• Title/Summary/Keyword: Work pressure

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Performance Evaluation of Underground Pipe with In-Situ Recycled Controlled Low Strength Materials (현장발생토사 재활용 유동성채움재를 이용한 지하매설관의 거동평가)

  • Lee Kwan-Ho;Song Chang-Seob
    • International Journal of Highway Engineering
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    • v.8 no.2 s.28
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    • pp.1-12
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    • 2006
  • An existing Steel pipe, Cast iron pipe and Concrete pipe is can not escaped from aging, specially Metal tube is causing many problems that the quality of water worse is concerned about many rust and mike efficient use of preservation of water. The use of Glassfiber Reinforced Plastic Pipe(GRP PIPE) should be one of the possible scheme to get over these problems. The GRP PIPE has an excellent resistance power and the life is lasting from 50 to 100 years roughly. It's to be useful as a result of high durability and a good construction work also it is a light weight therefore can be expected to short the time of construction and man power. In this research, to executed the small-scaled model test, in-situ model test using CLSM of in-situ soil and to evaluated the stress - strain of the pipe also try to estimated how useful is. From the model test in laboratory, the vertical and horizontal deformation of the GRP PIPE measured in six instance using 200mm and 300mm in diameters. The value of experimentation, theory, analysis got the same results of the test, but the vertical and horizontal deformation gauged in small and the earth pressure was almost zero using CLSM of in-situ soil..

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A Study on Activating Police Conversational Techniques - Focusing on activation of crisis negotiation techniques - (경찰 대화기법 활성화 방안에 관한 연구 - 위기협상기법의 활성화 방안을 중심으로 -)

  • Cho, Se-Hee
    • Korean Security Journal
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    • no.54
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    • pp.149-179
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    • 2018
  • October 31, 2017, a man named Saipov who follows ISIS killed 8 people and injured nearly 20 others by driving his truck to the riverside bicycle path in Manhattan, New York, in an act of terror. June 5, 2017, the Islamic extremist Yacqub Khayre held a woman hostage in a suburb of Melbourne, Australia, before being killed by the police. Various countries around the world including the UK, France, and Germany are in war against terrorism. The terrorists change their target from hard targets such as government officials to vulnerable soft target, intensifying the public's fear, and, unlike in the past when they were organized by governments or organizations, extremists such as ISIS followers are now acting on their own in the act of terrorism. Also, as they use vehicles, pressure cooker, and other objects that can be easily found for terrorism, it is becoming more difficult for the police to prepare against terrorist attacks. Meanwhile, some terrorism researchers argue that conversational techniques (negotiation) used by the police are now of no use, as shown in the cases like 9/11 attacks in 2001 and 2016 Nice attack in France in which the suspects committed terrorist attacks without leaving enough time for the police to take action and that, therefore, tactical suppression techniques need to be developed. Therefore, this study suggested police negotiation techniques are necessary not only for terrorist attacks but also for overall police work, including handling intoxicated people at police station, and proposed ways to activate conversational techniques for police organizations.

A Case of Gitelman Syndrome Presented with Epileptic Seizure (간질 발작으로 내원하여 진단된 Gitelman 증후군 1례)

  • Park Jee-Min;Kim Jeong-Tae;Shin Jae-Il;Kim Heung-Dong;Kim Tae-Young;Cheong Hae-Il;Lee Jae-Seung
    • Childhood Kidney Diseases
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    • v.8 no.1
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    • pp.68-73
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    • 2004
  • Both Gitelman syndrome and Bartter syndrome are autosomal recessively inherited renal tubular disorders characterized by hypokalemic metabolic alkalosis, salt wasting and normal to low blood pressure. Gitelman syndrome is caused by mutations in the thiazide-sensitive Na-Cl cotransporter (NCCT) and distinguished from Bartter syndrome, which is associated with mutations of several genes, by the presence of hypomagnesemia and hypocalciuria. In most of the patients with Gitelman syndrome, the disease manifests with transient episodes of muscular weakness and tetany in the adult period, but, often, is asymptomatic. We report here an 11 years-old female with Gitelman syndrome who presented with aggravation of epileptic seizure. The diagnostic work-up showed typical clinical features of metabolic alkalosis, hypokalemia, hypomagnesemia and hypocalciuria. We also identified a heterozygote mutation($^{642}$CGC(Arg)>TGC(Cys)) and an abnormal splicing in the SLC12A3 gene encoding NCCT.

