• Title/Summary/Keyword: Passive behavior

Search Result 590, Processing Time 0.03 seconds

Electrochemical Analysis on Flow-Accelerated Corrosion Behavior of SA106 Gr.C Steel in Alkaline Solution

  • Kim, Jun Hwan;Kim, In Sup;Chung, Han Sub
    • Corrosion Science and Technology
    • /
    • v.2 no.1
    • /
    • pp.41-46
    • /
    • 2003
  • Flow-Accelerated Corrosion behavior concerning both activation and mass transfer process of SA106 Gr.C steel was studied using rotating cylinder electrode in room temperature alkaline solution by DC and AC electrochemical techniques. Passive film was tanned from pH 9.8 by step oxidation of ferrous product into hydroxyl compound. Corrosion potential shifted slightly upward with rotating velocity through the diffusion of cathodic species. Corrosion current density increased with rotating velocity in pH 6.98, while it soon saturated from 1000 rpm at above pH 9.8. On the other hand the limiting current increased with rotating speed regardless of pH values. It seems that activation process, which represents formation of passive film on the bare metal surface, controls the entire corrosion kinetics

A Study on Thermal Environment and Residents' Usage Behaviors of Cooling Devices in Apartments' Living Rooms (여름철 집합주택의 거실 온열 환경의 측정 및 거주자의 냉방기 사용행위에 관한 연구)

  • Bae, Nu-Ri;Chun, Chung-Yoon
    • Proceeding of Spring/Autumn Annual Conference of KHA
    • /
    • 2004.11a
    • /
    • pp.323-328
    • /
    • 2004
  • This study measured the thermal environment and residents' cooling behavior of the apartments' living rooms in summer in Seoul. The purpose of this study is to find out the present thermal environment of the living rooms and to find out the target figure of passive cooling system. The surveys and measurements took place in six apartments of Seoul for 60days(2004. 7. 3${\sim}$2004. 8. 31). The result were summarized as follows; The thermal environment of apartments' living rooms were almost neutral, and residents felt a little uncomfortable. Residents turned on the air conditioner at $27.31^{\circ}C$ of indoor temperature, and $28.89^{\circ}C$ of SET*. Therefore, cooling critical temperature of the passive cooling system can be figured out from this result.

  • PDF

The effects of consumers' perceptions and expectations for refund on the result of refund request (소비자의 환불필요성 인식 및 환불성공 기대가 환불요구결과에 미치는 영향)

  • Huh Kyungok
    • Journal of Family Resource Management and Policy Review
    • /
    • v.8 no.3
    • /
    • pp.33-46
    • /
    • 2004
  • This study examined the effects of consumers' perceptions and expectations about refund on consumers' behavior to refund and its outcome. Major results of this study could be summarized as follows. First, consumers' perceptions and expectations about refund were higher in the case of defective products. However, consumers' behavior to refund were generally passive resulting in the low chance of refund. When there was no defects in product, consumers perceptions and expectations for refund were generally lower resulting in passive and the low chance of refund. Second, when there was defects in product, both consumers' perceptions and expectation tot refund influenced their active behaviors for refund, but not in the successful outcome. In contrast, when there was no defect, those two variables impacted on the behaviors for refund positively In addition, the more active those behaviors requesting for refunds were, the more successful outcome in refund request.

  • PDF

Experimental Behavior Analysis of Double Isolated Anti-Vibration System (2중방진 시스템의 실험적 거동해석)

  • 이홍기;이신언
    • Journal of KSNVE
    • /
    • v.2 no.4
    • /
    • pp.281-292
    • /
    • 1992
  • Two types of vibration problems are encountered in industrial field: active isolation and passive isolation. In a passive type of vibration isolation, a foundation of a delicated machinery such as TEM, SEM, inspection- probe test, photolithograph, etc. is designed to have a vibration amplitude lower than an acceptable limit. In an active type, the isolation is focused on the vibration reduction caused by the machine itself(pump, motor, press, compressor, etc.). The foundation for such a machine should be so designed as to reduce the transmitted vibration below the permissible level prescribed. At any case, a transmissibility and stability must to be considered. Since an active isolation type is aimed for a vibration source, it is useful to isolate the transmitted vibrations energy from a major vibration source at the specific location. In this paper, a designed methodology of double anti-vibration system has been examined in order to have low transmissibility and reliable stability. Also experiment of scale model behavior has been conducted. Finally, the experiment output of the transfer function is compared to the analytical data.

