• Title/Summary/Keyword: CH selection

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Optimal Cluster Head Selection Method for Sectorized Wireless Powered Sensor Networks (섹터기반 무선전력 센서 네트워크를 위한 최적 클러스터 헤드 선택 방법)

  • Choi, Hyun-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.1
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    • pp.176-179
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    • 2022
  • In this paper, we consider a sectorized wireless powered sensor network (WPSN), wherein sensor nodes are clustered based on sectors and transmit data to the cluster head (CH) using energy harvested from a hybrid access point. We construct a system model for this sectorized WPSN and find optimal coordinates of CH that maximize the achievable transmission rate of sensing data. To obtain the optimal CH with low overhead, we perform an asymptotic geometric analysis (GA). Simulation results show that the proposed GA-based CH selection method is close to the optimal performance exhibited by exhaustive search with a low feedback overhead.

A Site Selection of Public Facility Based on An Accessibility Theory & GIS Spatial Analysis Technologies (접근성이론과 GIS 공간분석기법을 활용한 행정기관의 입지선정)

  • Kim, Hwang Bae;Kim, Sigon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.3D
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    • pp.385-391
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    • 2006
  • It is very important to make a decision for locating public facility site in a objectively way people in general agree with. This is because public facility affects not only daily life of people in there but also a regional development. This paper sets up a site selection model which utilize an accessibility theory and GIS spatial analysis techniques. This model has been applied to all the twelve alternatives of Chungnam Provincial Office (CPO) sites which are well known to the public. On the criterion of average access time from all the other areas in Chungnam Province, CH alternative is found to be the best one followed by CH/AS, AS alternatives. On the basis of total people-travel time CH/AS alternative turns out to be the best one followed by CH, AS alternatives. In conclusion top three best locations for CPO are CH and AS area where transportation facility are in good condition and population density is highest in Chungnam Province. This fact implies that a transportation accessibility and population density are the primary key in determining the location of public facility.

A New Cluster Head Selection Technique based on Remaining Energy of Each Node for Energy Efficiency in WSN

  • Subedi, Sagun;Lee, Sang-Il;Lee, Jae-Hee
    • International journal of advanced smart convergence
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    • v.9 no.2
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    • pp.185-194
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    • 2020
  • Designing of a hierarchical clustering algorithm is one of the numerous approaches to minimize the energy consumption of the Wireless Sensor Networks (WSNs). In this paper, a homogeneous and randomly deployed sensor nodes is considered. These sensors are energy constrained elements. The nominal selection of the Cluster Head (CH) which falls under the clustering part of the network protocol is studied and compared to Low Energy Adaptive Clustering Hierarchy (LEACH) protocol. CHs in this proposed process is the function of total remaining energy of each node as well as total average energy of the whole arrangement. The algorithm considers initial energy, optimum value of cluster heads to elect the next group of cluster heads for the network as well as residual energy. Total remaining energy of each node is compared to total average energy of the system and if the result is positive, these nodes are eligible to become CH in the very next round. Analysis and numerical simulations quantify the efficiency and Average Energy Ratio (AER) of the proposed system.

Exploring indicators of genetic selection using the sniffer method to reduce methane emissions from Holstein cows

  • Yoshinobu Uemoto;Tomohisa Tomaru;Masahiro Masuda;Kota Uchisawa;Kenji Hashiba;Yuki Nishikawa;Kohei Suzuki;Takatoshi Kojima;Tomoyuki Suzuki;Fuminori Terada
    • Animal Bioscience
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    • v.37 no.2
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    • pp.173-183
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    • 2024
  • Objective: This study aimed to evaluate whether the methane (CH4) to carbon dioxide (CO2) ratio (CH4/CO2) and methane-related traits obtained by the sniffer method can be used as indicators for genetic selection of Holstein cows with lower CH4 emissions. Methods: The sniffer method was used to simultaneously measure the concentrations of CH4 and CO2 during milking in each milking box of the automatic milking system to obtain CH4/CO2. Methane-related traits, which included CH4 emissions, CH4 per energy-corrected milk, methane conversion factor (MCF), and residual CH4, were calculated. First, we investigated the impact of the model with and without body weight (BW) on the lactation stage and parity for predicting methane-related traits using a first on-farm dataset (Farm 1; 400 records for 74 Holstein cows). Second, we estimated the genetic parameters for CH4/CO2 and methane-related traits using a second on-farm dataset (Farm 2; 520 records for 182 Holstein cows). Third, we compared the repeatability and environmental effects on these traits in both farm datasets. Results: The data from Farm 1 revealed that MCF can be reliably evaluated during the lactation stage and parity, even when BW is excluded from the model. Farm 2 data revealed low heritability and moderate repeatability for CH4/CO2 (0.12 and 0.46, respectively) and MCF (0.13 and 0.38, respectively). In addition, the estimated genetic correlation of milk yield with CH4/CO2 was low (0.07) and that with MCF was moderate (-0.53). The on-farm data indicated that CH4/CO2 and MCF could be evaluated consistently during the lactation stage and parity with moderate repeatability on both farms. Conclusion: This study demonstrated the on-farm applicability of the sniffer method for selecting cows with low CH4 emissions.

