• International Journal of CAD/CAM
• /
• v.6 no.1
• /
• pp.29-40
• /
• 2006

The paper presents an optimization system which integrates a parametric design tool, 3D diffraction-radiation analysis and hydrodynamic performance assessment based on short and long term wave statistics. Controlled by formal optimization strategies the system is able to design offshore structure hulls with superior seakeeping qualities. The parametric modeling tool enables the designer to specify the geometric characteristics of the design from displacement over principal dimensions down to local shape properties. The computer generates the hull form and passes it on to the hydrodynamic analysis, which computes response amplitude operators (RAOs) for forces and motions. Combining the RAOs with short and long-term wave statistics provides a realistic assessment of the quality of the design. The optimization algorithm changes selected shape parameters in order to minimize forces and motions, thus increasing availability and safety of the system. Constraints ensure that only feasible designs with sufficient stability in operation and survival condition are generated. As an example the optimization study of a semisubmersible is discussed. It illustrates how offshore structures can be optimized for a specific target area of operation.

• Journal of Mechanical Science and Technology
• /
• v.14 no.10
• /
• pp.1114-1121
• /
• 2000

A flexible disk grinding process model was developed based on the dynamic relationship proposed by Kurfess and the influence of the major system parameters which potentially affect the grinding process was studied. Due to the process complexities, several new parameters were assumed to be kinematically dependent on the geometric layouts of the process. Different process stages had been defined depending on the kinematic relationships between the grinding disk and workpiece. A trend of depth of cut was simulated using the proposed model and compared with the empirically measured data in two dimensions. Due to a poor prediction capability of the first model, a modified model was proposed and a better performance has been proved to reveal a closer description of processed surface quality. Also a deflection length has been verified using a different analytical approach.

• Journal of the Korean Society for Precision Engineering
• /
• v.9 no.4
• /
• pp.78-89
• /
• 1992

The most important criteria of quality of meshing and contact of gears are the low level of noise and the sufficient dimensions and location of the contact. A new approach for determination of machine-tool settings for spiral bevel gears is proposed. The proposed settings provide a function of transmission errors, the desired location and orientation of contact. The function is able to absorb piece-wise linear functions of transmission errors that are caused by the gear misalignment and to reduce the gear noise. The determination of pinion machine-tool settings is based on the local synthesis of gears. A computer program for simulation of meshing bearing contact and determination of transmission errors for misaligned has been developed.

• Architectural research
• /
• v.17 no.4
• /
• pp.139-146
• /
• 2015

In 2007, in the city of Chongqing, the city government announced a plan to meet the basic needs of its lower-to-middle class residents, namely those of providing a shelter and urban infrastructure. In one respect, the effort to attain such goals has achieved good quantitative results; however, a more critical examination reveals that little consideration has been given to analyzing the qualitative aspects of such a policy, namely the physical and emotional effects on tenants. The results of the research in this paper have implications on the need to focus on building a 'sustainable' and 'healthy' community, with the awareness that for people in low-rent areas, sociability and community spirit are more closely related to their neighborhood contentment. Although attention to scale and type of area-planning are both important, the immediate surroundings and services are often neglected, but as we shall show they are key considerations for residents in this new type of housing. While attempting to comprehend the role of community in the quality of a neighborhood, in this research, we attempt to document the physical appearance of the problem and explore its underlying causes in order to shed more light on residents' individual evaluations of quality in their local living conditions and include the affective dimensions of such perceptions.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.115-115
• /
• 2011

Biodiesel (BD) was made from animal-fats reacting with methanol and potassium hydroxide in the laboratory. The biodiesel made in the laboratory was sent to K-petro, the government agency, to inspect the quality of animal-fats biodiesel, of which generally the quality was acceptable for heating oil for agricultural hot air heater. Kinematic viscosity and calorific values of the biodiesels were measured. BD20(K), kerosene based biodiesel, showed 18cSt at $-20^{\circ}C$. It seems that BD100 can not be suitable for heating fuel under some temperature. As BD content increased calorific value decreased, up to 40,000J/g for 100% BD, while light oil calorific value was 45,567J/g, showing difference of 5,567J/g, about 12% difference. Several different fuels, BD20, BD50, BD100 and light oil, were prepared and tested for fuel combustion qualities for agricultural hot air heater and their combustion performances were compared and analyzed. Flame dimensions of biodiesels and light oil were almost same shape at the same combustion condition in the burner of the hot air heater. Generally $CO_2$ amounts of BDs are greater than light oil. But,the differences are so small that it is hard to tell there was significant difference existed between the BDs combustion and light oil.

• The Korean Journal of Franchise Management
• /
• v.10 no.4
• /
• pp.19-29
• /
• 2019

Purpose: In beauty industry, service quality is very critical, because it impacts on the customer's positive attitude and behavior to the beauty salon or beauty brand. Thus, this research examines the effects of service attributes on customer satisfaction and loyalty in beauty salon. This research suggests the guidelines for how beauty salons should manage their physical environment, price policy, professional skills, and employees that improve management and business performance. Research design, data, and methodology: This study examines the structural relationship between service attributes, customer satisfaction, and loyalty. Service attributes divide into four sub-dimensions such as servicescape, price service, technical service, and employee service. In order to test the purposes of this research, research model and hypotheses were developed. All constructs were measured with multiple items developed and examined in previous studies. A total of 160 questionnaires were distributed and collected, and 150 were used for analysis except 10 that were unresponsive or unfaithful. The data were analyzed using SPSS 22.0 and SmartPLS 3.0 statistical package program. Result: The results of this research are as follows. First, all sub-dimensions of service attributes such as servicescape, price service, technical service, and employee service have significant positive impacts on satisfaction. Second, customer satisfaction have significant impact on loyalty. Conclusions: This study suggests an integrated model of the relationship that the characteristics of beauty salon service attributes affect customer loyalty through satisfaction, and suggests how to manage and allocate limited resources in the beauty industry. The findings of this research indicate that the level of customer satisfaction is shown to be increased by servicescape, technical characteristics, value of money, and human attributes. Thus, beauty salon management should focus on the relationship with their customers how to improve customer loyalty through satisfaction. The quality of beauty service influences customer's attitudes and behaviors toward beauty salon. Considering the beauty business, where the quality and customer satisfaction of beauty services are determined by the hairdresser's beauty skills,, the beauty salons must find ways to improve their skills and new trend of hair style. If beauty salon customers perceive the high quality of beauty service, they revisit beauty salon and recommend it to others.

