• Journal of Microbiology and Biotechnology
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• v.34 no.4
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• pp.747-756
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• 2024

Chronic gut inflammation promotes the development of metabolic diseases such as obesity. There is growing evidence which suggests that dysbiosis in gut microbiota and metabolites disrupt the integrity of the intestinal barrier and significantly impact the level of inflammation in various tissues, including the liver and adipose tissues. Moreover, dietary sources are connected to the development of leaky gut syndrome through their interaction with the gut microbiota. This review examines the effects of these factors on intestinal microorganisms and the communication pathways between the gut-liver and gut-brain axis. The consumption of diets rich in fats and carbohydrates has been found to weaken the adherence of tight junction proteins in the gastrointestinal tract. Consequently, this allows endotoxins, such as lipopolysaccharides produced by detrimental bacteria, to permeate through portal veins, leading to metabolic endotoxemia and alterations in the gut microbiome composition with reduced production of metabolites, such as short-chain fatty acids. However, the precise correlation between gut microbiota and alternative sweeteners remains uncertain, necessitating further investigation. This study highlights the significance of exploring the impact of diet on gut microbiota and the underlying mechanisms in the gut-liver and gut-brain axis. Nevertheless, limited research on the gut-liver axis poses challenges in comprehending the intricate connections between diet and the gut-brain axis. This underscores the need for comprehensive studies to elucidate the intricate gut-brain mechanisms underlying intestinal health and microbiota.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.7
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• pp.632-637
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• 2012

This paper introduces a simple and efficient calibration method for three-axis accelerometers and three-axis gyroscopes using three-axis motion rate table. Usually, the performance of low cost MEMS-based inertial sensors is affected by scale and bias errors significantly. The calibration of these errors is a bothersome problem, but the previous calibration methods cannot propose simple and efficient method to calibrate the errors of three-axis inertial sensors. This paper introduces a new simple and efficient method for the calibration of accelerometer and gyroscope. By using a three-axis motion rate table, this method can calibrate the accelerometer and gyroscope simultaneously and simply. Experimental results confirm the performance of the proposed method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.1 s.173
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• pp.182-189
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• 2000

This paper presents the real time control method of 5-axis NC machine for high precision and productivity based on the curvature theory, of a ruled surface. The trajectory, of NC machine is described by, way of a ruled surface generated by the points on part surface and tool axis direction vector. The curvature theory, of a ruled surface is then applied to deter-mine the motion parameters of the 5-axis machine for control. The controller computes position, orientation, and differential motion parameters of the tool in each sampling period. The real-time approach produces smoother surfaces and requires substantially less machining time compared to conventional off-line approaches. The propose real-time control method based of the curvature theory of a ruled surface may give new methodology of precision 5-axis machine control.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.155-160
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• 2002

Recently, the development of aerospace and automobile industries has brought new technological challenges, rebated to the growing complexity of products and the new geometry of the models. High speed milling with a 5-Axis milling machine has been widely used fur 3D sculptured surface parts. When turbine blades are machined by a 5-axis milling, their thin and cantilever shape causes vibrations, deflections and twists. Therefore, the surface roughness and the waviness of the workpiece are not good. In this paper, the effects of cutter orientation and the lead/tilt angle used to machine turbine blades with a 5-axis high speed ball end-milling were investigated to improve geometric accuracy and surface integrity. The experiments were performed using a lead/tilt angle of 15$^{\circ}$ to the workpiece with four cutter directions such as horizontal outward, horizontal inward, vertical outward, and vortical inward directions. Workpiece deflection, surface roughness and the machined surface were all measured with various cutter orientations such as cutting directions, and lead/tilt angle. The results show that the best cutting strategy for machining turbine blades with a 5-axis milling is horizontal inward direction with a tilt angle.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.3
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• pp.61-67
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• 2001

The finishing process for die is an important process because it has influence on final quality of products. Recently s study on development of 5-axis die automated finishing machine has been progressed. But die must be moved from the cutting machine to the die automated finishing machine. So manufacturing cost and time increase and machining error occurs by transfer. So, in this study, a 3-axis machining center was applied to die finishing. Because cutting tool can be changed to finishing tool by ATC, both of cutting and finishing process are possible on the machine. However, this application results in the decrease of finishing for the improvement of form accuracy. So this study focused on the generation of finishing tool path suitable to 3-axis die finishing for the improvement of form accuracy. The form accuracy evaluation is performed by the measurement of removal depth using a stylus profilometer. From the result, it is confirmed that form accuracy was improved less than 2$\mu$m of removal depth error.

