• Nuclear Engineering and Technology
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• 제54권1호
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• pp.162-176
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• 2022

In Lead-based reactor (LBR) severe accident, the meltdown and migration inside the reactor core will lead to fuel fragment concentration, which may further cause re-criticality and even core disintegration. Accurately predicting the migration and solidification behavior of melt in LBR severe accidents is of prime importance for safety analysis of LBR. In this study, the Moving Particle Semi-implicit (MPS) method is validated and used to simulate the migration and solidification behavior. Two main surface tension models are validated and compared. Meanwhile, the MPS method is validated by the L-plate solidification test. Based on the improved MPS method, the migration and solidification behavior of melt in LBR severe accident was studied furthermore. In the Pb-Bi coolant, the melt flows upward due to density difference. The migration and solidification behavior are greatly affected by the surface tension and viscous resistance varying with enthalpy. The whole movement process can be divided into three stages depending on the change in velocity. The heat transfer of core melt is determined jointly by two heat transfer modes: flow heat transfer and solid conductivity. Generally, the research results indicate that the MPS method has unique advantage in studying the migration and solidification behavior in LBR severe accident.

• 전자진흥
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• 제10권12호
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• pp.60-65
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• 1990

• International Journal of Ocean System Engineering
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• 제1권1호
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• pp.37-45
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• 2011

The nonlinear free-surface motions interacting with a floating body were investigated using the Moving Particle Semi-implicit (MPS) method proposed by Koshizuka and Oka [6] for incompressible flow. In the numerical method, more realistic Lagrangian moving particles were used for solving the flow field instead of the Eulerian approach with a grid system. Therefore, the convection terms and time derivatives in the Navier-Stokes equation can be calculated more directly, without any numerical diffusion, instabilities, or topological failure. The MPS method was applied to a numerical simulation of predicting the efficiency of floating-type breakwater interacting with waves.

• 한국전산유체공학회지
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• 제16권2호
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• pp.1-10
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• 2011

A new computational program, which is based on the CIP/CCUP(Constraint Interpolation Profile/CIP Combined Unified Procedure) method, has been developed to numerically analyse sloshing phenomena dealt as multiphase-flow problems. For the convection terms of Navier-Stokes equations, the RCIP(Rational function CIP) method was adopted and the THINC-WLIC(Tangent of Hyperbola for Interface Capturing-Weighted Line Interface Calculation) method was used to capture the air/water interface. To validate the present numerical method, two-dimensional dam-breaking and sloshing problems in a rectangular tank were solved by the developed method in a stationary Cartesian grid system. In the case of sloshing problems, simulations by using a improved MPS(Moving Particle Simulation) method, which is named as PNU-MPS(Pusan National University-MPS), were also carried out. The computational results are compared with those of experiments and most of the comparisons are reasonably good.

• Structural Engineering and Mechanics
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• 제47권4호
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• pp.531-544
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• 2013

Compared with pavement structures of ordinary road sections, pavement structures in the intersection are exposed to more complex traffic characteristics which may exacerbates pavement distresses such as fatigue-cracking, shoving, shear deformation and rutting. Based on a field survey about traffic characteristics in the intersection conducted in Shanghai China, a three dimensional dynamic finite-element model was developed for evaluating the mechanistic responses in the pavement structures under different traffic characteristics, namely uniform speed, acceleration and deceleration. The results from this study indicated that : (1) traffic characteristics have significant effects on the distributions of the maximum principal strain (MPS) and the maximum shear stress (MSS) at the pavement surface; (2) vehicle acceleration or deceleration substantially impact the MPS and MSS at pavement surface and could increase the magnitude of them by 20 percent to 260 percent; (3) in the vertical direction, with the increase of vehicle deceleration rate, the location of the MPS peak value and the MSS peak value changes from the sub-surface layer to the pavement surface.

• 센서학회지
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• 제28권6호
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• pp.414-419
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• 2019

An ultrasonic based magnetostrictive position sensor (MPS) provides an indication of real target position. It determines the real target position by multiplying the propagation speed of ultrasonic wave and the time-of-flight between the receiving signals; one is the initial signal by an excitation current and the other is the reflection signal by the ultrasonic wave. The propagation speed of the ultrasonic wave depends on the temperature of the waveguide. Hence, the change of the propagation speed in various environments is a critical factor in terms of the positioning accuracy in the MPS. This means that the influence of the changes in the waveguide temperature needs to be compensated. In this paper, we presents a novel way to improve the positioning accuracy of MPSs using temperature compensation for waveguide. The proposed method used the inherent measurement blind area for the structure of the MPS, which can simultaneously measure the position of the moving target and the temperature of the waveguide without any additional devices. The average positional error was approximately -23.9 mm and -1.9 mm before and after compensation, respectively. It was confirmed that the positioning accuracy was improved by approximately 93%.

