• Title/Summary/Keyword: Positive operator

Search Result 210, Processing Time 0.034 seconds

A GENERAL ITERATIVE ALGORITHM FOR A FINITE FAMILY OF NONEXPANSIVE MAPPINGS IN A HILBERT SPACE

  • Thianwan, Sornsak
    • Journal of applied mathematics & informatics
    • /
    • v.28 no.1_2
    • /
    • pp.13-30
    • /
    • 2010
  • Let C be a nonempty closed convex subset of a real Hilbert space H. Consider the following iterative algorithm given by $x_0\;{\in}\;C$ arbitrarily chosen, $x_{n+1}\;=\;{\alpha}_n{\gamma}f(W_nx_n)+{\beta}_nx_n+((1-{\beta}_n)I-{\alpha}_nA)W_nP_C(I-s_nB)x_n$, ${\forall}_n\;{\geq}\;0$, where $\gamma$ > 0, B : C $\rightarrow$ H is a $\beta$-inverse-strongly monotone mapping, f is a contraction of H into itself with a coefficient $\alpha$ (0 < $\alpha$ < 1), $P_C$ is a projection of H onto C, A is a strongly positive linear bounded operator on H and $W_n$ is the W-mapping generated by a finite family of nonexpansive mappings $T_1$, $T_2$, ${\ldots}$, $T_N$ and {$\lambda_{n,1}$}, {$\lambda_{n,2}$}, ${\ldots}$, {$\lambda_{n,N}$}. Nonexpansivity of each $T_i$ ensures the nonexpansivity of $W_n$. We prove that the sequence {$x_n$} generated by the above iterative algorithm converges strongly to a common fixed point $q\;{\in}\;F$ := $\bigcap^N_{i=1}F(T_i)\;\bigcap\;VI(C,\;B)$ which solves the variational inequality $\langle({\gamma}f\;-\;A)q,\;p\;-\;q{\rangle}\;{\leq}\;0$ for all $p\;{\in}\;F$. Using this result, we consider the problem of finding a common fixed point of a finite family of nonexpansive mappings and a strictly pseudocontractive mapping and the problem of finding a common element of the set of common fixed points of a finite family of nonexpansive mappings and the set of zeros of an inverse-strongly monotone mapping. The results obtained in this paper extend and improve the several recent results in this area.

Systematic Review on Epstein-Barr Virus (EBV) DNA in Diagnosis of Nasopharyngeal Carcinoma in Asian Populations

  • Han, Bao-Lin;Xu, Xiang-Ying;Zhang, Chun-Zhi;Wu, Jian-Juan;Han, Chun-Feng;Wang, Hui;Wang, Xuan;Wang, Guang-Shun;Yang, Shu-Juan;Xie, Yao
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.6
    • /
    • pp.2577-2581
    • /
    • 2012
  • Objective: To conduct a meta-analysis to investigate the value of EBV DNA in diagnosis of nasopharyngeal cancer (NPC) in Asian populations, and provide important evidence for screening. Methods: Prospective or respective case-control or cohort studies regarding the detection role of EBV DNA for NPC were included in our study. We conducted a comprehensive literature search in PubMed, EMBASE, and the Chinese Biomedical Database (CBM database between January 1980 and March 2012. Results: A total of 18 studies with 1492 NPC cases and 2641 health controls were included. Almost of the included studies were conducted in China, and only one other conducted in Thailand. The overall results demonstrated that the pooled sensitivity, specificity, positive likelihood (+LR) and negative likelihood (-LR) were 0.73 (0.71-0.75), 0.89 (0.88-0.90), 8.84 (5.65-13.84) and 0.19(0.11-0.32), respectively. The overall EBV DNA detection showed the largest area of 0.932 under the summary receiver operator curve (SROC). The accuracy of detection by plasma for NPC (0.86) was higher than in serum (0.81), with largest areas under the SROC of 0.97 and 0.91, respectively. Conclusion: Our results demonstrated the EBV DNA detection in plasma or serum has high sensitivity and specificity in diagnosis of NPC, especially in Chinese populations with a high risk of cancer.

