. It has been evolving as a multi-drug resistant pathogen, acquiring multiple resistances such as such as horizontal gene transfer, transposon-mediated insertions or change in outer membrane permeability. Therefore, constant efforts are being carried out to control the infections using various antibiotic therapies. Considering the severity of the acquired resistance, we developed a panel of strains of K. pneumoniae expressing different resistance profiles such as high-level penicillinase and AmpC production, extended spectrum beta-lactamases and carbapenemases. Bacterial strains expressing different resistance phenotypes were collected and examined for resistance genes, mutations and porin alterations contributing to the detected phenotypes. Using the Massive parallel sequencing (MPS) technology we have constructed and genotypically characterized the panel strains to elucidate the multidrug resistance. These panel strains can be used in the clinical laboratory as standard reference strains. In addition, these strains could be significant in the field of pharmaceuticals for the antibiotic drug testing to verify its efficiency on pathogens expressing various resistances.

In the present study, the dispersion characteristics of hydrogen leakage from a Fuel Cell Vehicle (FCV) were analyzed by numerical simulation in order to assess the risk of a hydrogen leakage incident in a long road tunnel. In order to implement the worst case of hydrogen leakage, the FCV was located at the center of a tunnel, and hydrogen was completely discharged within 63 seconds. The Leakage velocity of hydrogen was adopted sub-sonic speed because that the assumption of the blockage effect of secondary device inside a vehicle. The temporal and spatial evaluation of the hydrogen concentration as well as the flammable region in a road tunnel was reported according to change of ventilation operating conditions. The hydrogen was blended by supply air form a ventilation fan, however, the hydrogen was discharged to outside in the exhaust air. It is observed that the efficiency way to eliminate of hydrogen is supply air operating condition under the hazardous hydrogen leaking incident. The present numerical analysis can be provided useful information of ventilation under the hydrogen leaking situation.

In this study, three-dimensional transient numerical simulations were carried out for a paint drying system of vehicle. The vehicle on assembly line passes through the drying system consisting of hot and cool air blow region. For the moving motion of the vehicle, moving of inlet boundary condition and MRF technique are used. The transient distribution of temperature and velocity in the drying system were predicted numerically. In order to validate the numerical results, transient distribution of the vehicle surface temperature was compared with experimental data, showing a good agreement. As a result of present study, optimal operating condition of the drying system are to be suggested.

In the automotive manufacturing process, the paint drying process is very important to improve the appearance of the vehicle. In the present study, the fluid flow and heat transfer around a vehicle were numerically investigated for the purpose of predicting the drying performance of the paint drying process. In order to simulate the operating conditions of the paint drying process, the following techniques were used: relative moving boundary conditions, multiple reference frames, and conjugated heat transfer. The present numerical method was verified by comparing the numerical results of the temperature at several monitoring points on a vehicle, while using the experimental data. To evaluate the drying performance quantitatively, the absorbed heat energy that is closely related to the drying of paint was obtained from the numerical simulation. It was found that the drying performance is greatly affected by operating conditions such as the temperature and flow rate of blowing air. To improve the drying performance, the operating conditions of the paint drying process were optimized using the numerical results of various operating conditions.Copyright © 2013 by ASME

Ultracapacitors, also known as supercapacitors, have the potential to meet the increasing power requirements of energy-storage systems for automotive applications. As compared to batteries, ultracapacitors offer a higher power density, higher efficiency, and longer shelf and cycle life. Because the performance of an ultracapacitor depends on temperature, it is important to calculate accurately the thermal behavior of a single ultracapacitor cell and the module composed of multiple ultracapacitor cells for the efficient and reliable systems integration of an ultracapacitor in automotive applications. In this work, modeling is performed to study the thermal behavior of an ultracapacitor module. The ultracapacitor module is subject to the charge/discharge cycling with constant-current between 190V and 380V. The validation of the modeling approach is provided through the comparison of the modeling results with the experimental measurements. Fig. 1 shows the schematic diagram of the ultracapacitor module composed of the 136 ultracapacitor cells (2.8V/350F) from LS Mtron Ltd. In Fig. 2, the variation of surface temperature with time from the experiment is compared with that from modeling during the charge-discharge cycles with the constant current of 10 A. Figure 1

Electricity generated from renewable sources such as wind and solar power is intermittent. Electrical energy storage devices are therefore critical for effectively leveling the intermittent nature of renewable energy sources. Ultracapacitors (UCs), also known as supercapacitors, have the potential to meet the power requirements for the grid-scale renewable energy storage systems. As compared to batteries, UCs offer a higher power density, higher efficiency, and longer shelf and cycle life. Because the performance of UC depends on temperature, it is important to calculate accurately the thermal behaviors of an individual UC cell in the module composed of multiple UC cells for the efficient and reliable systems integration of UC in grid applications. In this work, modeling is performed to study the thermal behaviors of the module composed of 18 UC cells. The thermal behaviors of the ultracapacitor cells in the module are measured during the charge/discharge cycling of the ultracapacitor module with constant-current. The charge/discharge current values examined are 50, 100, 150, and 200 A. The validation of the modeling approach is provided through the comparison of the modeling results with the experimental measurements. Fig. 1 shows the schematic diagram of the ultracapacitor module composed of the 18 ultracapacitor cells (3.7V/3000F) from LS Mtron Ltd. (Anyang, Republic of Korea). The red dots with numbers in Fig. 1 indicate the positions for thermocouple measurement. In Fig. 2, the variations of surface temperature with time from the modeling are compared with those from the experiment during the charge-discharge cycles with the constant current of 200 A. The modeling results shown in Fig. 2 are in good agreement with the experimental measurements. Figure 1

Ultracapacitors, also known as supercapacitors, have the potential to meet the increasing power requirements of energy-storage systems for automotive applications. As compared to batteries, ultracapacitors offer a higher power density, higher efficiency, and longer shelf and cycle life. Because the performance of an ultracapacitor depends on temperature, it is important to calculate accurately the thermal behavior of a single ultracapacitor cell and the module composed of multiple ultracapacitor cells for the efficient and reliable systems integration of an ultracapacitor in automotive applications. In this work, modeling is performed to study the thermal behavior of an ultracapacitor module. The ultracapacitor module is subject to the charge/discharge cycling with constant-current between 1.35V and 2.7V. The validation of the modeling approach is provided through the comparison of the modeling results with the experimental measurements. Fig. 1 shows the schematic diagram of the ultracapacitor module composed of the 18 ultracapacitor cells (3.7V/3000F) from LS Mtron Ltd. In Fig. 2, the variation of surface temperature with time from the experiment is compared with that from modeling during the charge-discharge cycles with the constant current of 200 A. Figure 1