• Title/Summary/Keyword: Closure model

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Numerical simulation of groundwater flow in LILW Repository site:II. Input parameters for Safety Assessment (중.저준위 방사성폐기물 처분 부지의 지하수 유동에 대한 수치 모사: 2. 처분 안전성 평가 인자)

  • Park, Kyung-Woo;Ji, Sung-Hoon;Koh, Yong-Kwon;Kim, Geon-Young;Kim, Jin-Kook
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.6 no.4
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    • pp.283-296
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    • 2008
  • The numerical simulations for groundwater flow were carried out to support the input parameters for safety assessment in LILW repository site. As the input parameters for safety assessment, the groundwater flux into the underground facilities during construction, flow rate through the disposal silo after closure of disposal silo and flow pathway from the disposal silo to discharge area were analyzed using the 10 cases groundwater flow simulations. From the total 10 numerical simulation results, the statistics of estimated output were similar to among 10 cases. In some cases, the analyzed input parameters were strongly governed by locally existed high permeable fracture zone at radioactive waste disposed depth. Indeed, numerical simulation for well scenario as a human intrusion scenario was carried out using the hydraulically severe case model. Using the results of well scenario, the input parameters for safety assessment were also obtained through the numerical simulation.

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A Study on the Recent Labor-Management Dispute Cases at Medical Institutions (의료기관 노사분규 사례분석연구)

  • Shin, Gang-Wook;Yu, Seung-Hum;Kim, Young-Hoon;Kim, Tae-Woong
    • Korea Journal of Hospital Management
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    • v.14 no.1
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    • pp.123-144
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    • 2009
  • Recently, a long strike by hospital labor union emerged as a serious social issue. During the Worldcup Games in June, 2002, labor strikes broke up at 'C', 'K' and other hospitals, and in 2007, 'Y' hospital suffered much from a strike. Such series of extreme labor disputes have awakened people of importance of a more stable labor-management relationship for the medical institutions responsible for people's health than any other business organization. The purpose of this study was to examine the labor-management disputes at 'Y' hospital in 2007 and 'C' and 'K' hospitals in 2002. The results of this study can be summarized as follows; First, requests of the labor union such as pay raise, reemployment of the irregular workers as regular employees and participation of the labor union in personnel affairs are the long-held or core issues suffered by the medical institutions. Such issues are not independent from each other but complicated with each other surrounding the pay raise. Accordingly, it is not easy to determine the genuine bone of issue for labor-management disputes. Second, the model type of disputes between labor and management at medical institutions may be strike. However, it is conceived that the type of disputes would be subject to change as the essential medical service area system began to be operated since 2008. Third, the common characteristic of the labor strike among the 3 sample hospitals was occupation of the hospital lobby for a sit-in strike to maximize the negative effects of strike. Article 42 (Prohibition of Violence) of Labor Union and Labor Relation Coordination Act prohibits occupation of production or other important business facilities. In addition, since Ministry of Labor interprets that the hospital lobby belongs to the important business facilities enumerated by Article 42 of the above act, occupation of the hospital lobby for a sit-in strike may be too controversial to be admitted as a fair act of labor dispute when its legitimacy should be judged. Fourth, the counter-measures taken by the hospitals against the strike were observance of the principle 'no labor no pay,' closure, legal action, accusation, claim for recovery of damage, provisional seizure, disciplinary punishment, etc., but the principle of 'no labor, no pay' was not applied in a fair manner by 'C' and 'K' hospitals. However, 'Y' hospital applied this principle thoroughly to the strike; the hospital conduced to correction of the wrong labor-management relationship by refusing inclusion in the labor collective agreement of a provision about payment of wage during the period of strike or labor union's request to that effect during a strike. In addition, 'Y' hospital took an effective measure to end the strike earlier by notifying the labor union of cancellation of the collective agreement and banning the unionists from entering the hospital.