• Development and Reproduction
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• v.23 no.4
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• pp.345-353
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• 2019

Higher thermal exposure can influence the blood cell morphology and count. Hence, based on the previous results (Rahman et al., 2019), the present study evaluated the morphometric indices of erythrocytes and their nucleus under different water temperatures (25℃, 28℃, 31℃, and 34℃) to investigate their use as an indicator of thermal stress in red spotted grouper, Epinephelus akaara. 180 healthy specimens of E. akaara were exposed to four temperature conditions (25℃ as control, 28℃, 31℃, and 34℃) for 42 days, following 2 weeks of acclimation at 25℃. Erythrocyte major axis (EL), erythrocyte minor axis (EW), nucleus major axis (NL), and nucleus minor axis (NW) were examined from the blood smears on each sampling day (i.e., 2, 7, and 42 days of thermal exposure). EL and NL were significantly decreased, whereas EW and NW were increased at higher water temperature (31℃ and 34℃). The major-minor axis proportions of erythrocytes and their nucleus (EL/EW; NL/NW) were decreased with increasing water temperature (31℃ and 34℃). The strong relationships were observed among the morphometric indices of erythrocytes and their nucleus, especially in EL vs. NL and EW vs. NW. This study reveals that elevated water temperature (31℃ and 34℃) can influence the major and minor axis morphometry of erythrocytes and their nucleus in red spotted grouper. These indices may be used as stress indicators to monitor the health status of E. akaara and probably for other fish species.

• IE interfaces
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• v.12 no.1
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• pp.68-78
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• 1999

A noncircular cutting such as a piston cutting has depended on the copy-machining because of its complex shape. But the copy-machining needs a master model and brings about a low quality of the piston caused by being worn out of the master model. And the lower cutting speed reduces the productivity. In this paper, for solving these problems, a specialized software system and its subsequent procedure are presented. The shape of a piston consists of an oval, an offset, recesses, and eccentricities. The paper describes these shapes as a consistent equation that is a function of the rotational angle and the position of longitudinal direction(Z-axis). It is simple to define the characteristic geometry of a piston and to generate a tool path for CNC machining. This paper proposes the a proper structure of a 4-axes CNC(Computerized Numerical Control) lathe for machining the piston. As well as X-axis and Z-axis, are attached to the machine a C-axis for rotation and a Y-axis for higher speedy prismatic motion parallel to X-axis.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.540-545
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• 2016

Many golf balls have wrong rotation axis owing to bad production and scratch. A flying golf ball makes sliced or curved motion mainly to owing the wrong rotation axis of golf ball. Dimples of golf ball make a golf ball higher and more straight flying. When we hit a golf ball by driver or iron club, the dimpled ball flies straight and rotates as well. While the ball flying, the rotating axis of the ball convergence. And this makes the ball motion curved. If we hit a golf ball in direction of the rotation axis, the flying ball makes straight motion. In this paper, we develop a control system to detect convergence axis and time of flying golf ball based on vision system. To show validity of the developed system, We experimented several case for dimpled golf balls.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.3
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• pp.334-343
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• 2018

The purpose of this study was to investigate the cause of eruption disturbance in the maxillary central incisor and establish the effective treatment plan by analyzing the vertical distance, angulation of long axis and root development of the tooth with eruption disturbance using the cone-beam CT. The average age of 134 patients diagnosed with unilaterally impacted maxillary central incisor was 7.9 years old and the male was 2.1 times higher than the female. The most common cause of eruption disorder was physical obstruction, especially mesiodens and odontoma. Of the teeth with unilateral eruption disorder, 78 cases erupted spontaneously and 56 cases erupted non-spontaneously after removal of physical obstruction. The possibility of spontaneous or non-spontaneous eruption in the unilaterally impacted maxillary central incisor depended on several factors, such as vertical distance, angulation of long axis and root development of unerupted tooth. The spontaneous eruption of the impacted maxillary cental incisor was most frequent at the angulation of long axis of 50 to 90 degrees, which is similar to the angulation of long axis of the normally erupted maxillary central incisor. In addition, the spontaneous eruption period of impacted maxillary central incisor was more influenced by the vertical distance than the angulation of long axis and the root development. Most of the teeth that showed non-spontaneous eruption had orthodontic traction, and these teeth were usually erupted within about 12 months. The period treated with orthodontic traction was no statistical significance with the vertical distance, the angulation of long axis, and the root development. This study will provide information on the cause of unilaterally impacted maxillary cental incisor and help to establish the future treatment plan.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.3
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• pp.253-259
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• 2014

There has been a need for replacing human labors with a robot in such dangerous and hard jobs of various construction sites. For that reason, many researches have been made about the high quality robot, which performs its duty instead of human labors. This study is about auto surveying system development based on VRS-GPS which enables autodriving in dangerous areas where it's difficult for humans to measure directly. This study is about the auto-surveying system development, based on VRS-GPS, which enables auto-drive in dangerous areas, whereas difficult for humans to measure directly. The GPS is made with GRXI and SHC250 controllers of the SOKKIA company. The auto surveying system is composed of DPS module, geomagnetism sensor, bluetooth, gimbals, IMU, etc to automatic drive via enter into a route of position. The developed auto surveying system has installed the carmeras for front and vertical axis as well as systems to grasp situation of surveying with smartphone in real time. The result from analysed RMSE of auto surveying system and VRS-GPS surveying is 0.0169m of X-axis and 0.0246m of Y-axis.