• Title/Summary/Keyword: Integrated Model

Search Result 5,240, Processing Time 0.04 seconds

Environmental Impact Assessment by Marine Cage Fish Farms: II. Estimation of Hydrogen Sulfide Oxidation Rate at $O_2$-H$_2$S Interface and Sulfate Reduction Rate in Anoxic Sediment Layer (해상 어류가두리양식장의 환경영향 평가: II. 가두리 양식장 퇴적물의 산소-황화수소 경계면에서 황화수소의 산화율 및 무산소 퇴적층에서 황산염 환원율 추정)

  • Lee, Jae-Seong;Kim, Kee-Hyun;Yu, Jun;Lee, Pil-Yong;Jung, Rae-Hong;Lee, Wong-Chan;Han, Jung-Jee;Lee, Yong-Hwa
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.9 no.2
    • /
    • pp.64-72
    • /
    • 2004
  • We measured the vertical profiles of $O_2$, H$_2$S, and pH in sediment pore water beneath marine cage fish farms using a microsensor with a 25 ${\mu}{\textrm}{m}$ sensor tip size. The sediments are characterized by high organic material load. The oxygen consumption, hydrogen sulfide oxidation, and sulfate reduction rates in the microzonations (derived from the vertical distribution of chemical species concentration) were estimated by adapting a simple one-dimensional diffusion-reaction model. The oxygen penetration depth was 0.75 mm. The oxic microzonations were divided into upper and lower layers. Due to hydrogen sulfide oxidation within the oxic zone, the oxygen consumption rate was higher in the lower layer. The total oxygen consumption rate integrated with reaction zone depth was estimated to be 0.092 $\mu$mol $O_2$cm$^{-2}$ hr$^{-1}$ . The total hydrogen sulfide oxidation rate occurring within 0.7 mm thickness was estimated to be 0.030 $\mu$mo1 H$_2$S cm$^{-2}$ hr$^{-1}$ , and its turnover time in the oxic sediment layer was estimated to be about 2 minutes. This suggests that hydrogen sulfide was oxidized by both chemical and microbial processes in this zone. The molar consumption ratio, calculated to be 0.84, indicates that either other electron accepters exit on hydrogen sulfide oxidation, or elemental sulfur precipitation occurs near the $O_2$- H$_2$S interface. Total sulfate reduction flux was estimated to be 0.029 $\mu$mol cm$^{-2}$ hr$^{-1}$ , which accounted for more than 60% of total $O_2$ consumption flux. This result implied that the degradation of organic matter in the anoxic layer was larger than in the oxic layer.

Evaluation of Shoreline Retreat Rate due to a Sea Level Rise using Theory of Equilibrium Beach Profile (평형해빈단면이론을 이용한 해수면 상승에 따른 해안후퇴율 산정)

  • Kang, Tae Soon;Cho, Kwangwoo;Lee, Jong Sup;Park, Won Kyung
    • Journal of Korean Society of Coastal and Ocean Engineers
    • /
    • v.26 no.4
    • /
    • pp.197-206
    • /
    • 2014
  • The purpose of this study is to evaluate coastal erosion due to a sea-level rise. The shoreline retreat rate was calculated due to future sea-level rise. Shoreline retreat rates were quantified with the cross-sectional data of 23 sandy coasts (12 sites from east coast, 5 sites from south coast, and 6 sites of west coast) and 3 cross-sectional profiles from each side of the coasts in Korea. The theory of equilibrium beach profile was employed in this study to evaluate the applicability of the theory into the coast of Korea and was tested with 15 cross-sectional beach profiles. Four scenarios of future sea level rise such as 38 cm, 59 cm, 75 cm, and 100 cm were adopted to estimate the shoreline retreat rates. Overall shoreline retreat rates for the coasts in Korea were predicted as 43.7% for 38 cm, 60.3% for 59 cm, 69.2% for 75 cm, and 80.1% for 100 cm sea level rises, respectively. Retreat rates in the east coast (29.6% for 38 cm, 45.1% for 59 cm, 56.0% for 75 cm, and 69.9% for 100 cm) showed relatively low compared to the south coast (51.9%, 67.6%, 77.2%, 87.3%) and the west coast (53.8%, 71.0%, 78.5%, 86.4%). However, all sandy coasts in Korea were assessed to be vulnerable with increasing sea-level rise. There are uncertainties in the assessment of this study, which include the limitation of the assessment model and the lack of the spatio-temporal data of the beach profiles. Therefore, this study shows that it is very important to spend integrated efforts to respond coastal erosion including comprehensive observations(monitoring) and the development of scientific understanding on the field.

