• 제목/요약/키워드: Random Mesh

검색결과 54건 처리시간 0.019초

Survival Rates for Breast Cancer in Iranian Patients: a Meta-Analysis

  • Rahimzadeh, Mitra;Pourhoseingholi, Mohamad Amin;Kavehie, Behrooz
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권4호
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    • pp.2223-2227
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    • 2016
  • Background: Breast cancer is the most common cancer among Iranian women. Since development of the disease in Iranian women occurs relatively early, the survival rate matters considerably. In different countries, survival of breast cancer patients varies considerably. Therefore, the one-year, three-year, five-year, and ten-year survival rates for breast cancer in Iran were assessed using a meta-analysis. Materials and Methods: This systematic review and meta-analysis was based on valid Iranian sources including SID, MAGIRAN and IRANMEDEX, along with reliable English databases, namely, PUBMED and SCOPUS. In domestic databases, a search was conducted based on key words of breast cancer and survival rate, and in international databases, with "breast cancer" and the equivalent of "neoplasm" of Mesh Word, "survival rate" and "Iran." Then all reviewed papers and theses which met the inclusion criteria were selected for investigation. To conduct the analysis STATA 11.2 software and random-effects models were used. Results: In 24 studies, 22,745 participants were included. The one-year, three-year, five-year and ten-year survival rates were 0.956, 0.808, 0.695 and 0.559, respectively. The minimum and maximum survival rates for 5-years were 0.48 and 0.87. The average age of the onset of the disease was 48.3. Conclusions: As in Iran, since the onset of the disease is at low age, in spite of the relatively high survival rate as compared to other cancers, prevention and screening programs at early age for early stage diagnosis seems necessary.

복합 CAA 방법과 FRPM 기법을 이용한 냉장고 얼음제조용 원심팬의 광대역 소음 예측 (Broadband Noise Prediction of the Ice-maker Centrifugal Fan in a Refrigerator Using Hybrid CAA Method and FRPM Technique)

  • 허승;김대환;정철웅
    • 한국음향학회지
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    • 제31권6호
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    • pp.391-398
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    • 2012
  • 본 연구에서는 기존의 RANS(Reynolds Averaged Navier Stokes) 방정식을 이용하는 복합 CAA(Computational AeroAcoustics) 방법에 광대역 소음원 생성을 위한 FRPM(Fast Random Particle Mesh) 기법을 적용하여 원심팬 광대역 소음 예측을 수행하였다. 먼저, RANS 방정식을 이용하여 원심팬 주위의 유동장을 예측하여 주요한 소음원 영역을 추론하고, 추론된 소음원 영역에 FRPM 기법을 적용하여 통계적 특성을 만족하는 난류를 재생하였다. RANS 방정식으로부터 해석된 유동장과 FRPM 기법으로부터 재생된 유동장을 이용하여 합성한 유동장에 음향상사법(Acoustic Analogy)을 적용하여 원심팬의 소음원을 생성하였다. 생성된 원심팬의 소음원을 경계요소법(Boundary Element Method)으로 구현된 선형전파모델에 적용하여 원심팬의 광대역 소음을 예측하였다. 원심팬에 대한 소음 측정값과의 비교를 통하여 제안된 기법이 원심팬의 순음 소음 및 광대역 소음 예측에 효과적임을 확인하였다.

802.11p 기반 다중 라디오 다중채널 네트워크 환경에서 안전 메시지 전송을 위한 내쉬 협상 해법을 이용한 채널할당 (Channel assignment for 802.11p-based multi-radio multi-channel networks considering beacon message dissemination using Nash bargaining solution)

  • 권영호;이병호
    • 인터넷정보학회논문지
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    • 제15권3호
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    • pp.63-69
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    • 2014
  • IEEE 802.11p 차량 네트워크 환경 (WAVE)에서는 차량 운전자의 안전을 위해서 주기적으로 안전 메시지를 전송하도록 되어 있다. 차량 안전 메시지의 전송을 통해 도로상의 안전과 주행 효율을 제공하기 위해서 WAVE 표준에서는 멀티 채널 멀티 라디오 환경을 제안하고 있다. 그러나 WAVE 표준안은 안전메세지를 하나의 물리 디바이스에 하나의 채널을 이용하여 제어하고 전송하는 것으로 정의되어 있어서 다중 라디오 환경과 안전 메시지 전송 효율성을 고려하지 않았다. 또한 네트워크 무선상에서 서로 충돌이 일어나지 않는 채널을 할당하는 채널 할당은 네트워크 망구성방식을 잘 알고 있거나 모든 노드들이 같은 전송률을 가지는 무선 대역에 있어도 NP-hard한 문제로 잘 알려져 있다. 본 논문에서는 최신 802.11p와 1609.4 802.11p 표준을 이용해서 다중 채널 다중 라디오 WAVE 환경을 무선 메쉬 네트워크로 가정하여 Nash 협상 게임을 통해서 서로 간섭이 없는 채널을 할당하는 방법을 제안하고자 한다. 본 제안된 알고리즘은 시뮬레이션을 통해서 검증하였고 해당 알고리즘이 8채널 3 라디오 환경에서 랜덤 채널 할당 방법이나 Tabu 알고리즘 보다 효율성이 좋다는 것을 입증하였다.

Tillage Operational Analysis Based on Soil Moisture Content, Machine Speed, and Disc Space of Compact Disc Harrow

  • Okyere, Frank Gyan;Moon, Byeong Eun;Qasim, Waqas;Basak, Jayanta Kumar;Kahn, Fawad;Kang, Dae Sik;Yoon, Yong Cheol;Kim, Hyeon Tae
    • Journal of Biosystems Engineering
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    • 제43권3호
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    • pp.161-172
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    • 2018
  • Purpose: During tillage operations, the selection of a working machine (tool) depends on the soil conditions as well as the type of tillage operation to be performed. The goal of this research was to ascertain the effects of varying working machine parameters of a compact disc harrow on tillage operations under various soil moisture content (SMC) conditions. Methods: The working machine parameters were the disc spacing and machine speed. The tillage parameters under investigation were the soil inversion ratio (SIR), tillage cutting depth (TCD), and soil clod breakage ratio (SCB). To determine the SIR, the areas of the white regions before and after tillage were obtained. The ratio of the difference of the areas of the white regions before and after tillage to the area of the white regions before tillage was considered as the SIR. The SCB was obtained as the ratio of the weight of soil clods after sieving with a mesh size of <0.02 m to the total weight of the soil clods before sieving. The soil TCD was measured using a tape measure at random points after the tillage operation. The resulting data were statistically analyzed in a one-way analysis of variance. Results: The highest soil inversion was achieved when the machine speed was 0.2 m/s with the disc spaced at 0.2 m in the 16.5% SMC. At a 0.4-m/s machine speed and 0.3-m disc spacing the highest soil breakage was achieved in the 26.5% SMC. The highest TCD was achieved at a 0.2-m/s machine speed and 0.2-m disc spacing in the 16.5% SMC. Conclusions: It was concluded that varying the working machine parameters, such as the disc spacing and machine speed, could significantly affect the soil inversion and soil clod breakage; however, it had no significant impact on the TCD.