• Title/Summary/Keyword: counter force

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THREE-DIMENSIONAL CRYSTALLIZING ${\pi}$-BONDING , ${\pi}$-FAR INFRARED RAYS AND NEW SPACE ENERGY RESOURCE

  • Oh, Hung-Kuk
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1996.04a
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    • pp.73-87
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    • 1996
  • The outer-most electrons of metal atoms and the remining valence electrons of any molecular atoms make three dimensional crystallizing $\pi$-bondings. The electrons on the $\pi$-bonding orbital rotate clockwise or counter-clockwise and they then make electro-magnetic waves between atoms on the orbital because electron move between plus charged ions. The three dimensional crystallizing $\pi$-bonding orbitals are quantum-mechanically modeled by a cyclic Kronig-Penny Model and energy band structures are analyzed with their potential barrier thickness. The waves generated between plus charged ions are the particular $\pi$-far infrared rays, which have dual properties between material and electro-magnetic waves and can be measured not by modern electro-magnetic tester but biosensor such as finger's force tester. Because the $\pi$-rays can be modulated with electro-magnetic waves it can be applied for harmful electro-magnetic wave killers. Because the $\pi$-rays make new three dimensional crystallizing $\pi$-bonding orbitals in the material the food and drink can be transformed into a helpful physical constitutional property for human health. Distinction between crystalline and amorphous metals is possible because very strong crystalline $\pi$-bonding orbitals can not easily be transformed into another. The $\pi$-rays can also be applied for biofunctional diagnostics and therapy. Gravitational field is one of the electro-magnetic fields. And also magnetic field and gravitational force field make charge's movement. ($\times$ = q, : magnetic field, : force field, q: plus charge, : velocity field)

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A Design Of Active Vibration Control System For Precise Maglev Stage (초정밀 자기부상 스테이지용 능동진동제어시스템 설계)

  • Lee, Joo-Hoon;Kim, Yong-Joo;Son, Sung-Wan;Lee, Hong-Ki;Lee, Se-Han;Choi, Young-Kiu
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2004.11a
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    • pp.121-124
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    • 2004
  • In this paper, we address an active vibration control system, which suppresses the vibration engaged by magnetically levitated stage. The stage system consists of a levitating platen with four permanent magnetic linear synchronous motors in parallel. Each motor generates vertical force fer suspension against gravity and propulsion force horizontally as well. This stage can generate six degrees of freedom motion via the vertical and horizontal forces. In the stage system, which represents the settling-time critical system. the motion of the platen vibrates mechanically. We designed an active vibration control system for suppressing vibration due to the stage moving. The command feedforward with inertial feedback algorithm is used fer solving stage system's critical problems. The components of the active vibration control system are accelerometers for detecting stage table's vibrations, a digital controller with high precise signal converters, and electromagnetic actuators.

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Robotics for Advanced Therapeutic Colonoscopy

  • Wong, Jennie YY;Ho, Khek Yu
    • Clinical Endoscopy
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    • v.51 no.6
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    • pp.552-557
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    • 2018
  • Although colonoscopy was originally a diagnostic imaging procedure, it has now expanded to include an increasing range of therapeutic interventions. These procedures require precise maneuvers of instruments, execution of force, efficient transmission of force from the operator to the point of application, and sufficient dexterity in the mobilization of endoscopic surgical instruments. The conventional endoscope is not designed to support technically demanding endoscopic procedures. In case of colonoscopy, the tortuous anatomy of the colon makes inserting, moving, and orientating the endoscope difficult. Exerting excessive pressure can cause looping of the endoscope, pain to the patient, and even perforation of the colon. To mitigate the technical constraints, numerous technically enhanced systems have been developed to enable better control of instruments and precise delivery of force in the execution of surgical tasks such as apposing, grasping, traction, counter-traction, and cutting of tissues. Among the recent developments are highly dexterous robotic master and slave systems, computer-assisted or robotically enhanced conventional endoscopes, and autonomously driven locomotion devices that can effortlessly traverse the colon. Developments in endoscopic instrumentations have overcome technical barriers and opened new horizons for further advancements in therapeutic interventions. This review describes examples of some of these systems in the context of their applications to advanced therapeutic colonoscopy.

Behavior of the Edge Flame on Flame Extinction in Buoyancy minimized Methane-Air Non-premixed Counter Triple Co-flow Flames (부력을 최소화한 대향류 삼축 메탄-공기 비예혼합 화염 소화에서 에지화염의 거동)

