type-II-censoring

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A New Approach to Hybrid Censoring

A New Approach to Hybrid Censoring

2.3 Sequential Order Statistics 31 In realtime models the experimenter might like to adapt the number of progressively censored components during the experiment (see, e.g., Balakrishnan and Cramer , 2014 , Chapter 6). This procedure is not covered by conventional Type-II progressive censoring, where the censoring plan R is assumed to be prefixed. This issue was among others ad- dressed by Ng et al. ( 2009 ). They presented a censoring model, called adaptive Type-II progressive censoring, which enables an adjustment of the censoring plan during the ex- periment. The adaptive progressive Type-II censoring scheme proceeds as follows: if the mth failure has not been observed till a prefixed time T , then the censoring plan will be accordingly modified, in order to achieve a soon termination of the experiment. If the mth failure occurs before T , then the initially planned censoring plan R is applied. General- izations of this model have been presented in Cramer and Iliopoulos ( 2010 ), Bairamov and Parsi ( 2011 ) and Kinaci ( 2013 ). For a review on adaptive progressive censoring, we refer to
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Progressive Censoring and Stage Life Testing

Progressive Censoring and Stage Life Testing

Quality management of products is an important subject for many companies. Manu- facturers have to monitor and improve the product quality of, e.g., individual compo- nents, units, objects, or items. In particular, the lifetime of products is a relevant quality characteristic that producers have to supervise. This ‘larger-the-better’ quality charac- teristic can be controlled by an experimenter with a reliability experiment, where n ∈ N identical objects are simultaneously placed on a life test. One difficulty is, that it is not al- ways possible to observe the failure times of all objects on test. Sometimes the experimenter has to remove items intentionally because of restrictions (e.g., time, money, or material re- sources) or items are lost accidentally before failure (e.g., accidental breakage of an item). The intentional withdrawing of objects from a running life test enables the release of units for other experiments. These scenarios can be modeled by a progressive censoring model. Two well-known censoring models are progressive Type-I censoring and progressive Type-II censoring. In Type-I censoring models (time-based censoring), the life test stops at a prespecified time, and in Type-II censoring models (failure-based censoring), the life test stops after observing a prespecified number of units (cf. Mann et al. , 1974 , p. 161).
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A New Approach to Hybrid Censoring

A New Approach to Hybrid Censoring

view on the exponential distribution as well as for a reference work for possible applications, we refer to Balakrishnan and Basu ( 1995 ). Uniform distributions are often used for quantile transformations. E.g., results for pro- gressively Type-II censored order statistics have been established in Balakrishnan and Dembi´ nska ( 2008 , 2009 ) and Balakrishnan and Cramer ( 2014 , Chapter 2). Further, Kamps and Cramer ( 2001 ) considered with generalized order statistics a more general setting. Elandt-Johnson and Johnson ( 1980 , Sections 3.10, 4.6 and 5.10) were one of the first to mention the uniform distribution in the context of lifetime experiments. Weissman and Cohen ( 1996 ) considered one-parameter uniform distributed failure times under random censoring. They established some basic model-specific results and considered likelihood in- ference. In the context of general progressive Type-II censoring from uniform distributions, Aggarwala and Balakrishnan ( 1998 ) presented some exact distributional results and con- sidered the MLEs for the one-parameter as well as for the two-parameter case. Bayesian inferential results w.r.t. random censoring from the one-parameter uniform distribution have been established in Liang ( 2008 ) and Liang and Huang ( 2009 ). Hybrid censoring pro- cedures have apparently not been considered for the uniform distribution so far. However, Ng et al. ( 2015 ) established formulas for the conditional moments of progressively Type- II censored order statistics under a time constraint. Among others, explicit formulas for the standard uniform distribution have been presented. Ng et al. ( 2015 ) stated further, that these formulas can be applied in the context of Type-I progressive hybrid censoring. Further distributional properties w.r.t. ordered data from uniform distributions have been established in Balakrishnan and Cramer ( 2014 , Chapter 2), for ordinary and progressively Type-II censored order statistics, and in Bieniek ( 2007 ), for generalized order statistics.
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RELATIONS FOR MOMENTS OF PROGRESSIVELY TYPE-II RIGHT CENSORED ORDER STATISTICS FROM ERLANG-TRUNCATED EXPONENTIAL DISTRIBUTION

