• Title/Summary/Keyword: soft mechanism

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Bioactive Marine Natural Products in Drug Development

  • Kim, Se-Kwon;Ravichandran, Y. Dominic;Kim, Moon-Moo;Jung, Won-Kyo
    • Journal of Marine Bioscience and Biotechnology
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    • v.2 no.4
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    • pp.209-223
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    • 2007
  • Nature is one of the most important sources of pharmacologically active compounds in the search for drugs against life threatening diseases. Even though plants and terrestrial microorganisms have played as an important source for the new drug candidates from nature, marine organisms such as tunicates, sponges, soft corals, sea horses, sea snakes, marine mollusks, seaweeds, nudibranches, sea slugs and marine microorganisms are increasingly attracting attention in recent years. Marine organisms also have the potential to develop into future drugs against important diseases, such as cancer, a range of bacterial and viral diseases, malaria, and inflammations. Even though the mechanism of action in the molecular level of most metabolites is still unclear, the mechanisms by which they interfere with the pathogenesis of a wide range of diseases have been reported. The knowledge of this is one of the key factors necessary to develop bioactive compounds into medicines. This is due to their structurally unique and pharmacologically active compounds. The potential pharmaceutical, medicinal and research applications of some of these compounds are discussed in hundreds of scientific papers, and are reviewed here.

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Centrifuge Model Experiments on Behaviour Characterisitc in Forced Replacement Method (강제치환 거동특성에 관한 원심모형실험)

  • Lee, Jong-Ho;Park, Byung-Soo;Jeong, Gil-Soo;Yoo, Nam-Jae
    • Journal of Industrial Technology
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    • v.23 no.A
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    • pp.131-137
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    • 2003
  • This thesis is results of centrifuge model experiments to investigate the behavior of replacement method in dredged and reclaimed ground. For experimental works, centrifuge model tests were carried out to investigate the behavior of replacement method in soft clay ground. Basic soil property tests were performed to find mechanical properties of clay soil sampled from the southern coast of Korea which was used for ground material in the centrifuge model tests. Reconstituted clay ground of model was prepared by applying preconsolidation pressure in 1g condition with specially built model container. Centrifuge model tests were carried out under the artificially accelerated gravitational level of 50g. Replacing material of leads having a certain degree of angularity was used and placed until the settlement of embankment of replacing material was reached to the equilibrium state. Vertical displacement of replacing material was monitored during tests. Depth and shape of replacement, especially the slope of penetrated replacing material and water contents of clay ground were measured after finishing tests. Model tests of investigating the stability of embankment after backfilling were also performed to simulate the behavior of the dike treated with replacement and backfilled with sandy material. As a result of centrifuge model test, the behavior of replacement, the mechanism of the replacing material being penetrated into clay ground and depth of replacement were evaluated.

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Three Dimensional Behavior or Square Footing and Bnlined Solt Ground Tunnel (정방형 기초와 Unlined Soft Ground터널의 3차원적 거동)

  • 유충식
    • Geotechnical Engineering
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    • v.10 no.3
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    • pp.97-110
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    • 1994
  • Interaction between an unlined tunnel may cause a serious stability both the tunnel and the overlying and unli Red tunnel interaction meta study on the three dimensional bets a three dimensional elasto plastic the program, a wide range of blur puter analysis such as stress distr menu and tunnel deformation were footing and unlined tunnel. The yes traces the ultimate bearing capacity only on the tunnel size and location revealed is that an unlined tunnel under a square footing is subjected to three dimensional stress pattern along the tunnel axis, and that the magnitudes of stresses in the foundation soil and around tunnel perimeter are considerably smaller when loaded with a square than with a strip footings and the difference varies with the location and the type of stress. It is also revealed that the footing failure mechanism varies with the degree of footing and tunnel interaction.