• Asian Journal of Business Environment
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• 제3권1호
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• pp.23-27
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• 2013

Purpose - This study will focus on motivation of temporary workers working in distributors as well as generic companies, especially MPS (motivating potential score) proposed by job characteristics model. We think that temporary workers required intrinsic motivation in order to commit with their organization because they are difficult switch-regular workers due to glass ceiling. Research design, data, methodology - This study operates a survey targeting temporary workers, specifically, we used 144 copies except uncollected copies and dishonesty response of total 165 copies on analysis. We used multiple regression and 3 step regression to investigate the proposed model. Results - The high level of perceived distributional justice and procedural justice was increased the level of organizational commitment, respectively. And, MPS was increased the level of organizational commitment, too. Finally, this study showed that both justice and Job characteristics were very important to increase organizational commitment. Conclusions - In order to inspire temporary workers, the company provides placing enough considering job characteristics as well as fairness of the procedure and distribution. Also, to more fully understand the underlying processes between HRM (Human Resource Management) concepts, new fundamental methods may be required such as switch full-time opportunities.

• 대한유전성대사질환학회지
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• 제14권1호
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• pp.29-36
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• 2014

Mucopolysaccharidoses (MPSs) are a group of rare inherited metabolic diseases caused by deficiency of lysosomal enzymes. MPSs are clinically heterogeneous and characterized by progressive deterioration in visceral, skeletal and neurological functions. The aim of this article is to review the treatment of MPSs, the unmet needs of current treatments and vision for the future including recent clinical trials. Until recently, supportive care was the only option available for the management of MPSs. Hematopoietic stem cell transplantation (HSCT), another potentially curative treatment, is not routinely advocated in clinical practice due to its high risk profile and lack of evidence for efficacy. From the early 2000s, enzyme replacement therapy (ERT) was approved and available for the treatment of MPS I, II and VI. ERT is effective for the treatment of many somatic symptoms, particularly walking ability and respiratory function, and remains the mainstay of MPS treatment. However, no benefit was found in the neurological symptoms because the enzymes do not readily cross the blood-brain barrier (BBB). In recent years, intrathecal (IT) ERT, substrate reduction therapy (SRT) and gene therapy have been rapidly gaining greater recognition as potential therapeutic avenues. Although still under investigation, IT ERT, SRT and gene therapy are promising MPS treatments that may prevent the neurodegeneration not improved by ERT.

• Molecules and Cells
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• 제20권3호
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• pp.442-445
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• 2005

HP0894 (SwissProt/TrEMBL ID O25554) is an 88-residue conserved hypothetical protein from Helicobacter pylori strain 26695 with a calculated pI of 8.5 and a molecular weight of 10.38 kDa. Proteins with sequence similarity to HP0894 exist in Vibrio choierae, Enterococcus faecalis, Campylobacter jejuni, Streptococcus pneumoniae, Haemophilus influenzae, Escherichia coli O157, etc. Here we report the sequence-specific backbone resonance assignments of HP0894. About 97.5% (418/429) of the HN, N, CO, $C{\alpha}$, $C{\beta}$ resonances of the 88 residues of HP0894 were assigned. On the basis of these assignments, three helical regions and four strand regions were identified using the CSI program. This study is a prerequisite for calculating the solution structure of HP0894, and studying its interaction with its substrates, if any, and/or with other proteins.

• Journal of Acupuncture Research
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• 제18권4호
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• pp.201-204
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• 2001

Objective : This study was to report a clinical trial in which acupuncture treatmnt on 會陰(Huiyin, CV1) was effectively applied to a patient who had suffered from teasing pruritus ani for 38 years. pruritus ani was thought to be initiated by dystonia. Methods : The acupoint, 會陰(Huiyin, CV1) was selected, because needling on perineal muscles was mainly used to alleviate pelvic pain or pruritus ani in the light of MPS(Myofascial Pain Syndrome) theory, on which 會陰(Huiyin, CV1) was located and also had pelvic pain and pruritus ani in its indications. On the acupoint, the following maneuver was used. (1) Make a patient stand and bend forward (2) Insert a needle on 會陰(Huiyin, CV1) (3) Repeat lifting and pushing (4) Draw a needle immediately without retaining needle on the acupoint Results : The patient with Pruritus ani recovered after above treatment two times and had no recurrence up to Feb. 2001. Conclusion : In this study, Needling on 會陰(Huiyin, CV1) proved to be effective in the aspect of MPS and acupuncture treatment as well, but more clinical trials are expected to follow this study.