• 제목/요약/키워드: Delayers

검색결과 3건 처리시간 0.016초

부산광역시의 해양환경관리 자치역량 분석 (Self-Governing Capacity of Ocean Environmental Management of Busan Metropolitan City)

  • 최성두;강은숙;김상구;박상희;송영채;이경은
    • 한국항해항만학회지
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    • 제32권6호
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    • pp.515-519
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    • 2008
  • 본 연구는 해양특별시의 설치를 최고의 당면과제로 추진하고 있는 부산광역시의 해양환경관리 자치역량를 분석한 논문이며, 연구방법으로는 Lester(1990)가 주장하는 환경자치의 역량분석기법을 사용하였다. Lester(1990)의 연구방법에 따라 본 연구에서는 분석의 변수로서 자치단체장의 의지와 물적 토대 통을 사용하였다. 먼저 자치단체장의 의지를 분석한 결과, 부산광역시장과 관계공무원의 해양과 환경에 대한 관심도는 우리나라 제1의 해양토시라는 특수성에 비추어 비교적 낫은 수준이었다. 그리고 물적 토대를 측정하기 위하여 담당공무원수와 해양환경예산규모를 다른 7대 광역시와 비교한 결과, 다른 대도시에 비하여 높지 않은 수준이었다. 결론적으로 부산광역시의 해양환경관리 자치역량 수준은 퇴보형이거나 아니면 지체형에 속한다고 판단할 수 있었다.

Non-Practice of Breast Self Examination and Marital Status are Associated with Delayed Presentation with Breast Cancer

  • Ghazali, Sumarni Mohd;Othman, Zabedah;Cheong, Kee Chee;Lim, Kuang Hock;Wan Mahiyuddin, Wan Rozita;Kamaluddin, Muhammad Amir;Yusoff, Ahmad Faudzi;Mustafa, Amal Nasir
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권2호
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    • pp.1141-1145
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    • 2013
  • Delay in seeking treatment for breast cancer is a barrier to the early diagnosis and management of the disease, resulting in a poorer prognosis. We here estimated the prevalence of delayed presentation for breast cancer and identified possible influential sociodemographic factors in a cross-sectional study of 250 patients diagnosed with primary breast cancer at the Radiotherapy and Oncology Clinic in Kuala Lumpur Hospital. Data were collected by face-to-face interview using a structured questionnaire and from medical records. We examined associations between delayed presentation (presenting to a physician more than 3 months after self-discovery of a symptom) and sociodemographic characteristics, practice of breast self examination (BSE), history of benign breast disease, family history of breast cancer and type of symptom, symptom disclosure and advice from others to seek treatment using multiple logistic regression. Time from self-discovery of symptom to presentation ranged from tghe same day to 5 years. Prevalence of delayed presentation was 33.1% (95%CI: 27.4, 39.3). A significantly higher proportion of delayers presented with late stages (stage III/IV) (58.3% vs. 26.9%, p<0.001). Divorced or widowed women (OR: 2.23, 95% CI: 1.11, 4.47) had a higher risk of delayed presentation than married women and women who never performed breast self examination were more likely to delay presentation compared to those who regularly performed BSE (OR: 2.74, 95% CI: 1.33, 5.64). Our findings indicate that delayed presentation for breast cancer symptoms among Malaysian women is high and that marital status and breast self examination play major roles in treatment-seeking for breast cancer symptoms.

Near-Optimal Low-Complexity Hybrid Precoding for THz Massive MIMO Systems

  • Yuke Sun;Aihua Zhang;Hao Yang;Di Tian;Haowen Xia
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권4호
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    • pp.1042-1058
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    • 2024
  • Terahertz (THz) communication is becoming a key technology for future 6G wireless networks because of its ultra-wide band. However, the implementation of THz communication systems confronts formidable challenges, notably beam splitting effects and high computational complexity associated with them. Our primary objective is to design a hybrid precoder that minimizes the Euclidean distance from the fully digital precoder. The analog precoding part adopts the delay-phase alternating minimization (DP-AltMin) algorithm, which divides the analog precoder into phase shifters and time delayers. This effectively addresses the beam splitting effects within THz communication by incorporating time delays. The traditional digital precoding solution, however, needs matrix inversion in THz massive multiple-input multiple-output (MIMO) communication systems, resulting in significant computational complexity and complicating the design of the analog precoder. To address this issue, we exploit the characteristics of THz massive MIMO communication systems and construct the digital precoder as a product of scale factors and semi-unitary matrices. We utilize Schatten norm and Hölder's inequality to create semi-unitary matrices after initializing the scale factors depending on the power allocation. Finally, the analog precoder and digital precoder are alternately optimized to obtain the ultimate hybrid precoding scheme. Extensive numerical simulations have demonstrated that our proposed algorithm outperforms existing methods in mitigating the beam splitting issue, improving system performance, and exhibiting lower complexity. Furthermore, our approach exhibits a more favorable alignment with practical application requirements, underlying its practicality and efficiency.