• Title/Summary/Keyword: uncertain data

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Seasonal Difference in Linear Trends of Satellite-derived Chlorophyll-a in the East China Sea (위성 해색자료에서 추정한 동중국해 클로로필 선형경향의 계절별 차이)

  • Son, Young Baek;Jang, Chan Joo;Kim, Sang-Hyun
    • Ocean and Polar Research
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    • v.35 no.2
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    • pp.147-155
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    • 2013
  • The purpose of this study is to investigate seasonal difference in linear trends in satellite-derived chlorophyll-a concentration (Chl-a) and their related environmental changes in the South Sea of Korea (SSK) and East China Sea (ECS) for recent 15 years (Jan. 1998~Dec. 2012) by analyzing climatological data of Chl-a, Rrs(555), sea surface wind (SSW) and nutrient. A linear trend analysis of Chl-a data reveals that, during recent 15 years, the spring bloom was enhanced in most of the ECS, while summer and fall blooms were weakened. The increased spring (Mar. - May) Chl-a was associated with strengthened winter (Dec. - Feb.) wind that probably provided more nutrient into the upper ocean from the deep. The causes of decreased summer (Jun. - Aug.) Chl-a in the northern ECS were uncertain, but seemed to be related with the nutrient limitation. Recently (after 2006), low-salinity Changjiang diluted water in the south of Jeju and the SSK had lower phosphate that caused increase in N/P ratio with Chl-a decrease. The decreased fall (Sep. - Nov.) Chl-a was associated with weakened wind that tends to entrain less nutrient into the upper ocean from the deep. This study suggests that phytoplankton in the ECS differently changes in response to environmental changes depending on season and region.

3R Variant of Thymidylate Synthase 5'-untranslated Enhanced Region Contributes to Colorectal Cancer Risk: A Meta-analysis

  • Lu, Min;Sun, Luhaoran;Yang, Jing;Li, Yue-Yao
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2605-2610
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    • 2012
  • Background: Studies investigating the association of 2R/3R polymorphism in the thymidylate synthase 5'-untranslated enhanced region (TSER) and colorectal cancer (CRC) risk have reported conflicting results. Thus, a meta-analysis was performed to summarize the data on the potential association. Methods: Pubmed, Embase and CBM databases were searched for all available studies. Links between the TSER 2R/3R polymorphism and CRC risk were estimated by odds ratios (ORs) with 95% confidence intervals (CIs). Results: Seven case-control studies with a total of 2723 cases and 4030 controls were included in this meta-analysis. The results showed that the 3R variant of TSER 2R/3R polymorphism contributes to CRC risk in two comparison models (OR 3R vs. 2R =1.10, 95%CI 1.02-1.18, P = 0.015; OR Homozygote comparison model = 1.22 1.04-1.43, 95%CI 1.04-1.43, P = 0.012). Subgroup analyses by ethnicity further demonstrated a contribution in Caucasians with three comparison models (OR 3R vs. 2R = 1.10, 95%CI 1.02-1.19, P = 0.015; OR Homozygote comparison model = 1.21, 95%CI 1.03-1.41, P = 0.019; OR Recessive comparison model = 1.18, 95%CI 1.05-1.33, P = 0.008). However, the association in the Asian population was still uncertain due to the limited data (all P values were more than 0.05). Conclusions: Our meta-analysis suggests that the 3R variant of Thymidylate synthase 5'-untranslated enhanced region 2R/3R polymorphism contributes to gastric cancer risk in the Caucasian population, while any association in Asian populations needs further study.

A Frequency Allocation Method for Cognitive Radio Using the Fuzzy Set Theory (퍼지 집합 이론을 활용한 무선인지 주파수 할당 알고리즘)

  • Lee, Moon-Ho;Lee, Jong-Chan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.9B
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    • pp.745-750
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    • 2008
  • In a cognitive radio based system, quality of service (QoS) for the secondary user must be maintained as much as possible even while that of the primary user is protected all he time. In particular, switching wireless links for the secondary user during the transmission of multimedia data causes delay and information loss, and QoS degradations occur inevitably. The efficient resource management scheme is necessary to support the seamless multimedia service to the secondary user. This paper proposes a novel frequency selection method based on Multi-Criteria Decision Making (MCDM), in which uncertain parameters such as received signal strength, cell load, data rate, and available bandwidth are considered during the decision process for the frequency selection with the fuzzy set theory. Through simulation, we show that our proposed frequency selection method provides a better performance than the conventional methods which consider the received signal strength only.