• Steel and Composite Structures
• /
• v.35 no.3
• /
• pp.353-370
• /
• 2020

This paper describes a new type of replaceable fuse for moment resisting frames. Column-tree connections with beam splice connections are frequently preferred in the moment resisting frames since they eliminate field welding and provide good quality. In the column-tree connections, a part of the beam is welded to the column in the shop and the rest of the beam is bolted with the splice connection in the field. In this study, a replaceable reduced beam section (R-RBS) connection is proposed in order to eliminate welding process and facilitate assembly at the site. In the proposed R-RBS connection, one end is connected by a beam splice connection to the beam and the other end is connected by a bolted end-plate connection to the column. More importantly is that the proposed R-RBS connection allows the replacement of the damaged R-RBS easily right after an earthquake. Pursuant to this goal, experimental and numerical studies have been undertaken to investigate the performance of the R-RBS connection. An experimental study on the RBS connection was used to substantiate the numerical model using ABAQUS, a commercially available finite element software. Additionally, five different finite element models were developed to conduct a parametric study. The results of the analysis were compared in terms of the moment and energy absorption capacities, PEEQ, rupture and tri-axiality indexes. The design process as well as the optimum dimensions of the R-RBS connections are presented. It was also demonstrated that the proposed R-RBS connection satisfies AISC criteria based on the nonlinear finite element analysis results.

• Journal of the Korean earth science society
• /
• v.24 no.4
• /
• pp.273-280
• /
• 2003

The purpose of this study is to investigate the environmental perceptions of pre-service secondary school teachers about the global environment. The Subjects are 133 pre-service secondary school teachers. As an indicator of environmental perceptions, the modified New Environmental Paradigm (NEP) instrument was used. This modified NEP instrument consists of four dimensions: the negative results of growth and technology, relation of humankind and nature, quality of life, and limits of biosphere. The results of this study suggested that a majority of pre-service secondary teachers held ecological environmental perceptions. They also had a similar environmental perception to education major. However, there were significant differences in environmental perceptions and the variables of education experience on environment-related subjects. Based on the findings of this study, it is recommended that environment-related subjects. Based on the findings of this study, it is recommended that environmental education be a mandatory course in education programs.

• Journal of Power Electronics
• /
• v.18 no.6
• /
• pp.1920-1929
• /
• 2018

In order to provide a source for nine phases suitable for 18-pulse ac to dc power, this paper proposes a new structure for a step-up asymmetrical delta-connected transformer for converting three-phase ac power to nine-phase ac power. The design allows for symmetry between the nine output voltages to improve the power quality of the supply current and to minimize the THD. The results show that this new structure proves the equality between the output voltages with $40^{\circ}-{\alpha}$ and $40^{\circ}+{\alpha}$ phase shifting and produces symmetrical output currents. This result in the elimination of harmonics in the network current and provides a simulated THD that is equal to 5.12 %. An experimental prototype of the step-up asymmetrical delta-autotransformer is developed in the laboratory and the obtained results give a network current with a THD that is equal to 5.35%. Furthermore, a finite element analysis with a 3D magnetic field model is made based on the dimensions of the 4kVA, 400 V laboratory prototype three-phase with three-limb delta-autotransformer with a six-stacked-core in each limb. The magnetic distribution flux, field intensity and magnetic energy are carried out under open-circuit operation or load-loss.

• Journal of the East Asian Society of Dietary Life
• /
• v.20 no.2
• /
• pp.328-339
• /
• 2010

This study was conducted to develop a service quality measurement scale suitable for the fast food restaurant segment. After reviewing the relevant literature, it was decided that the current service quality measurement scales (SERVQUAL, SERVPERF, DINESERV) are not appropriate for the fast food restaurant segment. Based on Cronin & Taylor's (1994) argument, perceived service quality is a form of attitude that represents a long-term overall evaluation of the company. Therefore, this study selected SERVPERF items for the initial pool of service quality items. Through a systematic scale development process, the SERVPERF instrument was then refined and a new concise scale was produced. Specifically, a focus group discussion with a group of patrons who are very familiar with fast food restaurants was conducted and the new service quality measure was refined so that it would be more realistic and closely describe service operation in the fast food industry. Moreover, the data collected from 112 college students who visit fast food restaurants frequently were used to statistically evaluate each of the items again via EFA (Exploratory Factor Analysis) and three sub-dimensions were derived: (1) responsiveness, (2) tangibles, and (3) reliability. Additionally, the data collected from 179 fast food restaurant consumers was used to conduct CFA (Confirmatory Factor Analysis). During this process, the convergent validity, discriminant validity, and internal consistency were double-checked. Overall, the newly developed scale achieved validity and reliability on a theoretical and statistical basis. Possible interpretations and managerial implications are also suggested.