• Journal of Korean Medical classics
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• v.19 no.2 s.33
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• pp.248-265
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• 2006

Impulse of ki refers to palpitation around the navel, it is mostly caused by impairment of yang due to erroneous sweating, deficiency of the spleen yang. Behcet's syndrome caused by prolonged damp-heat and pathogenic germs. Its symptoms are characterized by conjunctival congestion, blue canthus and ulceration of the oral cavity, restlessness all the time, etc. It is advisable to follow the therapeutic principles of clearing away heat and drying damp, detoxicating and sterilizing. Lily disease is one of the emotional disease. It caused by yin deficiency of the heart and lung, found in mental depression or convalescence after a critical disease. Its symptoms are characterized by restlessness, reticence, insomnia, failure to walk, poor appetite, a subjective hot or cold, bitter taste and dark urine. It is advisable to follow the therapeutic principle of nourishing yin to clear away heat. Cholera refers to the disease marked by sudden severe vomiting and diarrhea, and colic of the heart and the abdomen. It is mostly caused by deficiency of the ki in the middle-energizer, emotional stress, etc. It is characterized by such symptoms as sudden severe vomiting and diarrhea, restlessness, etc. It is advisable to follow the therapeutic principles of warming yang and removing toxic substances, and strengthening the spleen and stomach. Heat invasion of blood chamber due to affection of the exterior pathogens, pathogenic heat invading the blood in deficiency and fighting with the blood. Its symptoms are marked by fever, feeling of the fullness, etc. There are deficiency of blood, hot blood and stasis of blood. The different therapeutic treatment should be taken according to different types thereof.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.8
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• pp.1398-1408
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• 2003

Tensile and LCF(low cycle fatigue) tests were carried out in air at wide temperature range 20$^{\circ}C$-750$^{\circ}C$ and strain rates of 1${\times}$10$\^$-4//s-1${\times}$10$\^$-2/ to ascertain the influence of strain rate on tensile and LCF properties of prior cold worked 316L stainless steel, especially focused on the DSA(dynamic strain aging) regime. Dynamic strain aging induced the change of tensile properties such as strength and ductility in the temperature region 250$^{\circ}C$-600$^{\circ}C$ and this temperature region well coincided with the negative strain rate sensitivity regime. Cyclic stress response at all test conditions was characterized by the initial hardening during a few cycles, followed by gradual softening until final failure. Temperature and strain rate dependence on cyclic softening behavior appears to result from the change of the cyclic plastic deformation mechanism and DSA effect. The DSA regimes between tensile and LCF loading conditions in terms of the negative strain rate sensitivity were well consistent with each other. The drastic reduction in fatigue resistance at elevated temperature was observed, and it was attributed to the effects of oxidation, creep and dynamic strain aging or interactions among them. Especially, in the DSA regime, dynamic strain aging accelerated the reduction of fatigue resistance by enhancing crack initiation and propagation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.2
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• pp.250-263
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• 2001

The up and down speed of heddle frames that produce woven cloth by insertion of weft yarns between warp yarns has been increased recently much for productivity improvement, which induces higher inertial stresses and vibrations in the heddle frame. the heddle frame is required to reduce its mass because the heddle frame contributes the major portion of the stresses in the heddle frames during accelerating and decelerating. Conventional aluminum heddle frames have fatigue life of around 5 months at 550rpm due to their low fatigue flexural strength as well as low bending stiffness. In this work, since carbon/epoxy composite materials have high specific fatigue strength(S/p), high specific modulus(E/p), high damping capacity and sandwich construction results in lower deflections and higher buckling resistance, the sandwich structure composed of carbon/epoxy composite skins and polyurethane foam were employed for the high-speed heddle frame. The design map for the sandwich beams was accomplished to determine the optimum thickness and the stacking sequences for the heddle frames. Also the effects of the number of ribs on the stress of the heddle frame were investigated by FEM analyses. Finally, the high-speed heddle frames were manufactured with sandwich structures and the static and dynamic properties of the aluminum and the composite heddle frames were tested and compared with each other.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.359-371
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• 2017

This study qualitatively examined the lives of non-tenured, secondary school teachers who are preparing for the teachers' exam. Semi-structured, face-to-face interviews were conducted with ten teachers and the data were analyzed using the consensual qualitative research method. Most of the participants had chosen a contract-based teaching position, believing that it would meet their financial needs, provide them with the satisfaction of being a teacher and, more importantly, afford practical help with their exam preparation. In practice, however, they suffered from low self-esteem and identity confusion due to discrimination by the school administrators. Ironically, this unfair treatment strengthened the participants' commitment to studying for the exam, in order to acquire a stable and secure position in school. However, they experienced a lot of study-related stress, including a lack of study hours, heavy study load, multiple life roles, physical exhaustion, the difficulties caused by the vague exam guide, and anxiety due to previous failure in the exam. Based on the findings of this study, directions for future research are suggested.

