• Title/Summary/Keyword: Critical Node

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A Residual Power Estimation Scheme Using Machine Learning in Wireless Sensor Networks (센서 네트워크에서 기계학습을 사용한 잔류 전력 추정 방안)

  • Bae, Shi-Kyu
    • Journal of Korea Multimedia Society
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    • v.24 no.1
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    • pp.67-74
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    • 2021
  • As IoT(Internet Of Things) devices like a smart sensor have constrained power sources, a power strategy is critical in WSN(Wireless Sensor Networks). Therefore, it is necessary to figure out the residual power of each sensor node for managing power strategies in WSN, which, however, requires additional data transmission, leading to more power consumption. In this paper, a residual power estimation method was proposed, which uses ignorantly small amount of power consumption in the resource-constrained wireless networks including WSN. A residual power prediction is possible with the least data transmission by using Machine Learning method with some training data in this proposal. The performance of the proposed scheme was evaluated by machine learning method, simulation, and analysis.

DIFFUSIVE AND STOCHASTIC ANALYSIS OF LOKTA-VOLTERRA MODEL WITH BIFURCATION

  • C.V. PAVAN KUMAR;G. RANJITH KUMAR;KALYAN DAS;K. SHIVA REDDY;MD. HAIDER ALI BISWAS
    • Journal of applied mathematics & informatics
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    • v.41 no.1
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    • pp.11-31
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    • 2023
  • The paper presents a critical analysis of selected topics related to the modeling of interacting species in which prey has nonlinear reproduction, which is in competition with predator. The mathematical model's stochastic stability is investigated. The method of designing appropriate Lyapunov functions is used to identify permanence conditions among the parameters of the model and conditions for the structure to no longer be extinct. The system's two-dimensional diffusive stability is regarded and studied. The system experiences the process of saddle-node bifurcation by varying the death rate of predator parameter. Further effects of parameters that undergo inherent oscillations are numerically investigated, revealing that as the intensity of predation parameter b is increased, the device encounters non-periodic and damped oscillations.

Critical Elastic Buckling Load Investigation of Aluminium Alloy A6082-T6 Square plate Subjected to Patch Loading (패치 로딩을 받는 알루미늄 합금 A6082-T6 사각형 판의 임계 탄성좌굴하중 검토)

  • Oh, Young-Cheol;Ko, Jae-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.4
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    • pp.451-460
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    • 2014
  • In this paper, we examined the problem of the structural stability according to the patch load of a rectangular plate that reflects the material properties of A6082-T6 is used primarily for marine plant structure. it applied to the four patch loading shapes, the effect of aspect ratio, a boundary condition and calculated the critical elastic buckling load. Calculating the critical elastic buckling load, During the eigenvalue buckling analysis it is applied to the shell181 as 4 node shell element. when the plate subjected to patch loading compare to the plate under a uniform axial compression load, it is possible observed to occur the different elastic buckling behaviour and it could be confirmed that it is affected significantly on a variable position and type of loadings, such as the effect of the aspect ratio. Also, Critical elastic buckling load according to th patch loading type in simply supported rectangular plate a/b=1.0, ${\gamma}b$=200mm are calculated 67%(Loading type I), 119 %(Loading type II), 76 %(Loading type III), 160 %(Loading type IV), respectively. Loading type I and III could be determined with the strong elastic buckling behavior much more than Loading type II and IV.

A Critical Path Search and The Project Activities Scheduling (임계경로 탐색과 프로젝트 활동 일정 수립)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.141-150
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    • 2012
  • This paper suggests a critical path search algorithm that can easily draw PERT/GANTT chart which manages and plans a project schedule. In order to evaluate a critical path that determines the project schedule, Critical Path Method (CPM) is generally utilized. However, CPM undergoes 5 stages to calculate the critical path for a network diagram that is previously designed according to correlative relationship and execution period of project execution activities. And it may not correctly evaluate $T_E$ (The Earliest Time), since it does not suggest the way how to determine the sequence of the nodes activities that calculate the $T_E$. Also, the sequence of the network diagram activities obtained from CPM cannot be visually represented, and hence Lucko suggested an algorithm which undergoes 9 stages. On the other hand, the suggested algorithm, first of all, decides the sequence in advance, by reallocating the nodes into levels after Breadth-First Search of the network diagram that is previously designed. Next, it randomly chooses nodes of each level and immediately determines the critical path only after calculation of $T_E$. Finally, it enables the representation of the execution sequence of the project activity to be seen precisely visual by means of a small movement of $T_E$ of the nodes that are not belonging to the critical path, on basis of the $T_E$ of the nodes which belong to the critical path. The suggested algorithm has been proved its applicability to 10 real project data. It is able to get the critical path from all the projects, and precisely and visually represented the execution sequence of the activities. Also, this has advantages of, firstly, reducing 5 stages of CPM into 1, simplifying Lucko's 9 stages into 2 stages that are used to clearly express the execution sequence of the activities, and directly converting the representation into PERT/GANTT chart.