RELATIONS FOR MOMENTS OF PROGRESSIVELY TYPE-II RIGHT CENSORED ORDER STATISTICS FROM ERLANG-TRUNCATED EXPONENTIAL DISTRIBUTION

test at some prefixed or random inspection times. It allows for both failure and time censoring. Many modifications of the standard model have been developed, but the basic idea can be easily described by progressive Type-II censoring, which can also be considered as the most popular model. Under this scheme of censoring, from a total of n units placed simultaneously on a life test, only m are completely observed until failure. Then, given a censoring plan (R1 , R 2 , · · · , Rm):

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Type-II Shell Evolution in 98Zr

Type-II Shell Evolution in 98Zr

Since naturally-existing atomic nuclei can be made up of up to ∼300 nucleons (neutrons and protons), the nuclear forces extracted from QCD for light nuclei can only be generalized to some limited extent [13]. In practice, mainly their general characteristics are accounted for. Those are a strongly attractive effect between nucleons at small distances (∼one femtometre [fm]), which rapidly decreases to negligibility (¦2.5 fm), and a strong repulsion at close distances (®0.7 fm) [10, 14]. To predict the resulting nuclear properties analytically, solving the result- ing many-body two-type quantum fluid is then required; which, computationally, can get as challenging as the description might suggest. A phenomenological ap- proach is the systematic modelling of the effective nuclear force in dependence on the nucleons composing a nuclei. For this systematic perspective the nuclei are best represented on the chart of nuclides, i.e. as two-dimensional graph with neutron (N ) and proton number (Z) as abscissa and ordinate. This is depicted in figure 1.1 for experimentally observed nuclei (noteworthy, only ∼3600 of ∼6000 theoretically predicted [15]).
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SFCA-II type Ca2.46Fe3+8.57 Fe2+0.52Al5.45O24 - an improved structural model for an iron-ore sinter phase

SFCA-II type Ca2.46Fe3+8.57 Fe2+0.52Al5.45O24 - an improved structural model for an iron-ore sinter phase

, Z = 4. Structure determination and subsequent least-squares refinements resulted in a residual of R(|F|) = 0.0349 for 7406 independent reflections and 773 parameters. Site occupancy refinements on the 35 octahedral (M) and tetrahedral (T) positions in the asymmetric unit were aided by crystallochemical considerations and the assumption of charge balance between the cations and anions. The derived formula compares well with the outcome of electron microprobe studies. The crystal structure of SFCA-II shows the typical features of the SFCA-family. It can be built from an alternating sequence of two different types of fundamental layers. For SFCA-II, they are oriented parallel to (100). Layer-type I is solely based on [MO 6 ]-octahedra (M: Ca, Fe 3+ , Al) forming individual five polyhedra wide bands. Within a single band, the octahedra share common edges. Layer-type II, on the other hand, contains [MO 6 ]-octahedra as well as [TO 4 ]-tetrahedra (T: Al, Fe 3+ , Fe 2+ ). By corner sharing each [MO 6 ]-group is linked to two adjacent tetrahedra into [MT 2 O 12 ]-clusters or “winged octahedra”. Linkage between neighboring strips of these moieties is provided by additional [TO 4 ]-tetrahedra arranged in vierer single-chains. Our investigation rectifies previous studies on SFCA-II where wrong atomic coordinates have been published.
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Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

