• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.17-28
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• 2007

To understand the spring freezing injury symptoms during sensitive growth stage and yield loss of barley and wheat, field tests were done by using vinyl mulching and natural cold weather. The growth stage sensitive were booting, spikelet differentiation and flower organ development stages for both crops. However, barley and wheat differed in their growth responses, in that barley was less affected than wheat. For instance, barley recorded 28 percent dead ears, 10 percent dead plants and 18 percent ear degenerations while wheat recorded higher values of 59 percent, 44 percent and 44 percent, respectively. Although there were no recorded froze-resistant varieties in both barley and wheat, some showed tolerance as their yields were not affected by freezing stress. The 'Chalbori' cultivars of barley and 'Geurumil' and 'Chokwang' cultivars of wheat recorded steady yields. The yield components of barley and wheat that were greatly affected by freezing stress were the number of spike per square and the number of grain per spike. The major cause of yield loss in Suwon 259 and Kangbori was the number of spike per square but not the number of grain per spike. The study showed, however, that both the number of spike per square and the number of grain per spike were vulnerable to freezing and that which contribute much to yield loss of barley and wheat.

• Journal of Welding and Joining
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• v.30 no.2
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• pp.59-64
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• 2012

Welding is an essential process in the automotive industry. Most welding processes that are used for auto body are spot welding and $CO_2$ welding are used in a small part. In production field, $CO_2$ welding process is decreased and spot welding process is increased due to welding quality is poor and defects are occurred in $CO_2$ welding process frequently. But $CO_2$ welding process should be used at robot interference parts and closed parts where spot welding couldn't. Because of the 0.65mm ~ 2.0mm thickness steel sheet were used in the automotive industry, poor quality of welding area such as burn through and under fill were happened frequently in $CO_2$ process. In this paper, we will study about the penetration depth which gives a huge impact on burn through changing a degree of base metal, welding position and torch angle. Voltage, current and welding speed were fixed but degree of base metal, welding position and torch angle were changed. And Cold- Rolled(CR) steel sheet was used. Penetration depth was analysed by multiple regression analysis to derive approximate calculations. And reliability of approximate calculations were confirmed through additional experiments. As the results of this research, we confirmed the effect of torch and plate angle to bead shape. And we present a possibility that can simulate more accurate to weld geometry, as deduced the verification equations that has tolerance of less than 21.69%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.104-112
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• 2020

Maize is thought to be an alternative crop to rice in paddy fields for efficient field management and maintenance of rice production at appropriate levels in Korea. Thus efforts to breed waterlogging-tolerant maize cultivars have been ongoing. However, molecular studies related to waterlogging tolerance are limited for developing molecular markers to select waterlogging tolerant maize varieties. In this study, we examined molecular biological changes of B73 in the V3 stage after immersion treatment for 7 days. Overall growth of maize was lower in treated samples compared to non-immersed control samples. The length of leaf and root decreased by 21.3% and 50.6%, respectively and the weight of root reduced by 21.6%. Soil plant analysis development (SPAD) value and chlorophyll content of leaf also decreased by 55.7% and 35.3%, respectively. Reactive oxygen species (ROS) content of root increased by 46.5% at 2 hours in immersion treatment. In addition, immersed roots were 2.5-fold thickened with additional aerenchyma formation in the cortex. In order to identify the causes of these changes, we performed a microarray and found increased expression of genes, such as WIP1, PMIP2, EXPA1, TPS1, and MAS1, in immersed samples. These differentially expressed genes and expression of previously reported genes, including ALDH2, Wusl1032, UP-1, UP-2, and CAT2 were further confirmed with qRT-PCR. Here, we report 7 differentially expressed genes after immersing treatment, which may be utilized as useful resources for breeding waterlogging- tolerant maize.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.692-696
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• 2017

The shape of press components is becoming increasingly complex due to customer demands, process shortening and cost savings. In addition, the stability of the pressing process frequently varies during mass production due to the influence of many factors. In order to ensure the process stability, it is necessary to establish a process in which reproducibility is realized in tolerance, which is sufficient for advance study of shape, material, press, mold and lubrication. However, unforeseen changes in process parameters cause disruptions in production line shutdowns and production planning. In this paper, we introduce a method to monitor a real time process by applying a sensor to a press mold. A non-contact type sensor for measuring the flow of a sheet material and an example of an experiment using the optical sensor which is highly applicable to mass production are presented. An optical sensor was installed in a cylindrical drawing mold to test its potential application while changing the material, blank holder force, and drawing ratio. We also quantitatively determined that the flow of other sheet materials was quantified locally using a square drawing die and that the measured value was always smaller than the drawing depth due to the material elongation. Finally, we propose a field that can be used by attaching the sensor to the press mold. We hope that the consequent cost reduction will contribute to increasing global mold competitiveness.