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The Tectono-metamorphic Evolution of Metasedimentary Rocks of the Nampo Group Outcropped in the Area of the Daecheon Beach and Maryangri, Seocheon-gun, Chungcheongnam-do (충남 대천해수욕장과 서천군 마량리 지역에 분포된 남포층군 변성퇴적암층의 변성지구조 진화)

  • Song, Yong-Sun;Choi, Jung-Youn;Park, Kye-Hun
    • The Journal of the Petrological Society of Korea
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    • v.17 no.1
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    • pp.1-15
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    • 2008
  • The metasedimentary rocks of the Nampo Croup consisting of metaconglomerates, metasandstones, phyllites are exposed in the area of the Daechcon beach and Maryangri, Seocheon-gun. Their typical metamorphic assemblages of Bt-Mus-Grt-Qtz (${\pm}Pl{\pm}Chl$) and Bt-Mus-Qtz (${\pm}Pl{\pm}Chl$) indicate that they have been under intermediate P/T type metamorphism and were metamorphosed to garnet zone grade of amphibolite-facies during the Daebo Orogeny. Pressure-temperature conditions of peak metamorphism estimated from geothermobarometries are $560{\sim}595^{\circ}C$, $6.9{\sim}8.2\;kb$ respectively. The results of K-Ar biotite age determination are $143.2{\pm}3.6\;Ma$, $122.6{\pm}2.4\;Ma$ and $124.8{\pm}2.4\;Ma$ and the last two ages are considered as the results of later-stage thermal perturbation. On the bases of the formation age of Daedong Supergroup of $187{\sim}172\;Ma$ (Han et al., 2006; Jeon et al., 2007) combined with the results of this study, the hypothetical model of tectonometamorphic evolution of the study area during Daebo Orogeny is proposed. Crustal thickening resulted from folding and duplexing of thrusts in the area initiated at around 175 Ma just after sedimentation of Nampo Croup. And then rapid cooling by normal faulting due to crustal extention followed immediately after the peak metamorphism to the closure temperature of biotite.

Numerical Investigations of Vorticity Generation in Fully Vegetated Open-Channel Flows (수치모의를 이용한 전단면 식생 수로에서의 와도 생성 분석)

  • Kang, Hyeongsik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.2B
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    • pp.179-189
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    • 2010
  • This paper presents a numerical investigation of vorticity generation in fully vegetated open-channel flows. The Reynolds stress model is used for the turbulence closure. Open-channel flows with rough bed-smooth sidewalls and smooth bed-rough sidewalls are simulated. The computed vectors show that in channel flows with rough bed and rough sidewalls, the free-surface secondary currents become relatively smaller and larger, respectively, compared with that of plain channel flows. Also, open-channel flows over vegetation are simulated. The computed bottom vortex occupies the entire water depth, while the free-surface vortex is reduced. The contours of turbulent anisotropy and Reynolds stress are presented with different density of vegetation. The budget analysis of vorticity equation is carried out to investigate the generation mechanism of secondary currents. The results of the budget analysis show that in plain open-channel flow, the production by anisotropy is important in the vicinity of the wall and free-surface boundaries, and the production by Reynolds stress is important in the region away from the boundaries. However, this rule is not effective in vegetated channel flows. Also, in plain channel flows, the vorticity is generated mainly in the vicinity of the free-surface and the bottom, while in vegetated channel flows, the regions of the bottom and vegetation height are important to generate the vorticity.

