• Title/Summary/Keyword: Start-up delay

Search Result 50, Processing Time 0.024 seconds

An Analysis of the Influence of Container Vehicles on the Signalized Intersection of the Roads at Pusan Port (부산항 배후도로 신호교차점에 있어서 컨테이너 차량의 영향분석)

  • 정헌영;김홍태
    • Journal of Korean Port Research
    • /
    • v.13 no.1
    • /
    • pp.87-100
    • /
    • 1999
  • This study was focused on analyzing the headway of various types of trailer in Pusan city with the high heavy vehicle rate. Then Passenger Car Equivalent(PCE) was calibrated in order to identify the impact of trailers in the traffic flow at the signalized intersections. To fulfill this goal types of trailer were classified into five categories such as full trailer semi-trailer unloaded semi-trailer semi-trailer loaded with 20ft container and semi-trailer loaded with 40ft container and Passenger Car Equivalents were identified. the Results are as follows: 1) The PCE’s were 2.64, 1.51, 2.09, 2.16 and 2.23 respectively. 2) The saturation flow rate on the signalized intersection was lower than that on the multi-lane highway in the big city of Korea. 3) The start-up delay on the thru lane was similar to the average value in our country but the start-up delay on the left-turn lane was longer than the average value in our country by the impact of container Vehicles.

  • PDF

The study of proton exchange membrane fuel cell and Li-poly battery hybrid system (로봇용 연료전지 이차전지 하이브리드 시스템 연구)

  • Kwon, O-Sung;Lee, Sang-Cheol;Lee, Sang-Woo;Lee, Dong-Ha
    • Journal of the Korean Solar Energy Society
    • /
    • v.32 no.spc3
    • /
    • pp.282-288
    • /
    • 2012
  • Proton exchange membrane fuel cell (PEMFC) is the most promising energy source for the robot applications because it has unique advantages such as high energy density, no power drop during operating, and easy to make compact size. However, PEMFC has intrinsic disadvantages which are delay to start up and difficulty to correspond drastic load changes. These disadvantages can be compensated by hybrid operating with a Li-poly battery. This study is focus to build and understand the hybrid system for the robot system. In this study, we build the PEMFC hybrid system using EOS-320 PEMFC stack, Li-poly battery and G-Philos FDX1-250BU dc-dc converter. The hybrid system is accurately monitored by CAN and RS485. The system was studied under two conditions such as non-loaded and loaded operating conditions. The results show that the system has delay to start up without hybrid operating and it can be compensated with the hybrid operating.

The study of proton exchange membrane fuel cell and Li-poly battery hybrid system (로봇용 연료전지 이차전지 하이브리드 시스템 개발)

  • Kwon, O-Sung;Lee, Sang-Cheol;Lee, Sang-Woo;Lee, Dong-Ha
    • 한국태양에너지학회:학술대회논문집
    • /
    • 2012.03a
    • /
    • pp.229-233
    • /
    • 2012
  • Proton exchange membrane fuel cell (PEMFC) is the most promising energy source for the robot applications because it has unique advantages such as high energy density, no power drop during operating, and easy to make compact size. However, PEMFC has intrinsic disadvantages which are delay to start up and difficulty to correspond drastic load changes. These disadvantages can be compensated by hybrid operating with a Li-poly battery. This study is focus to build and understand the hybrid system for the robot system. In this study, we build the PEMFC hybrid system using EOS-320 PEMFC stack, Li-poly battery and G-Philos FDX1-250BU dc-dc converter. The hybrid system is accurately monitored by CAN and RS485. The system was studied under two conditions such as non-loaded and loaded operating conditions. The results show that the system has delay to start up without hybrid operating and it can be compensated with the hybrid operating.

  • PDF

Determination of Optimal Traffic Signal Cycle using Neural Network (신경망을 이용한 최적 교통신호주기 결정)

  • 홍유식;박종국
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.6 no.3
    • /
    • pp.51-62
    • /
    • 1996
  • Electro sensitive traffic system can not consider passenger car unit, so it causes start up delay time and passenger waiting time. In this paper, it antecedently creates passenger car unit at the bottom intersection using neural network. But, sometimes it can make mistakes due to changes in car weight, car speed, and passing area. Therefore, it consequently reduces the car waiting time and start-up delay time using fuzzy control of feed-back data. Moreover, to prevent spillback, it can adapt control even though upper traffic intersection has a different saturation rate, road length, road slope and road width.