A Review of Human Element Issues of Remote Operators on Maritime Autonomous Surface Ships (자율운항선박의 개발 및 운용을 위한 육상 운항사의 인적요인 이슈 고찰)

  • Kim, Hong-Tae;Yang, Young-Hoon
    • Journal of Navigation and Port Research
    • /
    • v.43 no.6
    • /
    • pp.395-402
    • /
    • 2019
  • The development and operation of the MASS (Maritime Autonomous Surface Ship) is being actively discussed for more efficient and safer maritime transportation solutions. The autonomous navigation technology has positive aspects such as the prevention of marine accidents, improvement of fuel efficiency of ships and cost reduction, and negative aspects such as job loss, task change, and security problems. It is expected that there will be new human element issues such as the situation awareness of remote operators, because the shore-based control will be conducted when fully autonomous ships are in operation. In this paper, we consider major human element issues that should be factored in the development and operation of MASS, and suggest a method of HRA (Human Reliability Analysis) for P IFs (Performance Influencing Factors) of the remote operators that are expected according to the shore-based control.

Association of Serum and Salivary Tumor Necrosis Factor-α with Histological Grading in Oral Cancer and its Role in Differentiating Premalignant and Malignant Oral Disease

  • Krishnan, Rajkumar;Thayalan, Dinesh Kumar;Padmanaban, Rajashree;Ramadas, Ramya;Annasamy, Ramesh Kumar;Anandan, Nirmala
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.17
    • /
    • pp.7141-7148
    • /
    • 2014
  • Background: Oral squamous cell carcinoma (OSCC) is an important malignancy throughout the world; early detection is an important criterion for achieving high cure rate. Out of the many reported markers for OSCC, this study validated the efficacy of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in differentially diagnosing premalignant oral lesions and OSCC. Also, the study aimed to correlate the levels of salivary and serum TNF-${\alpha}$ with clinicopathologic factors. Materials and Methods: A prospective experimental laboratory study was designed. Serum and salivary samples from 100 subjects in each group of healthy control, premalignant disease (PMD) and OSCC were collected for the study following appropriate exclusion and inclusion criteria. Serum and salivary level of TNF-${\alpha}$ was analysed by enzyme linked immunosorbent assay. The data obtained were subjected to appropriate statistical analysis. Results: Increased level of both serum and salivary TNF-${\alpha}$ was observed in OSCC subjects compared to healthy control and PMD group. Receiver operator characteristic curve analysis and area under curve values showed high specificity and sensitivity for salivary TNF-${\alpha}$ in differentiating OSCC from PMD and healthy controls. There was significant increase in TNF-${\alpha}$ level in moderately and poorly differentiated lesion compared to well differentiated lesion and in stage IV of clinical stage. A positive correlation was observed only with histological grading of OSCC and TNF-${\alpha}$. Conclusions: Salivary TNF-${\alpha}$ is proved to be superior for detecting OSCC. Increase in TNF-${\alpha}$ with histological grading and clinical staging suggests a role in prognosis.

Permeation Characteristics of Hazardous Substances in Tattoo Dye using Franz Diffusion Cells (Franz Diffusion Cell을 이용한 문신용 염료 내 유해물질의 피부 투과특성 연구)

  • Park, Kyo-Hyun;Jung, Se-Hoon;Shin, Ho-Sang;Kim, Bae-Hwan
    • Journal of Environmental Health Sciences
    • /
    • v.42 no.1
    • /
    • pp.61-70
    • /
    • 2016
  • Objectives: The purpose of this study is to determine the exposure risk to tattoo components by analyzing skin absorption using the in vitro method. Tattoos are commonly used for cosmetic purposes, and the skin of not only the operator but of the people who are undergoing the cosmetic procedure is continuously exposed to hazardous chemicals. Methods: Skin permeation risk determination was conducted by the in vitro Franz diffusion cell method according to the ingredient types of tattoo dyes, such as volatile organic compounds (VOCs), non-volatile organic compounds and heavy metals, using hairless mouse full skin and human cadaver epidermis. Results: The major components with good skin penetration for each type of tattoo dye ingredient were clarified. Among the tatto dye ingredients, 1,2-Dichlorobenzene, Zn, Al, Pb and Ti showed good skin penetration. Most of the skin transmission rates were higher in hairless mouse full skin than in human cadaver epidermis. Conclusion: A possible exposure risk to hazardous substances in tattoo dyes was confirmed from this study. These results are expected to provide a positive contribution to the establishment of management regulations for tattoo dyes.