Distance Aware Intelligent Clustering Protocol for Wireless Sensor Networks

  • Gautam, Navin;Pyun, Jae-Young
    • Journal of Communications and Networks
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    • v.12 no.2
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    • pp.122-129
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    • 2010
  • Energy conservation is one of the most important issues for evaluating the performance of wireless sensor network (WSN) applications. Generally speaking, hierarchical clustering protocols such as LEACH, LEACH-C, EEEAC, and BCDCP are more efficient in energy conservation than flat routing protocols. However, these typical protocols still have drawbacks of unequal and high energy depletion in cluster heads (CHs) due to the different transmission distance from each CH to the base station (BS). In order to minimize the energy consumption and increase the network lifetime, we propose a new hierarchical routing protocol, distance aware intelligent clustering protocol (DAIC), with the key concept of dividing the network into tiers and selecting the high energy CHs at the nearest distance from the BS. We have observed that a considerable amount of energy can be conserved by selecting CHs at the nearest distance from the BS. Also, the number of CHs is computed dynamically to avoid the selection of unnecessarily large number of CHs in the network. Our simulation results showed that the proposed DAIC outperforms LEACH and LEACH-C by 63.28% and 36.27% in energy conservation respectively. The distance aware CH selection method adopted in the proposed DAIC protocol can also be adapted to other hierarchical clustering protocols for the higher energy efficiency.

Association of Cold-heat Pattern and Anthropometry/body Composition in Individuals Between 50-80 Years of Age (한열변증과 체형 및 체성분의 연관성 분석 - 50세 이상 장년 및 노년층을 대상으로)

  • Mun, Sujeong;Park, Kihyun;Lee, Siwoo
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.34 no.4
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    • pp.209-214
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    • 2020
  • The association of cold-heat (CH) pattern and anthropometry/body composition has been suggested in that they are related to thermoregulation. We aimed to study the association of CH pattern and anthropometry/body composition. A total of 1479 individuals aged 50-80 years were included in the study, and their CH pattern were evaluated by a self-administered questionnaire. After adjustment for age and sex, the CH score were significantly correlated with weight, BMI (body mass index), body surface area, waist-hip ratio, fat free mass, body fat mass, body cell mass, intracellular water, extracellular water, and basal metabolic rate; however, the correlation coefficients were mostly low (0.15-0.24). The selected variables for predicting CH score were various according to the methods used for variable selection; however, the adjusted R-squared of the final models were all around 0.12. Thus the most parsimonious model could be the one that includes sex and BMI. In conclusion, various anthropometry and body composition indices were associated with CH pattern. Future studies are necessary to improve the performance of the prediction model.

Isolation and Identification of Burkholderia pyrrocinia CH-67 to Control Tomato Leaf Mold and Damping-off on Crisphead Lettuce and Tomato

  • Lee, Kwang-Youll;Kong, Hyun-Gi;Choi, Ki-Hyuck;Lee, Seon-Woo;Moon, Byung-Ju
    • The Plant Pathology Journal
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    • v.27 no.1
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    • pp.59-67
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    • 2011
  • A bacterial strain CH-67 which exhibits antagonism towards several plant pathogenic fungi such as Botrytis cinerea, Fulvia fulva, Rhizoctonia solani, Sclerotinia sclerotiorum, Colletotrichum sp. and Phytophthora sp. was isolated from forest soil by a chitin-baiting method. This strain was identified as Burkholderia cepacia complex (Bcc) and belonging to genomovar IX (Burkholderia pyrrocinia) by colony morphology, biochemical traits and molecular method like 16S rRNA and recA gene analysis. This strain was used to develop a bio-fungicide for the control of tomato leaf mold caused by Fulvia fulva. Various formulations of B. pyrrocinia CH-67 were prepared using fermentation cultures of the bacterium in rice oil medium. The result of pot experiments led to selection of the wettable powder formulation CH67-C containing modified starch as the best formulation for the control of tomato leaf mold. CH67-C, at 100-fold dilution, showed a control value of 85% against tomato leaf mold. Its disease control efficacy was not significantly different from that of the chemical fungicide triflumidazole. B. pyrrocinia CH-67 was also effective in controlling damping-off caused by Rhizoctonia solani PY-1 in crisphead lettuce and tomato plants. CH67-C formulation was recognized as a cell-free formulation since B. pyrrocinia CH-67 was all lethal during formulation process. This study provides an effective biocontrol formulation of biofungicide using B. pyrrocinia CH-67 to control tomato leaf mold and damping-off crisphead lettuce and tomato.

