• International Journal of Fluid Machinery and Systems
• /
• v.9 no.4
• /
• pp.300-306
• /
• 2016

A twin unidirectional impulse turbine for wave energy conversion has been suggested in our previous study, and the performance under unsteady flow has been investigated by quasi-steady analysis. In the present study, the performance of twin impulse turbine under unsteady flow condition has been investigated by unsteady analysis of Computational fluid dynamics. As a result, the mean efficiency of twin unidirectional impulse turbine under unsteady flow is lower than the maximum efficiency of unidirectional impulse turbine. Moreover, it is verified that airflow goes backward in the reverse turbine in low flow rates.

• Industrial Engineering and Management Systems
• /
• v.10 no.4
• /
• pp.238-246
• /
• 2011

Given a directed graph, we can determine how the user's preference moves from one product item to another. In this graph called "preference transition network", each node represents the product item while its edge pointing to the other nodes represents the transition of user's preference. However, with the large number of items make the network become more complex, unclear and difficult to be interpreted. In order to address this problem, this paper proposes a visualization technique in preference transition analysis based on recency and frequency. By adapting these two elements, the semantic meaning of each item and its transition can be clearly identified by its different types of node size, color and edge style. The experiment in a sales data has shown the results of the proposed approach.

• International Journal of Contents
• /
• v.9 no.2
• /
• pp.22-26
• /
• 2013

Comparing online and paper-based environment for report submission and correction, the former supersedes to the latter, since (1) the turn-around time becomes shorter, (2) teaching opportunity increases, and (3) as a consequence, the student's achievement level becomes higher in the online environment. In this paper, we propose an annotation tool GABA for PDF document in order to reduce correction time by the teachers and to facilitate instruction to students. In a usual class, the same or similar assignments are given to the students. Then it is often the case that many students make similar mistakes. A teacher can register and classify common correction comments to GABA. Report correction time becomes significantly shorter by reusing the registered comments. GABA also provides various support functions in order to assist efficient checking of numerous report files such as (1) sorting of frequently-used comments, (2) similarity-based file sorting, and (3) cross tabulation of comments using category and weight.

• 한국가시화정보학회:학술대회논문집
• /
• 2002.11a
• /
• pp.43-44
• /
• 2002

A pulsed jet was measured with high-definition 3D-PTV technique. The measurement system consists of three CCD cameras, Ar-ion laser, an image grabber and a host computer. Two fitness functions were introduced in a genetic algorithm in order to enhance the correspondences of the particles. One was based on a concept of the continuum theory and the other one was based on a minimum distance error. The head vortex of the jet was visualized by LIF and was reconstructed by the constructed high-resolution 30-PTV system for comparisons.

• The Korean Journal of Nuclear Medicine
• /
• v.24 no.1
• /
• pp.1-12
• /
• 1990

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.86.6-86
• /
• 2001

For discriminating between water and oil, a novel method is proposed in this paper. As a fundamental result, the temperature dependence of ultrasonic travel time of water and oil measured from 5$^{\circ}C$ to 40$^{\circ}C$ at a step of 5$^{\circ}C$ is found as that the ultrasonic travel time of oil increases with increasing temperature, whereas that of water decreases. The proposed method for discriminating between water and oil is based on the opposite temperature dependence of ultrasonic travel time of water and oil. Besides the advantages of non-invasion and on-line measurement, there are no requirements of measuring the temperature of liquid being detected and obtaining previously a large quantity of database, and furthermore, only two times of measurements are ...

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.11a
• /
• pp.341-344
• /
• 2008

Numerical simulations have been carried out for a supersonic two-dimensional flow over open, rectangular cavities (length-to-depth ratios are L/D = 1.0) in order to investigate the effect of non-equilibrium condensation of moist air on supersonic flows around the cavity for the flow Mach number 1.83 at the cavity entrance. In the present computational investigation, a condensing flow was produced by an expansion of moist air in a Laval nozzle. The results obtained showed that in the case with non-equilibrium condensation for L/D = 1.0, amplitudes of oscillation in the cavity became smaller than those without the non-equilibrium condensation. Furthermore, the occurrence of the non-equilibrium condensation reduced the peaks of power spectrum density and the frequency of the flow field oscillation increased in comparison with the case of $S_0$ = 0.