  • Park, Jin Wook;Park, Jeong;Yun, Jin-Han;Keel, Sang-In
    • 한국연소학회:학술대회논문집
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    • 2014.11a
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    • pp.81-84
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    • 2014
  • A Experimental study on flame extinction behavior was investigated using He curtain flow with counter triple co-flow burner. Buoyancy force was suppressed up to a microgravity level of $10^{-2}-10^{-3}g$ by using He curtain flow. The stability maps were provided with a functional dependency of diluent mole fraction and global strain rate to clarify the differences in flame extinction behavior. The flame extinction curves had C-shapes at various global strain rates. The oscillation and extinction modes were different each other in terms of the global strain rate, and the flames extinction modes could be classified into five modes such as (I) and (II): an extinction through the shrinkage of the outmost edge flame forward the flame center after self-excitation and without self-excitation, respectively, (III): an extinction through rapid advancement of a flame hole while the outmost edge flame is stationary, (IV): self-excitation occurs in the outermost edge flame and the center edge flame and then a donut shaped flame is formed and/or the flame is entirely extinguished, (V): shrinkage of the outermost edge flame without self-excitation followed by shrinkage or survival of the center flame. These oscillation and extinction modes could be identified well to the behavior of edge flame. The result also showed that the edge flame was influenced significantly by the conductive heat losses to the flame center or ambient He curtain flow.

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China's Naval Strengthening and US Navy's Counter-Forces (중국의 해군력 증강과 미국 해군의 대응전략 -중국 해군의 반접근/지역거부(A2/AD)전략 수행능력을 중심으로-)

  • Kim, Duk-ki
    • Strategy21
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    • s.42
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    • pp.196-223
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    • 2017
  • The aim of this paper is to analyze China's naval strengthening and threat reflected in submarines, aircraft, destroyers and missile capabilities and US Navy's counter-forces. China is strengthening its naval forces in accordance with its three-step naval force build-up plan, and the introduction of Russian destroyers and submarines is a foothold for China's naval enforcement. The Chinese Navy also converted the concept of the First-Second Island Chain Defense, which it had already maintained, to the concept of maritime layer defense. Currently, the Chinese Navy maintains the concept of a Three-Maritime Layer Defense which includes the South China Sea, where artificial islands are being built by China, in the First Layer Defense and the East China Sea in the Third Layer Defense. Along with the advancement of Chinese Navy's submarines, surface vessels and aircraft's operational capabilities, ballistic and cruise missile capabilities become a major threat to the US Navy. If a crisis occurs in the East China Sea or in the Taiwan Waters, the US Navy will face more difficulties in employing the Carrier Strike Group to manage the crisis. Meanwhile, if a crisis occurs on the Korean Peninsula, it will be a burden to dispatch Carrier Strike GroupS to the East and West Seas of the Korean Peninsula. For the stable future, the US Navy should develop a strategy to respond more effectively to the Chinese Navy, which is challenging new maritime supremacy in East Asia.

Study of a vibrating propulsion system for marine vessels: Evaluation of the efficiency for a boat 13 m long

  • Muscia, Roberto
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.10 no.2
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    • pp.201-211
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    • 2018
  • This paper illustrates recent advancements relative to a non-conventional propulsion system for boats and is based on two previous papers of the author presented at a conference (see Muscia, 2015a,b). The system does not consider propellers and utilizes the vibration generated by two or more pairs of counter rotating masses. The resultant of the centrifugal forces applies an alternate thrust to the hull that oscillates forward and backward along the longitudinal axis of the boat. The different hydrodynamic drag forces that oppose to the oscillation produce a prevalently forward motion of the vessel. The vibration that causes the motion can be suitably defined to maximize the forward displacement and the efficiency propulsion of the system. This result is obtained by using elliptical gears to rotate the counter rotating masses. The computation of the propulsion efficiency is based on a suitable physical mathematical model. Correlations between numerical experiments on models and possible full scale application are discussed. Some remarks in relation to practical applications and critical issues of the propulsive solution are illustrated. The results have been obtained with reference to a CAD model of a real boat already manufactured whose length is approximately equal to 13 m.

Directions of ROK Navy's Future Developments in Responding to Asymmetric Threats posed by North Korea (북한 비대칭 위협 대응한 한국 해군전력 발전방향)

  • Boo, Hyeong-wook
    • Strategy21
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    • s.40
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    • pp.190-215
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    • 2016
  • As North Korea's asymmetric threats are growing, there have been numerous discussions to find out effective counter-measures and many official plans and procurements efforts have been established. However, discussions on ROK Navy's roles in countering North Korea's asymmetric threats have been taken place very limitedly. Decision makers and military planners put enormous efforts in getting counter-measures, however, most of the options on the table are systems of Army and Air Force. This is true if one looks at components of Kill-Chain, KAMD, and KMPR. With worsening security environment of the Korean peninsula, it has been said by many commentators that ROK Navy needs to consider expanding its roles in countering against North Korea's asymmetric military threats. They asked ROK Navy to go beyond the mind-set that has confined Navy's roles in deterring North Korean naval threats. That is, ROK Navy should fight 'from the sea' as well as fight 'on the sea.' If ROK Navy begins to think about fight 'from the sea,' there would be many possibilities for the Navy to be a part of countering North Korea's asymmetric military threats. In order to pursue proactive roles in countering North Korea's asymmetric threat, ROK Navy needs to consider various options. Massive missile forces, nuclear-propelled submarines, naval special forces may be some of them. With those measures, ROK Navy would launch massive and decisive attacks from the sea without risking survivability of our forces. Considering North Korean Navy's weakness, it is very probable that sea would be safer place than ground or sky. Expanding ROK Navy's roles and being a proactive deterrent forces against North Korean asymmetric threats would provide very reliable counter-measures to South Korean military. Thus, military planners should think how to take the best advantage of expanded ROK Navy's roles and capabilities against North Korean asymmetric threats.

