• Journal of Welding and Joining
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• v.8 no.1
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• pp.31-42
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• 1990

Arc must be stable during welding first of all other factors for obtaining sound weldment, especially in the automation of welding process. Arc stability is somewhat sophisticated phenomenon which is not clearly defined yet. In consumable electrode welding, the voltage and current variation due to metal transfer enables to assess arc stability. Recently, statistical analyses of the voltage and current waveform factors are performed to assess the degress of arc stability which is assessed and controlled by operator's own experience by now. But, considering the increasing need and the trend of automation of welding process, it is necessary to monitor arc stability in real-time. In this sutdy, the modified stability index composed of two voltage and current wvaeform factors (arc time and short circuit time) reduced from four factors (arc time, short circuit time, average arc current and average short circuit current) in Mita's index by the welding electrical circuit modeling is proposed and verified by experiments to be well estimating arc stability in the static sense. Also, the recursive calculation form estimating present arc stability in the dynamic sense is developed for real-time estimation. The results of applying the recursive index during welding show good estimation of arc stability in real-time. Therefore, the results of this study offers the mean for real-time control arc stability.

• The Journal of Fisheries Business Administration
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• v.28 no.1
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• pp.85-117
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• 1997

This paper is focused on management control system. From a management control perspective, strategies should be viewed as useful, but not absolutely necessary, guides to the proper design of an MCS. When strategies are formulated more clearly, more control alternatives become feasible and it becomes easier to implement each form of management control effectively. The common and important category of controls are action controls, personnel and cultural controls, and results controls. Action controls involves ensuring that employees perform(or do not perform) certain actions that are known to be beneficial(or harmful) to the organization. Personnel and cultural controls take steps to ensure that employees will control each others' behaviors. Results controls involve rewarding individuals(and sometimes groups of individuals) for generating good outcomes or punishing them for poor outcomes. The results controls of ROI-type measure cause to make managers excessively short- term oriented, or myopic. When managers' orientations to the short - term become excessive -when the management are more concerned with short-term profit than entity value-the managers are said to be myopic. We car, solve myopic problem by introducing AR(abnormal return), near-perfect indicators of value creation. The results - control ideal would be to hold all employees accountable for the wealth they individually create(or destroy) for the owners of the entities in which they work. This ideal is approachable for top management of publicly traded corporations because for these organizations, the wealth created(returns to shareholders) can be measured directly for any period(such as a year, a quarter, or a month) as the measurement period pin(or minus) the change in the market value of the stock.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.6
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• pp.585-593
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• 2015

In the nanoscale regime, many multigate devices are explored to reduce their size further and to enhance their performance. In this paper, design of a novel device called, Triple Material Surrounding Gate Tunnel Field effect transistor (TMSGTFET) has been developed and proposed. The advantages of surrounding gate and tunnel FET are combined to form a new structure. The gate material surrounding the device is replaced by three gate materials of different work functions in order to curb the short channel effects. A 2-D analytical modeling of the surface potential, lateral electric field, vertical electric field and drain current of the device is done, and the results are discussed. A step up potential profile is obtained which screens the drain potential, thus reducing the drain control over the channel. This results in appreciable diminishing of short channel effects and hot carrier effects. The proposed model also shows improved ON current. The excellent device characteristics predicted by the model are validated using TCAD simulation, thus ensuring the accuracy of our model.

• Journal of radiological science and technology
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• v.43 no.5
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• pp.389-395
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• 2020

The evaluation of radioactivated components of heavy-ion accelerator facilities affects the safety of radiation management and the exposure dose for workers. and this is an important issue when predicting the disposal cost of waste during maintenance and dismantling of accelerator facilities. In this study, the FLUKA code was used to simulate the proton treatment device nozzle and classify the radio-nuclides and total radioactivity generated by each component over a short period of time. The source term was evaluated using NIST reference beam data, and the neutron flux generated for each component was calculated using the evaluated beam data. Radioactive isotopes caused by generated neutrons were compared and evaluated using nuclide information from the International Radiation Protection Association and the Korea Radioisotope association. Most of the nuclides produced form of beta rays and electron capture, and short-lived nuclides dominated. However, In the case of ⁵⁴Mn, which is a radioactive product of iron, the effect of gamma rays should be considered. In the case of tritium generated from a material with a low atomic number, it is considered that handling care should be taken due to its long half-life.

• The Journal of Korean Academy of Prosthodontics
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• v.33 no.1
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• pp.13-23
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• 1995

The purpose of this study is to inquire about the effects of individual tray design and impression method on the border extension and contour of denture. 10 students at the dentistry college who have normal occlusion and symmetric facial form and normal facial muscle activity were selected. The tray was designed three types (large, medium, small tray). After border molding was done by dentist and operator, final impression was taken. The length of impression body and width of border were measured by a vernier caliper on the cast. The obtained results were as follows : 1. As the tray border was shortened, the length of impression body and width of border was short (P<0.01). 2. When the impression was taken with the small tray, the length of impression body was short in passive border molding than active border molding. 3. When the medium tray was used, the width of impression body was short in passive border molding than active border molding.

