scholarly journals Preservation of phase-type distributions under Poisson shock models

1992 ◽  
Vol 24 (1) ◽  
pp. 223-225 ◽  
Author(s):  
M. Manoharan ◽  
Harshinder Singh ◽  
Neeraj Misra
Keyword(s):  
Continuous Phase ◽  
Finite Mixture ◽  
Life Distribution ◽  
Mean Values ◽  
Shock Models ◽  
Phase Type ◽  
Phase Type Distributions ◽  
Discrete Phase ◽  
The Mean ◽  
The Relationship

In this paper, we consider the life distribution H(t) of a device subject to shocks governed by a finite mixture of homogeneous Poisson processes. It will be shown that if (pk), the probabilities that the device fails on the kth shock, has a discrete phase-type (DPH) distribution, then H(t) is continuous phase-type (CPH). The relationship between the mean values of (pk) and H(t) is established.

scholarly journals Preservation of phase-type distributions under Poisson shock models

1992 ◽  
Vol 24 (01) ◽  
pp. 223-225 ◽  
Author(s):  
M. Manoharan ◽  
Harshinder Singh ◽  
Neeraj Misra
Keyword(s):  
Continuous Phase ◽  
Finite Mixture ◽  
Life Distribution ◽  
Mean Values ◽  
Shock Models ◽  
Phase Type ◽  
Phase Type Distributions ◽  
Discrete Phase ◽  
The Mean ◽  
The Relationship

In this paper, we consider the life distribution H(t) of a device subject to shocks governed by a finite mixture of homogeneous Poisson processes. It will be shown that if (pk ), the probabilities that the device fails on the kth shock, has a discrete phase-type (DPH) distribution, then H(t) is continuous phase-type (CPH). The relationship between the mean values of (pk ) and H(t) is established.

scholarly journals AB0101 THE IMPACT OF TIME SPAN TO ACHIEVE BOOLEAN REMISSION FOR MAINTAINING DISEASE ACTIVITY AFTER ACQUISITION IN RHEUMATOID ARTHRITIS PATIENT

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1079.1-1079
Author(s):  
I. Yoshii
Keyword(s):  
Rheumatoid Arthritis ◽  
Disease Activity ◽  
Disease Duration ◽  
Remission Rate ◽  
Mean Value ◽  
Time Span ◽  
Mean Values ◽  
The Mean ◽  
The Relationship

Background:Boolean remission criteria is one most popular and stringent criteria in treating patient with rheumatoid arthritis (RA), because it may guarantees a stable clinical course after attaining remission.Objectives:Impact of time span from initiation to achieving Boolean remission on maintaining disease activity, daily activities, and quality of life after attaining Boolean remission was investigated from daily clinical practice data.Methods:685 patients with RA since August 2010 under the T2T strategy were treated. They were monitored for their TJC, SJC, PGA, EGA, CRP, and disease activity indices such as CDAI, SDAI, DAS28, and Boolean criteria at every visit. HAQ-DI score, pain score using visual analog scale (PS-VAS), and EQ-5D were also monitored, and the quality of life score (QOLS) calculated from EQ-5D was determined at every visit from the time of diagnosis (baseline).Of 685 patients, 465 patients had achieved Boolean remission >1 times, and were consecutively followed up for >3 years. These patients were enrolled in the study. Time span from the first visit to first Boolean remission was calculated. The relationship between the time span and each of background parameters, and the relationship between the time span and each of the mean values of the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at the first Boolean remission and thereafter was evaluated statistically.Patients were subsequently divided into the G ≤ 6 and G > 6 groups based on the achievement of first Boolean remission within two groups: time span G ≤ 6 months and G > 6 months. The two groups were compared with regard to the SDAI score, HAQ score, PS-VAS, SHS, and QOLS at first visit and at the time of first Boolean remission, and the mean values of these parameters after remission were evaluated statistically. Moreover, changes of these parameters and the mean Boolean remission rate after the first remission, and SDAI remission rate at the first Boolean remission to thereafter were compared between the two groups statistically.Results:Out of 465 patients, females comprised 343 (73.7%), and the mean age was 67.8 years (range, from 21–95 years). The mean disease duration at first visit was 6.1 years (range, from 1 months–45 years). The mean follow up length was 88.1 months (range: 36–122 months; median: 85 months) and mean time span from the first visit to the first Boolean remission was 8.1 months. The mean SDAI score, HAQ score, PS-VAS, and the QOLS at first visit were 13.3, 0.467, 33.2, and 0.834, respectively. Among the study parameters, PS-VAS and QOLS were significantly correlated with the time span. For parameters at the first Boolean remission, HAQ-DI score, PS-VAS, and QOLS demonstrated significant correlation with the time span, whereas SDAI, HAQ-DI score, PS-VAS, SHS, and QOLS after the Boolean remission demonstrated significant correlation with the time span.The comparison between the G ≤ 6 and the G > 6 groups revealed that the disease duration, HAQ score, and PS-VAS at baseline in the G > 6 were significantly higher than that in the G ≤ 6 group, and QOLS in the G ≤ 6 group was significantly higher than that in the G > 6 group at baseline. Similarly, the HAQ score and PS-VAS at the first Boolean remission in the G > 6 group were significantly higher than that in the G ≤ 6 group, whereas QOLS in the G ≤ 6 group demonstrated no significant difference compared with that in the G > 6 group.The mean value of the SDAI score after the first Boolean remission in the G > 6 group was significantly higher than that in the G ≤ 6 group. Similarly, the SDAI score, HAQ score, and PS-VAS after the first Boolean remission in the G > 6 group were also significantly higher than those in the G ≤ 6 group, and the mean value of the QOLS in the G ≤ 6 group were significantly higher than that in the G > 6 group. The Boolean remission rate and SDAI remission rate after the first Boolean remission were significantly higher in the G ≤ 6 group than those in the G > 6 group.Conclusion:Attaining Boolean remission ≤ 6 months for RA has significant benefit for more stable disease control, that leads good maintenance of ADL.Disclosure of Interests:None declared

