• Journal of the Korea Computer Graphics Society
• /
• v.6 no.4
• /
• pp.23-28
• /
• 2000

We introduce a new method for constructing a dynamic Delaunay triangulation for a set S of n sites in the plane under the $L_{\infty}(L_1)$ metric. We find that the quadrant neighbor graph is contained in the Delaunay triangluation and that at least one edge of each triangle in the Delaunay triangulation is contained in the quadrant neighbor graph. By using these observations and employing a range tree scheme, we present a method that dynamically maintains the $L_{\infty}(L_1)$ Delaunay triangulation under insertions and deletions in $O(log^2n)$ amortized time and O(log n) expected time.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2023.05a
• /
• pp.123-125
• /
• 2023

4차 산업혁명의 가속화에 따라 해운 항만 산업 분야 또한 정보적 측면에서 빅 데이터에 대한 업종별 통합과 공유를 통해 연계 산업 간 산업활동 효율화를 위한 노력이 요구된다. 현재 물류 분야에 다양한 플랫폼들이 도입되고 있지만 대부분 화물운송업 또는 창고 중개업 분야에 편중되어 있다. 항만산업의 경우 코로나 펜데믹 이후 발생한 컨테이너 반입 제한 및 장치율 증가 등에 따라 운송사와 컨테이너터미널 간 갈등이 지속적으로 유발되는 상황이 발생되었다. 이에 따라 본 연구는 플랫폼을 활용한 컨테이너터미널과 운송사 간 플랫폼 개발의 필요성을 인지하고 상호 기업 간 연계 효율성을 높일 수 있는 방안을 모색하였으며 산업 관계자인 컨테이너터미널 운영사, 운송사, 포워더 업종 종사자들을 대상으로 설문지 기반 실증 분석을 수행하였다. 결과적으로 EFA를 통해 추출된 14가지 요인으로 IPA 분석을 수행한 결과 1사분면(사용 용이성, 보안성, 정보 정확성, 정보 적시성, 차량 반출/반입정보, 공컨테이너 반입/반출 정보, 풀컨테이너 반입/반출정보)으로 품질에 대한 지속적인 개선이 수행되어야 하며 2사분면(APP 시스템 품질)에 대한 고려가 종합적으로 수행되어야 함이 도출되었다. 또한, 플랫폼 개발의 주체와 이용자의 참여 유도가 필요하며 상호 이해관계자 간 효율적인 연계와 효율화를 위한 인식 구조 개선이 필요하다고 나타났다. 연구결과는 향후 컨테이너터미널과 내륙운송의 효율적인 연계를 위한 플랫폼 구축에 중대한 시사점을 제공한다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.11
• /
• pp.556-563
• /
• 2017

The purpose of this study is to verify the difference of importance-performance about human right of social worker who works in housing facilities of the disabled. Based on our result, we suggest strategies to implement human rights for the disabled. We collected data from 344 social workers in Busan. We analyzed descriptive statistics, and employed T-Test and Importance-Performance Analysis. Results found the importance level was higher than the performance level of human rights for the disabled. Second, agreement of residential space open and vote right guarantees, the importance level was higher than performance level. Items, excluding ensuring religious activities, prohibiting corporal punishment, strengthening the facility monitoring system and improve facility environment and strengthen program, featured a higher performance level than the importance level. Third, based on the IPA analysis, we derived action strategies for each IPA analysis matrix. We examined 10 items, including free communication included in the first quadrant, improvement of facilities management policy in the second quadrant, prohibition of corporal punishment and strengthening of facility monitoring system in the fourth quadrants.

• Journal of Korea Entertainment Industry Association
• /
• v.15 no.2
• /
• pp.123-135
• /
• 2021

The data processing of this study is focused on keywords related to 'Corona 19 and professional baseball' and 'Corona 19 and professional baseball no spectators', using text mining and social network analysis of textom program to identify problems and view quality. It was used to set the variable of For quantitative analysis, a questionnaire on viewing quality was constructed, and out of 270 survey respondents, 250 questionnaires were used for the final study. As a tool for securing the validity and reliability of the questionnaire, exploratory factor analysis and reliability analysis were conducted, and IPA analysis (importance-satisfaction) was conducted based on the questionnaire that secured validity and reliability, and the results and strategies were presented. As a result of IPA analysis, factors related to the image (image composition, image coloration, image clarity, image enlargement and composition, high-quality image) were found in the first quadrant, and the second quadrant was the game situation (support team game level, support player game level, star). Player discovery, competition with rival teams), game information (match schedule information, player information check, team performance and player performance, game information), interaction (consensus with the supporting team), and some factors appeared. The factors of commentator (baseball-related knowledge, communication ability, pronunciation and voice, use of standard language, introduction of game-related information) and interaction (real-time communication with the front desk, sympathy with viewers, information exchange such as chatting) appeared.

• The Journal of Engineering Geology
• /
• v.31 no.4
• /
• pp.507-522
• /
• 2021

Specific survey objectives often cannot be met using only one geophysical method, as each method's results are influenced by the specific physical properties of subsurface materials. In particular, areas susceptible to geological hazards require investigation using more than one method in order to reduce risks to life and property. Instead of analyzing the results from each method separately, this work develops a four-quadrant criterion for classifying areas of levees as safe or weak. The assessment is based on statistically determined thresholds of seismic velocity (P-wave velocity from seismic refraction and S-wave velocity from multichannel analysis of surface waves) and electrical resistivity. Thresholds are determined by subtracting the standard deviation from the mean during performance testing of this correlation technique applied to model data of four horizontal and inclined fracture zones. Compared with results from the crossplot of resistivity and P-wave velocity, crossplot analysis using resistivity and S-wave velocity data provides more reliable information on the soil type, ground stiffness, and lithological characteristics of the levee system. A loose and sandy zone (represented by low S-wave velocity and high resistivity) falling within the second quadrant is interpreted to be a weak zone. This interpretation is well supported by the N values from standard penetrating test for the central core.