For sample size calculation an implant failure rate of 5 % for group 1 (implant loading after a post-surgical healing period of 12 weeks) an implant failure rate of 25 % for group 2 (early implant loading within 1 week post implantation) was assumed. Based on 0.8 power to detect a significant difference at the two sided 5% level with an assumed loss to follow-up of 5 %, 62 patients in each group and 124 in total will be required. Sample size calcu- lation, which based on clinical experiences with the new Orthosystem type II and early functional loading of con- ventional dental implants, was estimated with nQuery Advisor ® (Version 3.0) by the Institute of Medical Biosta- tistics, Epidemiology and Informatics (WH), University of Berlin, Germany.
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Novel Dinucleating Ligand Systems Containing Two Adjacent Coordination Compartments of the Potential Triamidoamine-Type -Nickel(II) and Cobalt(II) Coordination Chemistry 

Novel Dinucleating Ligand Systems Containing Two Adjacent Coordination Compartments of the Potential Triamidoamine-Type -Nickel(II) and Cobalt(II) Coordination Chemistry 

When H 5 L 4 is treated with the same metal salts in the absence of an external base, different com ­ plexes with empirical formula H 4 LNi 2 C lvH Cl and H 4 LC 0 2 CI 3 HCI are formed due to the presence of one additional equivalent of HC1. Again, mag­ netic moments per metal ion at room temperature of 3.21 ± 0 .0 1 (H 5 L 4 Ni 2 Cl4) and 4.39 ± 0.05 (H 5 L 4 Co 2 C14) confirm the presence of high- spin nickel(II) and cobalt(II), respectively. Unique structures in the solid state were revealed by X-ray diffraction analyses for both of these systems.
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Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

Methods/Design: The intended study is designed as a prospective, multicenter randomized controlled trial (RCT), comparing and contrasting the effect of early loading of palatal implant therapy versus implant loading after 12 weeks post implantation using the new ortho-implant type II anchor system device (Orthosystem Straumann, Basel, Switzerland). 124 participants, mainly adult males or females, whose diagnoses require temporary stationary implant-based anchorage treatment will be randomized 1:1 to one of two treatment groups: group 1 will receive a loading of implant standard therapy after a healing period of 12 week (gold standard), whereas group 2 will receive an early loading of orthodontic implants within 1 week after implant insertion. Participants will be at least followed for 12 months after implant placement.
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Carnitine supplementation to obese Zucker rats prevents obesity-induced type II to type I muscle fiber transition and favors an oxidative phenotype of skeletal muscle

Carnitine supplementation to obese Zucker rats prevents obesity-induced type II to type I muscle fiber transition and favors an oxidative phenotype of skeletal muscle

Obesity- and diabetes-induced type I to type II fiber transition and decreases of oxidative capacity of skeletal muscle has been explained by down-regulation of per- oxisome proliferator-activated receptor γ, coactivator-1α (PGC-1α) and peroxisome proliferator-activated receptor δ (PPARδ) [4,9,14]. Both, PGC-1α and PPARδ are crit- ical regulators of genes involved in type II to type I fiber transition, mitochondrial biogenesis, cellular and mito- chondrial fatty acid uptake, β-oxidation, carnitine up- take, tricarboxylic acid cycle, respiratory chain, and angiogenesis [15-20]. Due to these functions PPARδ and PGC-1α are typically higher expressed in oxidative type I muscle fibers than in glycolytic type II muscle fibers [15,21]. Interestingly, carnitine supplementation was reported to increase expression of PGC-1α and PPARδ in rodent models of unloading [4], and genetic and diet- induced obesity and diabetes [10]. Based on these obser- vations we hypothesized that carnitine supplementation through inducing PGC-1α and PPARδ in skeletal muscle counteracts obesity and/or diabetes-induced muscle fiber transition from type I to type II and restores the muscle fiber distribution and the muscle oxidative meta- bolic phenotype observed during non-obese and non- diabetic states. As a model object we used obese Zucker rats, an established genetic model of obesity, insulin re- sistance, and metabolic syndrome, which were fed either a carnitine supplemented or a control diet with a low native carnitine concentration for 4 wk. Lean Zucker rats served as healthy non-obese and non-diabetic controls.
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Erdalkaliquadratate, II SrC40 4 * 3 H20 Typ I [1] Alkaline-Earth Squarates, II SrC40 4 -3 H 20 Type I [1] 