  • PDF

Effect on Vibration of Start-up Condition and Retrofit of Steam Turbines (증기터빈의 기동조건과 성능개선이 터빈의 진동에 미치는 영향)

  • Lee, Hyuk Soon;Chung, Hyuk Jin;Song, Woo Sok
    • Transactions of the Korean Society of Pressure Vessels and Piping
    • /
    • v.7 no.3
    • /
    • pp.1-7
    • /
    • 2011
  • The analysis shows that the vibration is one of the main reasons of turbine failure. Especially, the problems caused by vibration occur right after retrofit of the turbine-generator and restarting the turbine. Through the case study of high vibration caused by after the turbine trip and restart, turbine vibration was identified to be influenced by startup condition. Turbine startup at high casing temperature right after unscheduled turbine trip cause radial expansion in rotor by contraction in axial direction, while casing continues to contract by steam flowing into casing. Consequently, gap between rotor and casing decrease until to metal contact to cause high vibration. Through the case study of high vibration of turbine-generator system after generator retrofit, it was identified that generator replacement could cause high vibration in turbine-generator system if the influence of generator replacement on entire system was not considered properly. To prevent startup delay caused by high vibration, it is important to keep the gaps at the design standard and start the turbine after thermal equilibrium.

A Start-Time Based Fair Packet Scheduler Supporting Multiple Delay Bounds (다수 지연규격을 지원하는 시작시각 기반 공정패킷 스케줄러)

  • Kim Tae-Joon
    • Journal of Korea Multimedia Society
    • /
    • v.9 no.3
    • /
    • pp.323-332
    • /
    • 2006
  • Fair packet scheduling algorithms supporting quality-of-services of real-time multimedia applications can be classified into the following two schemes in terms of the reference time used in calculating the timestamp of arriving packet; the Finish-Time (FT) and Start-Time (ST) schemes. The FT scheme, used in most schedulers, that has the property of an inversely rate-proportional latency is suitable to support various delay bounds because it can adjust the latency of a flow with raising the flow's reserved rate. However, the scheme may incur some bandwidth loss due to excess rate reservation. Meanwhile, although the ST scheme does not suffer from the bandwidth loss, it is hard to support multiple delay bounds because of its latency property relying on the number of flows. This paper is devoted to propose a ST scheme based scheduler to effectively support multiple delay bounds and analyze its performance comparing to the FT scheme based scheduler. The comparison results show that the proposed scheduler gives better utilization by up to 50%.

  • PDF

Developmental profiles of preschool children with delayed language development

  • Eun, Jeong Ji;Lee, Hyung Jik;Kim, Jin Kyung
    • Clinical and Experimental Pediatrics
    • /
    • v.57 no.8
    • /
    • pp.363-369
    • /
    • 2014
  • Purpose: This study examines changes in developmental profiles of children with language delay over time and the clinical significance of assessment conducted at age 2-3 years. Methods: We retrospectively reviewed the medical records of 70 children (62 male, 8 female), who had visited the hospital because of delayed language development at 2-3 years, and were reassessed at ages 5-6. Language and cognitive abilities were assessed using multiple scales at the initial and follow-up visits. Results: At the initial test, 62 of the 70 children had mental development index (MDI) below 70 of Bayley Scales of Infant Development Test II. Of the 62 children in the follow-up assessment, 30 children (48.4%) remained within the same cognitive range (full-scale intelligence quotient, FSIQ<70 of Wechsler preschool and primary scale of intelligence), 12 had borderline intellectual functioning (FSIQ, 70-85), 6 improved to average intellectual functioning (FSIQ>85), and 5 had specific language impairment, 9 had autism spectrum disorders. At the initial test, 38 of the 70 children had cognitive developmental quotients (C-DQ) below 70. Of the 38 children in the follow-up assessment, 23 children (60.5%) remained within the same cognitive range (FSIQ<70). The correlation coefficient for MDI and FSIQ was 0.530 (P<0.0001) and that for C-DQ and FSIQ was 0.727 (P<0.0001). There was a strong correlation between C-DQ and FSIQ, and a moderate correlation between MDI and FSIQ. Conclusion: Low MDI scores reflect a specific delay in cognitive abilities, communication skills, or both. The C-DQ, receptive language development quotient, and social maturity quotient also help to distinguish between children with isolated language delay and children with cooccurring cognitive impairment. Moreover, changes in the developmental profile during preschool years are not unusual in children with language delay. Follow-up reassessments prior to the start of school are required for a more accurate diagnosis and intervention.

