• Title/Summary/Keyword: Defence mechanism

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Pharmacological Evaluation of Proprietary Preparation from Bacterial Metabolites with Special Reference to its Immunomodulatory Actions

  • Auddy, Biswajit;Mitra, Susil K.;Mukherjee, Biswapati
    • Natural Product Sciences
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    • v.5 no.1
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    • pp.7-11
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    • 1999
  • A mixture of several bacterial metabolites $(Sterodin{\circledR})$ was used to study its effect on major immunocytes, in vivo and in vitro. This mixture of bacterial metabolites increased number of macrophages and neutrophils and their phagocytic activity in experimental animals for a transient period. BSA induced antibody production was found to be higher in the drug treated group. These results indicated that the bacterial metabolites probably acted through non-specific defence mechanism against invading organisms and the chance of reinfection was reduced.

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Reliability Prediction of a Pin Puller (핀풀러 신뢰도 예측)

  • Lee, Hyo-Nam;Jang, Seung-Gyo;Oh, Jong-Yun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.8
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    • pp.625-631
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    • 2013
  • Reliability of a pin puller was predicted by Monte Carlo simulation. The prediction method is based on the stress-strength interference model that failure occurs if the stress exceeds the strength. In this study, the strength is considered as the energy delivered by combustion of pyrotechnics to retreat the pin to a predetermined position, whereas the stress is regarded as the energy required to resist the pin movement. The former mainly depends on the amount of pyrotechnic charge and the latter is governed by several friction forces and the energy dissipation within locking mechanism. Both the variables of stress and strength were computed using an analytical performance model. The method presented here, not depending upon a large number of test item, can be applicable to predict the reliability of other kinds of pyrotechnic devices.

Study on Coupling Drive Mechanism for Multi-Axis Pintle Thrusters (다축 핀틀 추력기에 적용을 위한 구동장치 연동 메커니즘 방안연구)

  • Lee, Jaecheong;Huh, Hwanil;Lee, Hosung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.43 no.8
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    • pp.722-730
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    • 2015
  • Drive mechanism of multi-axis pintle thrusters for DCS(Divert Control System) was designed to meet the needs of minimizing the number of driving motors. In this study, preliminary model was designed in order to implement appropriate pressure control and thrust distribution. Based on the preliminary model study, the drive mechanism for DCS multi-axis pintle thrusters using piston was designed and evaluated by using AMESim software. Results show that three driving motors are enough to actuate four pintle thrusters.

A Study on Recoil Force Reduction Using a Low-recoil Direct Gun (저반동 전차포의 주퇴력 저감 연구)

  • Park, Jin-Saeng
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.5
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    • pp.125-130
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    • 2016
  • A low-recoil direct gun is useful in reducing the fire impulse generated by using a traditional shell. To apply a control equation to an AMESim Model, we have formulated a control equation for a recoil mechanism from the free object diagram. By modeling this equation, we have been able to compare the recoil distance and recoil force of a low-recoil direct gun. Here, we can analyze the recoil characteristics between traditional direct guns and low-recoil direct guns with perforated muzzle brakes. It is possible to mount a low-recoil direct gun with a perforated muzzle brake on a lightweight tracked vehicle by reducing its fire impulse.

A Study on MBTI Personality Type and Defense Mechanism of Nursing College Student (간호대학생의 MBTI 성격유형과 방어기제의 관계연구)

  • 황승숙;김은주
    • Journal of Korean Academy of Nursing
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    • v.32 no.4
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    • pp.447-458
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    • 2002
  • The primary purpose of this study is to provide a useful insight for developing effective teaching and student counseling methods by understanding the relationship between four preference patterns of MBTI personality types and EWHA defense mechanisms of nursing college students. Method: The data used in this research were collected administrating EWHA defense mechanism test and MBTI personality type instrument to 195 nursing students in the period of November 3 through September 16 in 2000. Collected data were analysed by pc-SPSS 10.0. Result: Three general conclusions were drawn from the study results: (1) in terms of personality type, 'Extraversion', 'Sensing', 'Thinking', and 'Judgement' types showed high frequency respectively; (2) in terms of defense mechanism, 'Identification' showed the highest score, and then 'suppression' scored next followed by 'Humor'. However, 'Acting out' showed the lowest average score, and then 'Projection' followed by 'Denial'; (3) Based on the relationship between defense mechanism and four MBTI preference patterns, it can be drawn that students with the preference of 'Extraversion' usually use defense mechanism of 'Altruism', 'Sublimation', 'Distortion', 'Controlling', and 'Humor'. In comparison, students with the preference of 'Introversion' often use the defence mechanism of 'Evasion' and 'Projection'. Conclusion: The study results can be utilized in both fields of education and counseling: (1) in the field of education, this study can provide a basis for developing a suitable teaching method for each personality types of nursing students; (2) for counseling practitioners, the results of this study provide the useful insights to understand nursing college students' communication skills, behavior patterns, and ability of coping with problems in the process of counseling.

An Attack Behavior Expressions for Web Attack Analysis and Composing Attack Database (웹 공격 분석 및 공격 데이터베이스 생성을 위한 효과적인 표현 방법에 관한 연구)

  • Lee, Chang-Hoon
    • Journal of Advanced Navigation Technology
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    • v.14 no.5
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    • pp.725-736
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    • 2010
  • Nowadays, followed the internet service contents increasing makes also increase attack case on the web system. Usually web attack use mixed many kinds of attack mechanism for successfully attack to the server system. These increasing of the kinds attack mechanism, however web attack defence mechanism is not follow the spread of the attack. Therefore, for the defends web application, web attack should be categorizing and analysing for the effective defense. In this paper, we analyze web attack specification evidence and behavior system that use for effective expressions what we proposed. Also, we generate web attack scenario, it is for using verification of our proposed expressions.