• Environmental Engineering Research
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• v.15 no.1
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• pp.3-7
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• 2010

To better understand the ecology of tetrade forming organisms (TFOs) floating in a large amount of dairy wastewater treatment plant (WWTP) effluent (sequencing batch reactor [SBR]) during the inefficient phosphorus (P) removal process of an enhanced biological P removal system, the TFOs from the effluent of a full scale WWTP were separated and attempts made to culture the TFOs in presence/absence of oxygen. The intact TFOs only grew aerobically in the form of unicellular short-rods. Furthermore, to identify the intact TFOs and unicellular short-rods the DNAs of both were extracted, analyzed using their denaturing gradient gel electrophoresis (DGGE)-profiles and then sequenced. The TFOs and unicellular short-rods exhibited the same banding pattern in their DGGE-profiles, and those sequencing data resulted in their identification as Acinetobacter sp. The intact TFOs appeared in clumps and packages of tetrade cells, and were identified as Acinetobacter sp., which are known as strict aerobes and efficient P-removers. The thick layer of extracellular polymeric substance surrounding Acinetobacter sp. may inhibit phosphate uptake, and the cell morphology of TFOs might subsequently be connected with their survival strategy under the anaerobic regime of the SBR system.

• Nuclear Engineering and Technology
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• v.29 no.1
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• pp.35-44
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• 1997

Critical too-Phase flow rates of subcooled water through Short Pipes (L 140039n) with small diameters (D$\leq$7.15 min) have been experimentally investigated for wide ranges of subcooling (0~199$^{\circ}C$) and pressure (0.5~2.0 MPa). To examine the effects of various parameters (i.e., the location of flashing inception, the degree of subcooling, the stagnation temperature and pressure, and the pipe size) on the critical two-phase flow rates of subcooled water through short pipes with small diameters, a total of 135 runs were made for various combinations of test parameters using four different L/D test sections. Experimental results that show effect of various parameters on subcooled critical two phase flow rates are presented in the form of graphs such as the dimensionless mass flux ( $G^{*}$) versus the dimensionless subcooling ( $T_{sub}$$^{*}$) curve. An empirical correlation expressed in terms of a dimensionless subcooling is also obtained for subcooled two-phase flow rates through present test sections. Comparisons between the mass fluxes calculated by present correlation and a total of 755 selected experimental data points of 9 different investigators show that the agreement is fairly good except for very low subcooling data obtained from small L/D (less than 10) orifices.s.s.s.

• Steel and Composite Structures
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• v.6 no.3
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• pp.237-255
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• 2006

This paper presents a novel analytical formulation for the analysis of composite beams with partial shear interaction stiffened by a bolted longitudinal plate accounting for time effects, such as creep and shrinkage. The model is derived by means of the principle of virtual work using a displacement-based formulation. The particularity of this approach is that the partial interaction behaviour is assumed to exist between the top slab and the joist as well as between the joist and the bolted longitudinal stiffening plate, therefore leading to a three-layered structural representation. For this purpose, a novel finite element is derived and presented. Its accuracy is validated based on short-and long-term analyses for the particular cases of full shear interaction and partial shear interaction of two layers for which solutions in closed form are available in the literature. A parametric study is carried out considering different stiffening arrangements to investigate the influence on the short-and long-term behaviour of the composite beam of the shear connection stiffness between the concrete slab and the steel joist, the stiffness of the plate-to-beam connection, the properties of the longitudinal plate and the concrete properties. The values of the deflection obtained from the finite element simulations are compared against those calculated using the effective flexural rigidity in accordance with EC5 guidelines for the behaviour of elastic multi-layered beams with flexible connection and it is shown how the latter well predicts the structural response. The proposed numerical examples highlight the ease of use of the proposed approach in determining the effectiveness of different retrofitting solutions at service conditions.

• Korean Journal of Materials Research
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• v.29 no.6
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• pp.363-370
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• 2019

The recent development of information and communication technologies brings new changes to automobile traffic systems. The most typical example is the advancement of dedicated short range communication(DSRC). DSRC mainly consists of an intelligent transportation system(ITS), an electronic toll collection system(ETCS) and an advanced traveler information system(ATIS). These wireless communications often cause unnecessary electromagnetic waves, and these electromagnetic waves, in turn, cause frequent system malfunction. To solve this problem, an absorber of electromagnetic waves is suggested. In this research, various materials, such as powdered metal and iron oxides, are used to test the possibility for an effective absorption of the unnecessary electromagnetic waves. The various metal powders are made into a thin sheet form by compositing through processing. The electromagnetic characteristics(complex permittivity, complex permeability) of the fabricated sheet are measured. As a result, we achieve -6.5 dB at 940 MHz(77.6 % absorption rate) with a 1.0 mm-thickness electromagnet wave absorber, and -9.5 dB at 940 MHz(88.8 % absorption rate) with a 2.0 mm-thickness absorber.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.22 no.5
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• pp.493-499
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• 2019

Thiamine (vitamin $B_1$) is a water-soluble vitamin that is not endogenously synthesized in humans. It is absorbed by the small intestine, where it is activated. Its active form acts as a coenzyme in many energy pathways. We report a rare case of thiamine deficiency in a 3.5-year old boy with short bowel syndrome secondary to extensive bowel resection due to necrotizing enterocolitis during his neonatal age. The patient was parenteral nutrition-dependent since birth and had suffered from recurrent central catheter-related bloodstream infections. He developed confusion with disorientation and unsteady gait as well as profound strabismus due to bilateral paresis of the abductor muscle. Based on these and a very low thiamine level he was diagnosed and treated for Wernicke encephalopathy due to incomplete thiamine acquisition despite adequate administration. He fully recovered after thiamine administration. After 1999 eight more cases have been reported in the PubMed mostly of iatrogenic origin.