• Herbal Formula Science
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• v.17 no.2
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• pp.123-132
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• 2009

Acetaminophen (AP) is widely used as an over-the-counter analgesic and antipyretic drug. AP-induced hepatotoxicity is a common consequence of AP overdose and may lead to acute liver failure. In this study, we investigated the liver damage in mice using single dose (300 mg/kg) of AP and the possible protective effects of administration (50-200 mg/kg body weight) of Joo-Juk on acetaminophen-induced liver damage in mice. The alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activities were determined in the plasma of mice. The effect of Joo-Juk on lipid peroxidation product thiobarbituric reacting substances (TBARS) and some antioxidant enzymes superoxide dismutase (SOD), catalase, d-aminolevulinate dehydratase ($\sigma$-ALA-D) activities, and gluthathione peroxidase (GPx), were also evaluated in the mouse liver homogenate. AP caused liver damage as evident by statistically significant increased in plasma activities of AST and ALT. There were statistically significant losses in the activities of SOD, catalase, $\sigma$-ALA-D, and GPx and an increase in TBARS in the liver of AP-treated group compared with the control group. However, Joo-Juk was able to counteract these effects. These results suggest that Joo-juk can act as hepato-protectant against AP toxicity and is a good candidate for further evaluation as an effective chemotherapeutic agent.

• Explosives and Blasting
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• v.37 no.4
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• pp.26-35
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• 2019

In designing a gravity-type anchorage of earth-anchored suspension bridge, the contact friction between a blasted rock mass and the concrete anchorage plays a key role in the stability of the entire anchorage. Therefore, it is vital to understand the shear behavior of the interface between the blasted rock mass and concrete. In this study, a portable 3D LiDAR scanner was utilized to scan the blasted bottom surfaces, and rock surface roughness was quantitatively analyzed from the scanned profiles to apply to 3D FEM modelling. In addition, based on the 3D FEM model, a three-dimensional dynamic fracture process analysis (DFPA-3D) technique was applied to study on the shear behavior of the interface between blasted rock and concrete through direct shear tests, which was analyzed under constant normal load (CNL). The effects of normal stress and the joint roughness on shear failure behavior are also analyzed.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.5
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• pp.1140-1146
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• 2008

One of the major side effects of cisplatin is nephrotoxicity, leading to acute renal failure. Recent study has suggested a role of hydroxyl radicals and p53 in renal cell injury by cisplatin. This study determined the possible involvement of oxidative stress in p53 activation. In rat mesangial cells, cisplatin treatment induced apoptosis and p53 activation. Pifithrin-$\alpha$, a pharmacological inhibitor of p53, suppressed cisplatin-induced apoptosis. Cisplatin also induced reactive oxidative species (ROS) generation. Of interest, cisplatin-induced apoptosis was prevented by N-acetyl-cysteine (NAC), a general antioxidant. NAC diminished p53 activation during cisplatin treatment. Puerariae Radix and Rehmanniae Radix Preparata with antioxidative activity were reduced the cisplatin-induced ROS generation, caspase-3 activity and p53 activation. In conclusion, ROS may contribute to p53 activation to initiate cisplatin-induced apoptosis in rat mesangial cells. In result, antioxidative effect of Puerariae Radix and Rehmanniae Radix Preparata prevented cisplatin-induced apoptosis through inhibition of p53 activation.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1591-1597
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• 2012

Adherend samples were made from unsaturated polyester and woven and mat glass fibers by the hand layup and vacuum methods. The mechanical properties of the adhesive, composite adherends, and terminal-joint and secondary-joint specimens were determined experimentally. Combinations of the experiment results and the bonding theory were used in this study. The maximum and average shear stresses were calculated based on the maximum tensile force and geometry parameters of the joint specimens. The results of the maximum and average shear stresses were compared and evaluated for six joints. The results showed that the grinding and grind/acetone joint had the highest strength among three types of terminal-joints. Similarly, the mat-mat and mat-woven joints had the highest strength among three types of secondary-joints with the same value. Conversely, no treatment and woven-woven bonding had very low strength. In each case, failure occurred always at two ends and then moved toward the middle area of the overlap length.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.3
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• pp.429-436
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• 2013

This study considers how the fatigue behavior and probabilistic properties of SAE1055 steel are related to its hardness level. SAE1055 steel was heat-treated using induction hardening. Five types of specimens were prepared (A: base material, B: through hardened material with HV390, C: through hardened material with HV510, D: through hardened material with HV700, and E: surface hardened material with HV700). Fatigue tests were performed under a stress ratio of R = -1 using a 4-point rotary bending fatigue tester. The fatigue behaviors were greatly influenced by the hardness, but the fatigue limit did not increase over a hardness of HV510. In addition, the effect of the hardness level on the failure mechanism was evaluated using a scanning electron microscope. The probabilistic properties of the fatigue life were investigated using a probabilistic S-N approach, and the effect of the hardness level on these properties was evaluated using a residue analysis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.3
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• pp.193-198
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• 2017

Alloy 617 is one of the primary candidate materials to be used in a very high temperature reactor (VHTR) system as an intermediate heat exchanger (IHX). To investigate the low cycle fatigue behavior of Alloy 617 weldments at a high temperature of $850^{\circ}C$, fully reversed strain-controlled fatigue tests were conducted with the total strain values ranging from 0.6~1.5％. The weldment specimens were machined using the weld pads fabricated with a single V-grove configuration by gas tungsten arc welding (GTAW) process. The fatigue life is reduced as the total strain range increases. For all testing conditions, the cyclic stress response behavior of the Alloy 617 weldments exhibited the initial cyclic strain hardening phenomenon during the initial small number of cycles. Furthermore, the overall fatigue cracking and the propagation or cracks showed a transgranular failure mode.