Online Automatic Gauge Controller Tuning Method by using Neuro-Fuzzy Model in a Hot Rolling Plant

  • Choi, Sung-Hoo;Lee, Young-Kow;Kim, Sang-Woo;Hong, Sung-Chul
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1539-1544
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    • 2005
  • The gauge control of the fishing mill is very important because more and more accurately sized hot rolled coils are demanded by customers recently. Because the mill constant and the plasticity coefficient vary with the specifications of the mill, the classification of steel, the strip width, the strip thickness and the slab temperature, the variation of these parameters should be considered in the automatic gauge control system(AGC). Generally, the AGC gain is used to minimize the effect of the uncertain parameters. In a practical field, operators set the AGC gain as a constant value calculated by FSU (Finishing-mill Set-Up model) and it is not changed during the operating time. In this paper, the thickness data signals that occupy different frequency bands are respectively extracted by adaptive filters and then the main cause of the thickness variation is analyzed. Additionally, the AGC gain is adaptively tuned to reduce this variation using the online tuning model. Especially ANFIS(Adaptive-Neuro-based Fuzzy Interface System) which unifies both fuzzy logics and neural networks, is used for this gain adjustment system because fuzzy logics use the professionals' experiences about the uncertainty and the nonlinearity of the system. Simulation is performed by using POSCO's data and the results show that proposed on-line gain adjustment algorithm has a good performance.

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The Meaning of Chemotherapy in Cancer Patients (암환자가 체험한 화학요범의 의미)

  • Park, Eun-Hee
    • Journal of Korean Academy of Nursing Administration
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    • v.4 no.1
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    • pp.151-181
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    • 1998
  • This study purports to find out the meanings of chemotherapy among cancer patients. The subjects of this study were selected from those patients who have taken chemotherapy at least twice at a hospital affiliated with a university. The twelve subjects agreed to join the present study and had no problem in communication with others. The data were collected through observations and interviews by the researcher. The phenomenological analysis method proposed by Giorgi was adopted for analyzing the data. The experiences of the subjects to chemotherapy were classified into 24 atributes. These attributes were also categorized into four groups such as hope, pain, fear, and ordea according to their meanings. The subjects expressed hope through the attributes such as "the wish for a new life." "the wish for healing." "the plasure form improvement of cancer." "the wish for being discharged form a hospital." "the interest in dietectic treatment." and "the trust in medical staff." Pain was represented by such attributes as "the physical pain", "the suffering from intravenous injection." "the discomfort of hospital environment." and "the economic burden." As for the attributes represention fear, "fear of being hospitalized." "tehr obscurity of uncertain situations." "the fear of side effects." "the fear of recurrence of cancer," "the lack of knowledge of the disease." Finally, nine attributes werw frouped to ordeal "the will endeavouring to recover cancer" "the adaptation to the present situation." "the giving up of being healthy," "the regret of the past life." "the recognition of significant others." "the physical changes." "the emotional changes." "the social changes." "the recollection of illness experiences." The above findings indicate that chemotherapy means hope, pain, fear, and ordeal to those cancer patinests under treatment. Hence, the nursing interventions for those cancer patients need to be directed to maintaining hope, alleviating pain and fear, and overcoming ordeal. There are some suggestions in achieving these goals : (1) the nurses caring for cancer patients need to understand the meaning of chemotherapy experienced by those patients, (2) a nursing specialty of intravenous injection needs to be developed, (3) interventions for providing emotional support should be devised, (4) nursing care should also be available to those cancer patients being dischaged at home.

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A Bayesian approach to replacement policy following the expiration of non-renewing combination warranty based on cost and downtime (비재생혼합보증이 종료된 이후의 비용과 비가동시간에 근거한 교체정책에 대한 베이지안 접근)

  • Jung, Ki-Mun
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.5
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    • pp.873-882
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    • 2010
  • This paper considers a Bayesian approach to replacement policy following the expiration of non-renewing combination warranty. The non-renewing combination warranty is the combination of the non-renewing free replacement warranty and the non-renewing pro-rata replacement warranty. We use the criterion based on the expected cost and the expected downtime to determine the optimal replacement period. To do so, we obtain the expected cost rate per unit time and the expected downtime per unit time, respectively. When the failure times are assumed to follow a Weibull distribution with uncertain parameters, we propose the optimal replacement policy based on the Bayesian approach. The overall value function suggested by Jiang and Ji (2002) is utilized to determine the optimal replacement period. Also, the numerical examples are presented for illustrative purpose.

Lack of Relationship of Egg White Intake with Occurrence of Leukopenia in Gynecologic Cancer Patients during Chemotherapy

  • Suprasert, Prapaporn;Aue-Aungkul, Apiwat;Pautad, Nuthaya
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1265-1267
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    • 2016
  • Egg white intake during chemotherapy is common advice for cancer patients for the prevention of leukopenia. However, the benefit is uncertain. We conducted this prospective study to identify the relationship of egg white intake for gynecologic cancer patients who received carboplatin and paclitaxel and the occurrence of leukopenia. Between January 2014 and January, 2015, 81 patients were interviewed regarding their intake of egg whites before receiving subsequent chemotherapy. The basic data, the details of egg white intake and the grade of leukopenia in the previous cycle were recorded. The mean age was 54.1 years and 80% of the patients had a diagnosis of ovarian or endometrial cancer. The patients were interviewed at cycles 1-3 in 45 cases, 4-6 in 45 cases and 7-9 in two cases. Subsequent dose reduction was found in 6.2% and granulocyte-stimulating growth factors was given at 4.9%. All the patients ate egg whites with variations in the number of eggs per day as follows: less than one (3), one to two (56), three to four (14) and five to six (8). Over 70% were recommended by nurses to eat egg whites and about 63% of patients received other supplemental food. Some 44.1% of the patients who ate less than or equal to two eggs per day and 36.4% who ate more than two eggs per day developed grade 2-4 leukopenia, P = 0.61. In conclusion, the data did not provide evidence in support of the conclusion that a greater egg white intake could significantly reduce the occurrence of leukopenia.