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Recurrent Neural Network Modeling of Etch Tool Data: a Preliminary for Fault Inference via Bayesian Networks

  • Nawaz, Javeria;Arshad, Muhammad Zeeshan;Park, Jin-Su;Shin, Sung-Won;Hong, Sang-Jeen
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.02a
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    • pp.239-240
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    • 2012
  • With advancements in semiconductor device technologies, manufacturing processes are getting more complex and it became more difficult to maintain tighter process control. As the number of processing step increased for fabricating complex chip structure, potential fault inducing factors are prevail and their allowable margins are continuously reduced. Therefore, one of the key to success in semiconductor manufacturing is highly accurate and fast fault detection and classification at each stage to reduce any undesired variation and identify the cause of the fault. Sensors in the equipment are used to monitor the state of the process. The idea is that whenever there is a fault in the process, it appears as some variation in the output from any of the sensors monitoring the process. These sensors may refer to information about pressure, RF power or gas flow and etc. in the equipment. By relating the data from these sensors to the process condition, any abnormality in the process can be identified, but it still holds some degree of certainty. Our hypothesis in this research is to capture the features of equipment condition data from healthy process library. We can use the health data as a reference for upcoming processes and this is made possible by mathematically modeling of the acquired data. In this work we demonstrate the use of recurrent neural network (RNN) has been used. RNN is a dynamic neural network that makes the output as a function of previous inputs. In our case we have etch equipment tool set data, consisting of 22 parameters and 9 runs. This data was first synchronized using the Dynamic Time Warping (DTW) algorithm. The synchronized data from the sensors in the form of time series is then provided to RNN which trains and restructures itself according to the input and then predicts a value, one step ahead in time, which depends on the past values of data. Eight runs of process data were used to train the network, while in order to check the performance of the network, one run was used as a test input. Next, a mean squared error based probability generating function was used to assign probability of fault in each parameter by comparing the predicted and actual values of the data. In the future we will make use of the Bayesian Networks to classify the detected faults. Bayesian Networks use directed acyclic graphs that relate different parameters through their conditional dependencies in order to find inference among them. The relationships between parameters from the data will be used to generate the structure of Bayesian Network and then posterior probability of different faults will be calculated using inference algorithms.

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Comparative analysis of two methods of laser induced boron isotopes separation

  • K.A., Lyakhov;Lee, H.J.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.407-408
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    • 2011
  • Natural boron consists of two stable isotopes 10B and 11B with natural abundance of 18.8 atom percent of 10B and 81.2 atom percent of 11B. The thermal neutron absorption cross-section for 10B and 11B are 3837 barn and 0.005 barn respectively. 10B enriched specific compounds are used for control rods and as a reactor coolant additives. In this work 2 methods for boron enrichment were analysed: 1) Gas irradiation in static conditions. Dissociation occurs due to multiphoton absorption by specific isotopes in appropriately tuned laser field. IR shifted laser pulses are usually used in combination with increasing the laser intensity also improves selectivity up to some degree. In order to prevent recombination of dissociated molecules BCl3 is mixed with H2S 2) SILARC method. Advantages of this method: a) Gas cooling is helpful to split and shrink boron isotopes absorption bands. In order to achieve better selectivity BCl3 gas has to be substantially rarefied (~0.01%-5%) in mixture with carrier gas. b) Laser intensity is lower than in the first method. Some preliminary calculations of dissociation and recombination with carrier gas molecules energetics for both methods will be demonstrated Boron separation in SILARC method can be represented as multistage process: 1) Mixture of BCl3 with carrier gas is putted in reservoir 2) Gas overcooling due to expansion through Laval nozzle 3) IR multiphoton absorption by gas irradiated by specifically tuned laser field with subsequent gradual gas condensation in outlet chamber It is planned to develop software which includes these stages. This software will rely on the following available software based on quantum molecular dynamics in external quantized field: 1) WavePacket: Each particle is treated semiclassicaly based on Wigner transform method 2) Turbomole: It is based on local density methods like density of functional methods (DFT) and its improvement- coupled clusters approach (CC) to take into account quantum correlation. These models will be used to extract information concerning kinetic coefficients, and their dependence on applied external field. Information on radiative corrections to equation of state induced by laser field which take into account possible phase transition (or crossover?) can be also revealed. This mixed phase equation of state with quantum corrections will be further used in hydrodynamical simulations. Moreover results of these hydrodynamical simulations can be compared with results of CFD calculations. The first reasonable question to ask before starting the CFD simulations is whether turbulent effects are significant or not, and how to model turbulence? The questions of laser beam parameters and outlet chamber geometry which are most optimal to make all gas volume irradiated is also discussed. Relationship between enrichment factor and stagnation pressure and temperature based on experimental data is also reported.