Molecular Interactions of Soaked Nonionic Dye in Ionomer Films (아이오노머 필름에 흡수된 비이온계 염료의 분자간 상호작용에 관한 연구)

  • ;;;;;;Forrest A. Landis;Robert B. Moore
    • Polymer(Korea)
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    • v.25 no.5
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    • pp.671-678
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    • 2001
  • Sodium and zinc salts of poly(ethyaene-co-methacrylic acid) ionomers consist of three phases, i.e. ionic aggregates, amorphous, and crystalline phases. Dye molecules after soaked from the methanol solution are located near the amorphous phase or ionic aggregates within ionomer films. Depending on the location of the molecules in the ionomer film, they are under influence of dispersion forces (ethylene parts), polar forces (acid parts). and ionic dipole (ionic aggregates) interactions. The UV/Vis absorption peak of Nile Red under the dispersion force is found at near 500 nm, for the dye under the polar force effect 525 nm, and 550 and 610 nm for the dyes under $Na^+$ and $Zn^{2+}$ ionization effects, respectively. Since the divalent $Zn^{2+}$ ion has larger ionic dipole than the monovalent $Na^+$ ion, the larger red-shift of the absorption band due to the ionic dipole interaction is observed for $Zn^{2+}$ counter ion.

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Validity of Ground Reaction Forces during Gait and Sit-to-Stand using the Nintendo Wii Balance Board in Healthy Subjects (Wii Balance Board를 이용한 Sit-to-Stand와 보행시 지면반발력의 타당도 분석)

  • Jeong, Yu-Jin;Park, Dae-Sung
    • Journal of the Korean Society of Physical Medicine
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    • v.11 no.4
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    • pp.85-92
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    • 2016
  • PURPOSE: A good, valid, and feasible tool for evaluating sit to stand (STS) is needed to help clinicians quantify the STS ability of stroke patients and people with balance disorders. The purpose of this study was to evaluate the concurrent validity of the Nintendo Wii Balance Board (WBB) and a force plate during STS and gait. METHODS: Seventeen healthy adults performed five trials of STS and gait on the WBB placed on the force plate. The force plate and the WBB were compared in regard to center of pressure (COP) and ground reaction force (GRF) data that were collected simultaneously. The variables used for analysis were time (s), integral summation (%), COP path length (mm), COP x range, and COP y range, all of which were measured for both tasks. Counter (%), peak (%), and rebound (%) were analyzed for STS, and $1^{st}$ peak (%), min peak (%), and 2nd peak (%) were analyzed for gait. The concurrent validity was analyzed using an intraclass correlation coefficient (ICC) and a standard error of measurement (SEM) with a 95% confidence interval. RESULTS: The concurrent validity of the WBB for STS ranged from fair to good (ICC=.701~.994, SEM=.029~3.815). The concurrent validity for gait was good (ICC=.869 ~.989, SEM=.007~2.052) aside from path length and x and y ranges of COP (ICC=-.150~.371, SEM=3.635~4.142). CONCLUSION: The GRF of the WBB has a good validity for STS and gait analysis. The WBB is remarkably portable, easy to use, and convenient for clinically assessing STS and gait.

A Study on the Counter-Measures for International Events through the Case Studies and Its Implications for Counter-Terrorism Policy (국제 행사에 대한 테러대응 사례분석과 정책적 함의)

  • Park, Dong-Kyun;Shin, Ik-Chu
    • Korean Security Journal
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    • no.14
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    • pp.161-179
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    • 2007
  • The numerous definition of terrorism is viewed as the use of force or violence by individual or group that is directed toward civilian populations and intended to instill fear as a means of coercing individuals or groups to change their political or social positions. Recently, the paradigm of terror has been developed as new terrorism motivated by 9. 11 terror in 2001. In these contexts, this study analyzed the case study of recent counter-terrorism of international events and suggested the policy implications. This study is split into four chapters. Chapter I is the introduction part. Chapter II introduces the reader to new terrorism theory, and Chapter III deals with the case study of the international counter-terrorism policy around the world, Chapter IV deals with the policy implications of the case study. The greater the political, economical and social advantages opening large international ceremonies, the larger the probability of being targets for terrorists and criminals. As terrorism is one of the important issue, the security problems at international ceremonies in Korea, rising country as political essence in Asian-Pacific region, become very important. With experienced know-hows against terror and preparations for security, local and central governments must promote the private security companies filling up vacancies of police and official security system and develop international ceremonies, rising high valuable industries in 21st century, with diplomatic efforts. International major events is the largest event related events with politics, economy, culture, and such large-scale events should be a comprehensive counterplan in the light of safety check for the location of a hazard and safety check of facilities in and out, attendance on athlete and visitor and escort of VIPs.

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