The Self-governance of the Commons and the Socio-economic Sustainability of the Jeju Haenyeo Community (제주 해녀 공동체의 공유지 관리 특성과 사회경제적 지속가능성)

  • Jong-Ho Lee;Wonseob Song;Kyung Hee Kwon;Chul-Ki Cho
    • Journal of the Economic Geographical Society of Korea
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    • v.26 no.4
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    • pp.458-476
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    • 2023
  • This study analyzes previous research on 'The Self-Governance of the Commons' to overcome 'The Tragedy of the Commons', and derives elements for successful commons management. These factors are compared and analyzed with the social and economic attributes of the Jeju Haenyeo community, a successful community self-governance model. In addition, in the recently changing environment, it is revealed whether this internal community mechanism can be useful in the future. The goal is to reveal what social and economic factors will help the sustainability of the Jeju haenyeo community in the future. As a result of analyzing the internal operating mechanism of the Jeju haenyeo community, the production and distribution system that improves trust and reciprocity, the inherent sense of community, the division of roles between formal and informal organizations, and the institutionalized explicit and implicit norms within the organization served as internal and external strengths of community sustainability. However, the closure of the network, the crisis of productivity, the weakening of homogeneity, and the emergence of new subjects acted as internal and external weaknesses. In conclusion, for the sustainability of the Jeju Haenyeo community, it is necessary to reorganize the reproductive function of labor using the haenyeo school, to maintain clarity on the subject of livelihood and cultural transmission, and guarantee the income of Haenyeo.

Generation of a transgenic mouse model to study cranial suture development; Apert syndrome (두개봉합 발육 연구를 위한 형질변환 쥐의 개발 : 어퍼트 신드롬)

  • Lee, Kee-Joon;Ratisoontorn, Chootima;Baik, Hyoung-Seon;Park, Young-Chel;Park, Kwang-Kyun;Nah, Hyun-Duck
    • The korean journal of orthodontics
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    • v.33 no.6 s.101
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    • pp.485-497
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    • 2003
  • The form and function of the craniofacial structure critically depend on genetic information. With recent advances in the molecular technology, genes that are important for normal growth and morphogenesis of the craniofacial skeleton are being rapidly uncovered, shaping up modem craniofacial biology. One of them is fibroblast growth factor receptor 2 (FGFR2). Specific point mutations in the. FGFR2 gene have been linked to Apert syndrome, which is characterized by premature closure of cranial sutures and craniofacial anomalies as well as limb deformities. To study pathogenic mechanisms underlying craniosynostosis phenotype of Apert syndrome, we used a transgenic approach; an FGFR2 minigene construct containing an Apert mutation (a point mutation that substitute proline at the position 253 to arginine; P253R) was introduced into fertilized mouse germ cells by DNA microinjection. The injected cells were then allowed to develop into transgenic mice. We used a bone-specific promoter (a DNA fragment from the type I collagen gene) to confine the expression of mutant FGFR2 gene to the bone tissue, and asked whether expression of mutant FGFR2 in bone is sufficient to cause the craniosynostosis phenotype in mice. Initial characterization of these mice shows prematurely closed cranial sutures with facial deformities expected from Apert patients. We also demonstrate that the transgene produces mutant FGFR2 protein with increased functional activities. Having this useful mouse model, we now can ask questions regarding the role of FGFR2 in normal and abnormal development of cranial bones and sutures.

A Study on the Spatial Control Effect of Panjang in Donggwoldo (동궐도(東闕圖) 판장(板墻)의 공간통제 효과에 관한 연구)