• Journal of Astronomy and Space Sciences
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• v.24 no.1
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• pp.79-90
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• 2007

The AmonRa instrument, the primary payload of the international EARTHSHINE mission, is designed for measurement of deep space albedo from L1 halo orbit. We report the optical design, tolerance analysis and the optical performance of the breadborad AmonRa imaging channel instrument optimized for the mission science requirements. In particular, an advanced wavefront feedback process control technique was used for the instrumentation process including part fabrication, system alignment and integration. The measured performances for the complete breadboard system are the RMS 0.091 wave(test wavelength: 632.8 nm) in wavefront error, the ensquared energy of 61.7%($in\;14\;{\mu}m$) and the MTF of 35.3%(Nyquist frequency: $35.7\;mm^{-1}$) at the center field. These resulting optical system performances prove that the breadboard AmonRa instrument, as built, satisfies the science requirements of the EARTHSHINE mission.

• Journal of Distribution Science
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• v.12 no.2
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• pp.95-103
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• 2014

Purpose - Korea has a better geographical location than other nations in the Northeast Asian region. This means that Korea has an opportunity to become the center of international physical distribution in Northeast Asia. Korea should take advantage of this opportunity by exploring appropriate strategies to achieve this goal, assuming government willingness, with a view to capitalizing on the geographical advantage of the Korean peninsula and constructing a comprehensive physical distribution network system. If we prepare for this scenario, Korea could become the center of international physical distribution in Northeast Asia. Research design, data, and methodology - This study has the purpose of determining how shipping companies form partnerships with third-party logistics providers, and the relevant implications. The survey methods used were personal interview and a questionnaire distributed through e-mail, fax, mail, and telephone. A total of 600 questionnaires were distributed, out of which 285 were returned. Of the collected questionnaires, 10 were excluded because of insufficient content, leaving 275 to be used in the study as available valid samples. The data that was collected from these samples was analyzed using the data coating process and by employing a statistical package program. Results - Flexible policies, administration, and systems will be needed to create better business practices. In this dissertation, first and foremost, the results reveal that in order to become the center of Northeast Asian logistics, Korea must transition into a new paradigm based on the current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. Flexible policies, administration, and systems will be required to create better business practices. Domestic logistics corporations need to occupy a strategic logistics hub, create a logistics network, and activate value-added logistics business strategies by ensuring significant manpower and by building a logistics information system to strengthen their competitive edge, creating an improved system. Conclusions - In this dissertation, first and foremost, we point out that in order to become a center of North East Logistics, Korea should change to a new paradigm from the old one based on current economic and social systems that have stemmed from bureaucracy, inflexibility, chauvinism, and egalitarianism. More reasonable business laws, systems, and policies based on market-driven flexibility and transparency should be created. Moreover, social norms and rules should be reasonably established, to accomplish political and social security. Korea has to cultivate a culture of tolerance for foreign companies. This involves a change of paradigm for the development of the capital city and satellite cities. It will take a powerful task force or organization to plan and execute the vision that aims to meet these needs, accomplish the necessary goals, use the appropriate system effectively, and make Korea a key country in the field of Northeast Asian logistics.

• Journal of the Korean Society for Railway
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• v.10 no.6
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• pp.701-708
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• 2007

A tilting train, which was developed to run the curve section without reducing the speed and compromising the riding quality, can improve the speed so as to reduce the travel time, compared to the existing trains. Then the force generated by the train operation to the track is in proportion to train operation speed, which means the track shall bear the increased force as much as the increase in train operation speed. Particularly, wheel load and lateral wheel load generated by train operation and distributed to the rail tend to cause the track to suffer the strain and furthermore the severe disaster such as derailment. To deal with such problem and ensure the train will run safety and stably, the tolerance in wheel load change, lateral wheel load and derailment coefficient was determined for quantitative evaluation of the train operation stability. In this study, derailment coefficient of inner and outer rail at existing curve section of tilting train was determined to evaluate the curve radius, possibility of acceleration and the need of rail improvement, which was then compared with the existing traditional train and high speed train. Conducting the quantitative evaluation of dynamic wheel load and lateral wheel load of each train, which was based on field survey, derailment coefficient and static & dynamic wheel load change, which serve the evaluation criteria of train operation stability, were determined for comparison with the standards, thereby analyzing the stability of the tilting train.