  • PDF

Effects of Alloying Elements on the Pitting Behavior of Ti-Al Intermetallic Compounds (TiAl 금속간화헙물의 공식거동에 미치는 합금원소의 영향)

  • 이호종;최한철
    • Journal of Surface Science and Engineering
    • /
    • v.31 no.3
    • /
    • pp.157-164
    • /
    • 1998
  • Effects of alloying elements on the pitting behavior of Ti-Al intermetalic compounds in the electrolytic soution containing Cl- were investigated through electrochemical tets and corrosion morphologies. Corrosion potential increased in the case of Cr addition to Ti-48%Al, whereas it decreased in the case of Si and B addition. The simultaneous addition of Cr and Si increased passive current density and decrosion corrosion potential. The passive current density of N addtion was higher than that of B addition in H2SO4 solution. With the addition of alloying elements, The pitting resistance decreased in order of TiAl>TiAlSi>TiAlN>TiAlB>TiAlCr and whin siumultaneous addition, it decreased in order of TiAlCrSi>TiAlCrBN>TiAlCrrN. The surface merohology after pitting test showed that the TiAl coataining Si had for fewer pits than that containing Cr and N simultaneously.

  • PDF

Effects of Alloyed Carbon on the General Corrosion and the Pitting Corrosion Behavior of FeCrMnN Stainless Steels (FeCrMnN 계 스테인리스강의 일반부식 및 공식부식 거동에 미치는 고용 탄소의 영향)

  • Ha, Heon-Young;Lee, Tae-Ho;Kim, Sung-Joon
    • Korean Journal of Metals and Materials
    • /
    • v.49 no.10
    • /
    • pp.780-789
    • /
    • 2011
  • The effects of alloyed carbon on the pitting corrosion, the general corrosion, and the passivity behavior of Fe18Cr10Mn0.4NxC (x=0~0.38 wt%) alloys were investigated by various electrochemical methods and XPS analysis. The alloyed carbon increased the general corrosion resistance of the FeCrMnN matrix. Carbon enhanced the corrosion potential, reduced the metal dissolution rate, and accelerated the hydrogen evolution reaction rate in various acidic solutions. In addition, carbon promoted the pitting corrosion resistance of the matrix in a chloride solution. The alloyed carbon in the matrix increased the chromium content in the passive film, and thus the passive film became more protective.

A study on online WOM search behavior based on shopping orientation (의복쇼핑성향에 따른 온라인 구전 정보탐색행동에 관한 연구)

  • Lee, Angie;Rhee, YoungJu
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.20 no.4
    • /
    • pp.57-71
    • /
    • 2018
  • Since consumers have become more comfortable with providing and receiving information online, 'online word of mouth' has been gaining consideration as one of the major information sources. Also, the shopping orientation of consumers has been proven to be an important determinant of consumer behavior. Therefore, the study investigated the differences in online WOM behavior based on shopping orientation. Hedonic, loyal, and syntonic styles were the types of shopping orientation considered, and the study focused on information retrieval tendencies, the motivation of online WOM search, searching online WOM sources, and the contents for the online WOM behavior. The research conducted an off-line survey targeting females in their twenties. The total number of data sets used in the empirical study was 125, and these were analyzed by SPSS 20.0: factors analysis, Cronbach's ${\alpha}$, k-means cluster, ANOVA, Duncan's multiple range test, Kruskal-Wallis, Mann-Whitney, and Bonferroni correction. The participants were divided into 3 kinds of shopping orientation groups named 'trend-pursuit', 'passive', and 'loyal'. As a result, there were significant differences in online WOM behavior discovered between the groups. Firstly, the 'trend-pursuit' group had the highest number of ongoing searches while the 'loyal' group had the highest number of pre-purchase search. Secondly, the 'trend-pursuit' and 'loyal' groups both had the motivations of online WOM search, hedonic and utility, whereas the 'passive' group had the lowest motivations for both motivations. Thirdly, the 'loyal' group frequently referred to reviews on shopping malls as online WOM sources. The research provided a better understanding of the online WOM behavior of present consumers and suggests that fashion related corporations map out marketing strategies with the understanding of these behaviors.

