• 제목/요약/키워드: limitation

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The Effect of the Fill Charge Ratio on the Heat Transfer Characteristics of a Two-Phase Closed Thermosyphon (충전율의 변화가 밀폐형 2-상 열사이폰의 열전달 특성에 미치는 영향에 관한 연구)

  • Park, Yong-Joo;Hong, Sung-Eun;Kim, Chul-Ju
    • Transactions of the Korean Society of Mechanical Engineers B
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    • 제26권12호
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    • pp.1646-1654
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    • 2002
  • A two-phase closed thermosyphon was one of the most effective devices in the removing heat because of its simple structure, thermal diode characteristics, wide operating temperature range and so on. In this study, a two-phase closed thermosyphon(working fluid PFC(C6F14), container copper(inner grooved surface)) was fabricated with a reservoir which can change the fill charge ratio. The experiments were performed in the range of 50~600W heat flow rate and 10~70% fill charge ratio. The results were compared with some correlations that were presented by Rohsenow and Immura et al. in the evaporator, by Nusselt, Gross and Uehara et al. in the condenser and by Cohen and Bayley, Wallis, Kutateladze and Faghri et al. in heat transfer limitation etc.. The heat transfer coefficient at the evaporator increased with the input power. However the effect of the fill charge ratio was nearly negligible. At the condenser, it showed an opposite trend to the evaporator and with increase of the fill charge ratio, showed some enhancement of heat transfer. The heat transport limitation was occurred by the dry-out limitation for small fill charge ratio(10%) and presented about 100W. For the case of large fill charge ratio(Ψ$\geq$40%), it was occurred by the flooding limitation at about 500W.

Construction of the Phosphate-Limitation Inducible Expression Vector Containing the phoA Promoter of Enterobacter aerogenes (Enterobacter aerogenes 의 phoA 유전자 Promoter를 이용한 인 제한환경에서 발현하는 벡터 구축)

  • 장화형;고병훈;박신영;이성호;김성진;임유정;한갑진;김영호;이영근
    • Korean Journal of Microbiology
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    • 제38권4호
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    • pp.318-321
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    • 2002
  • To induce recombinant protein under phosphate restricted conditions such as soil, we have constructed the expression vector (pEAAP) with phoA gene promoter of Enterobacter aerogenes. To construct the pEAAP, deletion of the T7 promoter and lac operator from pET-22b(+) by BglII-XhoI digestion and addition of the phoA gene promoter (containing the pho box) were performed. To test pEAAP as an expression vector controled by phosphate limitation, pEAPHY1 was constructed with the phytate gene (Bsa-phy1) of Bacillus subtillis var. amyloliquefaciens (KCTC 8913P). Under the phosphate-limitation condition, CK-PHY1 ( Escherichia coli JM109 was transformed with pEAPHY1) expressed the 41 kD Bsa-Phy1 . Also CK-PHY1 formed the clear zone in solid medium containing phytate as a sole phosphate source.

Fault current limitation characteristics of the Bi-2212 bulk coil for distribution-class superconducting fault current limiters (배전급 초전도 한류기 개발을 위한 Bi-2212 초전도 한류소자의 사고전류 제한 특성)

  • Sim, Jung-Wook;Kim, Hye-Rim;Yim, Seong-Woo;Hyun, Ok-Bae;Lee, Hai-Gun;Park, Kwon-Bae;Kim, Ho-Min;Lee, Bang-Wook;Oh, Il-Sung;Breuer, Frank;Bock, Joachim
    • Proceedings of the KIEE Conference
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.639-640
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    • 2006
  • We investigated fault current limitation characteristics of the resistive superconducting fault current limiter(SFCL) which consisted of a Bi-2212 bulk coil and a shunt coil. The Bi-2212 bulk coil and the shunt coil were connected in parallel. The Bi-2212 bulk coil was placed inside the shunt coil to induce field-assisted quench. The fault test was conducted at an input voltage of 200 $V_{rms}$ and fault current of 12 $kA_{rms}$ and 25 $kA_{rms}$. The fault conditions were asymmetric and symmetric, and the fault period was 5 cycles. The test results show that the SFCL successfully limited the fault current of 12 $kA_{rms}$ and 25 $kA_{rms}$ to below $5.5{\sim}6.9kA_{peak}$ within $0.64{\sim}2.17$ msec after the fault occurred. Limitation was faster under symmetric fault test condition due to the larger change rate of current. We concluded that the speed of fault current limitation was determined by the speed of current rise rather than the amplitude of a short circuit current. These results show that the Bi-2212 bulk coil is suitable for distribution-class SFCLs.

