• Title/Summary/Keyword: instability analysis

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Is BTC Oil Pipeline Good or Bad for Azerbaijan Economy? (BTC 파이프라인이 아제르바이잔 경제에 미치는 영향 분석)

  • Hwang, Yun Seop;Kim, Soo Eun;Choi, Young Jun
    • Environmental and Resource Economics Review
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    • v.19 no.2
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    • pp.413-440
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    • 2010
  • Since 2000, as importance of sourcing energy emphasized caused by instability of international oil price, interests toward Caspian countries as an alternative markets has increased. Especially, Azerbaijan, as middle Asian emerging exporting country, has performed drastic economic boom because of massive amount of foreign capital flowed in and construction of BTC pipeline. However, despite this economic surge, there are unbalanced economy which is merely focusing on energy industry and pressure from increase in real exchange rate and inflation. In order to analyze the sustainability of Azerbaijan economy, the total sample time period of this paper is from January 2001 to December 2007 and the term is divided into before and after BTC line construction. Vector Error-Correction Model has been applied to analysis confirming short-term and long-term effect. As a result, Azerbaijan now face the symptoms of the recession during the time period and this is due to high oil price and increase in export influenced by BTC oil pipeline resulting in decrease in real interest rate. This conclusion is to affect competitiveness of manufacturing industry, base industry for economic proliferation, in a negative way.

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Deterioration Analysis and Source Area on Rock Properties of the Seokgatap Pagoda in the Bulguksa Temple, Korea (불국사 석가탑의 풍화훼손도 분석 및 기원암의 산지추정)

  • Lee, Myeong-Seong;Lee, Chan-Hee;Suh, Man-Cheol;Choi, Seok-Won
    • 한국문화재보존과학회:학술대회논문집
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    • 2004.10a
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    • pp.15-24
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    • 2004
  • The Seokgatap pagoda composed of mainly alkali granite and other minor pink-feldspar granite, fine-grained granite, granodiorite, diorite, gabbro, and tuff. Despite the small loss and damage derived from joints, its peel-off and exfoliation are serious enough to cause the heavy deterioration on the stone surface. The chemical and petrological weathering has partly replaced the original rock-forming minerals with clay minerals and iron oxyhydroxides. Based on the petrogenesis, rock materials of the pagoda is very similar to rocks of Dabotap pagoda and the Namsan granite in the Gyeongju. The central fart of the pagoda has sunken highly, which caused all the corners to split and the structural transformation to become worse. The reverse V-shaped gaps between the materials have broken stones filled in a coarse way. The iron plates inserted between the upper flat stone laid on other stones and tile pagoda body in the north and east side has been exposed in the air and corroded, discoloring of the adjacent stones. The overall diagnosis of the Seokgatap pagoda is the deteriorated functions of the stone materials, which calls for a long-term monitoring and plans to reinforce the stone surfaces. But the main body including the pagoda roof stone needs washing on a regular basis, and the many different cracks should be fixed with glue by using the fillers or hardeners designed for stone cultural properties after removing the cement mortar. In case of the replacement of the stone materials with new stones, it's necessary to examine the pagoda for the center of gravity and support intensity of the materials. The structural stability of the pagoda can be attained by taking a reinforce measure in geotechnical engineering and making a drainage. The ground humidity, which has aggravated weathering and structural instability, should be resolved by setting up a humidity reduction facility. The contamination of lichens and bryophyte around the pagoda and on the surface is serious. Thus biochemical treatments should be given too in order to prevent further biological damages and remove the vegetation growing on the discontinuous planes.

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A Study on the Stabilization of the Papain Enzyme in the Moderately Concentrated Anionic Surfactant System (음이온 계면활성제에서 파파인 효소의 안정도에 관한 연구)

  • Kim, Ji-Yeong;Kim, Jin-Woo;Kim, Yong-Jin;Lee, Jae-Wook;Lee, Hae-Kwang;Kang, Hak-Hee
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.33 no.2
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    • pp.93-97
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    • 2007
  • Even in the moderately concentrated anionic surfactant system, some special encapsulation method can shield the papain enzyme from proteolytic attacks. The stabilization of enzyme has been a major issue for successful therapies. In this study, we first stabilized an enzyme, papain in the microcapsules by using polyols, polyethyleneglycol (PEG), poly-propyleneglycol (PPG), and PEG-PPG-PEG block copolymer. In the analysis of EDS and CLSM, it was demonstrated that polyols are effectively located in the interface of papain and polymer. Polyols located in the interface had an ability to buffer the external triggers by hydrophobic partitioning, preventing consequently the catalytic activity of papain in the micro-capsules. Second. we introduced multi-layer capsulation methods containing ion complex. Such a moderately concentrated anionic surfactant system as wash-off cleansers, surfactants and waters can cause instability of entrapped enzymes. Surfactants and water in our final products swell the surface of enzyme capsules and penetrate into the core so easily that we can not achieve the effect of enzyme, papain. In this case, the ion complex multi-layer capsule composed of sodium lauroyl sarcosinate and polyquaternium-6 could effectively prevent water from penetration into the core enzyme, followed by in vivo test, and evaluate the stratum corneum (SC) turn-over speed.