The Study on the Measure to Improve the Event Place Guarding Operation System (행사장경호 운용시스템 개선방안에 관한 연구)

  • Lee, Sang-Chul;Kim, Tae-Min
    • Korean Security Journal
    • /
    • no.11
    • /
    • pp.203-226
    • /
    • 2006
  • A highly sophisticated expertise and systematic and integrated management of security operation are essential for a crowded stadium. a special object of security guarding. Nonetheless, the recent incident in a singing concert hall reveals the overall problem like the lacking safety management system. lacking deployment of professional security personnel, absence of safety manuals and safety measures, as well as the lack of professionalism of private sector security companies. In this study, we presented three categories that needed improvement, like the legal and institutional improvement, improvement of policy and improvement of operation which are required to set up the model to operate the optimal private sector security duties. For the revision of law and institution for a better and more desirable method, we discussed the revision of related laws and regulations pursuant to the security operation at places where events are held, including the revision of law on security guarding work, regulation on common housing management, uniformity of security guarding, and law on performance. For the improvement of policies, we discussed the introduction of security consultants, strengthening the security instructor system, expansion of relevant organizations, establishment of mutual cooperation, privatization of profitable events, improvement of awareness about the security activities provided by private sector, policy for the professionalism of private security operation, expansion of security exhibition and seminar. For the improvement of operation. we discussed professional security techniques. such as the technique of security consulting, the application of CPTED technique, the technique for the integration of system, the method of operation, the establishment of a system to support public security operations and volunteers, establishment of a manual for security guarding performance, modernization and high tech-oriented equipment, organization of security guarding entity in which the industry, academic society and government participates together.

  • PDF

Cloning and Transcription Analysis of Sporulation Gene (spo5) in Schizosaccharomyces pombe (Schizosaccharomyces bombe 포자형성 유전자(spo5)의 Cloning 및 전사조절)

  • 김동주
    • The Korean Journal of Food And Nutrition
    • /
    • v.15 no.2
    • /
    • pp.112-118
    • /
    • 2002
  • Sporulation in the fission yeast Schizosaccharomyces pombe has been regarded as an important model of cellular development and differentiation. S. pombe cells proliferate by mitosis and binary fission on growth medium. Deprivation of nutrients especially nitrogen sources, causes the cessation of mitosis and initiates sexual reproduction by matting between two sexually compatible cell types. Meiosis is then followed in a diploid cell in the absence of nitrogen source. DNA fragment complemented with the mutations of sporulation gene was isolated from the S. pombe gene library constructed in the vector, pDB 248' and designated as pDB(spo5)1. We futher analyzed six recombinant plasmids, pDB(spo5)2, pDB(spo5)3, pDB(spo5)4, pDB(spo5)5, pDB (spo5)6, pDB(spo5)7 and found each of these plasmids is able to rescue the spo5-2, spo5-3, spo5-4, spo5-5, spo5-6, spo5-7 mutations, respectively. Mapping of the integrated plasmid into the homologous site of the S. pombe chromosomes demonstrated that pDB(spo5)1, and pDB(spu5)Rl contained the spo5 gene. Transcripts of spo5 gene were analyzed by Northern hybridization. Two transcripts of 3.2 kb and 2.5kb were detected with 5kb Hind Ⅲ fragment containing a part of the spo5 gene as a probe. The small mRNA(2.5kb) appeared only when a wild-type strain was cultured in the absence of nitrogen source in which condition the large mRNA (3.2kb) was produced constitutively. Appearance of a 2.5kb spo5-mRNA depends upon the function of the meil, mei2 and mei3 genes.

