• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.1
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• pp.43-51
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• 2002

The cloning and expression of $\beta-glucosidase$ II, encoded by the gene ${\beta}glu2$, from thermotolerant yeast Pichia etchellsii into Escherichia coli is described. Cloning of the 7.3 kb BamHI/SalI yeast insert containing ${\beta}glu2$ in pUC18, which allowed for reverse orientation of the insert, resulted in better enzyme expression. Transformation of this plasmid into E. coli JM109 resulted in accumulation of the enzyme in periplasmic space. At $50^{\circ}C$, the highest hydrolytic activity of 1686 IU/g protein was obtained on sophorose. Batch and fed-batch techniques were employed for enzyme production in a 14 L bioreactor. Exponential feeding rates were determined from mass balance equations and these were employed to control specific growth rate and in turn maximize cell growth and enzyme production. Media optimization coupled with this strategy resulted in increased enzyme units of 1.2 kU/L at a stabilized growth rate of $0.14\;h^{-l}$. Increased enzyme production in bioreactor was accompanied by formation of inclusion bodies.

• Journal of Microbiology and Biotechnology
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• v.28 no.6
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• pp.931-937
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• 2018

Glycosyltransferases (GTs) from microbes are an emerging and rich source for efficient glycol-transformation of natural/unnatural compounds. Here, we probed the catalytic capability and substrate promiscuity of BmmGT1 from marine-derived Bacillus methylotrophicus B-9987. The regioselectivity of BmmGT1 on macrolactin A (1) was explored by optimization of the reaction conditions, in which a series of O-glycosylated macrolactins (1a-1e) were generated, including two new di/tri-O-glucosyl analogs (1b and 1e). Furthermore, BmmGT1 was able to catalyze the glycosylation of the thiol (S-) or amine (N-) sites of phenolic compounds (2 and 3), leading to the generation of N- (2a) or S-glycosides (3a and 3b). The present study demonstrates that BmmGT1 could serve as a potential enzyme tool for O-, N-, or S-glycosyl structural diversification of compounds for drug discovery.

• Smart Structures and Systems
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• v.26 no.3
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• pp.373-390
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• 2020

Hybrid simulation (HS) is a versatile tool for structural performance evaluation under dynamic loads. Although real structural responses are often multiple-directional owing to an eccentric mass/stiffness of the structure and/or excitations not along structural major axes, few HS in this field takes into account structural responses in multiple directions. Multi-directional loading is more challenging than uni-directional loading as there is a nonlinear transformation between actuator and specimen coordinate systems, increasing the difficulty of suppressing loading error. Moreover, redundant actuators may exist in multi-directional hybrid simulations of large-scale structures, which requires the loading strategy to contain ineffective loading of multiple actuators. To address these issues, lately a new strategy was conceived for accurate reproduction of desired displacements in bi-directional hybrid simulations (BHS), which is characterized in two features, i.e., iterative displacement command updating based on the Jacobian matrix considering nonlinear geometric relationships, and force-based control for compensating ineffective forces of redundant actuators. This paper performs performance validation and application of this new mixed loading strategy. In particular, virtual BHS considering linear and nonlinear specimen models, and the diversity of actuator properties were carried out. A validation test was implemented with a steel frame specimen. A real application of this strategy to BHS on a full-scale 2-story frame specimen was performed. Studies showed that this strategy exhibited excellent tracking performance for the measured displacements of the control point and remarkable compensation for ineffective forces of the redundant actuator. This strategy was demonstrated to be capable of accurately and effectively reproducing the desired displacements in large-scale BHS.

• Journal of KIISE:Software and Applications
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• v.32 no.1
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• pp.41-49
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• 2005

In this Paper, we Propose an automatic lung registration technique using local distance propagation for correcting the difference between two temporal images by a patient's movement in abdomen CT image obtained from the same patient to be taken at different time. The proposed method is composed of three steps. First, lung boundaries of two temporal volumes are extracted, and optimal bounding volumes including a lung are initially registered. Second, 3D distance map is generated from lung boundaries in the initially taken volume data by local distance propagation. Third, two images are registered where the distance between two surfaces is minimized by selective distance measure. In the experiment, we evaluate a speed and robustness using three patients' data by comparing chamfer-matching registration. Our proposed method shows that two volumes can be registered at optimal location rapidly. and robustly using selective distance measure on locally propagated 3D distance map.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.3
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• pp.55-70
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• 2016

The most critical research issue in MANET environment is on supporting reliable communication between various devices. Various Multi-Hop Routing Protocol studies have proceeded. However, some problems you might have found when you use the existing link state routing technique are that it increases Control Message Overhead and it is unstable when node moves in CR circumstance which has transformation of using channel and MIMC circumstance which uses a number of interfaces. This essay offers a technique which is based on On-Demand Hello and the other technique which used Broadcast Interface of optimization as a solution to decrease Control Message Overhead. Also it proposes Quick Route Restoration technique which is utilized by GPS and MPR Selection technique which consider mobility as a solution of stable communication when node moves. Those offered Routing Protocol and OPNET based simulator result will be expected to be an excellent comparison in related research fields.