Effect of the Hip Joint Adduction on Walking During the Plank Exercise (엉덩관절모음과 플랭크운동이 보행에 미치는 영향)

  • Mun, Dal Ju;Park, Jae Cheol;Choi, Seck Joo
    • Korean Educational Research Journal
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    • v.40 no.3
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    • pp.67-84
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    • 2019
  • The purpose of this study is to see how the stability of posture due to elastic band during plank movement affects walking. Thirty healthy men in their 20s were given a total of 30 minutes of 10 general plank exercises, 10 plank exercises with two hip joints adduction, and 10 plank exercises with one hip joint adduction. The plank movement was conducted three times a week for a total of six weeks, with a five-minute warm-up. The results of this study are as follows: There was a significant difference between period and group interactions on cadence (p<0.05), with significant difference between the period and group between the left foot on stride length of the left side foot (p<0.05), with significant difference between the period and the period of the interaction between the right foot and the period on stride length of the right side foot (p<0.05), and a one-step change between the right foot and the military interaction on Step time of the right side foot(p<0.05). The conclusion of this study is that the resistance movement on the adduction of both hips increases the instability of the trunk over the normal plank movement and adduction of one hip, thereby enhancing walking ability along with the stability of the trunk.

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Analysis of Unstable Shock-Induced Combustion over Wedges and Conical Bodies (쐐기 및 원추 주위의 불안정한 충격파 유도연소 해석)

  • Jeong-Yeol Choi
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2003.05a
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    • pp.32-33
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    • 2003
  • Mechanism of a periodic oscillation of shock-induced combustion over a two- dimensional wedges and axi-symmetric cones were investigated through a series of numerical simulations at off-attaching condition of oblique detonation waves(ODW). A same computational domain over 40 degree half-angle was considered for two-dimensional and axi-symmetric shock-induced combustion phenomena. For two-dimensional shock-induced combustion, a 2H2+02+17N2 mixture was considered at Mach number was 5.85with initial temperature 292 K and initial pressureof 12 KPa. The Rankine-Hugoniot relation has solution of attached waves at this condition. For axi-symmetric shock-induced combustion, a H2+2O2+2Ar mixture was considered at Mach number was 5.0 with initial temperature 288 K and initial pressure of 200 mmHg. The flow conditions were based on the conditions of similar experiments and numerical studies.[1, 3]Numerical simulation was carried out with a compressible fluid dynamics code with a detailed hydrogen-oxygen combustion mechanism.[4, 5] A series of calculations were carried out by changing the fluid dynamic time scale. The length wedge is varied as a simplest way of changing the fluid dynamic time scale. Result reveals that there is a chemical kinetic limit of the detached overdriven detonation wave, in addition to the theoretical limit predicted by Rankine-Hugoniot theory with equilibrium chemistry. At the off-attaching condition of ODW the shock and reaction waves still attach at a wedge as a periodically oscillating oblique shock-induced combustion, if the Rankine-Hugoniot limit of detachment isbut the chemical kinetic limit is not.Mechanism of the periodic oscillation is considered as interactions between shock and reaction waves coupled with chemical kinetic effects. There were various regimes of the periodicmotion depending on the fluid dynamic time scales. The difference between the two-dimensional and axi-symmetric simulations were distinct because the flow path is parallel and uniform behind the oblique shock waves, but is not behind the conical shock waves. The shock-induced combustion behind the conical shockwaves showed much more violent and irregular characteristics.From the investigation of characteristic chemical time, condition of the periodic instability is identified as follows; at the detaching condition of Rankine-Hugoniot theory, (1) flow residence time is smaller than the chemical characteristic time, behind the detached shock wave with heat addition, (2) flow residence time should be greater than the chemical characteristic time, behind an oblique shock wave without heat addition.

