• Title/Summary/Keyword: Time-Delay Control

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Combined Foliar Spray of Boron, Calcium, and Silicon can Influence Quality and Shelf Life of Cherry Tomato in Modified Atmosphere Packaging (붕소, 칼슘, 규소의 복합 엽면시비가 방울토마토의 품질과 MAP 조건에서 저장성에 미치는 영향)

  • Islam, Mohammad Zahirul;Mele, Mahmuda Akter;Han, Su Jeong;Kim, Ju Young;Choi, In-Lee;Yoon, Jae Su;Yoon, Hyuk Sung;Park, Jong-Man;Kim, Il-Seop;Choi, Ki-Young;Kang, Ho- Min
    • Journal of Bio-Environment Control
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    • v.26 no.4
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    • pp.310-316
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    • 2017
  • This study was analyzed the effects of boron (B), calcium (Ca), silicon (Si) on quality and shelf life of 'Unicorn' cherry tomato at the light red maturity-stage. The storage conditions were modified atmosphere packaging (MAP) by oxygen transmission rate (OTR) packaging film at $5^{\circ}C$, $11^{\circ}C$, and $24^{\circ}C$. Respiration and ethylene production were the lowest in B + Ca + Si -treated tomato fruits. The lowest fresh weight loss and the longest shelf life resulted from the B + Ca + Si treatment. And the firmness was enhanced by B + Ca + Si treatment at harvest time, and it was retained after storage at $5^{\circ}C$, $11^{\circ}C$, and $24^{\circ}C$. Significantly lower soluble solids, lycopene, and color development were found at B + Ca + Si-treated tomato fruits compared with control after storage. Moreover, the highest titratable acidity and vitamin C content were observed in B + Ca + Si-treated tomato fruits after storage. From the above results, it was concluded that B + Ca + Si combined treatment can delay the maturity of cherry tomato after harvesting, and retained the firmness and prolong the shelf life.

A Study on Designing Method of VoIP QoS Management Framework Model under NGN Infrastructure Environment (NGN 기반환경 에서의 VoIP QoS 관리체계 모델 설계)

  • Noh, Si-Choon;Bang, Kee-Chun
    • Journal of Digital Contents Society
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    • v.12 no.1
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    • pp.85-94
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    • 2011
  • QoS(Quality of Service) is defined as "The collective effect of service performance which determines the degree of satisfaction of a user of the service" by ITU-T Rec. E.800. While the use of VoIP(Voice Over Internet Protocol) has been widely implemented, persistent problems with QoS are a very important sue which needs to be solved. This research is finding the assignment of VoIP QoS to deduct how to manage the control system and presenting the QoS control process and framework under NGN(Next Generation Network) environment. The trial framework is the modeling of the QoS measurement metrics, instrument, equipment, method of measurement, the series of cycle & the methodology about analysis of the result of measurement. This research underlines that the vulnerability of the VoIP protocol in relation to its QoS can be guaranteed when the product quality and management are controlled and measured systematically. Especially it's very important time to maintain the research about VoIP QoS measurement and control because the big conversion of new network technology paradigm is now spreading. In addition, when the proposed method is applied, it can reduce an overall delay and can contribute to improved service quality, in relation to signal, voice processing, filtering more effectively.

Speed Control of Marine Gas Turbine Engine using Nonlinear PID Controller (비선형 PID 제어기를 이용한 선박용 가스터빈 엔진의 속도 제어)

  • Lee, Yun-Hyung;So, Myung-Ok
    • Journal of Navigation and Port Research
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    • v.39 no.6
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    • pp.457-463
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    • 2015
  • A gas turbine engine plays an important role as a prime mover that is used in the marine transportation field as well as the space/aviation and power plant fields. However, it has a complicated structure and there is a time delay element in the combustion process. Therefore, an elaborate mathematical model needs to be developed to control a gas turbine engine. In this study, a modeling technique for a gas generator, a PLA actuator, and a metering valve, which are major components of a gas turbine engine, is explained. In addition, sub-models are obtained at several operating points in a steady state based on the trial running data of a gas turbine engine, and a method for controlling the engine speed is proposed by designing an NPID controller for each sub-model. The proposed NPID controller uses three kinds of gains that are implemented with a nonlinear function. The parameters of the NPID controller are tuned using real-coded genetic algorithms in terms of minimizing the objective function. The validity of the proposed method is examined by applying to a gas turbine engine and by conducting a simulation.