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Pyrolytic Reaction Pathway of Dichloromethane in Excess Hydrogen (과잉수소 반응분위기에서 Dichloromethane 열분해 반응경로에 관한 연구)

  • Won, Yang-Soo
    • Applied Chemistry for Engineering
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    • v.17 no.6
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    • pp.638-643
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    • 2006
  • Pyrolytic reaction study of dichloromethane ($CH_{2}Cl_{2}$) in excess hydrogen was performed to investigate pyrolytic reaction pathways at a pressure of 1 atm with residence times of 0.3~2.0 sec in the temperature range of $525{\sim}900^{\circ}C$. A constant feed molar ratio $CH_{2}Cl_{2}$:$H_{2}$ of 4:96 was maintained through the experiment. Reagent loss and product formation were monitored by using an on-line gas chromatograph, where batch samples were analyzed by GC/MS. Complete destruction(99%) of the parent reagent was observed at temperature near $780^{\circ}C$ with residence time over 1 sec. Major products observed were $CH_{3}Cl$, $CH_{4}$, $C_{2}H_{4}$, $C_{2}H_{6}$, and HCl. Minor products included $CHClCCl_{2}$, CHClCHCl, $CH_{2}CHCl$, and $C_{2}H_{2}$. The pyrolytic reaction pathways to describe the important features of intermediate product distributions and reagent loss, based upon thermodynamic and kinetic principles, were suggested. The results of this work provided a better understanding of pyrolytic decomposition processes which occur during the pyrolysis of $CH_{2}Cl_{2}$ and similar chlorinated methanes.

Computer Simulation of the Effect of Pressurized/Depressurized Distillation Process on the Reduction of Separation Energy of Ethanol from Alcohol Fermented Broth (가압/감압 증류 공정이 발효 알콜의 분리 에너지 절감 효과에 미치는 영향에 관한 전산 모사)

  • 허병기;배천순;김휘동
    • Journal of Energy Engineering
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    • v.2 no.1
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    • pp.123-132
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    • 1993
  • This work is focussed on the reduction of ethanol separation energy from alcohol fermented broth and categorized into the development of a computer program for the design of the pressurized/depressurized distillation process which has been regarded as one of the energy-reducing models for the conventional distillation process, the optimization of operating conditions of distillation towers by means of the developed program, and the evaluation of the total annual energy cost of pressurized/depressurized distillation columns compared with that of the conventional single distillation columns. The operating pressures are, in case of pressurized/depressurized distillation, 3103/760 mmHg, 3103/450 mmHg, 3103/160 mmHg, and in case of conventional distillation, 760 mmHg. The optimum reflex rations which the sum of the annual energy cost and the annual fixed cost for each process becomes minimum are 3.7475/2.9111 for the operating pressures of 3103/760 mmHg, 3.814/2.9712 for 3103/450 mmHg, 3.0783/2.2400 for 3103/150 mmHg, and 3.8544 for the atmospheric operating pressure. And the annual energy cost of pressurized/depressurized distillation process for the above-mentioned operating pressures is distributed between 42% and 47% of that of conventional distillation process.