Occupational Stress of Hospital Workers (병원종사자의 직업성 스트레스에 관한 연구 - 서울시내 500병상 이상 병원종사자를 중심으로 -)

  • Lee, Woo-Cheon
    • Korea Journal of Hospital Management
    • /
    • v.3 no.1
    • /
    • pp.1-33
    • /
    • 1998
  • The purpose of this thesis is to study theoretical access to the methods that have been used for the research of occupational stress, thereby providing management methods of occupational stress of hospital workers. With a stress model of hospital workers set up from the viewpoint of organization management, 929 sets of questionnaires were collected from intern doctors, resident doctors, nurses, nursing aides, pharmacists, medical technicians, workers in patient affairs(reception and medical insurance workers), administrators and clerks from the 8 hospitals in Seoul with more than 500 beds. Upon variance analysis, correlation analysis and regression analysis of the collected questionnaires, this work examined how differences in stress caused by specific occupations and formulated a method of stress management for the hospital workers. The results are as follows. 1) If some duties of the nurses suffering from role-overloaded stress are transferred to the nursing aides dissatisfied with insufficient role, the two grunting groups can be satisfied at the same time. It is also necessary to transfer some jobs of the overloaded workers in patient affairs to the administrators, or the other way around. To reduce stress of conflict and ambiguity of role caused by the obscure division of roles between the workers, the role of each occupation should be delineated and the clear division of roles should be translated into action strictly according to that delineated. 2) Stress of inefficiency of organization from which the student doctors suffer can be relieved by management of participation. If they have access to the process of decision-making in general hospital affairs and consequently their understanding and the autonomy of job performance are promoted, such stress will be reduced. 3) To cope with stress of career development from which nurses, medical technicians, administrators, workers in patient affairs suffer, it is necessary to establish whether they have a chance to revive their careers, whether there are any ways of remotivation for less contributive workers, and whether they encourage each other to develope their careers. If they are given a chance to develope their careers, such stress will be relieved. 4) Pharmacists, suffering from stresses of living and personal relations, have strong cohesive power among themselves and organize a well-integrated team; thereby reducing the stress of personal relations and increasing productivity. 5) For administrators and student doctors confined to lesser social supports and for nurses and workers in patient affairs whose recognition of stress and job satisfaction are affected by social supports, emotional and informational supports for job performance help alleviate an individual's mental, and physical stress. 6) In addition to the above-mentioned stress-management methods, if an organizational coping strategy is provided according to the types of stress from the general viewpoint of the whole group of hospital workers, it would be of great help to managing stress. For example, the redesign of jobs, the management of objective, the improvement of working environment, the formation of an autonomous working group and various working plans can be set up for those who suffer from stress related to inappropriate role, while career counseling and development of career process can be provided for those dissatisfied with career development. Participation in the process of decision-making and the restructuring of the organization are needed for those who suffer from stress of malfunctioning organization, whereas creation of a supportive organizational atmosphere is desired for those who feel stressed due to personal relations. As well, such organizational coping strategies. as the increase of welfare facilities, seminars and educational programs and provision of health-promotion facilities can be provided.

  • PDF

A Study on the Effects of the Institutional Pressure on the Process of Implementation and Appropriation of System: M-EMRS in Hospital Organization (시스템의 도입과 전유 과정에 영향을 미치는 제도적 압력에 관한 연구: 병원조직의 모바일 전자의무기록 시스템을 대상으로)