  • HA Yujeong;KIM Choongsik
    • Korean Journal of Heritage: History & Science
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    • v.55 no.4
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    • pp.196-209
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    • 2022
  • This study compared and analyzed the spatial division function and role of partitions by comparing the entire space and the spatial changes before and after the installation of partitions in <Donggwoldo>, which was manufactured in the late Joseon Dynasty. As a research method, a set standard was prepared to decompose the space of <Donggwoldo> into a unit space, and the standard was set according to the role and height of the space by classifying it into a main space, sub space, and transition space. Two convex maps were prepared according to before and after the installation of the Panjang, and the values of connectivity, control, and integration, which are spatial syntax variables, were calculated and analyzed. The results of the study are as follows. First, the partition in <Donggwoldo(東闕圖)> did not affect the overall spatial arrangement and control or connection of Donggwol, but the movement and access of space is limited to specific areas. Second, the partition was a facility intensively distributed in Naejeon(內殿) and Donggung(東宮) to be used actively in the way of space utilization. It shows that the unit space increased rapidly due to the installation of the partition. Since the partition was installed in the spaces that were open and under high control in the case of Naejeon(內殿), it helped to secure private spaces as closed ones under low control. On the other hand, for Donggung(東宮), the spaces were compartmented and divided with the partition to guide the movement path through narrow gates of the partition and increase the depth of the space. This helped to create spaces that are free and can be hidden as it increased the number of spaces coming through. Third, In addition to the functions of "eye blocking, space division, and movement path control" revealed in prior research, the partition has created a "space that is easy to control" within a specific area. The installation of the partition reduced the scale through the separation of spaces, but it occurred the expansion of the movement path and space. Also, the partition functioned to strengthen hiding and closure or increase openness as well through space division. This study is significant in that it revealed the value of the spatial control function of panjang through the analysis of spatial control and depth by analyzing the function of the partition with a mathematical model in addition to the analysis and study of the function and role of panjang. In addition, it is valuable in that it has prepared a framework for analysis tools that can be applied to traditional residential complexes similar to palaces by applying space syntax to <Donggungdo> to create convex spaces according to unit space division and connection types of palace architecture and landscape elements.

Open Heart Surgery of Congenital Heart Diseases -Report of Four Cases- (선천성심질환(先天性心疾患)의 심폐기(心肺器) 개심수술(開心手術) - 4례(例) 보고(報告) -)

  • Kim, Kun Ho;Park, Young Kwan;Jee, Heng Ok;Kim, Young Tae;Rhee, Chong Bae;Chung, Yun Chae;Oh, Chull Soo
    • Journal of Chest Surgery
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    • v.9 no.1
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    • pp.1-9
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    • 1976
  • The present. study reports four cases of congenital heart diseases, who received open heart surgery by the Sarn's Heart-Lung-Machine in the department of Thoracic Surgery, Hanyang University Hospital during the period between July 1975 and May 1976. The Heart-Lung-Machine consisted of the Sarn's five head roller pump motor system (model 5000), heat exchanger, bubble trap, the Rygg-Kyvsgaard oxygenator, and monitors. The priming of pump oxygenator was carried out by the hemodilution method using Hartman's solution and whole blood. Of the four cases of the heart diseases, three whose body weight were below 30kg, received the partial hemodilution priming and the remaining one whose body weight was 52kg received the total hemodilution priming with Hartman's solution alone. The rate of hemodilution was in the average of 60.5ml/kg. Extracorporeal circulation was performed at the perfusion flow rate of the average 94.0ml/kg/min, and at the moderate hypothermia between 35'5"C and 30'5"C of the rectal temperature. In the total cardiopulmonary bypass, arterial blood pressure was anged between 30 mmHg and 85 mmHg, generally maintaining over 60 mmHg and venous pressure was measured between 4 and $23cmH_2O$, generally maintaining below $10cmH_2O$. The first case: The patient, a nine year old girl having the symptoms and physical signs typical to cardiac anomaly was definitely diagnosed as isolated pulmonary stenosis through the cardiac catheterization. There was, however, no cyanosis, no pathological finding by X-ray and E.C.G. tracings. The valvulotomy was performed through the arteriotomy of pulmouary artery under the total cardiopulmonary bypass. Postoperative course of the patient was uneventful, and murmur and the clinical symptoms disappeared. The second case: A 12 year old boy with congenital heart anomaly was positively identified as having ventricular septal defect through the cardiac catheterization. As in the case with the first case, the patient exhibited the symptoms and physical signs typical to cardiac anomaly, but no pathological abnormality by X-ray and E.C.G. tracings. The septal defect was localized on atrioventricular canal and was 2 by 10 mm in size. The septal defect was closed by direct simple sutures under the cardiopulmonary bypass. Postoperative hemodynamic study revealed that the pressure of the right ventricle and pulmonary artery were decreased satisfactory. Postoperative course of the patient was uneventful, and murmur and the clinical symptoms disappeared. The third case: The patient, a 19 year old girl had been experienced the clinical symptoms typical to cardiac anomaly for 16 years. The pink tetralogy of Fallot was definitey diagnosed through the cardiac catheterization. The patient was placed on an ablolute bed rest prior to the operation because of severe exertional dyspnea, fatigability, and frequent syncopal attacks. However, she exhibited very slight cyanosis. Positive findings were noted on E.C.G. tracings and blood picture, but no evidence of pathological abnormality on X-ray was observed. All of the four surgical approaches such as Teflon patch closure (3 by 4cm in size) of ventricular septal defect, myocardial resection of right ventricular outflow tract, valvulotomy of pulmonary valvular stenosis, and pericardial patch closing of ventriculotomy wound were performed in 95 minutes under the cardiopulmonary bypass. Postoperative hemodynamic study revealed that the pressure of the right ventricle was decreased and pulmonary artery was increased satisfactorily. Postoperative course of the patient was uneventful, and murmur and the clinical symptoms disappeared. The fourth case: The patient, a 7 1/4 year old girl had the symptoms of cardiac anomaly for only three years prior to the operation. She was positively identified as having acyanotic tetralogy of Fallot by open heart surgery. The patient showed positive findings by X-ray and E.C.G. tracings, but exhibited no cyanosis and normal blood picture. All of the three surgical approaches, such a myocardial resection of hypertrophic sight ventricular outflow tract, direct suture closing of ventricular septal defect and pericardial patch closing of ventriculotomy wound were carried out in 110 minutes under the cardiopulmonary bypass. Postoperative hemodynamic study revealed that the pressure of the right ventricle was decreased and pulmonary artery was increased satisfactorily. Postoperative course of the patient was uneventful, and the symptoms disappeared.