• Korean Journal of Microbiology
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• v.48 no.2
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• pp.116-124
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• 2012

Identification was performed in March 2008 for the 76 Enterococcus strains isolated from the Han-river, which is used as water supply for Seoul citizens. The antibiotic susceptibility, antibiotic resistant structural analysis, trans-conjugation, pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST) were also carried out for the isolated strains. Among the isolated strains, 25 strains were E. casseliflavus, 4 strains were E. faecalis and 1 strain was E. hirae. Investigation of antibiotic susceptibility indicated that 15 strains demonstrated tolerance against vancomycin, and that 11 strains of E. faecium and 4 strains of E. casseliflavus were VRE. The vanA gene detection of the VRE strains revealed that 6 E. faecium strains were vancomycin-resistant Enterococcus faecium (VREF) possessing vanA. Analyses of transposon Tn1546 structure containing vanA demonstrated that Km36 and Km37 belonged to Tn1 type, Km20 and Km38 was Tn2 type, and Km39 and Km40 was Tn3 type. PFGE disclosed that among the 6 VREF strains, Km36 and Km37 exhibited equivalent subtype, while the rest 4 strains showed subtypes different to each other. MLST for the 6 VREF strains disclosed that 3 strains were ST78, while the rest 3 strains were ST18, ST192 and ST230, respectively. All these clonal complexes were derived from CC17 which has been isolated from clinical sources. 4 strains belonged to CC78, while the rest 2 strains were CC18 and CC192, respectively.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.102-102
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• 2014

The NISS (Near-infrared Imaging Spectrometer for Star formation history) onboard NEXTSat-1 is the near-infrared instrument onboard NEXTSat-1 which is being developed by KASI. The main scientific targets are nearby galaxies, galaxy clusters, star-forming regions and low background regions in order to study the cosmic star formation history in local and distant universe. After the Preliminary Design Review, we have fixed major specifications of the NISS. The off-axis optical design with 15cm apertureis optimized to obtain a wide field of view ($2deg.{\times}2deg.$), while minimizing the sensitivity loss. The opto-mechanical structure of the NISS was designed to be safe enough to endure in the launching condition as well as the space environment. The tolerance analysis was performed to cover the wide wavelength range from 0.95 to $3.8{\mu}m$ and to reduce the degradation of optical performance due to thermal variation at the target temperature, 200K. The $1k{\times}1k$ infrared sensor is operated in the dewar at 80K stage. We confirmed that the NISS can be cooled down to below 200K in the nominal orbit through a radiative cooling. Here, we report the preliminary design of the NISS.

• Archives of Craniofacial Surgery
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• v.13 no.2
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• pp.85-94
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• 2012

The world's first face transplantation was performed in France, in 2005. Since then, 21 cases of face transplantation have been performed. Face transplantation is one of the most prominent part of composite tissue allotransplantation (CTA) along with hand transplantation. Since these fields are not deal with life-saving organs, there are many arguments about immunosuppression therapy. Recent paradigm of face transplantation shows that surgical ranges are expanded from partial face transplantation to full face transplantation. Most immunosuppression protocols are triple therapy, which consists of tacrolimus (FK-506), mycophenolate mofetil and prednisolone. Anatomical researches, immunosuppression, and immunotolerance take great parts in the researches of CTA. The medical fields directly related to face transplantation are microsurgery, immunology, and transplantation. Nowadays, each field is performed widely. Therefore people, even medical teams think face transplantation could be easily realized, sooner or later. But there are lots of things that should be prepared for not only practice and immunosuppression therapy but also for the cooperation with relevant fields. That's the reason why only 21 cases of face transplantation have been done, while more than 70 cases of hand transplantation have been done in the past years. Especially in Korea, brain death patients are not enough even for organ transplantation and furthermore there are some troubles in taking part in the society of transplantation. Face transplantation has lots of problems concerning variable medical fields, administration, society, ethics, and laws. Therefore, for the realization of face transplantation in Korea, not only medical skills but also political powers are needed.