An Early Spectrum Sensing for Efficient Radio Access in Cloud-Conceptual Base Station Systems (클라우드 기지국 시스템에서 효율적 무선 접속을 위한 이른 스펙트럼 감지 기법)

  • Jo, Gahee;Lee, Jae Won;Na, Jee-Hyeon;Cho, Ho-Shin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.1
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    • pp.68-78
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    • 2013
  • In this paper, we propose an early spectrum sensing(ESS) as an advance preparation for radio-access trial, which enables multi-mode terminals to access the most appropriate radio-access system in a cloud-conceptual base station system where multiple radio access technologies(RATs) coexist. Prior to a random access to one of RATs, a multi-mode terminal conducts a spectrum sensing over entire frequency bands of whole RATs, then select the RAT with the lowest sensing power, that is likely to have the most available spectrum. Thus, an access failure caused by that the selected RAT has no available radio spectrum could be avoidable in advance. In computer simulation, we consider as various RATs as possible. First, circuit and packet systems are taken into consideration. In addition, the packet systems are classified according to the feasibility of carrier aggregation(CA). In case of terminal, three modes are considered with circuit-only, packet-only, and multi-mode. Subsequently, packet traffic is classified into real-time and non-real-time traffic with three different tolerable delay levels. The simulation includes a call process starting with a call generation and ending up with a resource allocation reflecting individual user's QoS requirements and evaluates the proposed scheme in terms of the successful access probability, system access time, system balancing factor and packet loss probability.

Design of a Low Power Reconfigurable DSP with Fine-Grained Clock Gating (정교한 클럭 게이팅을 이용한 저전력 재구성 가능한 DSP 설계)

  • Jung, Chan-Min;Lee, Young-Geun;Chung, Ki-Seok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.2
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    • pp.82-92
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    • 2008
  • Recently, many digital signal processing(DSP) applications such as H.264, CDMA and MP3 are predominant tasks for modern high-performance portable devices. These applications are generally computation-intensive, and therefore, require quite complicated accelerator units to improve performance. Designing such specialized, yet fixed DSP accelerators takes lots of effort. Therefore, DSPs with multiple accelerators often have a very poor time-to-market and an unacceptable area overhead. To avoid such long time-to-market and high-area overhead, dynamically reconfigurable DSP architectures have attracted a lot of attention lately. Dynamically reconfigurable DSPs typically employ a multi-functional DSP accelerator which executes similar, yet different multiple kinds of computations for DSP applications. With this type of dynamically reconfigurable DSP accelerators, the time to market reduces significantly. However, integrating multiple functionalities into a single IP often results in excessive control and area overhead. Therefore, delay and power consumption often turn out to be quite excessive. In this thesis, to reduce power consumption of dynamically reconfigurable IPs, we propose a novel fine-grained clock gating scheme, and to reduce size of dynamically reconfigurable IPs, we propose a compact multiplier-less multiplication unit where shifters and adders carry out constant multiplications.

Boosting up the Mount Latency of NAND Flash File System using Byte-addressable NVRAM (바이트 접근성을 가지는 비휘발성 메모리 소자를 이용한 낸드 플래시 파일 시스템의 부팅시간 개선 기법)