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Effects of p variation and phosphate limitation on the continuous fermentation of Clostridium acetobutylicum (pH 변화와 인산 제한이 Closoidium acetobutylicum의 연속발효에 미치는 영향)

  • 신순영;김병흥
    • KSBB Journal
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    • 제5권1호
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    • pp.9-17
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    • 1990
  • The growth and fermentation profiles of Clostridium acetobutylicum KCTC 1037 were examined in batch and continuous modes with pH variation and phosphate limitation. Clostridium acetobutylicum KCTC 10 37 grew better at pH 4.5 than at pH 5.5 or 6.5. Acetate and butyrate were produced at pH 5.5, whereas culture at pH 4.5 produced acetone and butanol. Solvent production was increased by the phosphate limitation in a batch culture, but in a phosphate-limited continuous culture for 400 hours steady-state solventogenesis was not observed. The induction and maintenance of solventogenesis presumably require not only acidic condition or phosphate limitation but also favourable bioenergetic condition.

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Factors Associated with Indacaterol Response in Tuberculosis-Destroyed Lung with Airflow Limitation

  • Kim, Tae Hoon;Rhee, Chin Kook;Oh, Yeon-Mok
    • Tuberculosis and Respiratory Diseases
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    • 제82권1호
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    • pp.35-41
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    • 2019
  • Background: Pulmonary tuberculosis can result in anatomical sequelae, and cause airflow limitation. However, there are no treatment guidelines for patients with a tuberculosis-destroyed lung. Recently, indacaterol effectiveness in chronic obstructive pulmonary disease (COPD) patients with Tuberculosis history (INFINITY) study revealed indacaterol provided bronchodilation and symptom improvement in COPD patients with a tuberculosis-destroyed lung. Methods: We conducted a post-hoc subgroup analysis of the randomized controlled trial, the INFINITY study, to determine factors associated with indacaterol response in a tuberculosis-destroyed lung with airflow limitation. Data from 68 patients treated with inhaled indacaterol, were extracted and analyzed. Factors associated with the response of forced expiratory volume in one second ($FEV_1$) to indacaterol treatment, were determined using linear regression analysis. Results: Of 62 patients included, 68% were male, and 52% had history of cigarette smoking. Patients revealed mean $FEV_1$ of 50.5% of predicted value with mean improvement of 81.3 mL in $FEV_1$ after indacaterol treatment for 8 weeks. Linear regression analysis revealed factors associated with response of $FEV_1$ to indacaterol included a short duration of smoking history, and high short-acting bronchodilator response. When patients with history of smoking were excluded, factors associated with response of $FEV_1$ to indacaterol included high short-acting bronchodilator response, and poor health-related quality of life score as measured by St. George's Respiratory Questionnaire for COPD. Conclusion: In a tuberculosis-destroyed lung with airflow limitation, short-acting bronchodilator response and smoking history can play a critical role in predicting outcomes of indacaterol treatment.

The Problem of Self-Limitation in Therapeutic Culture: Focusing on Misery Memoirs (치유문화에서 나타나는 자아 제한성의 문제: 고통수기들을 중심으로)

  • Seoh, Gilwan
    • English & American cultural studies
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    • 제14권1호
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    • pp.73-94
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    • 2014
  • Accounts from therapeutic culture seem often to associate the selfish, or at least self-centered quest for self-fulfillment with individual choice or satisfaction, self-expression, expressive individualism, and emotionalism. These associations point to the downside of therapy as they present it as constituting a culture of narcissism, selfishness, or irresponsibility. While some of these characterizations contain useful insights, they overlook what are maybe some of the most important features of a therapeutic outlook. This paper aims to reveal that the therapeutic imperative is not so much geared towards the realization of self-fulfillment, as it is the promotion of self-limitation. Therapeutic culture tends to posit the self in a fragile and feeble form and insist that the management of life requires the continuous intervention of therapeutic expertise. Because of this, the elevated concern with the self is underpinned by anxiety, pain, suffering, and survival, rather than seen as a positive vision of realizing the human potential. Therapeutic culture has in this way helped to construct a diminished sense of self by which one is seen as suffering from an emotional deficit and vulnerability. This paper demonstrates this downside of therapeutic culture concerning self-limitation and the sense of a diminished self by examining popular "misery memoirs." Misery memoirs are widely consumed by the general public, therefore tend to be treated by contemporary therapeutic culture as a gospel on the therapeutic ideal for self-fulfillment and self-discovery. This is, despite the existence of hidden evidence to the contrary, because of their redemptive, happy endings that show individuals overcoming difficult trials such as child abuse, incestuous rape, and domestic violence. Individual self-fulfillment and self-discovery in such stories are not achieved through the active agency of the subject but through the passive endurance of pathological symptoms and with the aid of expertise and outside support. Therefore, such stories put victims in the limited position.

The Development of a One-time Password Mechanism Improving on S/KEY (S/KEY를 개선한 일회용 패스워드 메커니즘 개발)

  • 박중길
    • Journal of the Korea Institute of Information Security & Cryptology
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    • 제9권2호
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    • pp.25-36
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    • 1999
  • In this paper we propose a one-time password mechanism that solves the problems of the S/KEY: the limitation of a usage and the need of storage for keys. because of using a cryptographic algorithm the proposed mechanism has no the limitation of a usage. Also because of producing the key for an authentication from a user's password it is easy to manage the authentication key and is possible to share the session key between a client and a server after the authentication process. In addition the proposed mechanism is easy to protect and manage the authentication information because of using a smart card and is adopted by the system that needs a noe-way authentication from a client to a server without the challenge of a server.