Erdalkaliquadratate, II SrC40 4 * 3 H20 Typ I [1] Alkaline-Earth Squarates, II SrC40 4 -3 H 20 Type I [1] 

In SrC40 4-3 H 20 (type I), Sr2+ has CN 8. It is surrounded by 3 w ater m olecules and 5 oxygen atom s of 4 different squarate dianions. The C - O and C - C bond lengths are typical of extensive delocalization of the jr-electron system. The connection of Sr2+ and C40 42" leads to infinite layers, obviously interlinked by hydrogen bonding.

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Ethiopian journalism from self-censoring to silence: a case of reporting on internal conflict

Ethiopian journalism from self-censoring to silence: a case of reporting on internal conflict

Although the right to freedom of expression, which is a universal and basic hu- man right, is provided for citizens by the Ethiopian Constitution, journalists in the country live under fear while exercising this right, specifically in the case of report- ing on internal conflicts. The intensity of the journalists’ fear and the subsequent self-censorship has been widely, and perhaps, exceedingly observed on issues relat- ed to internal conflicts, in particular with, ethnic conflicts. The newspapers’ overall under coverage of internal conflicts and their heavy dependence on external news agencies can be a reflection of journalists` fear and self-censorship. This situation appears to have led the media to shift from self-censoring to a silence. This phenom- enon directly limits the society to get neutral information from the media with re- spect to internal conflicts. It also puts a question mark on the ability of the media in promoting freedom of expression since newspapers conceal some of the sensitive cases from the public.
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Inhibition of Photosystem II by Ioxynil in Wild Type and Resistant Mutant of Synechocystis 6714 

Inhibition of Photosystem II by Ioxynil in Wild Type and Resistant Mutant of Synechocystis 6714 

Results Characterization of inhibition by ioxynil of Synecho­ cystis 6714 wild type cells To determine inhibition by ioxynil on the acceptor side, i.e., the inhibition of Q A to Q B electron trans­ fer, we measured fluorescence inductions (Fig. la). It is known that chlorophyll fluorescence yield is con­ trolled by the redox state of Q A. In our conditions, in the absence of herbicide, the fluorescence did not rise much above the initial F0 level because, at 440 nm, photosystem I is preferentially excited and very few centers are in the Q A~ state. Addition of herbicide produced an increase of variable fluores­ cence quasi proportional to the number of PS II cen­ ters blocked by the herbicide.
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On the effective theory of type II string compactifications on nilmanifolds and coset spaces

On the effective theory of type II string compactifications on nilmanifolds and coset spaces

a tion for the four type IIB stati SU(2)-stru ture ompa ti ations on oset spa es. However, for three of these type IIB models we found a T-duality relating them to type[r]

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Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

The OD-graphs (fig. 4.2 a) have been used to determine the precise concentrations of nanocrystals in each sample. This allows for correction of the small concentration variations observed. We fitted the OD-curve of the hybrid sample with a least square fit (broken line, fig. 4.2 a) by linear superposition of both reference OD-graphs. Thus, from the fitting coefficients we obtained the relative concentration differences between hybrid and reference samples. This relative concentration variation has been applied to rescale the PL-intensities of the reference samples in fig. 4.2 b (according chapter 3.3.2). A quenching of 63 % was obtained for the CdTe567 PL-emission in the hybrid sample (fig. 4.2 b). Hence, we can conclude that the PL of CdTe567 is quenched due to charge separation induced by electron transfer from CdTe567 to CdSe529. We can assume that energy transfer (see chapter 2.3.4) from CdTe567 to CdSe529 is very unlikely due to negligible spectral overlap and especially due to the unfavorable energy gaps, the smallest energy gap being located at CdTe567. Hence, energy transfer would lead to a PL-enhancement of the CdTe567 since it is the ET-acceptors. The quenching of steady state PL therefore strongly indicates charge separation in this type II aligned closely packed nanocrystal system.
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Metabolomics of Type 1 and Type 2 Diabetes

