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Estimation for partially observed left truncation and right censored competing risks data from a generalized inverted exponential distribution with illustrations
No full textIn this paper, studies of competing risks model are considered when the observations are left-truncated and right-censored data. When the failure times of the competing risks are distributed by a generalized inverted exponential model with same scale but different shape parameters with partially observed failure causes, statistical inference for the unknown model parameters is discussed from classical and Bayesian approaches, respectively. Maximum likelihood estimators of the unknown parameters, along with associated existence and uniqueness, are established, and the asymptotic likelihood theory is also used to construct the confidence interval via the observed Fisher information matrix. Moreover, Bayesian estimates and the corresponding highest posterior density credible intervals are also obtained based a flexible Gamma-Beta prior, and a Gibbs sampling technique is constructed to compute associated estimates. Further, under a general practical assumption with order-restriction parameter case, classical and Bayesian estimations are also established under order restriction situations, respectively. Extensive Monte-Carlo simulations are carried out to investigate the performances of our results and two real-life examples are analyzed to show the applicability of the proposed methods.補正完畢TW
Estimation and prediction of modified progressive hybrid censored data from inverted exponentiated Rayleigh distribution
No full textIn this paper, statistical inference of an inverted exponentiated Rayleigh model is studied when the failure times are obtained under a modified progressive hybrid censoring. The maximum likelihood estimators of the model parameters together with associated existence and uniqueness are established, and approximate confidence intervals are constructed based on asymptotic theory. Alternatively, generalized point and interval estimates for unknown parameters are also constructed based on the proposed pivotal quantities for comparison. In addition, predictive intervals of remaining useful life from the inverted exponentiated Rayleigh distribution are also constructed under classical and generalized inferential approaches, respectively. Finally, extensive simulation studies are carried out to compare the performance of the proposed methods, and two real-life examples are analyzed for illustration. The numerical results indicate that both traditional likelihood and generalized inferential methods work satisfactorily, and that our proposed generalized approach appears much more appealing and are superior to classical results.補正完畢TW
A better one stage multiple comparison procedure of several treatment mean lifetimes with the control for exponential distributions under heteroscedasticity
No full textIn this article, we present a new one-stage multiple comparison procedure for exponential mean lifetimes with the control under heteroscedasticity including one-sided and two-sided confidence intervals by improving the coverage probability and average confidence length compared with the old one. Users can use these simultaneous confidence intervals to identify better-than-the-control, worse-than-the-control and not-much-different-from-the-control products in agriculture, stock market, pharmaceutical industries in terms of the mean lifetimes. In the end, one example is used to demonstrate the proposed procedure.補正完畢GB
Exploring the Effects of Online Travel Shopping on the Distribution of Travel Product Informatio
No full text補正完畢TW
New record of reusing brewing by-product for biosynthesis of prodigiosin and its novel anti-pathogen fungi via in vitro tests and molecular docking study.
