• Title/Summary/Keyword: Information Loss

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Improvement of Low Pass Filler Using New PBG Structure (새로운 PBG 구조를 이용한 저역통과 여파기 성능 개선에 관한 연구)

  • 이승재;서철헌
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.7A
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    • pp.852-857
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    • 2004
  • In this research, we suggested a new PBG cell with wide stopband. In order to improve the characteristics of the insertion loss, return loss, and ripple, we used two overlapped cells. One is small cell which is made in inside and the other is large cell which is made in outside. The inner cell stops the high band and the outer cell stops the low band. As a result, the new PBG cell had a wide stop band. Insertion loss was about 40dB in stopband and the ripple, and the return loss was improved. Also, the passband is broaden by employing new PBG cells.

Performance Analysis of an Multiplexer for Guaranteed QoS in ATM Networks (ATM망에서 보장된 QoS을 위한 다중화기의 성능분석)

  • 음호식;이명호
    • Journal of the Korea Society of Computer and Information
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    • v.5 no.4
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    • pp.82-89
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    • 2000
  • This study analyzes the cell loss probability of an ATM multiplexer with real time and non-real time bursty traffics. It is assumed that an ATM multiplexer with loss priority control for the analysis. The loss priority control uses the CLP Reld of cell header. For easy analysis and less computation. the multiplexed traffic of the ATM multiplexer was modeled by the MMDP. The ATM multiplexer is simulated by the MMDP/MMDP/l/K queueing system. From the above results, The connection admission of an ATM multiplexer with loss priority control is determined by the cell loss probability with low priority as well as the size of threshold buffer. Therefore, to increase the statistical multiplexing gain it will be good to utilize the loss priority control in order.

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A Study on Soil loss in Forest fire area (산불발생지역에서의 토양유실량에 관한 연구)

  • Yang, In-Tae;Park, Jae-Hoon;Chun, Ki-Sun
    • Journal of Korean Society for Geospatial Information Science
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    • v.11 no.2 s.25
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    • pp.11-16
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    • 2003
  • Soil loss by the rains has effect on natural environment. But It is difficult to find out the data that is surveyed in watershed. In this paper, we choose USLE erosion model, which could be connected easily with GSIS and available generally, and extracted factors which is entered model by using GSIS spatial analysis method. Especially, As revised USLE model, It should be applied in watershed and as it calculated soil loss before Idlest fire and behind, it analysed the degree that it have an effect on soil loss. As each analyzed factors and the result of soil loss estimate consist of 22m-pixel size, we could identify soil loss by each pixel and distribution pattern.

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Analysis of the Percentage Articulation and Voice Packet Loss over the Internet (인터넷상의 음성 패킷손실과 명료도 분석)

  • 고대식;박준석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.8
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    • pp.2090-2095
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    • 1998
  • In this paper, we measured voice packet loss over the Korean Internet and analyzed percentage articulation by variation of the packet loss. To do this, we reviewed real-time transmission service based on RTP/UDP/IP and test method of the transmission quality. and implemented the real-time speech transmission system using GSM and UDP/IP. Monosyllable list has been chosen for the percentage articulation test, each voice packet has been coded and compressed by GSM and it has sequence number to measured packet loss and to recover out-of-order packets. In transmission results using seven router over the Korean Internet, we have show that loss rates reached 1.6% (unload), 22.5%(load) and loss rates after packet recovery by resequencing and FEC are from 9% to 35%. Finally, we have shown that percentage articulations by variation of the network traffic are Table 4.

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An Analysis of Cell Loss Process in an ATM Network Under Partial Buffer Sharing Policy (ATM 전송망에서의 PBS를 이용한 셀 우선 순위 제어 방식의 연구)

  • 곽민곤;성수란;김종권
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.12
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    • pp.2328-2339
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    • 1994
  • The PBS(Partial Buffer Sharing) space priority mechanism is one of priority control methods which may improve the performance of a single server queueing system when mixed traffic with different performance requirements is applied to the system. This paper analyzes the cell loss behavior of PBS assuming loss sensitive traffic and delay sensitive traffic are applied to the system. To derive the successive cell loss probabilities. which are an important performance measure of realtime traffic, we develop a recursive algorithm. Performance results show the successive cell loss probabilities obtained by our method are lager than the probabilities derived from an independent cell loss assumption. These results may indicate the limitation of PBS for realtime traffic and the increase of the admissible load with the criterion of quality of service.

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Review on Predictors of Weight Loss in Moderate to Severe Obesity Treatment (중고도 비만 치료에 있어서 체중감량에 영향을 주는 인자들에 대한 고찰)

  • Sohyun Park;Min-jeong Park;Eunjoo Kim;Young-Woo Lim
    • Journal of Korean Medicine for Obesity Research
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    • v.23 no.2
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    • pp.98-111
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    • 2023
  • Objectives: The purpose of this study was to review predictive factors associated with weight loss in moderate to severe obesity treatment. The direction of the treatment for moderate to severe obesity will be suggested in consideration of various factors. Methods: Authors searched the articles published from 2018 to 2023 in three international databases (PubMed, Embase and the Cochrane Central Register of Controlled Trials) and two domestic databases (Research Information Sharing Service, Korean studies Information Service System). Studies including treatment with moderate to severe obese patients were selected. Results: A total of 43 studies were included. The main factors of weight loss were unchangeable predictors such as low initial degree of obesity, younger age, non-diabetes and high resting energy expenditure with changeable predictors such as increase in protein, physical activity, self-efficacy, initial weight loss and attendance of the treatment. Conclusions: Our review results suggest that based on the characteristics of moderate to severe obese patients, predictors of weight loss can be used to determine treatment and prognosis in various aspects.