Explaining the Drift Behavior of Caffeine and Glucosamine After Addition of Ethyl Lactate in the Buffer Gas of an Ion Mobility Spectrometer

  • Fernandez-Maestre, Roberto;Velasco, Andres Reyes;Hill, Herbert H.
    • Bulletin of the Korean Chemical Society
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    • v.35 no.4
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    • pp.1023-1028
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    • 2014
  • Protonated caffeine ($CH^+$) and glucosamine ($GH^+$) overlapped in an analysis with ion mobility spectrometryquadrupole mass spectrometry. Ethyl lactate vapor (L) at different concentrations from 0 to 22 mmol $m^{-3}$ was added as a buffer gas modifier to separate these signals. The drift times of $CH^+$ and $GH^+$ increased with L concentration. The drift time increase was associated to clustering equilibria of $CH^+$ and $GH^+$ with one molecule of L and the equilibrium of $GH^+$ was more displaced to the formation of $GLH^+$ than that of $GLH^+$. $GH^+$ clustered more to L than $CH^+$ because $GLH^+$ formed more stable hydrogen bonds (26.30 kcal/mol) than $GLH^+$ (24.66 kcal/mol) and the positive charge in $GH^+$ was more sterically accessible than in $CH^+$. The aim of this work was to use theoretical calculations to guide the selection of a buffer gas modifier for IMS separations of two compounds that overlap in the mobility spectra and predict this separation, simplifying that empirical process.

Dietary Selection of Fat by Heat-stressed Broiler Chickens

  • Zulkifli, I.;Htin, Nwe Nwe;Alimon, A.R.;Loh, T.C.;Hair-Bejo, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.2
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    • pp.245-251
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    • 2007
  • A total of 160 d-old male broiler chicks (Cobb) were brooded for three weeks and then maintained at $24{\pm}1^{\circ}C$. Commencing from d 21, chicks were assigned to one of four feeding regimens: (1) diet with 8% palm oil (PO), (2) diet with 8% soybean oil (SO), (3) diet without added fat (control), (4) a choice of PO, SO and control (CH). The diets were formulated to maintain a constant ratio of energy and protein. From d 28 to 41, all birds were exposed to $34{\pm}1^{\circ}C$. The PO, SO and CH birds had greater body weight than controls on d 42. The PO but not SO diet reduced mortality rate, body temperature and serum creatine kinase level of broiler chickens during heat exposure. Although the total intake of control, PO and SO diets was not significantly different during heat exposure, the CH birds had lower creatine kinase activity and mortality rate than those provided SO diet but not significantly different from the birds fed control and PO diets. The relative abdominal fat weight and breast intramuscular fat content percentage were significantly lower in the control birds than those of PO, SO and CH groups. There were no significant differences in both parameters among the three latter groups. These findings suggest that the uncertainty of how much dietary fat to put into diets for heat stressed broilers can be overcome by allowing them to select their own consumption.

Semiparametric Seasonal Cointegrating Rank Selection

  • Seong, Byeong-Chan;Ahn, Sung-K.;Ch, Sin-Sup
    • The Korean Journal of Applied Statistics
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    • v.24 no.5
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    • pp.791-797
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    • 2011
  • This paper considers the issue of seasonal cointegrating rank selection by information criteria as the extension of Cheng and Phillips (2009). The method does not require the specification of lag length in vector autoregression, is convenient in empirical work, and is in a semiparametric context because it allows for a general short memory error component in the model with only lags related to error correction terms. Some limit properties of usual information criteria are given for the rank selection and small Monte Carlo simulations are conducted to evaluate the performances of the criteria.