• 한국전자통신학회논문지
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• 제17권1호
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• pp.1-12
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• 2022

내부자의 정보 노출 사고가 지속해서 발생하면서, 조직 내부의 정보보안 강화에 대한 요구가 높아지고 있다. 그러나 엄격한 정보보안 정책 및 규칙이 조직원에게 적용될 때 정보보안 스트레스와 저항 행동으로 나타날 수 있다. 본 연구는 내부자의 정보보안 정책의 부정적 행동 원인과 완화 요인을 제시하는 것을 목적으로 한다. 특히, 개인(심리적 권한) 및 조직(공정성 분위기) 요인이 어떻게 상호 영향을 주어 부정적 행동을 완화하는지를 확인하고자 하였다. 연구는 정보보안 정책을 내부자에게 반영하는 조직의 근로자에게 설문하여 표본을 확보했으며, 구조방정식모델링으로 가설검증을 하였다. 분석 결과, 정보보안 관련 심리적 권한이 정책 저항에 미치는 영향을 업무 스트레스가 부분 매개 효과를 가졌으며, 공정성 분위기가 심리적 권한의 영향을 강화하였다. 연구 결과는 내부자의 정보보안 정책 저항 감소를 위한 방향성을 제시하였으므로, 조직 내부의 보안 목표 달성을 위한 전략 수립에 도움을 준다.

• The Plant Pathology Journal
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• 제29권2호
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• pp.201-208
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• 2013

Drought stress is one of the major yield affecting factor for pepper plant. The effects of PGPRs were analyzed in relation with drought resistance. The PGPRs inoculated pepper plants tolerate the drought stress and survived as compared to non-inoculated pepper plants that died after 15 days of drought stress. Variations in protein and RNA accumulation patterns of inoculated and non-inoculated pepper plants subjected to drought conditions for 10 days were confirmed by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and differential display PCR (DD-PCR), respectively. A total of six differentially expressed stress proteins were identified in the treated pepper plants by 2D-PAGE. Among the stress proteins, specific genes of Cadhn, VA, sHSP and CaPR-10 showed more than a 1.5-fold expressed in amount in B. licheniformis K11-treated drought pepper compared to untreated drought pepper. The changes in proteins and gene expression patterns were attributed to the B. licheniformis K11. Accordingly, auxin and ACC deaminase producing PGPR B. licheniformis K11 could reduce drought stress in drought affected regions without the need for overusing agrochemicals and chemical fertilizer. These results will contribute to the development of a microbial agent for organic farming by PGPR.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.101.2-102
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• 2003

The ability of P. chlororaphis O6 to induce resistance to Erwinia carotovora subsp. carotovara SCCI and to promote growth in tobacco was demonstrated in microtiter assays on plants pre-inoculated at the root level with the bacteria before challenge with the leaf pathogen. To identify th bacterial determinants involved in induced systemic resistance and plant growth promotion, cell culture of O6 grown in King's medium B was fractionated with organic solvents and purified using various columns. in vivo and in vitro assays with samples from successive fractionation steps of the O6 supernatant led to the conclusion that antibacterial compounds were observed in aqueous layer, and to the isolation of fractions containing metabolites that retained most of the resistance-inducing activity (70：30, methanol：water) and the plant growth promotion (80：20 and 90：10, methanol：water) after ODS column chromatography. Although these molecules remain to be purified further and structurally characterized, its isolation is an addition to the range of determinants from plant growth-promoting rhizobacteria known to stimulate plant defence.

• 한국축산식품학회지
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• 제34권1호
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• pp.20-25
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• 2014

This study evaluated the effects of frankfurter fat content on Listeria monocytogenes resistance to heat stress and gastric fluid, and the Caco-2 cell invasion efficiency of the pathogen. A 10-strain mixture of L. monocytogenes was inoculated on frankfurters formulated with 10%, 20%, and 30% fat content (10%: F10, 20%: F20, 30%: F30) and stored at $10^{\circ}C$ for 30 d. The samples were analyzed for L. monocytogenes resistance to heat stress and a simulated gastric fluid challenge. The total bacteria and L. monocytogenes survival rates were measured on tryptic soy agar plus 0.6% yeast extract and Palcam agar, respectively. L. monocytogenes colonies inoculated on F10, F20, and F30 samples were used for a Caco-2 cell invasion assay. In general, no obvious differences were observed between the survival rates of total bacteria and L. monocytogenes grown on different fat contents under heat stress and gastric fluid challenge. However, L. monocytogenes obtained from the F30 samples had a significantly higher Caco-2 cell invasion efficiency than those in the F10 and F20 samples (p<0.05). These results indicate that although high fat content in food may not be related to L. monocytogenes resistance to heat stress and gastric fluid, it may increase the Caco-2 cell invasion efficiency of the pathogen.

• Journal of Microbiology and Biotechnology
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• 제17권4호
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• pp.586-593
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• 2007

Seed coating by a phenazine-producing bacterium, Pseudomonas chlororaphis O6, induced dose-dependent inhibition of germination in wheat and barley seeds, but did not inhibit germination of rice or cucumber seeds. In wheat seedlings grown from inoculated seeds, phenazine production levels near the seed were higher than in the roots. Deletion of the gacS gene reduced transcription from the genes required for phenazine synthesis, the regulatory phzI gene and the biosynthetic phzA gene. The inhibition of seed germination and the induction of systemic disease resistance against a bacterial soft-rot pathogen, Erwinia carotovora subsp. carotovora, were impaired in the gacS and phzA mutants of P chlororaphis O6. Culture filtrates of the gacS and phzA mutants of P. chlororaphis O6 did not inhibit seed germination of wheat, whereas that of the wild-type was inhibitory. Our results showed that the production of phenazines by P. chlororaphis O6 was correlated with reduced germination of barley and wheat seeds, and the level of systemic resistance in tobacco against E. carotovora.

