• Title/Summary/Keyword: Avoidance cost

Search Result 116, Processing Time 0.024 seconds

Dynamic Routing and Scheduling of Multiple AGV System (다중 무인운반차량 시스템에서의 동적 라우팅과 스케줄링)

  • 전동훈
    • Journal of the Korea Society for Simulation
    • /
    • v.8 no.3
    • /
    • pp.67-76
    • /
    • 1999
  • The study of the optimization of operating policy of AGV system, which is used in many factory automation environments has been proceeded by many researchers. The major operating policy of AGV system consists of routing and scheduling policy. AGV routing is composed with collision avoidance and minimal cost path find algorithm. To allocate jobs to the AGV system, AGV scheduling has to include AGV selection rules, parking rules, and recharging rules. Also in these rules, the key time parameters such as processing time of the device, loading/unloading time and charging time should be considered. In this research, we compare and analyze several operating policies of multiple loop-multiple AGV system by making a computer model and simulating it to present an appropriate operating policy.

  • PDF

TEN MANAGEMENT STRATEGIES TO AVOID CONSTRUCTION CONFLICTS

  • Nirmal Kumar Acharya;Young Dai Lee;Soo Yong Kim;Yong Duek Kim
    • International conference on construction engineering and project management
    • /
    • 2005.10a
    • /
    • pp.709-713
    • /
    • 2005
  • The conflict problems encountered in the construction projects led to prolonged delays in implementation, interruptions and sometimes suspension. This paper has described ten fundamental management principles to avoid conflicts in construction field and increase the productivity. They are: i) hire good (not cheap) construction professionals ii) set reasonable time and cost goals iii) recognize contractors and designers are in business to make profit iv) draft a clear contract document v) pick a suitable project delivery system vi) implement a front-end approach vii) accept construction project as a dynamic process viii) need of education and training of professionals ix) accountability and teamwork in construction site, and x) avoid negligence.

  • PDF

First Trial of Cervical Cytology in Healthy Women of Urban Laos using by Self-sampling Instrument

  • Nabandith, Viengvansay;Pholsena, Vatsana;Mounthisone, Phouthasone;Shimoe, Kyoko;Kato, Saiko;Aoki, Kunio;Noda, Sadamu;Takamatsu, Reika;Saio, Masanao;Yoshimi, Naoki
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.9
    • /
    • pp.4665-4667
    • /
    • 2012
  • Cervical cancer is the most common cancer in Laos women and a screening programme, even with the PAP smear test (PAP test), has yet to be established for routine use. The Pap test is accepted as the most appropriate for cervical cancer screening in some settings but it is not commonly available in Laos hospitals, because there are few cytopathologists and gynecologists have little experience. As a pilot program, seminars for the PAP test were given in 2007 and 2008, and then PAP tests were carried out using self-sampling instrument (Kato's device) with 200 healthy volunteers in Setthathirath hospital, Laos, in 2008. The actual examination number was 196, divided into class I 104 (53.1%), class II 85 (43.3%), class IIIa 4 (2.0%), class IIIb 1 (0.5%), and class V 1 (0.5%) by modified Papanicolau classification. Four cases had menstruation. There were 6 cases with epithelial cell abnormalities including malignancy. There were 7 cases with fungus and 2 cases with trichomonas in Class II. More than 70% volunteers felt comfortable with the Kato's device and wanted to use it next time, because of the avoidance of the embarrassment and a low cost as compared with pelvic examination by gynecologists. This first trial for PAP test for healthy Laos women related to a hospital found three percent to have abnormal cervical epithelial cells. Therefore, this appraoch using a self-sampling device suggests that it should be planned for cervical cancer prevention in Laos.

National Cultural Dimensions and their Impact on Quality Management Maturity and Project Quality Performance: Focusing on ITER Project (국가의 문화차원이 품질경영 성숙도 수준과 프로젝트 품질에 미치는 영향: ITER 프로젝트를 중심으로)

  • Hyun, Young-Jun;Song, Haegeun;Park, Young-Taek
    • Journal of Korean Society for Quality Management
    • /
    • v.45 no.2
    • /
    • pp.247-260
    • /
    • 2017
  • Purpose: The study is aimed to identify the national cultural dimensions that are affecting the quality management (QM) maturity level and the project quality performance, and analyze their relationships. Methods: This study collected the data of QM Maturity level based on Crosby's QM maturity model and the project quality performance using the Iron Triangle (Quality, Time/Schedule and Cost) from the employees who are participating in the ITER Project across the major 8 countries (China, France, Italy, Japan, Korea, Russia, U.K. and U.S.A.). Three research hypotheses are proposed concerning the national cultural dimensions in this study and Hofstede's five cultural dimensions framework are used for the statistical test. Results: The results are two folds in the study: First, there is a significant positive correlation between the QM maturity level and the project quality performance. Second, three cultural dimensions (Collectivism, Large Power Distance and Strong Uncertainty Avoidance) and five cultural dimensions (Collectivism, Large Power Distance, Strong Uncertainty Avoidance, Feminity and Long Term Orientation) have a positive impact on the QM maturity level and the project quality performance respectively. Conclusion: From the results, the understanding and consideration of the culture difference among the countries participating International Collaboration R&D project are recommended.