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A 3D analytical model for the probabilistic characteristics of self-healing model for concrete using spherical microcapsule

  • Zhu, Hehua;Zhou, Shuai;Yan, Zhiguo;Ju, Woody;Chen, Qing
    • Computers and Concrete
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    • v.15 no.1
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    • pp.37-54
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    • 2015
  • In general, cracks significantly deteriorate the in-situ performance of concrete members and structures, especially in urban metro tunnels that have been embedded in saturated soft soils. The microcapsule self-healing method is a newly developed healing method for repairing cracked concrete. To investigate the optimal microcapsule parameters that will have the best healing effect in concrete, a 3D analytical probability healing model is proposed; it is based on the microcapsule self-healing method's healing mechanism, and its purpose is to predict the healing efficiency and healing probability of given cracks. The proposed model comprehensively considers the radius and the volume fraction of microcapsules, the expected healing efficiency, the parameters of cracks, the broken ratio and the healing probability. Furthermore, a simplified probability healing model is proposed to facilitate the calculation. Then, a Monte Carlo test is conducted to verify the proposed 3D analytical probability healing model. Finally, the influences of microcapsules' parameters on the healing efficiency and the healing probability of the microcapsule self-healing method are examined in light of the proposed probability model.

A study of the radioprotection effect of guarana (Paullinia cupana) on the fetuses of ICR mice THE RADIATION PROTECTION EFFECTS OF GUARANA

  • Gu, Yeun-Hwa;Hasegawa, Takeo;Suzuki, Ikukatsu;Yamamoto, Youichi;Yoon, Yeog-Byung;Rhee, Soo-Yong
    • Journal of Radiation Protection and Research
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    • v.26 no.4
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    • pp.347-356
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    • 2001
  • Guarana, a tropical plant is found in powdered for in health food and is very popular soft drink in Brazil as an energy feaster with its high caffeine contents. We examined its radioprotection effects during organogenesis stages of ICR mice by malformations rate and cellular lead 8 the embryo by radiation and analyzed the mechanism of the radioprotection effects in the fetal of ICR mice. The results of this study showed that Guarana reduced clearly the embryonic death rate and teratogenesis rate by radiation. Its radioprotection effect inject be related with its radioprotection effect might be related with its antioxidant effect or free radical scavenger. We need to exposure the Guarana as a potential radioprotection agent. Therefore, we investigated about radiation effects by Guarana using to mice experiments in this paper.

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Study on the Electrochemical Characteristics of a EGaIn Liquid Metal Electrode for Supercapacitor Applications (수퍼커패시터 응용을 위한 EGaIn 액체 금속 전극의 전기화학 특성 연구)

  • SO, JU-HEE;KOO, HYUNG-JUN
    • Journal of Hydrogen and New Energy
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    • v.27 no.2
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    • pp.176-181
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    • 2016
  • Recent years, supercapacitors have been attracting a growing attention as an efficient energy storage, due to their long-lifetime, device reliability, simple device structure and operation mechanism and, most importantly, high power density. Along with the increasing interest in flexible/stretchable electronics, the supercapacitors with compatible mechanical properties have been also required. A eutectic gallium-indium (EGaIn) liquid metal could be a strong candidate as a soft electrode material of the supercapacitors because of its insulating surface oxide layer for electric double layer formation. Here, we report the electrochemical study on the charging/reaction process at the interface of EGaIn liquid metal and electrolyte. Numerical fitting of the charging current curves provides the capacitance of EGaIn/insulating layer/electrolyte (${\sim}38F/m^2$). This value is two orders of magnitude higher than a capacitance of a general metal electrode/electrolyte interface.

The Anatomy and Biomechanics of knee joint for orthopedic local taping (슬관절의 정형의학적 국소 테이핑을 위한 해부학과 생체역학에 관한 문헌적 고찰)