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A Study on Intermediate Layer for Palladium-Based Alloy Composite Membrane Fabrication (팔라듐 합금 복합막 제조를 위한 Intermediate Layer 연구)

  • Hwang, Yong-Mook;Kim, Kwang-Je;So, Won-Wook;Moon, Sang-Jin;Lee, Kwan-Young
    • Applied Chemistry for Engineering
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    • v.17 no.5
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    • pp.458-464
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    • 2006
  • The Pd-Ni-Ag alloy composite membrane using modified porous stainless steel (PSS) as a substrate was prepared by a electroless plating technique. In this work, we have introduced the intermediate layer between Pd-based alloy and a metal substrate. As an intermediate layer, the mixtures of nickel powder and inorganic sol such as $SiO_{2}$ sol, $Al_{2}O_{3}$ sol, and $TiO_{2}$ sol were used. The intermediate layers were coated onto a PSS substrate according to various membrane preparation conditions and then $N_{2}$ fluxes through the membranes with different intermediate layers were measured. The surface morphology of the intermediate layer in the mixture of nickel powder and inorganic sol was analyzed using scanning electron microscope (SEM). Finally, the Pd-Ni-Ag alloy composite membrane using the support coated with the mixture of nickel powder and silica as an intermediate layer was fabricated and then the gas permeances for $H_{2}$ and $N_{2}$ through the Pd-based membrane were investigated. The selectivity of $H_2/N_2$ was infinite and the $H_{2}$ flux was $1.39{\times}10^{-2}mol/m^2{\cdot}s$ at the temperature of $500^{\circ}C$ and trans-membrane pressure difference of 1 bar.

A Study on the Use of Science Citation Index (SCI) and Awareness of SCI Source Journals by Faculty Members at Korean Medical Colleges (국내 의과대학 교수들의 Science Citation Index (SCI) 이용 실태 및 SCI 학술지에 대한 인지도(認知度) 조사 연구)

  • Lee Choon-Shil
    • Journal of the Korean Society for Library and Information Science
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    • v.31 no.1
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    • pp.29-52
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    • 1997
  • A questionnaire survey was conducted to investigate the use of SCI and awareness of SCI source journals by fatuity members at Korean medical colleges. 104 out of 180 faculty members randomly chosen from four prestigious medical colleges returned the questionnaires malled to them. Korean medical researchers rarely used SCI as their main source of research Information. They rather used the MEDLINE to seek the research information probably because they are easily available from their local libraries. Furthermore. many respondents mistakenly Identified 'SCI journals ranked by Impact factor' lists found In Journal Citation Reports (JCR) with the SCI Itself. That Is. In Korean medical research community. the virtue of SCI Is not as an Index but as a source of SCI Journal Impact factor Information. It Is because the Interest in impact factor Is highly associated with the pressure to publish In one of those SCI source Journals. The collected data shows that even the medical professors at these prestigious medical colleges suffer from the lack of knowledge and information about SCI. SCI source journals and their Impact factors. Nontheless, core journal titles of a medical specialty selected by Korean medical professors are mostly high-Impact Journals of Its field (1.e.. belong to the upper 1/3) zone ranked by Impact factor). Within each specialty. the Journal ranks assigned to the selected core Journals by the respondents agree with the ranks by SCI Impact factor to a great extent. That Is. the Korean medical scientists awareness on SCI Journals as defined in this study is in good standing. Therefore. a policy of a medical college to require medical professors to publish In SCI Journals to be promoted or a policy to evaluate a researcher's work by the fact that his research papers are published In SCI Journals can be positively pursued.

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Actors' Challenging Journey to Self-discoveries in Building a Character (배우의 자아발견을 향한 여정과 인물구축을 위한 도전)

  • Kim, Jun-Sam;Kim, Hak-Min
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.57-67
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    • 2012
  • There is much confusion with the relationship between character and actor. Under the pressure of 'becoming' a character, the actor tends to begin his work apart from his own senses, imagination and memory, and is most likely to fall into the trap of artificiality and clich$\acute{e}$. Like every other art, the actor has to begin honestly with himself who, in nature, has unfathomable possibilities. To be and live as a character, the actor has to experience. To experience, to react. To react, to see with all the senses. Like ours, each character's life goes on from reaction to reaction, reacting to the images from the imagination and the memory. "You are what you see." The actor is put into the extremely unfamiliar circumstances of drama, given only with his own senses, imagination and memory. Fear comes in. However, fear cannot stop the actor's challenging journey to self-discoveries. The actor does and acts, not because he is certain but because he is not. The actor challenges himself to go beyond the limit and uncertainty, so that he will finally come to know and truly understand human beings from the challenges of his own. In a nutshell, acting is a journey to the unknown and the unfamiliar in which the actor unceasingly discover new 'I's.