Effects of Ethanol Extract from Magnolia Officinalis on Anxiety and Cognitive Function (후박 에탄올 추출물의 불안 및 인지기능에 대한 효과)

  • Lee, Hyun-ki;Lee, Un-jung
    • The Journal of Internal Korean Medicine
    • /
    • v.36 no.4
    • /
    • pp.507-517
    • /
    • 2015
  • The bark of Magnolia officinalis has been used in traditional oriental medicine to treat a variety of mental disorders including anxiety and depression. The purpose of this study was to examine the effect of M. officinalis ethanol extract on stress-induced alterations in learning and cognitive function using a passive avoidance test (PAT) and also on anxiety-related behavior using the elevated plus-maze test (EPM) in female rats . The degree of Tyrosine hydroxylase (TH) in the region of the ventral tegmental area (VTA) and the locus coeruleus (LC) was measured using an immunohistochemical method. Corticosterone concentrations in serum were also measured. The ethanol extract from Magnolia officinalis was orally administered to female rats 30 minutes before evaluating their immobilization stress and anxiety-related behavior using an elevated plus-maze test and a passive avoidance test. Time spent in the open arms of the EPM increased in the M. officinalis-treated group compared with that of the saline-treated control group. In the passive avoidance test, the memory and cognitive function improved in the M. officinalis extract-treated group. M. officinalis extracts reduced elevated corticosterone concentrations in serum. Also, stress-induced TH increases were suppressed in the M. officinalis extract-treated group in the LC and the VTA region. These results suggest that M. officinalis might prove to be an effective anxiolytic anti-stress agent.

A Study on the Determining Factors of Work Stress Coping Strategies of Dental Hygienists (치위생사의 직무스트레스 대처전략 결정요인에 관한 연구)

  • Yoon, Young Suk
    • Journal of dental hygiene science
    • /
    • v.2 no.2
    • /
    • pp.75-83
    • /
    • 2002
  • By extracting the variables related to the work stress generated from dental hygiene, identifying their relationships, this study aims to contribute to academic progress on work stress. The test results of this study are as follows for each hypothesis: 1. Among the work stress sensing factors, role ambiguity showed correlation to the active coping strategy and the passive coping strategy, whereas it did not have any correlation to the evasive reation. However, the physical resource environmental factor showed correlation to the active coping strategy, whereas it did not have any correlation to the other reation. 2. The passive coping strategy, among the work stress coping strategies, influences the role ambiguity, B type, work ambiguity, physical resource environmental factor by about 18.7%. 3. The active coping strategy, among the work stress coping strategies, influences the social support, role ambiguity, work place of health center factor by about 18.9%. 4. The evasive reaction, among the work stress coping strategies, was influenced by only the 36 years old over factor by approximately 4.2%. 5. It was found in all work stress sensing factors that the group with lower social support had a more degree of experiencing stress than the group with higher social support. In case of the behavior pattern, the type A experienced more stress than the type B only in role ambiguity. 6. It was found that the group with the higher social support tended to choose more active coping strategy than the lower social support. In case of behavior pattern, the type B coped more actively than type A in the passive coping strategy.

  • PDF

Effect of stack configuration on the performance of 10W PEMFC stack (10W급 고분자 전해질 연료전지 스택의 구조적 차이에 다른 운전 특성 비교)

  • Yim, Sung-Dae;Kim, Byung-Ju;Sohn, Young-Jun;Yoon, Young-Gi;Yang, Tae-Hyun;Kim, Chang-Soo;Kim, Young-Chai
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2009.06a
    • /
    • pp.286-286
    • /
    • 2009
  • A small PEM fuel cell has two different stack configurations such as active and passive stacks. The active stack has a distintion of high power density although it makes system complex by using alr blower and related BOPs resulting in large system volume. On the contrary, passive stack has an advantage of compact system because it doesn't need air supplying devices although it reveals relatively low stack power density. In this study we fabricated two 10W PEMFC stacks with different stack configurations, active and passive stacks, and tested their performance and stability. The active stack consists of 13cells with an active area of $5cm^2$. The passive stack has 12cells with an active area of $16cm^2$. When we compared the stack performance of those stacks, the active stack showed higher power density compared to the passive stack, particularly at high voltage regions. However, at low voltage and high current regions, the passive stack performance was comparable to the active stack. The stack stability was largely dependent on the fuel humidity, particularly for active stack. At low humidity conditions, the active stack performance was decreased continuously and the cell voltage distribution was not uniform showing seriously low cell voltage at center cells mainly due to the cell drying. The passive stack showed relatively stable behavior at low humidity and the stack performance was largely dependent on the atmospheric conditions.

  • PDF