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A Study on the Current Situation of Adult Children Cohabiting with Their Parents and an Exploration of the Frame of Analysis (성인자녀의 부모 동거 현황 및 분석틀의 탐색)

  • Choi, Youn Shil
    • Journal of Families and Better Life
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    • v.32 no.4
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    • pp.75-89
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    • 2014
  • The purpose of this study is to explore whether the phenomenon of both married and unmarried adults' cohabiting with their parents in Korean society is "unilaterally parasitic" on the child's side, or is "interdependent", characterized by expectation and dependence from the parent's side. As a result of this study possessing the characteristics of theoretic research, the following propensities of parent-dependent adults have been discussed. First of all, it was discovered that the ratio of adult children dependent on and cohabiting with their parents is considerable. Second, parents cohabiting with their adult children have unfavorable sociological features, such as high age, low level of education and income, and lower standards of education and income, compared to parents in normal households. Third, it was found that parent-dependent adults in Korean society maintain a relatively high rate of financial activity and stable employment-based occupation status. Fourth, it was shown that the level of satisfaction on the relationship between parent-dependent adults and their parents was discovered to be high, which is contrastive to the prediction of negative results based on some previous researches. Single adult children's age, their level of education and financial activity status, and their parents' age and level of education were deducted as variables related to the level of satisfaction of the relationship between parents and their children. It seems that the issue of married and unmarried adults' cohabiting with their parents in Korean society should be approached from various perspectives such as political, economic, socio-cultural and developmental aspects. On the basis of this fundamental awareness and several of the materials, it is pertinent that approaches to both married and unmarried adults' cohabiting with parents in Korean society should be distinguished from approaches to those in Japanese or Western society because it reflects the uniqueness of Korean society. In the phenomenon of married and unmarried adults' cohabiting with their parents in Korean society, there are several factors besides the economic factor, especially the socio-cultural factor that have the characteristics of mutual dependence between parents and their children rather than those of unilateral parasitism, in contrast with the phenomenon in Japanese or Western society. This research was aimed to contribute by establishing basic data for policy making by providing necessary information to treat the issues of instability and anxiety related to families and reflection on the matters of generations and parent-child relationships in current Korean society.

Hybrid Control System Using On-Off Type LQG Algorithm (On-Off 형태의 LQG 알고리즘을 이용한 복합제어 시스템)

  • Jung Hyung-Jo;Yoon Woo-Hyun;Lee In-Won;Park Kyu-Sik
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.18 no.3
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    • pp.227-243
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    • 2005
  • This paper presents a hybrid control system combining lead rubber bearings and hydraulic actuators for seismic response control of a cable stayed bridge. Because multiple control devices are operating, a hybrid control system could improve the control performances. However, the overall system robustness may be impacted negatively by additional active control devices. Therefore, a secondary on-off type controller according to the responses of lead rubber bearings is combined with LQG algorithm to improve the controller robustness. Numerical simulation results show that control performances of the hybrid system controlled by an on off type LQG algorithm are improved compared to those of the passive and active control systems and are similar to those of performance oriented hybrid system controlled by a LQG algorithm with the similar peak and normed control forces. Furthermore, it is verified that the hybrid system with an on-off type LQG controller is more robust for stiffness matrix perturbation than conventional hybrid control of system, and there are no signs of instability in the overall system. The proposed control system also maintains the control performance under not only the design earthquakes but also the other earthquakes. Therefore, the hybrid control system using on-off type LQG algorithm could be proposed as an improved control strategy for seismically excited cable-stayed bridges containing many uncertainties.

Digitalization of the Nuclear Steam Generator Level Control System (증기발생기 수위조절 시스템의 디지탈화)

  • Lee, Yoon-Joon;Lee, Un-Chul
    • Nuclear Engineering and Technology
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    • v.25 no.1
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    • pp.125-135
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    • 1993
  • The safe and efficient operation of nuclear plants is recognized to be accomplished through the application of plant automation using digital technology, which is one of main targets of the next generation nuclear plants. For plant level automation, it is first required that each major subsystem be digitalized, and the steam generator water level control system is discussed in this study. The transfer functions between inputs and the level are derived by employing the thermal hydraulic model of the steam generator and are applied to the analysis of the current three-element control system. Since the control scheme in this study includes the steam generator itself as a process plant, the system order is high and the numerical instability arises in digitalizing. Together with this, the unreliability of the feedwater feedback signal at low power level leads to the proposal of a two-element control system with a proper digital controller. The digital PI controller developed for this system has the initial power adaptive gain and integration time constant. And it makes the overall system response satisfy the stability and other necessary control specifications simultaneously. Since the two-element control system using this controller depends on the initial power only, it is simple to define and it shows a similar level response behavior to that of its corresponding analog system.