REGULARITY AND MULTIPLICITY OF SOLUTIONS FOR A NONLOCAL PROBLEM WITH CRITICAL SOBOLEV-HARDY NONLINEARITIES

  • Alotaibi, Sarah Rsheed Mohamed;Saoudi, Kamel
    • Journal of the Korean Mathematical Society
    • /
    • v.57 no.3
    • /
    • pp.747-775
    • /
    • 2020
  • In this work we investigate the nonlocal elliptic equation with critical Hardy-Sobolev exponents as follows, $$(P)\;\{(-{\Delta}_p)^su={\lambda}{\mid}u{\mid}^{q-2}u+{\frac{{\mid}u{\mid}^{p{^*_s}(t)-2}u}{{\mid}x{\mid}^t}}{\hspace{10}}in\;{\Omega},\\u=0{\hspace{217}}in\;{\mathbb{R}}^N{\backslash}{\Omega},$$ where Ω ⊂ ℝN is an open bounded domain with Lipschitz boundary, 0 < s < 1, λ > 0 is a parameter, 0 < t < sp < N, 1 < q < p < ps where $p^*_s={\frac{N_p}{N-sp}}$, $p^*_s(t)={\frac{p(N-t)}{N-sp}}$, are the fractional critical Sobolev and Hardy-Sobolev exponents respectively. The fractional p-laplacian (-∆p)su with s ∈ (0, 1) is the nonlinear nonlocal operator defined on smooth functions by $\displaystyle(-{\Delta}_p)^su(x)=2{\lim_{{\epsilon}{\searrow}0}}\int{_{{\mathbb{R}}^N{\backslash}{B_{\epsilon}}}}\;\frac{{\mid}u(x)-u(y){\mid}^{p-2}(u(x)-u(y))}{{\mid}x-y{\mid}^{N+ps}}dy$, x ∈ ℝN. The main goal of this work is to show how the usual variational methods and some analysis techniques can be extended to deal with nonlocal problems involving Sobolev and Hardy nonlinearities. We also prove that for some α ∈ (0, 1), the weak solution to the problem (P) is in C1,α(${\bar{\Omega}}$).

Piecewise Image Denoising with Multi-scale Block Region Detector based on Quadtree Structure (쿼드트리 기반의 다중 스케일 블록 영역 검출기를 통한 구간적 영상 잡음 제거 기법)

  • Lee, Jeehyun;Jeong, Jechang
    • Journal of Broadcast Engineering
    • /
    • v.20 no.4
    • /
    • pp.521-532
    • /
    • 2015
  • This paper presents a piecewise image denoising with multi-scale block region detector based on quadtree structure for effective image restoration. Proposed piecewise image denoising method suggests multi-scale block region detector (MBRD) by dividing whole pixels of a noisy image into three parts, with regional characteristics: strong variation region, weak variation region, and flat region. These regions are classified according to total pixels variation between multi-scale blocks and are applied principal component analysis with local pixel grouping, bilateral filtering, and structure-preserving image decomposition operator called relative total variation. The performance of proposed method is evaluated by Experimental results. we can observe that region detection results generated by the detector seems to be well classified along the characteristics of regions. In addition, the piecewise image denoising provides the positive gain with regard to PSNR performance. In the visual evaluation, details and edges are preserved efficiently over the each region; therefore, the proposed method effectively reduces the noise and it proves that it improves the performance of denoising by the restoration process according to the region characteristics.