• Journal of Korean Biological Nursing Science
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• 제6권2호
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• pp.5-17
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• 2004

Purpose: The purpose of this study is to determine effects of aromatherapy on the activity and balance of autonomic nervous system and on physical resistance to stress. Methods: This research is a primitive experimental design which attempts to analyze aromatherapy EKG monitoring on real-time basis. Lavender & Chamomile, each 30 drops, were blended with 100ml Sweet Almond oil. Subjects was laid relaxed, and had insides of his wrists and ankles attached with electrodes for EKG. Right after applied with essential oil onto his philtrum and parotid, started on EKG monitoring. Results: The activities of parasympathetic and sympathetic nerve were changed as time elapsed, with significant differences(p=.000). In multiple comparison, the value was significantly different(p<.05).The balance of autonomic nerve was changed, becoming close to the normal level in accord with applicable international standards(1.5)(p=.011). In multiple comparison, the value showed a significant difference(p<.05). Physical resistance to stress increased with the passage of time, but not statistically significant. Conclusions: This suggests that aromatherapy can be used as a nursing intervention which aims at alleviating symptoms related to the imbalance of autonomic nerve system such as headache, hot flashes, irregular heartbeat, nervousness, depression and anxiety.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.331-340
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• 2009

This study evaluates the relationship between cone tip resistance ($q_c$) and small-strain shear modulus ($G_{max}$) of cemented sand. For this purpose, a series of miniature cone penetration and bender element tests are performed in calibration chamber specimens with various gypsum contents. Experimental results show that both $q_c$ and $G_{max}$ of sand increase with increasing cementation level as well as relative density and vertical confining stress. However, the relative density and vertical confining stress has more significant influence on $G_{max}$ and $q_c$ of uncemented sand than those of cemented sand. It is observed that the $G_{max}/q_c$ ratio of cemented sand decreases with increasing relative density. This result means that state variables have more affect on $q_c$ than $G_{max}$ of cemented sand. Test results also show that the effect of vertical stress on $G_{max}-q_c$ relation is reduced by cementation effect.

• Physical Therapy Rehabilitation Science
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• 제10권2호
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• pp.134-140
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• 2021

Objective: The purpose of this study was to investigate the alteration of upper cervical manipulation to autonomic nervous system (ANS) through the heart rate variability(HRV) analysis in young healthy individuals. Design: Two-group pretest-posttest design. Methods: Thirty four young healthy participants (17 males and 17 females) were randomized into the 2 groups, such as the upper cervical manipulation group (UCM group, n=17), neck stretching group (NS group, n=17). UCM group received a upper cervical manipulation, especially on the atlas, and NS group did stretch for both side of upper trapezius and levator scapular. For the UCM, Atlas mobility was checked by therapist and thrust was given once at the posterior arch of Atlas. HRV was measured before and after intervention to investigate ANS alteration. After the intervention, both groups were given 3 minutes break-time before measuring HRV. Results: The UCM group showed significant differences in ANS Activity, Stress Resistance, Stress index and Fatigue Index (p<0.05) while no differences in NS group with before and after intervention. There were significant differences in ANS Activity, Stress Resistance, and Fatigue Index between groups (p<0.05). Conclusions: This study suggected that upper cervical manipulationhas positive effects on the ANS activity, stress resistance, and fatigue index.

• 대한치과기공학회지
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• 제45권3호
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• pp.61-66
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• 2023

Purpose: The current study examined the retention and wear resistance of stud-type attachments made of high-performance polyetheretherketone (PEEK) or polyetherketoneketone (PEKK) from the polyaryletherketones (PAEKs) family. Methods: The study sample included 10 PEEK or PEKK attachments that were mounted onto their male parts, designed on the upper aspect of the attachment, with a load of 30 N. Tensile stress was applied using an Instron machine to separate the male and female parts, and the maximum tensile stress to be applied was determined based on the retention force observed. The wear resistances of PEEK and PEKK were evaluated by measuring the inner diameter of the inserted female part 10 times. Results: The maximum tensile stresses of PEEK and PEKK were 56.26±0.58 and 69.12±0.92 N, respectively, with the maximum stress required to remove the PEKK specimens from the abutment being 12.86 N higher than that required to remove the PEEK specimens. Furthermore, PEKK exhibited higher wear resistance than PEEK. Conclusion: This study evaluated custom-made removable implant-retained attachment components for overdentures, wherein the female parts were made of PEEK or PEKK. The retention stress and wear resistance were evaluated based on the type of attachment material, and the results showed that both types of attachment inserts demonstrated clinically acceptable results in terms of retention.

• Journal of Welding and Joining
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• 제16권1호
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• pp.114-124
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• 1998

The effect of matrix phase (austenite, pearlite, martensite) on the low stress abrasion resistance in the chromium-carbide-type high Cr white iorn hardfacing weld deposites has been investigated. In order to examine matrix phase, a series of alloys with different matrix phase by changing the ratio of Cr/C system by heat treatment were employed. The alloys were deposited twice on a mild steel plate using self-shielding flux cored arc welding process. The low stress abrasion resistance of the alloys against sands was measured by the Dry Sand/Rubber Wheel Abrasion Test(RWAT). Even though formation of pearlite phase in the matrix showed higher hardness than that of austenite, there was no observable difference in wear resistance between the pearlite and austenite phase for the same amount of chromium-carbide in the matrix. On the other hand, the formation of martensitic phase,, from heat treated austenitic alloys (high content of Cr), enhanced wear resistance due to its fine secondary precipitates.