• Communications for Statistical Applications and Methods
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• v.31 no.4
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• pp.427-440
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• 2024

The problem addressed is that of sequentially estimating the difference between the means of two populations with respect to the squared error loss, where each population distribution is a member of the one-parameter exponential family. A Bayesian approach is adopted in which the population means are estimated by the posterior means at each stage of the sampling process and the prior distributions are not specified but have twice continuously differentiable density functions. The main result determines an asymptotic second-order lower bound, as t → ∞, for the Bayes risk of a sequential procedure that takes M observations from the first population and t - M from the second population, where M is determined according to a sequential design, and t denotes the total number of observations sampled from both populations.

• The Journal of Industrial Distribution & Business
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• v.13 no.7
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• pp.7-16
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• 2022

Purpose: The therapeutic process has various benefits since it relives most of the stresses that people are undergoing in their various working places. Thus this study will determine this process's impact on workers in their different working places. Most of the workers that are being affected by stress and use this technique are the nurses. Research design, data and methodology: The present research conducted the PRISMA process which are important in research as it provides information that individual studies cannot. Guided by a specific research question, systematic reviews collate empirical evidence that fits particular criteria to provide a summary of available evidence. Results: The findings of all fifteen investigations were reviewed, but those with the strongest evidence were given more weight. Observers should be aware that the findings on aromatherapy approaches for nurses and patients are so uniform that advice might apply to both in a high acuity workplace. Conclusions: This research concludes that with the exception of a few rare exceptions, aromatherapy is a very efficient and safe treatment that does not build up in the body, but instead is expelled via the lungs, liver and kidneys. Non-invasive aromatherapy immediately affects the brain, and anyone may give the treatment at any time or place, regardless of the location.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.5
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• pp.565-581
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• 2003

Statement of problem : A scientific examination and understanding of overall aspects of the natural dentition is the first step involved in making a satisfactory selection in the shade of an aesthetic prosthesis. Proper natural shade selection of the prosthetic restoration that is in harmony with the remaining dentition is as important aesthetically, as harmony of form and function in the anterior dentition. Clinically, the most commonly applied method of shade selection has been visual, but because of the subjective nature inherent to this method, shade selection results are variable and can be influenced by such factors as the technician, the type of shade guide used, and the type and intensity of the lighting. Purpose : The purpose of this study was to develop a more objective and scientific approach to examining and understanding the shade of teeth, which has in turn lead to the development of a number of shade analysis devices that present a more objective method of shade analysis. Material and Method : In this study, the shades of healthy anterior teeth were examined and analyzed using the recently developed digital shade analysis of the $ShadeScan^{TM}$ System. The study examined 80 individuals in their twenties, 40 males and 40 females, presenting 6 healthy, unrestored maxillary anterior teeth. Tooth brushing and oral prophylaxis were performed prior to evaluation. The ShadeScan handpiece was used to acquire images of the 6 maxillary anterior teeth. These images were analyzed using the Vita/Classical mode of the $ShadeScan^{TM}$ Software, and shade maps of each tooth were acquired and divided into cervical, middle, and incisal thirds. The shade distribution of each third, left and right symmetry, and gender differences were investigated and analyzed. Results : The results of the study are as follows : 1. An overwhelming majority of the examined teeth were found to possess shades belong to Group A, with the greatest variations occurring at the middle and cervical thirds of the maxillary central and lateral incisors, in both male and female subjects. 2. Canines of both male and female subjects showed left and right symmetry with uniform shade distribution of A4 and C4, while the lateral and central incisors showed left-right symmetry of the incisal 1/3 with a uniform shade distribution of A2 and A3 shades 3. No significant differences in shade distribution were seen between genders in maxillary canines, whereas maxillary central and lateral incisors showed differences at the middle and cervical thirds between male and female subjects The results of this study show that with the exception of maxillary canines, maxillary anterior teeth display a diverse shade distribution as well as gender differences. Conclusion : Clinically, when making a shade selection using the existing shade guide, one must consider the fact that even a single tooth consists of a variety of shades. The results of this study show that when selecting a shade from a number of groups is difficult, shades from A group are the most consistent with the natural shade or maxillary anterior teeth.

• Journal of Ocean Engineering and Technology
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• v.18 no.6 s.61
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• pp.8-15
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• 2004

Wave power distribution is investigated to determine the optimal sites for wave power generation at Jeju sea which has the highest wave energy density in the Korean coastal waters. The spatial and seasonal variation of wave power per unit length is calculated in the Jeju sea area based on the monthly mean wave data from 1979 to 2002 which is produced by the SWAN wave model simulation in prior research. The selected favorable locations for wave power generation are compared in terms of magnitude of wave energy density and distribution characteristics of wave parameters. The results suggest that Chagui-Do is the most optimal site for wave power generation in the Jeju sea. The seasonal distribution of wave energy density reveals that the highest wave energy density occurs in the northwest sea in the winter and it is dominated by wind waves, while the second highest one happens at south sea in the summer and it is dominated by a swell sea. The annual average of wave energy density shows that it gradually increases from east to west of the Jeju sea. At Chagui-Do, the energy density of the sea swell sea is relatively uniform while the energy density of the wind waves is variable and strong in the winter.