Reorganization of Large Purse Seine Fisheries in Korea and Japan (한국과 일본 근해선망어업의 자원이용과 어업재편에 관한 연구)

  • 김대영;김병호
    • The Journal of Fisheries Business Administration
    • /
    • v.33 no.2
    • /
    • pp.127-152
    • /
    • 2002
  • This study intends to review the development of Large Purse Seine Fisheries in Korea and Japan, and subsequent changes in the fisheries regime as well as management conditions and to examine reorganization directions. In the Northeast Asian Fishing Area, each country has done mutual operation, which causes the fishery competition and controls fishery development. Besides, Exclusive Economic Zon(EEZ) established in 1996 resulted in the prominent changes of fishery development as well as fishery relationship among each country, demands reorganization of fisheries. In the Large Purse Seine fisheries, Korea and Japan are not decreasing, they are stable. In other words, the increase in one country does not necessarily make the decrease in the other country. This is a difference from the case of the bottom fishery. Japan is the highest in the cost, the management is getting worse due to decreasing fish price and shortage of labor. In the case of Korea, the stagnant productivity has been compensated by the rising fish price, but the fishery of low productivity to cut down the size. In addition, during the 1990s the environment of fishery is getting worse because of the free import fishery, shortage of labor, etc. Following the new fisheries paradigm, each country should reorganize its fisheries structure. The principle for reorganization of fisheries structure in each country should be focused on the establishment of sustainable fisheries. The reorganization of fisheries structure for each country by EEZ establishment does not mean only dividing fishing ground and fisheries resources by countries, but means that countries should cooperate together in fisheries management for long-run benefits from fisheries.

  • PDF

Collision Avoidance and Deadlock Resolution for AGVs in an Automated Container Terminal (자동화 컨테이너 터미널에서의 AGV 충돌 방지 및 교착 해결 방안)

  • Kang, Jae-Ho;Choi, Lee;Kang, Byoung-Ho;Ryu, Kwang-Ryel;Kim, Kap-Hwan
    • Journal of Intelligence and Information Systems
    • /
    • v.11 no.3
    • /
    • pp.25-43
    • /
    • 2005
  • In modern automated container terminals, automated guided vehicle (AGV) systems are considered a viable option for the horizontal tansportation of containers between the stacking yard and the quayside cranes. AGVs in a container terminal move rather freely and do not follow fixed guide paths. For an efficient operation of such AGVs, however, a sophisticated traffic management system is required. Although the flexible routing scheme allows us to find the shortest possible routes for each of the AGVs, it may incur many coincidental encounters and path intersections of the AGVs, leading to collisions or deadlocks. However, the computational cost of perfect prediction and avoidance of deadlocks is prohibitively expensive for a real time application. In this paper, we propose a traffic control method that predicts and avoids some simple, but at the same time the most frequently occurring, cases of deadlocks between two AGVs. More complicated deadlock situations are not predicted ahead of time but detected and resolved after they occur. Our method is computationally cheap and readily applicable to real time applications. The efficiency and effectiveness of our proposed methods have been validated by simulation.

  • PDF

A Study of Path-Finding Method of Small Unmanned Aerial Vehicles for Collision Avoidance (소형 무인비행체에서의 충돌회피를 위한 비행경로 생성에 관한 연구)

  • Shin, Saebyuk;Kim, Jinbae;Kim, Shin-Dug;Kim, Cheong Ghil
    • Journal of Satellite, Information and Communications
    • /
    • v.12 no.1
    • /
    • pp.76-80
    • /
    • 2017
  • With the fast growing popularity of small UAVs (Unmanned Aerial Vehicles), recent UAV systems have been designed and utilized for the various field with their own specific purposes. UAVs are opening up many new opportunities in the fields of electronics, sensors, camera, and software for pilots. Increase in awareness and mission capabilities of UAVs are driving innovations and new applications driven with the help of low cost and its capability in undertaking high threat task. In particular, small unmanned aerial vehicles should fly in environments with high probability of unexpected sudden change or obstacle appearance in low altitude situations. In this paper, current researches regarding techniques of autonomous flight of smal UAV systems are introduced and we propose a draft idea for planning paths for small unmanned aerial vehicles in adversarial environments to arrive at the given target safely with low cost sensors.