No full textProdigiosin (PG)—a molecule with promising applications in many fields—was effectively biosynthesized in this study using a novel and eco-friendly fermentation substrate—i.e., beer brewing by-product (BBB). It was confirmed as a nutrient-rich substrate source of protein (22.18%), ash (10.1%), carbohydrate (1.98%), sugar, and abundant mineral elements. The cultural medium with a newly designed formula on a small flask containing 1.25% BBB/Casein (9/1), 0.025% FeSO4, and 0.125% Na2HPO4 for a notable PG yield achieved 6230 mg/L after 48 h. PG production on a bioreactor system also enhanced yield by 1.16 folds (reaching 7220 mg/L) and shortened fermentation time (only taking 10 h). This pure pigment was isolated and identified by analyzing UV/vis absorption, MALDI-TOF MS, and HPLC. The obtained PG was used for antifungal tests. Notably, in this work, most of PG’s pathogen fungal inhibition activity are new findings. Of those, PG showed the most positive effect on Colletotrichum gloeosporioides F05 strain (causing on sweet potato roots) with inhibition rates of mycelial growth and spore germination achieved at 47 and 57%, respectively. In particular, PG also reduced resistance and wholly inhibited mycelium growth germinating from spores. Furthermore, PG showed the good interaction ability with multiple target proteins (CDC42, CYP51, CAS2, Pectate lyase B, and Beta tubulin) inhibiting C. gloeosporioides via docking simulation. The results of this study revealed useful scientific information related to the novel application of BBB in PG production and the new PG’s effects in the management of fungal pathogens in crops.NSTC補正完畢US
Analyzing the Governance of Fear in Pandemic Narratives: A Case Study of the COVID-19 Pandemic
No full text以往，衛生治理是以某個國界之內的範圍來考慮，倚靠的是主權國家通過邊境控制保護其領土，以避免傳染病的入侵。然而，當今傳染病的風險跨越國家疆域，必須使用跨越國界的方式治理，即從「國家威脅管理」轉移到「全球風險治理」。恐懼治理是公共衛生重要與核心措施，動員恐懼等同於控制社會。新冠疫情敘事多置入適當程度的恐懼，在恐懼中，安全與秩序是首要價值，這意味為達到安全，民眾必須放棄部份的自由。本研究分析做為風險生產者與治理者的世界衛生組織（WHO）治理新冠疫情的方式，分析其如何運用科學證據與專家言說建構恐懼，以瞭解大流行敘事如何產生於特定的社會和政治語境中，以及在其間涉及的權力、規訓、治理等議題。補正完畢TW
Optimal recovery aircraft assignment model for aircraft grounding of a certain aircraft type
No full textThis study adopted a system optimization approach to establish a recovery aircraft allocation model to minimize flight delays. A recovery aircraft assignment model was developed that combined network flow technology and mathematical programming methods. To validate the model, tests were conducted by grounding different aircraft types using operational data from a Taiwan airline. The results show that the proposed model efficiently solves and can obtain the optimal solution within one minute. Furthermore, the tests show that a greater proportion of grounded aircraft types may disable more flights and cause delays. Various flight delay strategies were used for the sensitivity analyses. The results show that when the allowable delay time increases, the number of flights that cannot be implemented decreases. However, this decrease does not continue indefinitely after a certain allowable delay time. A similar trend is observed in the total delay time. In conclusion, the proposed model can serve as a planning assistance tool for aircraft reassignment to provide decision-makers with an essential reference.補正完畢DE
Strategies for Green Transportation While Preserving Mobility and Accessibility: A Case Study of Taipei City
No full textThis study develops a green index to evaluate the sustainability of different paths in urban transportation networks of origin-destination (OD) pairs. Urban transportation networks usually involve various transport modes and trips can be accomplished with more than one pattern. The basic functions of transportation, mobility and accessibility, are also explored based on travel time. This study provides strategies for Taipei City to shift smoothly to green transportation while preserving mobility and accessibility from both transport network and mode perspectives. A proposal is presented to connect activity and transportation networks by densely distributed convenience stores in Taipei. A Monte Carlo simulation of thousands of OD pairs in Taipei City is conducted to examine proposed strategies. The results indicate that for short trips, commuters can directly use motorcycles by renting and returning those at convenience stores of origins and destinations. For medium and long trips, electric motorcycles are promoted as green feeder modes to mass rapid transit stations.補正完畢US
基於注意模型的圖像擴展
No full textAlong the advanced progresses on deep neural networks, there are many impressive results on image inpainting. Consequently, several research are trying to transfer successful experiences into image outpainting. Contextual attention net is one of the popular architectural units being applied to outpainting. We argue that it may not as suitable when embedded in an outpainting network. Instead, we adopt SEnet for it has global receptive field and channel-wise feature recalibration. This is very helpful for image outpainting. We also propose a local discriminator mechanism to decide whether a randomly select partial image is a real one. By ‘randomness’, the generator can produce a realistic result.補正完畢國際新北市，臺灣JP
Empirical-Likelihood-Based Model Selection Criteria for Missing Longitudinal Data
No full text補正完畢國際Taipei City, TaiwanTW