How landscape and climate affect the spatial variability of the Italian rainfall extremes? Some initial clues based on I2-RED

2021 ◽  
Author(s):  
Paola Mazzoglio ◽  
Ilaria Butera ◽  
Pierluigi Claps
Keyword(s):  
Spatial Variability ◽  
Linear Regression Analysis ◽  
Alpine Region ◽  
Annual Rainfall ◽  
Mean Values ◽  
Rainfall Extremes ◽  
Geomorphological Parameters ◽  
The Mean ◽  
The Relationship ◽  
Italian Territory

<p>The intensity and the spatial distribution of precipitation depths are known to be highly dependent on relief and geomorphological parameters. Complex environments like mountainous regions are prone to intense and frequent precipitation events, especially if located near the coastline. Although the link between the mean annual rainfall and geomorphological parameters has received substantial attention, few literature studies investigate the relationship between the sub-daily maximum annual rainfall depth and geographical or morphological landscape features.<br>In this study, the mean of the rainfall extremes in Italy, recently revised in the so-called I<sup>2</sup>-RED dataset, are investigated in their spatial variability in comparison with some landscape and also some broad climatic characteristics. The database includes all sub-daily rainfall extremes recorded in Italy from 1916 until 2019 and this analysis considers their mean values (from 1 to 24 hours) in stations with at least 10 years of records, involving more than 3700 stations.<br>The geo-morpho-climatic factors considered range from latitude, longitude and minimum distance from the coastline on the geographic side, to elevation, slope, openness and obstruction morphological indices, and also include an often-neglected robust climatological information, as the local mean annual rainfall.<br>Obtained results highlight that the relationship between the annual maximum rainfall depths and the hydro-geomorphological parameters is not univocal over the entire Italian territory and over different time intervals. Considering the whole of Italy, the highest correlation is reached between the mean values of the 24-hours records and the mean annual precipitation (correlation coefficient greater than 0.75). This predominance remains also in sub-areas of the Italian territory (i.e., the Alpine region, the Apennines or the coastal areas) but correlation decreases as the time interval decreases, except for the Alpine region (0.73 for the 1-hour maximum). The other geomorphological parameters seem to act in conjunction, making it difficult to evaluate, with a simple linear regression analysis, their impact. As an example, the absolute value of the correlation coefficient between the elevation and the 1-hour extremes is greater than 0.35 for the Italian and the Alpine regions, while for the 24-hours interval it is greater than 0.35 over the coastal areas.<br>To further investigate the spatial variability of the relationship between rainfall and elevation, a spatial linear regression analysis has been undertaken. Local linear relationships have been fitted in circles centered on any of the 0.5-km size pixels in Italy, with 1 to 30 km radius and at least 5 stations included. Results indicate the need of more comprehensive terrain analysis to better understand the causes of local increasing or decreasing relations, poorly described in the available literature.</p>