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Ultrastructural analysis and quantification of autophagic vacuoles in wild-type and atg5 knockout mouse embryonic fibroblast cells (정상 및 atg5 유전자 제거 섬유아세포에서 자가포식체의 미세구조 및 이들의 정량적 분석)

  • Choi, Suin;Jeon, Pureum;Huh, Yang Hoon;Lee, Jin-A
    • Analytical Science and Technology
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    • v.31 no.5
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    • pp.208-218
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    • 2018
  • Autophagy is a cellular process whereby cytosolic materials or organelles are taken up in a double-membrane vesicle structure known as an autophagosome and transported into a lysosome for degradation. Although autophagy has been studied at the genetic, cellular, or biochemical level, systematic ultrastructural quantitative analysis of autophagosomes during the autophagy process by using transmission electron microscopy (TEM) has not yet been reported. In this study, we performed ultrastructural analysis of autophagosomes in wild-type (WT) mouse embryonic fibroblasts (MEFs) and autophagy essential gene (atg5) knockout (KO) MEFs. First, we performed ultrastructural analysis of autophagosomes in WT MEFs compared to atg5 KO MEFs in basal autophagy or starvation-induced autophagy. Although we observed phagopore, early, late autophagosomes, or autolysosomes in WT MEFs, atg5 KO MEFs had immature autophagosomes that showed incomplete closure. Upon starvation, late autophagosomes accumulated in WT MEFs while the number of immature autophagosomes significantly increased in atg5 KO MEF indicating that atg5 plays an important role in the maturation of autophagosomes. Next, we examined autophagosomes in the cell model expressing polyQ-expanded N-terminal fragment of huntingtin. Our TEM analysis indicates that the number of late autophagosomes was significantly increased in the cells expressing the mutant huntingtin, indicating that improving the fusion of autophagosome with lysosome may be effective to enhance autophagy for the treatment of Huntington's disease. Taken together, the results of our study indicate that ultrastructural and quantitative analysis of autophagosomes using TEM can be applied to various human cellular disease models, and that they will provide an important insight for cellular pathogenesis of human diseases associated with autophagy.