  • Lee, Zoon-Ky;Shin, Ho-Kyoung;Choi, Hee-Jae
    • Asia pacific journal of information systems
    • /
    • v.19 no.2
    • /
    • pp.95-116
    • /
    • 2009
  • Increasingly the institutional theory has been an important theoretical view of decision making process and IT adoption in many academic researches. This study used the institutional theory as a lens through which we can understand the factors that enable the effective appropriation of advanced information technology. It posits that mimetic, coercive, and normative pressures existing in an institutionalized environment could influence the participation of top managers or decision makers and the involvement of users toward an effective use of IT in their tasks. Since the introduction of IT, organizational members have been using IT in their daily tasks, creating and recreating rules and resources according to their own methods and needs. That is to say, the adaptation process of the IT and outcomes are different among organizations. The previous studies on a diverse use of IT refer to the appropriation of technology from the social technology view. Users appropriate IT through not only technology itself, but also in terms of how they use it or how they make the social practice in their use of it. In this study, the concepts of institutional pressure, appropriation, participation of decision makers, and involvement of users toward the appropriation are explored in the context of the appropriation of the mobile electronic medical record system (M-EMRS) in particularly a hospital setting. Based on the conceptual definition of institutional pressure, participation and involvement, operational measures are reconstructed. Furthermore, the concept of appropriation is measured in the aspect of three sub-constructs-consensus on appropriation, faithful appropriation, and attitude of use. Grounded in the relevant theories to appropriation of IT, we developed a research framework in which the effects of institutional pressure, participation and involvement on the appropriation of IT are analyzed. Within this theoretical framework, we formulated several hypotheses. We developed a second order institutional pressure and appropriation construct. After establishing its validity and reliability, we tested the hypotheses with empirical data from 101 users in 3 hospitals which had adopted and used the M-EMRS. We examined the mediating effect of the participation of decision makers and the involvement of users on the appropriation and empirically validated their relationships. The results show that the mimetic, coercive, and normative institutional pressure has an effect on the participation of decision makers and the involvement of users in the appropriation of IT while the participation of decision makers and the involvement of users have an effect on the appropriation of IT. The results also suggest that the institutional pressure and the participation of decision makers influence the involvement of users toward an appropriation of IT. Our results emphasize the mediating effect of the institutional pressure on the appropriation of IT. Namely, the higher degree of the participation of decision makers and the involvement of users, the more effective appropriation users will represent. These results provide strong support for institutional-based variables as predictors of appropriation. These findings also indicate that organizations should focus on the role of participation of decision makers and the involvement of users for the purpose of effective appropriation, and these are the practical implications of our study. The theoretical contribution of this study is lies in the integrated model of the effect of institutional pressure on the appropriation of IT. The results are consistent with the institutional theory and support previous studies on adaptive structuration theory.

Analysis of National Vertical Datum Connection Using Tidal Bench Mark (기본수준점을 이용한 국가수직기준연계 분석 연구)

  • Yoon, Ha Su;Chang, Min Chol;Choi, Yun Soo;Huh, Yong
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.22 no.3
    • /
    • pp.47-56
    • /
    • 2014
  • Recently, the velocity of sea-level rising has increased due to the global warming and the natural disasters have been occurred many times. Therefore, there are various demands for the integration of vertical reference datums for the ocean and land areas in order to develop a coastal area and prevent a natural disaster. Currently, the vertical datum for the ocean area refers to Local Mean Sea Level(LMSL) and the vertical datum for the land area is based on Incheon Mean Sea Level(IMSL). This study uses 31 points of Tidal Gauge Bench Mark (TGBM) in order to compares and analyzes the geometric heights referring LMSL, IMSL, and the nationally determined geoid surface. 11 points of comparable data are biased more than 10 cm when the geometric heights are compared. It seems to be caused by the inflow of river, the relocation of Tidal Gauge Station, and the topographic change by harbor construction. Also, this study analyze the inclination of sea surface which is the difference between IMSL and LMSL, and it shows the inclination of sea surface increases from the western to southern, and eastern seas. In this study, it is shown that TGBM can be used to integrate vertical datums for the ocean and land areas. In order to integrate the vertical datums, there need more surveying data connecting the ocean to the land area, also cooperation between Korea Hydrographic and Oceanographic Administration and National Geographic Information Institute. It is expected that the integrated vertical datum can be applied to the development of coastal area and the preventative of natural disaster.

Evaluation of Disaster Resilience Scorecard for the UN International Safety City Certification of Incheon Metropolitan City (인천시 UN 국제안전도시 인증을 위한 재난 복원력 스코어카드 평가)