A closure characterisation of phase-type distributions

1992 ◽  
Vol 29 (01) ◽  
pp. 92-103 ◽  
Author(s):  
Robert S. Maier ◽  
Colm Art O'Cinneide
Keyword(s):  
Analogous Result ◽  
Finite Automata ◽  
Automata Theory ◽  
Phase Type Distribution ◽  
Exponential Distributions ◽  
Phase Type ◽  
Phase Type Distributions ◽  
Discrete Phase ◽  
Rational Sequence ◽  
Family Of Distributions

We characterise the classes of continuous and discrete phase-type distributions in the following way. They are known to be closed under convolutions, mixtures, and the unary ‘geometric mixture' operation. We show that the continuous class is the smallest family of distributions that is closed under these operations and contains all exponential distributions and the point mass at zero. An analogous result holds for the discrete class. We also show that discrete phase-type distributions can be regarded as ℝ+-rational sequences, in the sense of automata theory. This allows us to view our characterisation of them as a corollary of the Kleene–Schützenberger theorem on the behavior of finite automata. We prove moreover that any summable ℝ+-rational sequence is proportional to a discrete phase-type distribution.

scholarly journals Radiographic Measurements on Hindfoot Alignment View in 1,128 Asymptomatic Subjects

2020 ◽  
Vol 5 (4) ◽  
pp. 2473011420S0016
Author(s):  
Jun Young Choi ◽  
Jin Soo Suh
Keyword(s):  
Flat Foot ◽  
Adult Type ◽  
Hindfoot Alignment ◽  
Mean Values ◽  
Radiographic Measurements ◽  
Alignment Angle ◽  
The Mean ◽  
Asymptomatic Subjects ◽  
The Relationship ◽  
Female Subjects

Category: Hindfoot Introduction/Purpose: The primary aim of this study was to calculate the mean values of three most frequently measured parameters for hindfoot alignment determination in asymptomatic subjects - hindfoot alignment angle (HAA), hindfoot alignment ratio (HAR), and hindfoot moment arm (HMA). The secondary aim was to determine the relationship between HAR and HAA or HMA using statistical methods. Methods: From January 2014 to June 2019, a total of 1128 asymptomatic subjects were enrolled in this study. With the hindfoot alignment view by Saltzman and el-Khoury, HAA, HAR, and HMA were measured to evaluate the degree of hindfoot varus or valgus deviation. All subjects were divided into subgroups according to sex and age (<45 years old vs >=45 years old). Simple linear regression was performed to draw out the regression formula between HAR and HAA or HMA. Results: The mean HAA, HAR, and HMA for all subjects were -4.07+-3.48o, 0.21+-0.15, and -6.12+-5.22 mm, respectively. By comparing subgroups, female subjects >=45 years old showed the largest valgus deviation (-7.08+-6.34o, P=0.001). To predict HAR using HAA or HMA, the regression formulas were ‘HAR= 0.366 + 0.039 × HAA’ and ‘HAR= 0.361 + 0.025 × HMA.’ Conclusion: Under HAA, HAR, and HMA evaluation, the hindfoot alignment for asymptomatic subjects was valgus deviation. Furthermore, the degree of valgus deviation was the largest in female subjects aged 45 years or older. This can be explained as the progression of adult type flat foot deformity with aging.

scholarly journals Myeloma Proteins, Bence Jones Proteins and Normal Immunoglobulins in Multiple Myeloma

Blood ◽  
1967 ◽  
Vol 30 (3) ◽  
pp. 265-287 ◽  
Author(s):  
VINCENT CAGGIANO ◽  
JANET CUTTNER ◽  
ALAN SOLOMON
Keyword(s):  
Multiple Myeloma ◽  
Response To Therapy ◽  
Treatment Schedule ◽  
Myeloma Protein ◽  
Mean Values ◽  
Multiple Components ◽  
The Mean ◽  
Therapeutic Protocols ◽  
The Relationship ◽  
Chain Type