The Effect of Self-Leadership on the Lntention of Start-up in Women: The Mediation Effect of Self-Efficacy (여성의 셀프리더쉽이 창업의도에 미치는 영향 : 자기효능감의 매개효과)

  • Lim, Jeong Sook;Kim, Sung Sook
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.15 no.5
    • /
    • pp.65-76
    • /
    • 2020
  • This study analyzed the impact of women's self-preservation on their intention to start a business by using self-efficacy as a mediation, reflecting the importance of women's self-preservation to adapt to the new environment of start-up. In particular, in addition to the overall self-preservation, the sub-factors of behavioral delay, compensatory natural strategy, and constructive thinking strategy were also validated. As a research method, 198 people who responded to the online survey were analyzed using Model 4 of the PROCESS macro proposed by Hayes(2018), and indirect effects were analyzed by designating 5,000 bootstrapping samples. The findings were as follows. First, self-efficacy has been shown to have a mediating effect in which women's self-preservation influences their intention to start a business. At this time, the medium effect was shown as a partial medium. Second, the sense of self-efficacy was found to have a mediating effect on women's behavior-oriented strategies affecting their intention to start a business. At this time, the medium effect was shown as a partial medium. Third, self-efficacy was found to have a mediating effect in which women's natural compensatory strategies affect their intention to start a business. At this time, the medium effect was shown as a partial medium. Fourth, self-efficacy was found to have a mediating effect in which women's constructive thinking strategies affect their intention to start a business. At this time, the medium effect was shown as a complete medium. This shows that the higher a woman's self-preservation, the higher her self-efficacy and willingness to start a business. Based on the results of these studies, he made a developed proposal for women's start-ups.

A 500 MHz-to-1.2 GHz Reset Free Delay Locked Loop for Memory Controller with Hysteresis Coarse Lock Detector

  • Chi, Han-Kyu;Hwang, Moon-Sang;Yoo, Byoung-Joo;Choe, Won-Jun;Kim, Tae-Ho;Moon, Yong-Sam;Jeong, Deog-Kyoon
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.11 no.2
    • /
    • pp.73-79
    • /
    • 2011
  • This paper describes a reset-free delay-locked loop (DLL) for a memory controller application, with the aid of a hysteresis coarse lock detector. The coarse lock loop in the proposed DLL adjusts the delay between input and output clock within the pull-in range of the main loop phase detector. In addition, it monitors the main loop's lock status by dividing the input clock and counting its multiphase edges. Moreover, by using hysteresis, it controls the coarse lock range, thus reduces jitter. The proposed DLL neither suffers from harmonic lock and stuck problems nor needs an external reset or start-up signal. In a 0.13-${\mu}m$ CMOS process, post-layout simulation demonstrates that, even with a switching supply noise, the peak-to-peak jitter is less than 30 ps over the operating range of 500-1200 MHz. It occupies 0.04 $mm^2$ and dissipates 16.6 mW at 1.2 GHz.

Fast Booting of Linux Kernel using Dynamic IDE Device Probing Scheme (동적 IDE 장치 검사 기법을 이용한 리눅스 커널의 빠른 부팅)

  • Kim, Young-Ju
    • The Journal of the Korea Contents Association
    • /
    • v.7 no.1
    • /
    • pp.139-146
    • /
    • 2007
  • Most of embedded systems have been developed practically based on the PC platform equipped with Intel x86 CPU since it is able to reduce the total time for product development and improve the reliability of product by making use of a variety of solutions developed for a long time in the PC environment. Also, embedded systems based on PC-platform mainly use a high-capacity hard disk as data storage device for applications intending to store multimedia data. Recently, while the capacity of hard disk is increasing rapidly, the start-up ready time of hard disk is growing longer more than 30 seconds. The lengthened start-up ready time may delay the booting time of embedded system seriously, weighting users down with inconvenience. This paper proposes the refined system architecture and the dynamic IDE device probing method for fast booting of linux kernel in the embedded system based on PC platform with high-capacity hard disks, and the performance of proposed methods is evaluated and presented.