Numerical Analysis of Unstable Combustion Flows in Normal Injection Supersonic Combustor with a Cavity (공동이 있는 수직 분사 초음속 연소기 내의 불안정 연소유동 해석)

  • Jeong-Yeol Choi;Vigor Yang
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2003.05a
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    • pp.91-93
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    • 2003
  • A comprehensive numerical study is carried out to investigate for the understanding of the flow evolution and flame development in a supersonic combustor with normal injection of ncumally injecting hydrogen in airsupersonic flows. The formulation treats the complete conservation equations of mass, momentum, energy, and species concentration for a multi-component chemically reacting system. For the numerical simulation of supersonic combustion, multi-species Navier-Stokes equations and detailed chemistry of H2-Air is considered. It also accommodates a finite-rate chemical kinetics mechanism of hydrogen-air combustion GRI-Mech. 2.11[1], which consists of nine species and twenty-five reaction steps. Turbulence closure is achieved by means of a k-two-equation model (2). The governing equations are spatially discretized using a finite-volume approach, and temporally integrated by means of a second-order accurate implicit scheme (3-5).The supersonic combustor consists of a flat channel of 10 cm height and a fuel-injection slit of 0.1 cm width located at 10 cm downstream of the inlet. A cavity of 5 cm height and 20 cm width is installed at 15 cm downstream of the injection slit. A total of 936160 grids are used for the main-combustor flow passage, and 159161 grids for the cavity. The grids are clustered in the flow direction near the fuel injector and cavity, as well as in the vertical direction near the bottom wall. The no-slip and adiabatic conditions are assumed throughout the entire wall boundary. As a specific example, the inflow Mach number is assumed to be 3, and the temperature and pressure are 600 K and 0.1 MPa, respectively. Gaseous hydrogen at a temperature of 151.5 K is injected normal to the wall from a choked injector.A series of calculations were carried out by varying the fuel injection pressure from 0.5 to 1.5MPa. This amounts to changing the fuel mass flow rate or the overall equivalence ratio for different operating regimes. Figure 1 shows the instantaneous temperature fields in the supersonic combustor at four different conditions. The dark blue region represents the hot burned gases. At the fuel injection pressure of 0.5 MPa, the flame is stably anchored, but the flow field exhibits a high-amplitude oscillation. At the fuel injection pressure of 1.0 MPa, the Mach reflection occurs ahead of the injector. The interaction between the incoming air and the injection flow becomes much more complex, and the fuel/air mixing is strongly enhanced. The Mach reflection oscillates and results in a strong fluctuation in the combustor wall pressure. At the fuel injection pressure of 1.5MPa, the flow inside the combustor becomes nearly choked and the Mach reflection is displaced forward. The leading shock wave moves slowly toward the inlet, and eventually causes the combustor-upstart due to the thermal choking. The cavity appears to play a secondary role in driving the flow unsteadiness, in spite of its influence on the fuel/air mixing and flame evolution. Further investigation is necessary on this issue. The present study features detailed resolution of the flow and flame dynamics in the combustor, which was not typically available in most of the previous works. In particular, the oscillatory flow characteristics are captured at a scale sufficient to identify the underlying physical mechanisms. Much of the flow unsteadiness is not related to the cavity, but rather to the intrinsic unsteadiness in the flowfield, as also shown experimentally by Ben-Yakar et al. [6], The interactions between the unsteady flow and flame evolution may cause a large excursion of flow oscillation. The work appears to be the first of its kind in the numerical study of combustion oscillations in a supersonic combustor, although a similar phenomenon was previously reported experimentally. A more comprehensive discussion will be given in the final paper presented at the colloquium.

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