  • Kim, Yong-Moon;Lee, Tae-Shik
    • Journal of Korean Society of Disaster and Security
    • /
    • v.13 no.1
    • /
    • pp.59-75
    • /
    • 2020
  • This study is a case study that applied 'UNDRR's Urban Disaster Resilience Scorecard', an evaluation tool necessary for Incheon Metropolitan City to be certified as an international safe city. I would like to present an example that the results derived from this scorecard contributed to the Incheon Metropolitan City Disaster Reduction Plan. Of course, the Disaster Resilience Scorecard can't provide a way to improve the resilience of every disaster facing the city. However, it is to find the weakness of the resilience that the city faces, and to propose a solution to reduce the city's disaster risk. This is to help practitioners to recognize the disaster risks that Incheon Metropolitan City faces. In addition, the solution recommended by UNDRR was suggested to provide resilience in areas vulnerable to disasters. It was confirmed that this process can contribute to improving the disaster resilience of Incheon Metropolitan City. UNDRR has been spreading 'Climate Change, Disaster-resistant City Creation Campaign', aka MCR (Making Cities Resilient) Campaign, to cities all over the world since 2010 to reduce global cities' disasters. By applying the disaster relief guidelines adopted by UNDRR, governments, local governments, and neighboring cities are encouraged to collaborate. As a result of this study, Incheon Metropolitan city's UN Urban Resilience Scorecard was evaluated as a strong resilience field by obtaining scores of 4 or more (4.3~5.0) in 5 of 10 essentials; 1. Prepare organization for disaster resilience and prepare for implementation, 4. Strong resilience Urban development and design pursuit, 5. Preservation of natural cushions to enhance the protection provided by natural ecosystems, 9. Ensure effective disaster preparedness and response, 10. Rapid restoration and better reconstruction. On the other hand, in the other five fields, scores of less than 4 (3.20~3.85) were obtained and evaluated as weak resilience field; 2. Analyze, understand and utilize current and future risk scenarios, 3. Strengthen financial capacity for resilience, 6. Strengthen institutional capacity for resilience, 7. Understanding and strengthening social competence for resilience, 8. Strengthen resilience of infrastructure. In addition, through this study, the risk factors faced by Incheon Metropolitan City could be identified by priority, resilience improvement measures to minimize disaster risks, urban safety-based urban development plans, available disaster reduction resources, and integrated disasters. Measures were prepared.

Electrochemical Characterization of Anti-Corrosion Film Coated Metal Conditioner Surfaces for Tungsten CMP Applications (텅스텐 화학적-기계적 연마 공정에서 부식방지막이 증착된 금속 컨디셔너 표면의 전기화학적 특성평가)

  • Cho, Byoung-Jun;Kwon, Tae-Young;Kim, Hyuk-Min;Venkatesh, Prasanna;Park, Moon-Seok;Park, Jin-Goo
    • Journal of the Microelectronics and Packaging Society
    • /
    • v.19 no.1
    • /
    • pp.61-66
    • /
    • 2012
  • Chemical Mechanical Planarization (CMP) is a polishing process used in the microelectronic fabrication industries to achieve a globally planar wafer surface for the manufacturing of integrated circuits. Pad conditioning plays an important role in the CMP process to maintain a material removal rate (MRR) and its uniformity. For metal CMP process, highly acidic slurry containing strong oxidizer is being used. It would affect the conditioner surface which normally made of metal such as Nickel and its alloy. If conditioner surface is corroded, diamonds on the conditioner surface would be fallen out from the surface. Because of this phenomenon, not only life time of conditioners is decreased, but also more scratches are generated. To protect the conditioners from corrosion, thin organic film deposition on the metal surface is suggested without requiring current conditioner manufacturing process. To prepare the anti-corrosion film on metal conditioner surface, vapor SAM (self-assembled monolayer) and FC (Fluorocarbon) -CVD (SRN-504, Sorona, Korea) films were prepared on both nickel and nickel alloy surfaces. Vapor SAM method was used for SAM deposition using both Dodecanethiol (DT) and Perfluoroctyltrichloro silane (FOTS). FC films were prepared in different thickness of 10 nm, 50 nm and 100 nm on conditioner surfaces. Electrochemical analysis such as potentiodynamic polarization and impedance, and contact angle measurements were carried out to evaluate the coating characteristics. Impedance data was analyzed by an electrical equivalent circuit model. The observed contact angle is higher than 90o after thin film deposition, which confirms that the coatings deposited on the surfaces are densely packed. The results of potentiodynamic polarization and the impedance show that modified surfaces have better performance than bare metal surfaces which could be applied to increase the life time and reliability of conditioner during W CMP.

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
    • /
    • 2003.05a
    • /
    • pp.91-93
    • /
    • 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.

  • PDF