3D Cross-Modal Retrieval Using Noisy Center Loss and SimSiam for Small Batch Training

  • Yeon-Seung Choo;Boeun Kim;Hyun-Sik Kim;Yong-Suk Park
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.3
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    • pp.670-684
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    • 2024
  • 3D Cross-Modal Retrieval (3DCMR) is a task that retrieves 3D objects regardless of modalities, such as images, meshes, and point clouds. One of the most prominent methods used for 3DCMR is the Cross-Modal Center Loss Function (CLF) which applies the conventional center loss strategy for 3D cross-modal search and retrieval. Since CLF is based on center loss, the center features in CLF are also susceptible to subtle changes in hyperparameters and external inferences. For instance, performance degradation is observed when the batch size is too small. Furthermore, the Mean Squared Error (MSE) used in CLF is unable to adapt to changes in batch size and is vulnerable to data variations that occur during actual inference due to the use of simple Euclidean distance between multi-modal features. To address the problems that arise from small batch training, we propose a Noisy Center Loss (NCL) method to estimate the optimal center features. In addition, we apply the simple Siamese representation learning method (SimSiam) during optimal center feature estimation to compare projected features, making the proposed method robust to changes in batch size and variations in data. As a result, the proposed approach demonstrates improved performance in ModelNet40 dataset compared to the conventional methods.

Analysis of Korea Soil Loss and Hazard Zone (한국토양유실량 및 토양유실위험 지역 분석)

  • Kim, Joo-Hun;Kim, Kyung-Tak;Lee, Hyo-Jeong
    • Spatial Information Research
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    • v.17 no.3
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    • pp.261-268
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    • 2009
  • This study accomplished to draw a soil erosion map and a grade map of soil loss hazard in Korea. RUSLE and Rainfall-runoff (R) factor, which was estimated by using the rainfall data observed in 59 meteorological stations from 1977 to 2006 (for 30 years). FARD was used to analyze the frequency, and the whole country R factor was estimated according to the frequency. In the analysis of estimating the whole country R factor, Nakdong river has the smallest vaule, but Han river has the biggest value. According to the result of analyzing soil loss, soil loss occurred in a grass land, a bare land and a field in size order, and also approximately 17.2 ton/ha soil loss happened on the whole area. The average soil loss amount by the unit area takes place in a bare land and a grass land a lot. The total amount of soil loss in 5-year-frequency rainfall yields 15,000 ton and, what is more, a lot of soil loss happens in a paddy field, a forest and a crop field. The grade map of soil loss hazard is drawn up by classifying soil loss hazard grade by 5. As a result of analyzing soil loss, the moderate area which is the soil loss hazard grade 2 takes up the largest part, 72.8% of the total soil loss hazard area, on the contrary, the severe soil loss hazard area takes up only $1,038km^2$ (1.1%) of the whole area. The severe soil loss hazard area by land cover shows $93.5km^2$ in a bare land, $168.1km^2$ in a grass land and $327.4km^2$ in a crop field respectively.

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Exploiting W. Ellison model for seawater communication at gigahertz frequencies based on world ocean atlas data

  • Tahir, Muhammad;Ali, Iftikhar;Yan, Piao;Jafri, Mohsin Raza;Jiang, Zexin;Di, Xiaoqiang
    • ETRI Journal
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    • v.42 no.4
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    • pp.575-584
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    • 2020
  • Electromagnetic (EM) waves used to send signals under seawater are normally restricted to low frequencies (f) because of sudden exponential increases of attenuation (𝛼) at higher f. The mathematics of EM wave propagation in seawater demonstrate dependence on relative permeability (𝜇r), relative permittivity (𝜀r), conductivity (𝜎), and f of transmission. Estimation of 𝜀r and 𝜎 based on the W. Ellison interpolation model was performed for averaged real-time data of temperature (T) and salinity (S) from 1955 to 2012 for all oceans with 41 088 latitude/longitude points and 101 depth points up to 5500 m. Estimation of parameters such as real and imaginary parts of 𝜀r, 𝜀r', 𝜀r", 𝜎, loss tangent (tan 𝛿), propagation velocity (Vp), phase constant (𝛽), and α contributes to absorption loss (La) for seawater channels carried out by using normal distribution fit in the 3 GHz-40 GHz f range. We also estimated total path loss (LPL) in seawater for given transmission power Pt and antenna (dipole) gain. MATLAB is the simulation tool used for analysis.

Analysis of Cell to Module Loss Factor for Shingled PV Module

  • Chowdhury, Sanchari;Cho, Eun-Chel;Cho, Younghyun;Kim, Youngkuk;Yi, Junsin
    • New & Renewable Energy
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    • v.16 no.3
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    • pp.1-12
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    • 2020
  • Shingled technology is the latest cell interconnection technology developed in the photovoltaic (PV) industry due to its reduced resistance loss, low-cost, and innovative electrically conductive adhesive (ECA). There are several advantages associated with shingled technology to develop cell to module (CTM) such as the module area enlargement, low processing temperature, and interconnection; these advantages further improves the energy yield capacity. This review paper provides valuable insight into CTM loss when cells are interconnected by shingled technology to form modules. The fill factor (FF) had improved, further reducing electrical power loss compared to the conventional module interconnection technology. The commercial PV module technology was mainly focused on different performance parameters; the module maximum power point (Pmpp), and module efficiency. The module was then subjected to anti-reflection (AR) coating and encapsulant material to absorb infrared (IR) and ultraviolet (UV) light, which can increase the overall efficiency of the shingled module by up to 24.4%. Module fabrication by shingled interconnection technology uses EGaIn paste; this enables further increases in output power under standard test conditions. Previous research has demonstrated that a total module output power of approximately 400 Wp may be achieved using shingled technology and CTM loss may be reduced to 0.03%, alongside the low cost of fabrication.