A clinical comparative study between conventional and camouflaged syringes to evaluate behavior and anxiety in 6-11-year-old children during local anesthesia administration-a novel approach

  • Melwani, Anjana M;Srinivasan, Ila;Setty, Jyothsna V;Murali, Krishna D.R.;Pamnani, Sunaina S;Lalitya, Dandamudi
    • Journal of Dental Anesthesia and Pain Medicine
    • /
    • v.18 no.1
    • /
    • pp.35-40
    • /
    • 2018
  • Background: The sight of dental injection can bring about severe anxiety in children. Therefore, an alternative method that is convenient, effective, and keeps the needle hidden making it child friendly is necessary. The objective of the study was to compare the efficacy of a camouflaged syringe and conventional syringe on behavior and anxiety in 6-11-year-old children during local anesthesia administration. Methods: The study was a randomized, crossover clinical study including 30 children. Children were separated into two groups. Group 1 consisted of 15 children aged 6-8 years while group 2 consisted of 15 children aged 9-11 years. This study involved two sessions wherein all the children were injected using conventional and camouflaged syringes in separate sessions. Their behavior was assessed using the Faces, Legs, Activity, Cry, Consolability (FLACC) behavior pain scale and anxiety was assessed by measuring changes in pulse rate. Patient and operator preferences were compared. Results: The results showed a lower mean change in pulse rate and FLACC scores in the camouflaged group, suggesting a positive behavior and lesser anxiety with camouflaged syringes than with conventional syringes. Conclusions: The use of camouflaged syringes for anesthesia was demonstrated to be effective in improving the behavior of children and decreasing their anxiety, and is therefore recommended as an alternative to the use of conventional syringes for local anesthesia.

THE AMOUNT OF SOFT TISSUE CHANGE TO HARD TISSUE MOVEMENT FOLLOWING LE FORT II OSTEOTOMY (Le Fort II 골절단술을 이용한 비중안모 개선 효과에 대한 임상적 연구;경조직 이동에 따른 연조직 변화율에 대한 연구)

  • Kim, Myung-Jin;Yi, An-Na
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.22 no.1
    • /
    • pp.63-69
    • /
    • 2000
  • Le fort II osteotomy is much useful technique to correct the midfacial hypoplasia including nasomaxillary complex especilly in patient with dish face appearance. Not in simple orthognathic surgery but in Le Fort II osteotomy, the standardization of prognostic value is essential in treatment planning to achieve satisfactory postoperative results. According to pervious reports, the ratio of soft tissue change to hard tissue movements varies as to different surgical methods and different facial regions. But there are few report about the ratio of soft tissue change to hard tissue movement following Le Fort II osteotomy. So we tried to develop standarized soft tissue surgical treatment objective. We have followed up 16 patients, who had received Le Fort II osteotomy by one operator from 1990 to 1996, one year postoperatively. In cephalometrics, we used Frankfort line as horizontal reference line, and vertical reference line as one drawn from Sella to horizontal line perpendicularly. The landmarks are G to soft tissue G, N on reference line to soft tissue N, ANS to Pn and A to Sn. The results are as follows. 1. The value of soft tissue change to hard tissue movement showed positive correlation, having statistical significancy at G, N2, N3 point. 2. At G, N2, N3 point, the ratio of soft tissue change to hard tissue movement was 0.51, 0.98 and 0.80 respectively and showed statistical significancy, while at N1, ANS, A point, that was 0.72, 0.49 and 0.26 but didn't showed statistical significance. 3. This result shows much the same change of the soft tissue change to hard tissue movement on the upper nasomaxilla, and less the same change on the lower maxilla and so the Le Fort II osteotomy can be recommended as a reliable effective operation method for correction of nasomaxillary retrusion.

  • PDF

A Study on the Mutual Risk Management Between Container Terminal Operator and Shipping Company in Gwangyang Port (광양항의 컨테이너터미널 운영사와 해운선사간의 상호리스크 관리방안 연구)

  • Choi, Yong-Seok;Park, Sung-Su
    • Journal of Korea Port Economic Association
    • /
    • v.26 no.4
    • /
    • pp.168-187
    • /
    • 2010
  • The mutual risk management in port is really important for operating the enterprise between container terminals who provide port service and shipping liners who use the port service. This study is performed to contribute to obtain the competitive power of domestic shipping and harbor industry by getting solution of mutual risk management which can make Win-Win strategy on each other as an alternative idea. We suggested two kinds of management models to promote common benefits between container terminals and shipping liners. It is necessary to push positive support and cooperation from government and belonging related organizations for activating the Gwangyang port. In this study, we presented the efficient method to manage mutual risks between container terminals and shipping liners.