  • Jeon, Byeong-Gil;Kim, Eun-Ki;Shin, Hyung-Jong;Han, Seok-Hee;Won, Yoo-Jip
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.3
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    • pp.256-260
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    • 2008
  • This paper describes an improvement of mount-time delay in NAND Flash file systems. To improve file system mount performance, this work configures a hierarchical storage system with byte-addressable NVRAM and NAND Flash memory, and let the meta data of a file system allocated in the NVRAM. Since the meta data are stored in NVRAM supporting data integrity some of the items, which are stored in Spare area and Object Header area of NAND Flash memory to control meta data of NAND Flash file system, could be eliminated. And also, this work eliminates the scanning operation of the Object Header area of previous work FRASH1.0. The scanning operation is definitely required to find out the empty Object Header address for storing the Object Header data and provokes a certain amount of performance loss in file generation and deletion. In this work, an implemented file system, so-called FRASH1.5, is demonstrated, featuring new data structures and new algorithms. The mount time of FRASH1.5 becomes twice as fast as that of the FRASH1.0. The performance in file generation gets improved by about $3{\sim}8%$. In particular, for most large-size files, the FRASH1.5 has 8 times faster mount time than YAFFS, without any performance loss as seen in the file generation.

Recent Development in Rice Seedling Raising in Japan, with Special Reference to the "Nursling Seedlings"

  • Kiyochika, Hoshikawa
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.37 no.2
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    • pp.198-208
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    • 1992
  • Recently, a nursery mat made from rock wool has realized transplanting of the younger seedlings with the ordinary transplanting machines for Chibyo and Chubyo(3 and 4~5 leaved seedling, respectively). The seedlings defined as the 'Nyubyo' or 'Nursling seedlings' became possible to achieve economic profits from the reduction in both working time and costs. It being widely noticed as a strategy to solve the difficulties in current rice cultivation. The nursling seedlings are 1.4 to 2.5 leaves and height at 4.5 to 7cm, grown 4 to 7 days after seeding. They maintain still up to 50 to 80% of their nutrients in the endosperm, and can grow by using only their own nutrients for a certain period of time after transplanting. Nursling seedlings take 2 days in the nursery chamber at 32$^{\circ}C$ after seeding, and 2 days in the greening house at $25^{\circ}C$. This is only 4 days, all together, to make the nursling seedlings of 1.5 leaves which are ready for transplanting. Watering is only needed once at the sowing time. It only takes 1 or 2 waterings even to raise a seedlings for a period of 7 days. The number of nursery boxes can be reduced because it is possible to sow more densely(220 to 240g per box), thus it only needs seedlings of 15 to 16 boxes per 10 a which leads to a reduction in facilities and space needed. Temperature during the nursery period can be artificially adjusted more precisely which may lead to the prevention of temperature stress. The nursling seedlings can root rapid by because the crown roots from the coleoptile node begin to emerge immediately after transplanting. They show strong resistance to low temperature (12$^{\circ}C$) and deep-planting. There is no danger in the rooting of the seedlings even if half of their height is buried into the soil. Moreover, it can root at a rate of up to 65 to 80% even if the full height of the seedlings is buried. They show also strong resistance to submergence (10~15cm). The nursling seedlings tend to grow by producing tillers from lower nodes. It is therefore, necessary to control to keep the proper numbers of tillers per unit area. They have no fear in the delay of heading and their yield components can be so well balanced that the same level of yield was achieved with the nursling seedlings compared to that with Chibyo. It was further suggested that if the surplus tillers can be avoided by such cultivation practices, the number of grain per panicle can be kept greater and higher yield can be realized. Practical experiments with the nursling seedlings conducted in 1989 and 1990 by farmers in various areas showed exciting results. The nursling seedlings will become widely spread, or at least occupy an important position in Japanese and also in Korean rice cultivation techniques.tivation techniques.

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Prediction of Power Consumption for Improving QoS in an Energy Saving Server Cluster Environment (에너지 절감형 서버 클러스터 환경에서 QoS 향상을 위한 소비 전력 예측)