Factors associated with levels of health-related quality of life in elderly women: secondary data analysis of the Korea National Health and Nutrition Examination Survey 2019 (여성노인의 건강관련 삶의 질 수준별 관련요인: 국민건강영양조사(2019년) 자료를 이용한 이차자료분석)

  • Son, Miseon
    • Women's Health Nursing
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    • 제28권3호
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    • pp.187-196
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    • 2022
  • Purpose: The purpose of this study was to investigate factors related to the levels of health-related quality of life (HRQoL) in elderly women based on Wilson and Cleary's HRQoL model. Methods: This study analyzed data from the eighth Korea National Health and Nutrition Examination Survey 2019 on 868 women over the age of 65 years. Based on the HRQoL model, parameters were categorized as personal, environmental, and physiological characteristics; symptom status; functional status; and perception of health status. The data were analyzed by quantile regression. Results: The overall level of HRQoL was 0.87. Factors related to HRQoL in the 10% quantile were higher education level, higher economic status, economic activity, more walking days, fewer diseases, lower stress, less activity limitation, and higher perceived health status. Factors related to the 25% quantile of HRQoL were more walking days, fewer diseases, less activity limitation, and higher perceived health status. Factors related to the 50% quantile were age, economic activity, more walking days, fewer disease, lower stress, less activity limitation, and higher perceived health status. Factors related to the 75% quantile of HRQoL were smoking, more walking days, fewer diseases, lower stress, less activity limitation, and higher perceived health status. Conclusion: While differing parameters were identified according to the level of HRQoL of elderly women in Korea, there were five common factors. Interventions that focus on increasing walking, mitigating diseases, stress, and activity limitations, and improving perceived health status can improve HRQoL.

Luxurious Phosphorus and Phosphorus Limitation for Epiphytic and Planktonic Algal Growth in Reed Zones of Lake Biwa

  • Osamu, Mitamura;Choi, Jun-Kil
    • Korean Journal of Ecology and Environment
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    • 제41권4호
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    • pp.554-562
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    • 2008
  • To evaluate the limitation for epiphytic and planktonic algal growth, acid extractable inorganic phosphorus (AP), implying the luxury uptake phosphorus, was measured in five reed zones of Lake Biwa. The AP in epiphytic substances was 0.7 to 1.4 mg P surface stem $m^{-2}$ in summer and 1.2 to 2.8 mg P $m^{-2}$ in winter. On the other hand, the amount in planktonic substances was 1.4 to 5.7 mg P m -3 and 0.8 to 5.4 mg P $m^{-3}$ in both seasons. Contribution of AP in the epiphytic and planktonic phosphorus was 23 to 31% and 8 to 27% in summer, and 17 to 22% and 9 to 17% in winter. It suggests that in summer both epiphytic and planktonic algae had been luxuriously taken up phosphate into cells. The weight ratios of C : N : P were averaged 79 : 20 : 1 for the epiphytic substances and 81 : 12 : 1 for the particulate substances. On the other hand, the ratios without the luxurious phosphorus were 93 : 24 : 1 and 103 : 15 : 1, showing much higher values than the Redfield ratio. High ratio in the epiphytic substances indicates that the phosphorus is the limiting parameter, rather than nitrogen, regulating the growth of epiphytic algal populations.

The Challenge of Arbitral Awards in Pakistan

  • Mukhtar, Sohaib;Mastoi, Shafqat Mahmood Khan
    • Journal of Arbitration Studies
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    • 제27권1호
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    • pp.37-57
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    • 2017
  • An arbitrator in Pakistan is required to file an arbitral award in a civil court of competent jurisdiction for its recognition and enforcement if an arbitral award is domestic or before the concerned High Court if the arbitral award is international. The court of law is required to issue a decree upon submitted arbitral award if an interested party do not apply for modification or remission of an arbitral award and do not challenge it for setting it aside or for revocation of its recognition and enforcement within a prescribed time limit. The challenging process of an arbitral award can be started by the aggrieved party of an arbitration agreement at the seat of arbitration or at the place where recognition and enforcement of an arbitral award is sought. The aggrieved party to an arbitration agreement is required to challenge an arbitral award within a prescribed time limit if contracting parties have not excluded the right to challenge an arbitral award. Limitation for challenging an arbitral award in Pakistan is 30 days under article 158 of the Limitation Act 1908, starting from the date of service of notice of filling of an arbitral award before the court of law. Generally, 90 days are given for an appeal against decision of the civil court of law under section 96 of the Code of Civil Procedure 1908, it is therefore highly recommended that challenging time of an arbitral award should be increased from 30 to 90 days.