• Journal of the Institute of Convergence Signal Processing
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• v.21 no.4
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• pp.183-194
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• 2020

Recently, the number of hip dysplasia (DDH) that occurs during infant and child growth has been increasing. DDH should be detected and treated as early as possible because it hinders infant growth and causes many other side effects In this study, two modelling techniques were used for multiple training techniques. Based on the results after the first transformation, the training was designed to be possible even with a small amount of data. The vertical flip, rotation, width and height shift functions were used to improve the efficiency of the model. Adam optimization was applied for parameter learning with the learning parameter initially set at 2.0 x 10e-4. Training was stopped when the validation loss was at the minimum. respectively A novel image overlay system using 3D laser scanner and a non-rigid registration method is implemented and its accuracy is evaluated. By using the proposed system, we successfully related the preoperative images with an open organ in the operating room

• Food Science of Animal Resources
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• v.43 no.3
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• pp.383-401
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• 2023

Camel milk has a significant and pivotal role in the diet of people residing in semi-arid and arid regions. Ever since ancient times, marketing of camel milk has remained insignificant due to nonexistence of processing amenities in the camel nurturing areas, hence the utilization of unprocessed camel milk has continuously remained limited at family level by the nomads. Due to the superior medicinal values and health promoting effects, incredible growth in the demand of camel milk and dairy products have been noticed all over the world during last two decades. Such emergence has led dairy industry to provide diversified camel dairy products to the consumers with superior nutritional and functional qualities. In contrast to bovine, very few food products derived from camel milk are available in the present market. With the advancements in food processing interventions, a wide range of dairy and non-dairy products could be obtained from camel milk, including milk powder, cheese, yogurt, ice cream, and even chocolate. In some regions, camel milk is used for traditional dishes such as fermented milk, camel milk tea, or as a base for soups and stews. Current review highlights the processing opportunities regarding the transformation of camel milk into various dairy products via decreasing the inherent functionality that could be achieved by optimization of processing conditions and alteration of chemical composition by using fortification method. Additionally, future research directions could be devised to improve the product quality.

• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.4
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• pp.641-648
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• 2023

Recently, the rapid growth of artificial intelligence among the 4th industrial revolution has progressed based on the performance improvement of semiconductor, and circuit integration. According to transistors, which help operation of internal electronic devices and equipment that have been progressed to be more complicated and miniaturized, the control of heat generation and improvement of heat dissipation efficiency have emerged as new performance indicators. The DUT(Device Under Test) Shell is equipment which detects malfunction transistor by evaluating the durability of transistor through heat dissipation in a state where the power is cut off at an arbitrary heating point applying the rating current to inspect the transistor. Since the DUT shell can test more transistor at the same time according to the heat dissipation structure inside the equipment, the heat dissipation efficiency has a direct relationship with the malfunction transistor detection efficiency. Thus, in this paper, we propose various method for PCB configuration structure to optimize heat dissipation of DUT shell and we also propose various transformation and thermal analysis of optimal DUT shell using computational fluid dynamics.

• Journal of the Korean GEO-environmental Society
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• v.24 no.1
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• pp.51-60
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• 2023

Unlike the vertical drilling in the directional drilling should be minimized torque and drag in the well trajectory that avoided problems such as drillstring transformation, casing wear and key-seating. These torque and drag magnitude is determined by variations such as the well trajectory geometry, drilling mud, drillstring type and kick-off point. Therefore, it is essential to consider these variations for designing directional well trajectory. In this study, it was selected well trajectory by the most common build-hold type well and calculated torque and drag on each section by Analytical friction model. Analysis indicates that torque and drag could be minimized by using high lubricity drilling mud, kick-off point appropriate according to the well geometry and possible minimize dogleg severity. The results of this study is useful to minimize torque and drag from directional well trajectory design.

• KIPS Transactions on Computer and Communication Systems
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• v.12 no.4
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• pp.135-142
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• 2023

Recently, many companies are using public cloud services or building their own data center because digital transformation is expanding. The software-defined storage is a key solution for storing data on the cloud platform and its use is expanding worldwide. Software-defined storage has the advantage of being able to virtualize and use all storage resources as a single storage device and supporting flexible scale-out. On the other hand, since the size of an object is variable, an imbalance occurs in the use of the disk and may cause a failure. In this study, a method of redistributing objects by optimizing disk weights based on storage state information was proposed to solve the imbalance problem of disk use, and the experimental results were presented. As a result of the experiment, it was confirmed that the maximum utilization rate of the disk decreased by 10% from 89% to 79%. Failures can be prevented, and more data can be stored by optimizing the use of disk.