• Journal of Korea Entertainment Industry Association
• /
• v.15 no.7
• /
• pp.145-158
• /
• 2021

This study is aimed at identifying the important factors required by customers through importance-satisfaction analysis of how they choose skin care shops on the basis of certain factors and attributes at this time when there is an urgent need to improve the level of quality that meets their expectations and demands in combination with the quantitative expansion of skin care shops. To achieve this, a survey was carried out to 217 people over the age of 20 in Gwangju and Jeonnam area with experience in using skin care shop services. The SPSS v. 21.0 program was used to analyze the collected data. The results are summarized as follows. IPA grid analysis of the difference in importance-satisfaction of sub-factors for skin care shop choice showed that the items corresponding to the upper-left side of maintenance and strengthening, the upper-right side of stainability, and the lower-left side of gradual improvement were the 'sanitary control of tools and products', 'basic situation(legal compliance)', and 'workers' sanitary control', 'internal control of skin care shops', 'professionalism and skills of workers'and 'quality of services', respectively. Consequently, the results of this study will be based on the efficient operation of skin care shops, and further more the utilization of them is expected to expand the quantitative and qualitative base of the skin care industry.

• 한국체육학회지인문사회과학편
• /
• v.55 no.4
• /
• pp.241-252
• /
• 2016

The purpose of this study was to suggest rating factors of the importance and the satisfaction for selecting physical education institutes for preschoolers and to provide an implication of vitalizing physical education class for preschooler with comparative analysis between importance and satisfaction using IPA analysis. 253 directors of educational institutes for preschooler have chosen through a convenience sampling method, and 430 was used for analysis. The results were as follows. First, the instructor qualification items and the program items ranked highly positions in physical education institute for preschooler. Second, the instructor qualification items, the program items, tuition items of discount benefit and institution image items of reputation had the significant difference between importance and satisfaction. Lastly, The quadrant I is "the keep up the good work" part and includes 8 items such as the expertise of the physical education teacher for preschooler. The quadrant II is "the concentrate here" part and includes 2 items such as teaching ability of the physical education teacher for preschooler. The quadrant III is "the low priority" part and includes 6 items such as reasonable prices of tuitions.

• Culinary science and hospitality research
• /
• v.15 no.3
• /
• pp.271-283
• /
• 2009

The purpose of this study is to make analyses on the importance and performance of the foodservice management, foodservice service, and the courses related to coffee in the colleges providing a coffee related curriculum, in order to determine which courses are required in the education programs for employees needed by the coffee restaurants as the employers' viewpoint. The analysis methods were frequency analysis, T-test and IPA analysis. The result are as followings. First, the performance was lower than the importance when it comes to importance and performance with the coffee related courses recognized by the staff in the coffee restaurants, particularly with a big gap in the theory of cost control and coffee theory. Second, in the IPA analysis of the importance and performance of the curriculum, quadrant - I as a weak item includes the cost control, foodservice marketing, and coffee theory courses. Quadrant - II includes the foodservice, coffee extraction practice, Espresso, Caffe Latte and Cappuccio, and Latte Art courses. Pertaining to the quadrant - III are those courses lack of the necessity, including the foodservice management, foodservice franchise, practical English in service, and coffee roasting. Quadrant - IV contains those course of less importance but of higher performance such as the practicum work experience. As part of limitations of study, specialties of staffs working for coffee franchise shops were not reflected due to lacking in pre-conducted studies and the samples couldn't be recognized to represent all coffee franchise shops since the sampling districts were restricted only to Seoul metropolitan area.

• Spatial Information Research
• /
• v.21 no.3
• /
• pp.71-78
• /
• 2013

Continuous management of bicycle facilities is needed, as uses of bicycles are increased. In the previous studies, evaluation of bicycle facilities were performed mainly from the surveys to bicycle users and experts. This study aims to evaluate the facilities for bicycle uses by setting up the quantitative assessing measures for the purpose of contributing to balanced management of the facilities for bicycle uses. Based on the existing measures provided in the previous studies about conditions for bicycles users, the variables of the facilities that are available and quantifiable were derived, and the scales of the facilities were set up. For evaluation, the station influence areas in Songpa District were selected as test areas. The methods for analysis were, first, to carry out the 'bicycle roads-facilities' analysis, which was modified from quadrant method. Consequently, individual facilities and station areas were relatively examined. Second, by principal component analysis, bicycle facilities were analyzed in a general and integrated way. From that, the variables sharing common characteristics were grouped, similar types of stations influence areas were found out, and then the groups were ranked.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.2B
• /
• pp.139-144
• /
• 2006

Using DNS data for turbulent flows in an open-channel with sidewalls, the mechanisms by which secondary flows are generated and by which Reynolds shear stresses are created, are demonstrated. Near the sidewall, secondary flows invading towards the sidewall are observed in the regions of both lower and upper corners, while secondary flows ejecting from the sidewall towards the center of the channel are created elsewhere. The distributions of Reynolds shear stresses near the sidewall are analyzed, connecting their productions with coherent structures. A quadrant analysis shows that sweeps are dominant in two corner regions where secondary flows invading towards the sidewall are generated, but that ejections are dominant in the region where secondary flows ejecting towards the center of the channel are created. Also, conditional quadrant analyses reveal that the productions of Reynolds shear stresses and the patterns of secondary flows are determined by the directional tendencies of coherent structures.