Triple Negative Breast Cancer in People of North East India: Critical Insights Gained at a Regional Cancer Centre

  • Sharma, Mousumi;Sharma, Jagannath Dev;Sarma, Anupam;Ahmed, Shiraj;Kataki, Amal Chandra;Saxena, Rahul;Sharma, Dilutpal
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.11
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    • pp.4507-4511
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    • 2014
  • Background: Breast cancer is a heterogeneous disease comprising of distinct biological subtypes with many targeted prognostic biomarkers having therapeutic implications. However, no specific targeted therapy for triple negative breast cancer has been discovered to date and hence further research is needed. Aim: The aim and objectives of the present study were to examine the prevalence of triple negative breast cancer (TNBC) in North-East India and to compare the clinicopathological parameters in two study groups defined by immunohistochemistry (IHC) - "TNBC" and "Others". Materials and Methods: We carried out a retrospective study in a cohort of 972 patients diagnosed with invasive breast carcinoma in the Department of Pathology, Dr. B. Borooah Cancer Institute, a Regional Cancer Centre for treatment and research, Guwahati, for a period of 3 years and 10 months from January 2010 to October 2013. Based on IHC findings, patients were divided into two groups - "TNBC" and "Others". All relevant clinicopathological parameters were compared in both. TNBC were defined as those that were estrogen receptor (ER), progesterone receptor (PR), and HER2/neu negative while those positive for any of these markers were defined as "Others". Results: In this study, out of total 972 cases 31.9% (310 cases) were defined as TNBC and 662 cases (68.1%) as "Others" based on IHC markers. Compared to the "Others" category, TNBC presented at an early age (mean 40 years), were associated with high grade large tumours and high rate of node positivity, IDC NOS being the most common histological subtype in TNBC. Conclusions: TNBC accounts for a significant portion of breast cancers in this part of India and commonly present at younger age and tend to be large high grade tumours.

Energy-efficient Routing in MIMO-based Mobile Ad hoc Networks with Multiplexing and Diversity Gains

  • Shen, Hu;Lv, Shaohe;Wang, Xiaodong;Zhou, Xingming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.2
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    • pp.700-713
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    • 2015
  • It is critical to design energy-efficient routing protocols for battery-limited mobile ad hoc networks, especially in which the energy-consuming MIMO techniques are employed. However, there are several challenges in such a design: first, it is difficult to characterize the energy consumption of a MIMO-based link; second, without a careful design, the broadcasted RREP packets, which are used in most energy-efficient routing protocols, could flood over the networks, and the destination node cannot decide when to reply the communication request; third, due to node mobility and persistent channel degradation, the selected route paths would break down frequently and hence the protocol overhead is increased further. To address these issues, in this paper, a novel Greedy Energy-Efficient Routing (GEER) protocol is proposed: (a) a generalized energy consumption model for the MIMO-based link, considering the trade-off between multiplexing and diversity gains, is derived to minimize link energy consumption and obtain the optimal transmit model; (b) a simple greedy route discovery algorithm and a novel adaptive reply strategy are adopted to speed up path setup with a reduced establishment overhead; (c) a lightweight route maintenance mechanism is introduced to adaptively rebuild the broken links. Extensive simulation results show that, in comparison with the conventional solutions, the proposed GEER protocol can significantly reduce the energy consumption by up to 68.74%.

Energy Efficient Routing Protocol in Wireless Sensor Network (무선 센서 네트워크에서 에너지 효율적인 라우팅 프로토콜)

  • 손병락;김중규
    • Journal of Korea Society of Industrial Information Systems
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    • v.9 no.2
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    • pp.65-73
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    • 2004
  • By the progress of communication and hardware technology, It is possible to organize wireless sensor nodes using the tiny sensor in recently. It is a critical aspect to minimize energy consumption for long-term lively sensor because wireless sensor nodes are associated with the available resources. The wireless sensor network is restricted in communication, exhaustion of power, and computation but it is very similar an Ad-Hoc network. Each sensor node products a few data and application layer of each sensor has slow transmitting feature. Unlike Ad-hoc, which is usually source or sink, base station of the each senor nodes works as sink and the other nodes except sink node works as source. Generally, wireless sensor network keep staying fixed state and observing circumstances continuously after setting up. It doesnt fit for the wireless sensor networks under functioning of existing ad-hoc networks because original Ad-Hoc network routing protocol couldnt operate for wireless sensor network features. This thesis propose the effective routing protocol way in the filed of the expanded routing protocol based on tree with considering on the characteristic of wireless sensor networks pattern.