Application of Fuzzy Multi-criteria Decision Making Techniques for Robust Prioritization (로버스트 우선순위 결정을 위한 Fuzzy 다기준 의사결정기법의 적용)

  • Han, Bong Gu;Chung, Eun Sung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.3
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    • pp.917-926
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    • 2013
  • This study presents the feasibility of fuzzy multi-criteria decision making (MCDM) techniques for the robust prioritization of projects. It is applied to water resources planning problem. Results from weighted sum method (WSM), analytic hierarchy process (AHP), revised analytic hierarchy process (R-AHP), and TOPSIS are compared with those from Fuzzy WSM, Fuzzy, AHP, Fuzzy R-AHP, and Fuzzy TOPSIS. For the calculation, all weights on criteria and the normalized data were obtained from the same investigation. As a result, the rankings from four MCDM techniques are slightly different while those from fuzzy MCDM show the comparatively consistent ranking. Therefore, it is desirable to use fuzzy MCDM technique when MCDM is used for the prioritization problem, since fuzzy MCDM can include the uncertain variability of input data and weighting values on criteria.

Analysis on the Acupuncture Contents of the Domestic Neck Pain and HIVD-Cervical Spine Clinical Studies : a literature review

  • Mo, Min Ju;Hwang, Doo Ree;Lee, Ju Hyeon;Kim, Dong Hoo;Hwang, Seon Hye;Sohn, Soo Ah;Hwang, Ji Hoo
    • Journal of Acupuncture Research
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    • v.34 no.2
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    • pp.113-125
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    • 2017
  • Objectives : Cervical herniated intervertebral disc (HIVD) are common diseases. They can be managed with acupuncture, but the evidence for effectiveness is uncertain. This review analyzed the acupuncture studies of domestic neck pain and cervical HIVD; the purpose of this study was to provide basic data useful for future research. Methods : We investigated acupuncture treatments for neck pain and cervical HIVD by searching 5 Korean Internet databases. The keywords used were "neck pain", "HIVD-cervical spine", and "nuchal pain". A total of 53 research papers (17 case reports, 16 clinical data analyses, 11 randomized controlled trials, and 9 non-randomized controlled trials) were found and analyzed according to the publication year, type of study, treatment, use of filiform needles, and type of pharmacopuncture used acupoint. The effectiveness of acupuncture treatment was determined. Results : 1. Filiform needles have been primarily used in domestic research and were used in at least half of published pharmacopuncture studies. 2. In 51 papers using filiform needles, many studies used only local acupoints; few studies used only distant acupoints. 3. All studies using pharmacopuncture were performed using local acupoints. In particular, the studies based on A-shi point, trigger point, and radiologic lesion sites were useful for multiple purposes. Conclusion : In this study, we analyzed the acupuncture contents of the domestic neck pain and HIVD-cervical spine clinical studies. This study considers the assessment of the quality and efficacy of each study, which is likely to require research that reflects the future.

Efficacy of Herbal Medicines for the Treatment of Psoriasis : Systematic Review and Meta-analysis (건선의 한약치료 효과에 대한 체계적 문헌 고찰과 메타 분석)

  • Ryu, Deok-Hyun;Ryu, Deok-Seon;Roh, Seok-Sun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.30 no.3
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    • pp.1-19
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    • 2017
  • Objectives : This study aimed to validate the effect of herbal medicine intervention to relieve the symptoms of psoriasis using systematic review and meta-analysis and provide the newest reason of effectiveness of Korean medicine to psoriasis. Methods : Data were collected through electronic database including Pubmed, Cochrane CENTRAL, NDSL OASIS, Koreantk. Two experts assessed risk of bias of randomized controlled trials by Cochrane group's Risk of Bias tool after searching, reviewing and selecting papers. Data were analyzed using Review Manager(RevMan) 5.3 and Comprehensive Meta Analysis 2.0. Results : Total number of selected trials was 16 randomized controlled trials. This study evaluated the risk of bias and effectiveness of herbal medicine to psoriasis. There were high frequency uncertain in selection bias, performance bias and detection bias. In this meta-analysis, Korean medicine treatment was more effective than western medicine (ES:0.507, 95%CI:0.147-0.867) and placebo (ES:0.955, 95%CI:0.598-1.312). Conclusions : Herbal medicine intervention can be an effective for treatment in psoriasis. But enhancing levels of evidence, we must try to accumulate clinical researches of herbal medicine to psoriasis in Korea.