Congestion-Aware Handover in LTE Systems for Load Balancing in Transport Network

  • Marwat, Safdar Nawaz Khan;Meyer, Sven;Weerawardane, Thushara;Goerg, Carmelita
    • ETRI Journal
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    • v.36 no.5
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    • pp.761-771
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    • 2014
  • Long-Term Evolution employs a hard handover procedure. To reduce the interruption of data flow, downlink data is forwarded from the serving eNodeB (eNB) to the target eNB during handover. In cellular networks, unbalanced loads may lead to congestion in both the radio network and the backhaul network, resulting in bad end-to-end performance as well as causing unfairness among the users sharing the bottleneck link. This work focuses on congestion in the transport network. Handovers toward less loaded cells can help redistribute the load of the bottleneck link; such a mechanism is known as load balancing. The results show that the introduction of such a handover mechanism into the simulation environment positively influences the system performance. This is because terminals spend more time in the cell; hence, a better reception is offered. The utilization of load balancing can be used to further improve the performance of cellular systems that are experiencing congestion on a bottleneck link due to an uneven load.

A Study on the Blue Emitting SrAl12O19: Cex3+, Eu0.012+ Using Time-resolved Photoluminescence (SrAl12O19: Cex3+, Eu0.012+에서 시간분해 Photoluminescence을 이용한 청색발광에 관한 연구)

  • Kim, Gwang Chul;Choi, Jin Soo
    • Journal of the Semiconductor & Display Technology
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    • v.15 no.2
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    • pp.49-54
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    • 2016
  • $SrAl_{12}O_{19}:Ce_x{^{3+}}$,$Eu_{0.01}{^{2+}}$ phosphors were synthesized through a combustion process and their optical properties were investigated using time-resolved photoluminescence. A PL spectrum showed two dominant peaks which appeared at 300 and 410 nm. It is seen that, as the $Ce^{3+}$ concentration increases, the intensity of 300 nm decreases and the intensity of 410 nm increases. This behavior has been explained by two independent energy transfer mechanism. The first energy transfer occurs from $Ce^{3+}$ ion to $Eu^{3+}$ ion. The second energy transfer takes place from $Ce^{3+}$ ion to $Ce^{3+}-O_{ME}$ complex created in the magnetoplumbite structural host materials. The blue emitting 410 nm peak has been explained by both energy transfer mechanisms.

Theoretical Studies on the Cationic Polymerization Mechanism of Oxetanes(II) ($BF_3$촉매하의 옥세탄 공중합에 관한 분자 궤도론적 연구)

  • Park, Jeong Hwan;Cho, Sung Dong;Park, Seong Kyu;Cheun, Young Gu
    • Journal of the Korean Chemical Society
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    • v.40 no.1
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    • pp.11-19
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    • 1996
  • The cationic polymerization of energetic substituted oxetanes which have pendant energetic group such as azido and nitrato are investigated theoretically, using semiempirical HF/3-21G, MINDO/3, MNDO and AM1 method. The stereo- and electronic structure of binary molecular complex composed of energetic substituted oxetane and boron trifluoride can be explain by molecular orbital theory. The reactivity of propagation in the copolymerization of oxetanes can be presented by the positive charge on carbon(C2) atom of oxetane and energy level of the lowest unoccupied molecular orbital(LUMO) of propagating species of oxetanes. The reactivity ratios for copolymerization of oxetanes are a random copolymer-zation which is agree with MO calculated and experimental results. The relative equlibrium concentration of cyclic oxonium and open carbenium ions is found to be a major determinant of mechanism, owing to the rapid equilibrium of these cation forms and the expectation based on calculation that in the prepolymer propagation step, SN1 mechanism will be at least as fast as that for SN2 mechanism.

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HgCdTe Junction Characteristics after the Junction Annealing Process (열처리 조건에 따른 HgCdTe의 접합 특성)

  • Jeong, Hi-Chan;Kim, Kwan;Lee, Hee-Chul;Kim, Hong-Kook;Kim, Jae-Mook
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.32A no.2
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    • pp.89-95
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    • 1995
  • The structure of boron ion-implanted pn junctio in the vacancy-doped p-type HgCdTe was investigated with the differential Hall measurement. The as-implanted junction showed the electron concentration as high as 1${\times}10^{18}/cm^{3}$ and the junction depth of 0.6.mu.m. When the HgCdTe junction was heated in oven, the electron concentration near the junction decreased and the junction depth increased as the annealing temperature and time increased. The junction structure after the thermal annealing was n$^{+}$/n$^{-}$/p. For the 200.deg. C 20min annealed sample, the electron mobility was 10$^{4}cm^{2}/V{\cdot}$s near the surface(n$^{+}$), and was larger thatn 10$^{5}cm^{2}/V{\cdot}$s near the junction(n$^{+}$). The junction formation mechanism is conjectured as follows. When HgCdTe is ion-implanted, the ion energy generates crystal defecis and displaced Hg atoms HgCdTe is ion-implanted, the ion energy generates crystal defecis and displaced Hg atoms near the surface. The displaced Hg vacancies diffuse in easily by the thernal treatment and a fill the Hg vacancies in the p-HgCdTe substrate. With the Hg vacancies filled completely, the GfCdTe substrate becomes n-type because of the residual n-type impurity which was added during the wafer growing. Therefore, the n$^{+}$/n$^{-}$/p regions are formed by crystal defects, residual impurities, and Hg vacancies, respectively.

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