• The Journal of Asian Finance, Economics and Business
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• v.4 no.1
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• pp.59-66
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• 2017

The purpose of this paper is to review the quality of corporate governance from the prior empirical literature. This study finds that most of the researchers developed the self structured corporate governance index and few researchers used the corporate governance index provided by rating agencies. This study also finds that there is no uniform basis to measure the corporate governance quality and observed the variation in terms of overall and individual attributes of corporate governance; sub-indices of corporate governance; scoring system; weighted and un-weighted method; statistical method; time period; financial and non financial companies; code of corporate governance; listing requirement; disclosure practices; legal environment; firms characteristics; and country perspective. This study also observed that overall corporate governance quality is very low in most of the studies and even quality of corporate governance varies in the firms within the same country. This study recommends that the boundary of corporate governance quality should be defined based on the agreed set of rules and regulation, code of governance and practices. This study also suggests that the regulator and policy makers should more emphasize on code of corporate governance and regulatory framework and monitoring to improve the quality of corporate governance.

• Progress in Superconductivity
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• v.2 no.2
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• pp.76-80
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• 2001

We have fabricated YBa$_2$Cu$_3$$O_{7-x}$ (YBCO) ramp-edge Josephson junctions by modifying ramp edges of the base electrodes without depositing any artificial barrier layer. YBa$_2$Cu$_3$O/7-x//SrTiO$_3$ (YBCO/STO) films were deposited on SrTiO$_3$(100) by on-axis KrF laser deposition. After patterning the bottom YBCO/STO layer, the ramp edge was cleaned by ion-beam and then reacted with deionized water under various conditions prior to the deposition of counter-electrode layers. The top YBCO/STO layer was deposited and patterned by photolithography and ion milling. We measured current-voltage (I-V) characteristics, magnetic field modulation of the critical current at 77 K. Some showed resistively shunted junction (RSJ)-type I-V characteristics, while others exhibited flux-flow behaviors, depending on the dipping time of the ramp edge in deionized water. Junctions fabricated using optimized conditions showed fairly uniform distribution of junction parameters such as I$_{c}$R$_{n}$ values, which were about 0.16 mV at 77 K with 1$\sigma$~ 24%. We made a dc SQUID with the same deionized water treated junctions, and it showed the sinusoidal modulation under applied magnetic field at 77 K. 77 K.

• Composites Research
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• v.34 no.4
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• pp.257-263
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• 2021

Composite materials have been widely applied for fabricating pressure vessels used for storing gaseous and liquid fuel because of their high specific stiffness and specific strength. Accordingly, the accurate measurement of their mechanical property, particularly the burst pressure or fracture strain, is essential prior to the commercial release. However, verification of the safety of composite pressure vessels using conventional test methods poses some limitations because it may lead to the deformation of the load transferring media or provoke an additional energy loss that cannot be ignored. Therefore, in this study, the segment-type ring burst test device was designed considering the theoretical load transferring ratio and applicable displacement of the vertical column. Moreover, to verifying the uniform distribution of pressure of the segment type ring burst test device, the hoop stress and strain distribution of ring specimens were compared with that of the hydraulic pressure test method via FEM. To conduct a simulation of the fracture behavior of the composite pressure vessel, a Hashin failure criterion was applied to the ring specimen. Furthermore, the fracture strain was also measured from the experiment and compared with that of the result from the FEM.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.1
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• pp.53-63
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• 2016

Wheel dynamometers are used to measure dynamic load that is conveyed from the road to a vehicle while driving. In this paper, two types of six-component wheel dynamometers utilizing shear deformation and bending deformation were designed and evaluated. Prior to designing the shear and bending type wheel dynamometers, the shear and bending deformation behaviors of the basic structure of the wheel dynamometer itself were analyzed using finite element analysis. Strain analysis was performed repeatedly in order to obtain a similar output sensing strain for each load component. The design was modified with a bridge circuit in order to minimize coupling strain. The results indicated that the shear type dynamometer was expected to obtain stable characteristics due to uniform strain distribution while the bending type dynamometer was expected to obtain high-quality sensitivity performance due to consistent output sensitivity.

• Current Photovoltaic Research
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• v.2 no.1
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• pp.28-35
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• 2014

High-efficiency in $Cu(In,Ga)Se_2$ (CIGS) solar cells were usually achieved on soda-lime glass substrates due to Na incorporation that reduces deep-level defects. However, this supply of sodium from sodalime glass to CIGS through Mo back electrode could be limited at low deposition temperature. Na content could be more precisely controlled by supplying Na from known amount of an outside source. For the purpose, an $Na_2S$ layer was deposited on Mo electrode prior to CIGS film deposition and supplied to CIGS during CIGS film. With the $Na_2S$ underlayer a more uniform component distribution was possible at $350^{\circ}C$ and efficiency was improved compared to the cell without $Na_2S$ layer. With more precise control of bulk and surface component profile, CIGS film can be deposited at low temperature and could be useful for flexible CIGS solar cells.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.2
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• pp.164-171
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• 2004

Active control techniques have been used in wide areas of noise and nitration control engineering and a noise barrier is one of them. Omoto's work in 1993 would be one of the fundamental and systematic studies on the actively controlled noise barrier, in which he used equal number of control sources and error sensors. The error sensors were placed uniformly along the top edge of the noise barrier with equal distance apart and the control sources were placed in the exactly same way some distance apart from the error sensors. Since then, a couple of studies were made on the secondary sources'arrangement rather than the optimality of secondary source positions. Shao's results showed that arc shaped arrangement for secondary sources is better than the straight line one, and later work of Yang showed that the more important factor is the average distance between the primary source and secondary sources. However, since these studies were all executed with a simple uniform distribution of the secondary sources along the straight line or arc, it is difficult to conclude which arrangement is superior In order for the fare comparison. the optimality of the source positions in each arrangement must be given in prior. The primary goal of this study is focused on this aspect and some major factors were investigated and compared. The computer simulation results showed that the arc shaped arrangement is marginally better than the straight line one, and more importantly slightly tuned position can greatly improve the performance of the control system.