  • Lim, Hyun-Dai;Kim, Hye-Won;Kim, Yong-Kwon
    • Journal of Korean Physical Therapy Science
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    • v.9 no.4
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    • pp.177-184
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    • 2002
  • The knee joint is composed of 3 skeletons that is the femoral bone, the tibial bone, and the patella bone. The tibiofemoral pint and patellofemoral pint act with the meniscus, so these function that is maintain the stabilities by the surrounding soft tissue is complex. The protection mechanism(muscle tension) of the surrounding muscles for the joint disease(Arthritis) limits consistently the motion of the pint to decrease the internal pressure of the joint, and these muscle tension acts with abnormal function for the surrounding tissue and the joint, sometimes the contracture is developed, if the joint with disease is not recovery or treated within early time. So we worked out efficient orthopedic local taping for the patient who is complained of the knee pint pain using the literature investigation about the anatomical structure and the biomechanics of the knee pint for the muscle and the pint problem esp, the rotation of the tibia, the dislocation of the patella, and the motion of the meniscus that is developed due to tension of surrounding muscles of the knee pint. And application of the pint mobilization, the stretching, and the muscle strengthening exercise for the pint will become successful treatment for the joint disease.

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Ultra Low Field Sensor Using GMI Effect in NiFe/Cu Wires

  • Kollu, Pratap;Kim, Doung-Young;Kim, Cheol-Gi
    • Journal of Magnetics
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    • v.12 no.1
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    • pp.35-39
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    • 2007
  • A highly sensitive magnetic sensor using the Giant MagnetoImpedance effect has been developed. The sensor performance is studied and estimated. The sensor circuitry consists of a square wave generator (driving source), a sensing element in a form of composite wire of a 25 $\mu$m copper core electrodeposited with a thin layer of soft magnetic material ($Ni_{80}Fe_{20}$), and two amplifier stages for improving the gain, switching mechanism, scaler circuit, an AC power source driving the permeability of the magnetic coating layer of the sensing element into a dynamic state, and a signal pickup LC circuit formed by a pickup coil and an capacitor. Experimental studies on sensor have been carried out to investigate the key parameters in relation to the sensor sensitivity and resolution. The results showed that for high sensitivity and resolution, the frequency and magnitude of the ac driving current through the sensing element each has an optimum value, the resonance frequency of the signal pickup LC circuit should be equal to or twice as the driving frequency on the sensing element, and the anisotropy of the magnetic coating layer of the sensing wire element should be longitudinal.

Review of negative-pressure wound therapy (음압 창상 처치(Negative pressure wound therapy)에 대한 문헌적 고찰)

  • You, Ju Lee;Kang, Jae Kyoung
    • Journal of Medicine and Life Science
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    • v.15 no.2
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    • pp.56-61
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    • 2018
  • Advances in medical technology has enabled better management of complicated and chronic wounds. Negative-pressure wound therapy (NPWT) is a novel dressing technique that uses negative pressure to drain exudates and blood from wounds. NPWT increases local blood flow and promotes reduction of edema and wound healing and is suitable for a variety of wounds. It is associated with few adverse effects and shows excellent efficacy and cost-effectiveness. NPWT promotes rapid growth of granulation tissue and wound contraction; thus, it is more advantageous than general dressings as it reduces the size skin of grafts or flaps required for repair, and patients with chronic wounds can be treated as outpatients. We investigated the general usage and mechanism of NPWT, its clinical applications and adverse effects.

Inter-Process Correlation Model based Hybrid Framework for Fault Diagnosis in Wireless Sensor Networks

  • Zafar, Amna;Akbar, Ali Hammad;Akram, Beenish Ayesha
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.2
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    • pp.536-564
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    • 2019
  • Soft faults are inherent in wireless sensor networks (WSNs) due to external and internal errors. The failure of processes in a protocol stack are caused by errors on various layers. In this work, impact of errors and channel misbehavior on process execution is investigated to provide an error classification mechanism. Considering implementation of WSN protocol stack, inter-process correlations of stacked and peer layer processes are modeled. The proposed model is realized through local and global decision trees for fault diagnosis. A hybrid framework is proposed to implement local decision tree on sensor nodes and global decision tree on diagnostic cluster head. Local decision tree is employed to diagnose critical failures due to errors in stacked processes at node level. Global decision tree, diagnoses critical failures due to errors in peer layer processes at network level. The proposed model has been analyzed using fault tree analysis. The framework implementation has been done in Castalia. Simulation results validate the inter-process correlation model-based fault diagnosis. The hybrid framework distributes processing load on sensor nodes and diagnostic cluster head in a decentralized way, reducing communication overhead.