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A Study on the Sufficiency of Anticipated Effect of Order Communication System Introduced to Medium-Sized Hospitals (Focused on the case of S Hospital) (중소병원의 처방전달시스템 도입효과분석에 관한 연구 (S병원의 사례를 중심으로))

  • Hong, Suk-Won;Jung, Key-Sun;Choi, Sung-Woo
    • Korea Journal of Hospital Management
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    • v.7 no.4
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    • pp.172-192
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    • 2002
  • The purpose of this study is to ascertain whether the effect of introduction of OCS(Order Communication System) to the hospital is satisfied or not comparing the anticipated effect with the actual effect. For this purpose, a domestic hospital which has introduced and has been operating OCS for several years was chosen. Based on the internal data of S Hospital prepared before introducing OCS, researcher has analyzed the basic direction, design standard and status of operation after the introduction of OCS, etc. After analyzing the status of operations of several departments using OCS and interviewing with the chiefs of pertinent departments, a survey form was designed. Actual survey and interviews were conducted by the researcher for weeks to know whether doctors, nurses, medical technicians and clerks of the patient management dept. were satisfied with OCS and to find if they have any recommendations to improve OCS. Based on the analysis of survey, the effect of OCS was evaluated whether it has satisfied the anticipated effectiveness. For the question if they feel convenient in using OCS, doctors, nursing staffs in charge of ward and the staffs of billing dept. has answered that they were all satisfied(100%). The answers for the same question were relatively high in the case of nurses in charge of outpatient and staffs of radiography. Of course, there have been some nurses and staffs who complained for the inconvenience. However, overall satisfaction was high on the average. Some common problems occurred after the introduction of OCS were frequent errors due to instability of OCS system, paralysis of function of hardware on data back-up system and redundant investment due to erroneous choice of DB program in setting DB. It was also pointed out that lack of computer education and low participation of medical staffs has resulted in failure of developing effective software. As a result, it has lowered the efficiency of OCS. For example, some works have to be done by hands even after OCS. Based on the result of this research, recommendations to maximize the effect of OCS were presented as follows. First, strong leadership of CEO and active cooperation of doctors are mandatory. Second, all the process of hospital work should be analyzed and be redesigned in more efficient ways. Third, OCS should be designed to be user-based system which can be used efficiently by all staffs of the hospital. Forth, prior to the operation of OCS, proper tests of the program and trainings of the pertinent staff are required. Fifth, prior to the selection of hardware, BMT(Bench Marking Test) should be conducted. Sixth, before introducing OCS, staffs in charge of OCS should visit many hospitals operating the OCS system and take their cases into account.

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Impaired Spindle Checkpoint Response of Brca1-deficient Mouse Embryonic Fibroblasts (MEFs) to Nocodazole Treatment (Brca1 결손 세포주에서 nocodazole 처리에 의한 spindle checkpoint 활성화 연구)

  • Kim Myoung-Ae;Kim Hyunju;Yun Jeanho
    • Journal of Life Science
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    • v.16 no.1
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    • pp.12-16
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    • 2006
  • Genetic alternation of Brca1 predispose of breast and ovarian cancer. Brca1 plays critical role in cell cycle regulation following DNA damage. Previous studies revealed that Brca1 plays an important role in S phase and G2/M checkpoint regulation. However, whether Brca1 involves in spindle checkpoint is unclear. In this study, the role of Brca1 in cell cycle response following nocodazole, which is a reagent that depolymerizes microtubules and activates the spindle checkpoint, has been examined using wild type $p53^{-/-}\;and\;p53^{-/-}Brca1^{-/-}$ mouse embryonic fibroblasts (MEFs). While wild type and Brca1-proficient MEFs showed an acute mitotic arrest, Brca1-deficient MEFs failed to arrest at mitotic phase in response to nocodazole treatment. In double-thymidine block and nocodazole treatment experiment, a portion of $p53^{-/-}\;Brca1^{-/-}$ MEFs were clearly by-passed nocodazole induced mitotic arrest. Consistent with this, in morphologic analysis, $p53^{-/-}\;Brca1^{-/-}$ MEFs showed growing cell morphology after nocodazole treatment. Taken together, these results suggest that Brca1 protein is an important component for normal induction of spindlecheckpoint and impairment of Brca1 function could induce dysregulation of mitotic cell cycle that ultimately results in genomic instability.