Abstract The relationship between the anomalous and normal immunoglobulins was studied through measurement of myeloma protein (MP), Bence Jones protein (BJP), and the normal γG, γA, γM and γD-globulin levels in a large group of patients with multiple myeloma. These determinations were made prior to and after initiation of three different therapeutic protocols. Thirteen out of 18 patients had at least a 25 per cent reduction in MP or BJP within 6 months. This response was characterized by considerable variation both in the rate and period of time before the anomalous proteins decreased. The type of response was independent of (1) light chain type (K or L) of G or A-MP, (2) heavy chain subgroup or genetic (Gm) factors of G-MP, and (3) electrophorectic mobility of the MP. The ratio among multiple components of heterogenous G or A-MP was not altered by therapy. The initial level of MP, in the case of patients with G-MP, may be one factor in the type of response observed. The rate of reduction of MP and BJP was extremely rapid in patients who received prednisone in conjunction with melphalan. It appeared that synthesis of anomalous γ-globulin components was completely suppressed with this treatment regimen. This type of response was not observed in patients treated with melphalan alone. The mean values for each of the normal immunoglobulin (IG) classes (γG, γA, γM and γD-globulin) were reduced below normal. Two classes, γA and γD-globulin, were particularly low. Prior to therapy, however, the extent of reduction of each IG class varied in an individual patient. An inverse relationship was found for γM-globulin and G-MP levels. Part of the normal γG-globulin in patients with G-MP was determined by measurement of Vi (γ2c) levels. Different patterns of response to therapy were noted for each class of IG. More commonly, the response of a normal IG was independent of the response of the anomalous protein and furthermore, could not be related to a particular treatment schedule. In some instances, therapy contributed to further suppression of normal IG levels.

scholarly journals Articular Eminence Inclination, Height, and Condyle Morphology on Cone Beam Computed Tomography

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Dilhan İlgüy ◽  
Mehmet İlgüy ◽  
Erdoğan Fişekçioğlu ◽  
Semanur Dölekoğlu ◽  
Nilüfer Ersan
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Mean Value ◽  
Cone Beam ◽  
Articular Eminence ◽  
Age And Gender ◽  
Mean Values ◽  
The Mean ◽  
And Gender ◽  
The Relationship

Aim. The aim of the present study was to examine the relationship between articular eminence inclination, height, and thickness of the roof of the glenoid fossa (RGF) according to age and gender and to assess condyle morphology including incidental findings of osseous characteristics associated with osteoarthritis (OA) of the temporomandibular joint (TMJ) using cone beam computed tomography (CBCT).Materials and Methods. CBCT images of 105 patients were evaluated retrospectively. For articular eminence inclination and height, axial views on which the condylar processes were seen with their widest mediolateral extent being used as a reference view for secondary reconstruction. Condyle morphology was categorized both in the sagittal and coronal plane.Results. The mean values of eminence inclination and height of males were higher than those of females (P<0.05). There were significant differences in the RGF thickness in relation to sagittal condyle morphology. Among the group of OA, the mean value of the RGF thickness for “OA-osteophyte” group was the highest (1.59 mm), whereas the lowest RGF values were seen in the “OA-flattening.”Conclusion. The sagittal osteoarthritic changes may have an effect on RGF thickness by mechanical stimulation and changed stress distribution. Gender has a significant effect on eminence height (Eh) and inclination.

Relation between leaf biomass and annual ring sapwood of Norway spruce according to needle age-class

1996 ◽  
Vol 26 (10) ◽  
pp. 1822-1827 ◽  
Author(s):  
Vitezslav Dvorak ◽  
Magda Oplustilova ◽  
Dalibor Janous
Keyword(s):  
Norway Spruce ◽  
Coefficient Of Determination ◽  
Leaf Biomass ◽  
Age Classes ◽  
Sapwood Area ◽  
Needle Age ◽  
Mean Values ◽  
Pipe Model ◽  
The Mean ◽  
The Relationship

The relationship between leaf biomass and sapwood area was investigated in a 35-year-old Norway spruce (Piceaabies (L.) Karst.) stand in mountainous conditions. Fifteen trees were destructively sampled to determine the needle biomass in several needle age-classes and whorls and the corresponding sapwood areas at the whorl branch bases and in stems at breast height. Leaf biomass/sapwood area ratio and specific leaf biomass (g•mm−2) were calculated for different needle age-classes and also for different positions in the vertical profile of the crown. The leaf biomass/sapwood area ratios were described by linear regression with a high coefficient of determination. Specific leaf biomass analysed in whorl branches was highest in the upper whorls but was decreasing downward through the profile; remained stable in the middle crown layer; and decreased again in the lower crown parts. Specific leaf biomass assessments for stems showed the largest and most increasing values in the youngest three needle age-classes followed by a decreasing trend of the specific leaf biomass in older needle age-classes. The mean values of specific leaf biomass were 1.08 g•mm−2 for branches and 1.02 g•mm−2 for stems. The results of our study are consistent with the "pipe model theory."

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