  • Cho, Sungchoul;Kang, Sanha;Moon, Hungsik;Kwak, Hukeun;Chung, Kyusik
    • KIPS Transactions on Computer and Communication Systems
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    • v.4 no.2
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    • pp.47-56
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    • 2015
  • In an energy saving server cluster environment, the power modes of servers are controlled according to load situation, that is, by making ON only minimum number of servers needed to handle current load while making the other servers OFF. This algorithm works well under normal circumstances, but does not guarantee QoS under abnormal circumstances such as sharply rising or falling loads. This is because the number of ON servers cannot be increased immediately due to the time delay for servers to turn ON from OFF. In this paper, we propose a new prediction algorithm of the power consumption for improving QoS under not only normal but also abnormal circumstances. The proposed prediction algorithm consists of two parts: prediction based on the conventional time series analysis and prediction adjustment based on trend analysis. We performed experiments using 15 PCs and compared performance for 4 types of conventional time series based prediction methods and their modified methods with our prediction algorithm. Experimental results show that Exponential Smoothing with Trend Adjusted (ESTA) and its modified ESTA (MESTA) proposed in this paper are outperforming among 4 types of prediction methods in terms of normalized QoS and number of good reponses per power consumed, and QoS of MESTA proposed in this paper is 7.5% and 3.3% better than that of conventional ESTA for artificial load pattern and real load pattern, respectively.

Design of an Efficient Control System for Harbor Terminal based on the Commercial Network (상용망 기반의 항만터미널 효율적인 관제시스템 설계)

  • Kim, Yong-Ho;Ju, YoungKwan;Mun, Hyung-Jin
    • Journal of Industrial Convergence
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    • v.16 no.1
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    • pp.21-26
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    • 2018
  • The Seaborne Trade Volume accounts for 97% of the total. This means that the port operation management system can improve port efficiency, reducing operating costs, and the manager who manages all operations at the port needs to check and respond quickly when delays of work and equipment support is needed. Based on the real-time location information confirmation of yard automation equipment used the existing system GPS, the real-time location information confirmation system is a GPS system of the tablet, rather than a port operation system that monitors location information for the entered information, depending on the completion of the task or the start of the task. Network configurations also reduce container processing delays by using commercial LTE services that do not have shading due to containers in the yard also reduce container processing delays. Trough introduction of smart devices using Android or IOS and container processing scheduling utilizing artificial intelligence, we will build a minimum delay system with Smart Device usage of container processing applications and optimization of container processing schedule. The adoption of smart devices and the minimization of container processing delays utilizing artificial intelligence are expected to improve the quality of port services by confirming the processing containers in real time to consumers who are container information demanders.

Setting and Micro-structures of the Cement Pastes Using Sugar-Based Super Retarding Agents (당류계 초지연성 혼화제를 사용한 시멘트 페이스트의 응결 및 미시구조 특성)

  • Jeong, Yeong-Jin;Hyun, Seung-Yong;Han, Jun-Hui;Kim, Jong;Han, Min-Cheol
    • Journal of the Korea Institute of Building Construction
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    • v.23 no.6
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    • pp.703-714
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    • 2023
  • This research conducts a series of tests to investigate the setting retarding properties and strength development in cement pastes incorporating various types and dosages of sugar-based super retarding agents. Six such agents, including Sucrose, Sugar powder, Saccharin, Aspartame, Stevioside, and Mogroside, commercially available, were selected for evaluation. The study also examines the micro-structural properties of these cement pastes. The test mixtures were prepared using a 27.5% water-to-cement ratio and ordinary Portland cement. Micro-structural analyses were conducted using Scanning Electron Microscopy(SEM), X-Ray Diffraction(XRD), and Energy Dispersive Spectroscopy(EDS). The findings reveal that the incorporation of sucrose, sugar powder, and stevioside significantly retards the setting time. Particularly, adding 0.1% sucrose extended the setting time by approximately two-fold compared to the control(Plain) mixture. Most mixtures, barring those with sugar powder and stevioside, exhibited compressive strength comparable to the Plain mixture. Notably, with 0.2% sucrose, strength measurements were not feasible at 1 day, but at 3 days, the strength gains aligned with the Plain mixture. XRD, SEM, and EDS analyses confirmed the hydration delay(set retarding) of C3S due to sucrose, with further quantitative corroboration provided by EDS. SEM was used to verify the presence or absence of hydration products. The study concludes that sucrose, as a sugar-based retarder, offers effective set retarding capabilities and compressive strength development in concrete.