Energy-Effective Low-Cost Small Mobile Robot Implementation for Mobile Sensor Network (모바일 센서 네트워크를 위한 에너지 효율적이고 경제적인 소형 이동 로봇의 개발)

  • Kim, Hong-Jun;Kim, Byung-Kook
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.14 no.3
    • /
    • pp.284-294
    • /
    • 2008
  • In this paper, we describe an implementation of small mobile robot that can be used at research and application of mobile sensor networking. This robot that will constitute the sensor network, as a platform of multi-robot system for each to be used as sensor node, has to satisfy restrictions in many aspects in order to perform sensing, communication protocol, and application algorithms. First, the platform must be designed with a robust structure and low power consumption since its maintenance after deployment is difficult. Second, it must have flexibility and modularity to be used effectively in any structure so that it can be used in various applications. Third, it must support the technique of wireless network for ubiquitous computing environment. At last, to let many nodes be scattered, it must be cost-effective and small. Considering the above restrictions of the mobile platform for sensor network, we designed and implemented robots control the current of actuator by using additional circuit for power efficiency. And we chose MSP430 as MCU, CC2420 as RF transceiver, and etc, that have the strength in the aspect of power. For flexibility and modularity, the platform has expansion ports. The results of experiments are described to show that this robot can act as sensor node by RF communication process with Zigbee standard protocol, execute the navigation process with simple obstacle avoidance and the moving action with RSSI(Received Signal Strength Indicator), operate at low-power, and be made with approx. $100.

Remote Cardiac Rehabilitation With Wearable Devices

  • Atsuko Nakayama;Noriko Ishii;Mami Mantani;Kazumi Samukawa;Rieko Tsuneta;Megumi Marukawa;Kayoko Ohno;Azusa Yoshida;Emiko Hasegawa;Junko Sakamoto;Kentaro Hori;Shinya Takahashi;Kaoruko Komuro;Takashi Hiruma;Ryo Abe;Togo Norimatsu;Mai Shimbo;Miyu Tajima;Mika Nagasaki;Takuya Kawahara;Mamoru Nanasato;Toshimi Ikemage;Mitsuaki Isobe
    • Korean Circulation Journal
    • /
    • v.53 no.11
    • /
    • pp.727-743
    • /
    • 2023
  • Although cardiac rehabilitation (CR) has been shown to improve exercise tolerance and prognosis in patients with cardiovascular diseases, there remains low participation in outpatient CR. This may be attributed to the patients' busy schedules and difficulty in visiting the hospital due to distance, cost, avoidance of exercise, and severity of coronary disease. To overcome these challenges, many countries are exploring the possibility of remote CR. Specifically, there is increasing attention on the development of remote CR devices, which allow transmission of vital information to the hospital via a remote CR application linked to a wearable device for telemonitoring by dedicated hospital staff. In addition, remote CR programs can support return to work after hospitalization. Previous studies have demonstrated the effects of remote CR on exercise tolerance. However, the preventive effects of remote CR on cardiac events and mortality remain controversial. Thus, safe and effective remote CR requires exercise risk stratification for each patient, telenursing by skilled staff, and multidisciplinary interventions. Therefore, quality assurance of telenursing and multi-disciplinary interventions will be essential for remote CR. Remote CR may become an important part of cardiac management in the future. However, issues such as cost-effectiveness and insurance coverage still persist.

Short-term Response of Vegetation to Cattle Grazing in an Abandoned Orchard in Southwestern Japan

  • Hayashi, K.;Ikeda, K.;Ueda, A.;Fumita, T.;Etoh, T.;Gotoh, T.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.19 no.4
    • /
    • pp.514-520
    • /
    • 2006
  • An abandoned mandarin orange orchard in southwestern Japan was set-stocked by Japanese Black cows at two stocking rates (1.0 and 2.0 animals/ha), and vegetation dynamics and diet selection by cattle were monitored for two years, in an effort to obtain information on effective use of abandoned agricultural fields for low-cost animal production and environmental conservation. Two dominant species at the commencement of grazing, kudzu (Pueraria lobata Ohwi) and tall goldenrod (Solidago altissima L.), showed different responses to grazing during the two years; the composition of kudzu decreased, contrasting with that of tall goldenrod which increased at both stocking rates. This was caused by high preference for kudzu and avoidance or low preference for tall goldenrod by cattle. Retrogression of vegetation due to cattle disturbances occurred at both stocking rates, with the high stocking rate leading to a lower degree of succession than the low stocking rate. It was shown that cattle grazing, particularly at a high stocking rate, was effective in the management of vegetation of an abandoned orchard.