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Somatic Embryogenesis and Plant Regeneration from Immature Zygotic Embryo Culture in Pepper (Capsicum annuum L.)

  • Jo, Jeong-Yon;Choi, Eun-Young;Choi, Dong-Su;Lee, Kwang-Woong
    • Journal of Plant Biology
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    • v.39 no.2
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    • pp.127-135
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    • 1996
  • An efficient system of somatic embryogenesis was established for the red pepper plant (Capsicum annuum L. cv. Nokkwang) usign immature zygotic embryos. The size of the immature zygotic embryos and the concentrations of 2, 4-D and sucrose were found to be critical. Somatic embryos were induced via callus or directly from explants and regenerated into plantlets successfully. When zygotic embryos 1~2 mm long were cultured on the modified Murashige-Skoong (MS) medium supplemented with 2 mg/L 2, 4-D for 3 weeks in the dark, somatic embryos were induced directly from the apical region of zygotic embryos with the highest frequency being approximately 90%. To mature the somatic embryos, ABA and an ethylene inhibitor AgNO3 were used. The highest frequency of shoot regeneration (25% in each) resulted at 2$\mu$M ABA or 20$\mu$M AgNO3 treatment at rates 3.7 and 1.6 times control, respectively. Shoots developed mainly from the cotyledonary node on CoCl2-containing medium, and from the upper side of cotyledon on medium containing AgNO3 while the embryos on the control medium produced shoots from both the cotyledonary node and the upper region of cotyledons both at frequencies of 50%. Indirect somatic embryogenesis via callus was induced at an efficiency of approximately 10% with zygotic embryos 3~4 mm long cultured on MS medium containing 5~10 mg/L, 2, 4-D for 5~7 weeks under a continuous light condition. The plants regenerated from the somatic embryos were morphologically normal. Using scanning electron microscopy, the direct and indirect somatic embryogeneses were observed to follow the globular, heart and torpedo stages, similar to zygotic embryogenesis. Also, suspensors appeared in the early globular and ovoid-shaped late globular embryos during indirect somatic embryogenesis.

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An Energy Efficient Cluster Formation Algorithm for Wireless Sensor Networks (무선 센서 네트워크를 위한 에너지 효율적인 클러스터 구성 알고리즘)

  • Han, Uk-Pyo;Lee, Hee-Choon;Chung, Young-Jun
    • The KIPS Transactions:PartC
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    • v.14C no.2
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    • pp.185-190
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    • 2007
  • The efficient node energy utilization is one of important performance factors in wireless sensor networks because sensor nodes operate with limited battery power. To extend the lifetime of the wireless sensor networks, maintaining balanced power consumption between sensor nodes is more important than reducing each energy consumption of the sensor node in the network. In this paper, we proposed a cluster formation algorithm to extend the lifetime of the networks and to maintain a balanced energy consumption of nodes. To obtain it, we add a tiny slot in a round frame, which enables to exchange the residual energy messages between the base station (BS). cluster heads, and nodes. The performance of the proposed protocol has been examined and evaluated with the NS 2 simulator. As a result of simulation, we have confirmed that our proposed algorithm show the better performance in terms of lifetime than LEACH. Consequently, our proposed protocol can effectively extend the network lifetime without other critical overhead and performance degradation.

Collaborative Stepwise Movement of Mobile Sensor Nodes for Energy Efficient Dynamic Sensor Network Coverage Maintenance (모바일 센서노드들의 협동형 단계적 이동기법 기반의 에너지 효율적인 동적 센서네트워크 커버리지 관리)

  • Han, Ngoc-Soc;Kim, Seong-Whan
    • The KIPS Transactions:PartC
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    • v.16C no.4
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    • pp.535-542
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    • 2009
  • Wireless Sensor Network (WSN) is a wireless network consisting of spatially distributed autonomous devices, using sensors to cooperatively monitor physical or environmental conditions. WSNs face the critical challenge of sustaining long-term operation on limited battery energy. Coverage maintenance has been proposed as a promising approach to prolong network lifetime. Mobile sensors equipped with communication devices can be leveraged to overcome the coverage problem. In this paper, we propose a stepwise movement scheme using perimeter coverage property for the coverage maintenance problem. In our scheme, each sensor monitors neighboring dead nodes, determines vulnerable node (i.e. dead node which makes uncovered area), computes the center of uncovered area HC, and makes a coordinated stepwise movement to compensate the uncovered area. In our experimental results, our scheme shows at least 50 % decrease in the total moving distance which determines the energy efficiency of mobile sensor.