Metabolomics of Type 1 and Type 2 Diabetes

people worldwide, leading to poor health outcomes and high health care costs. High-throughput metabolomics screening can provide vital insight into the pathophysiological pathways of DM and help in managing its effects. The primary aim of this study was to contribute to the understanding and management of DM by providing reliable evidence of the relationships between metabolites and type 1 diabetes (T1D) and metabolites and type 2 diabetes (T2D). Information for the study was obtained from the PubMed, MEDLINE, and EMBASE databases, and leads to additional articles that were obtained from the reference lists of the studies examined. The results from the selected studies were used to assess the relationships between diabetes (T1D and/or T2D) and metabolite markers—such as glutamine, glycine, and aromatic amino acids—in patients. Seventy studies were selected from the three databases and from the reference lists in the records retrieved. All studies explored associations between various metabolites and T1D or T2D. This review identified several plasma metabolites associated with T2D prediabetes and/or T1D and/or T2D in humans. The evidence shows that metabolites such as glucose, fructose, amino acids, and lipids are typically altered in individuals with T1D and T2D. These metabolites exhibit significant predictive associations with T2D prediabetes, T1D, and/or T2D. The current review suggests that changes in plasma metabolites can be identified by metabolomic techniques and used to identify and analyze T1D and T2D biomarkers. The results of the metabolomic studies can be used to help create effective interventions for managing these diseases.
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On the numerical solution of a semilinear elliptic eigenproblem of Lane-Emden type, (II): Numerical experiments

On the numerical solution of a semilinear elliptic eigenproblem of Lane-Emden type, (II): Numerical experiments

Unfortunately, despite a fair amount of effort (even with the benefit of know- ing the desired outcome in advance), we failed to produce a damped or undamped Newton sequence converging t[r]

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Deriving Type Checkers

Deriving Type Checkers

more concise description of a system’s type rules. These auxiliary functions are not necessarily specified in an inference rule style which yields the designer of a type system additional flexibility when defining deduction rules. We consider the notion of auxiliary functions quite useful and want to extend our model such that we allow auxiliary functions not only in a rule’s premises, but also in constraints. We even go one step further and allow auxiliary functions in constraints whose correct evaluation might depend on the solution of another constraint, i.e., we allow the definition of auxiliary functions over type variables in constraints. This requirement needs to be captured by the constraint solver accordingly, a description of the constraint solving algorithm is given in Fig. 5. To deal with constraints whose evaluation depends on the solution of another constraint the algorithm performs a dependency analysis on the given constraint set and partitions the set C such that C 1 contains all the constraints which
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Goodness of fit tests for type-II right censored data : structure preserving transformations and power studies

Goodness of fit tests for type-II right censored data : structure preserving transformations and power studies

all x ∈ (0, 1). For convenience, let U 1 , . . . , U n always denote i.i.d. uniformly distributed rv’s and U 1:n , . . . , U n:n their corresponding OS’s. Theorem 2.2 shows that we can transform a Type-II right censored sample of uniformly distributed rv’s to a complete sample of ordered uniformly distributed rv’s of a smaller sample size. Now we study whether there is a transformation with this property such that the transformed rv’s are distributed as order statistics from i.i.d. rv’s even if the underlying distribution of the original sample is not U (0, 1) but possesses an arbitrary absolutely continuous cdf F . This issue is also discussed in Fischer and Kamps (2011), where some of the statements of this chapter can be found as well.
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Comparison of Diuron-and Phenol-Type Inhibitors: Additional Inhibitory Action at the Photosystem II Donor Site 

Comparison of Diuron-and Phenol-Type Inhibitors: Additional Inhibitory Action at the Photosystem II Donor Site 

This work has been digitalized and published in 2013 by Verlag Zeitschrift für Naturforschung in cooperation with the Max Planck Society for the Advancement of Science under a Creative[r]

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