• Asia Marketing Journal
• /
• v.17 no.3
• /
• pp.33-51
• /
• 2015

This study investigates which variables most effectively influence the positioning strategy of a brand. In addition, we test the connection between the positioning strategy of the brand and loyalty. Finally, we explore how brand experience effects the relationship between brand position and brand loyalty. To this end, this study employs the street-intercept method to collect data on consumers' perception of home appliances in Japan and conducts structural equation modeling analysis to test our hypotheses. Specifically, we find that assessments of product, service, and image have a significant impact on a brand's position which, in turn, drives brand loyalty. In addition, brand experience seems to moderate the relationship between service and brand positioning effectiveness. We also find that price promotions negatively affect brand loyalty. The research provides a consumer-centered, experiential view of how firms can develop strategies to more effectively position brands and increase loyalty among their customers. These results help both academics and practitioners to better understand how consumers assess a brand's position in the marketplace.

• American Studies
• /
• v.42 no.2
• /
• pp.57-78
• /
• 2019

The story of Lizzie Borden has served as a creative impetus in the American imagination; following the hundred years after the Borden murders, a remarkable body of creative work has been produced. Ann Schofield asserts that the Borden story has become an "ur-text for the contemplation of power, of patriarchy, [and] of sexuality" (92). In reading Mary Wilkins Freeman's "The Long Arm" (1895), this essay re-considers Schofield's claim that the Borden story and its subsequent renditions enable a revisionary take on female subjectivity and resistance to patriarchal order. More specifically, this essay examines how Freeman's text (one of the first to fictionalize the saga of Lizzie Borden) reflects back the gendered subjectivity in the in the gothic mirror for us to consider whether that reflection began as an image of subjection or that of autonomy.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.18 no.1
• /
• pp.52-56
• /
• 1985

For the fundamental studies of radiation breeding in edible marine algae, the biological effects on conchospores of Porphyra species by gamma-irradiation were examined. Two varieties, Keun-cham-gim (Porphyra tenera Kjell. form tamatsuensis Miura) and Saga No.5, were chosen for this study, and their conchospores after r-irradiation($5.0{\sim}20.0$ KR) were cultured for 50 days. The results obtained were summarized as follows. 1. Gamma-irradiation in less than the dose of 20KR did not affect germination of conchospores, and almost all spores grew into two cells germ in 24 hours after irradiation, but withering germs were gradually increased in number according to higher exposure within 5 days old culture. 2. High irradiation caused the induction of giant cells, abnormal useless growth of hold-fast, lumpish thalli and callus-like lumpy tissues. 3. The liberation of neutral spores from young germs and carpospores from mature thalli were observed on the frond exposed at $10{\sim}20$ KR irradiation. All spores were normal in division and its size. 4. The best irradiation effect on growth of Keun-cham-gim was observed at 10 KR dose, whose growth-rates were $140\%$ in wet weight and $108\%$ in mean frond area, but only $48\%$ was recorded in wet weight at 20 KR exposure. Saga No.5 were in contrast with Keun-cham-gim, and their most growth-rate was $400\%$ in wet weight ($258\%$ in frond area) at 10 KR irradiation and the worst was $20\%$ at the dose of 20 KR. 5. The withering phenomenon to death by treatment of gamma-ray presented substantial difference between two varieties. Survival rate compared with control in Keun-cham-gim was $70.7\%$ at 20 KR, but that in Saga No.5 recorded $47.0\%$ at same dose. 6. Synthesizing the results of high and low r-irradiation, it was suggested tat high r-irradiation in more than 5.0 KR inhibited conspicuously the growth of germs derived from conchospores, and about half of them withered at 15.0 KR dose or more.