scholarly journals Investigation of Feller-Buncher Performance Using Weibull Distribution

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 284
Author(s):  
Ebru Bilici
Keyword(s):  
Weibull Distribution ◽  
Shape Parameter ◽  
B Value ◽  
Productivity Analysis ◽  
Volume Data ◽  
Estimation Model ◽  
Distribution Method ◽  
Timber Volume ◽  
C Value ◽  
The Right

With the advancement of technology in forestry, the utilization of advanced machines in forest operations has been increasing in the last decades. Due to their high operating costs, it is crucial to select the right machinery, which is mostly done by using productivity analysis. In this study, a productivity estimation model was developed in order to determine the timber volume cut per unit time for a feller-buncher. The Weibull distribution method was used to develop the productivity model. In the study, the model of the theoretical (estimated) volume distributions obtained with the Weibull probability density function was generated. It was found that the c value was 1.96 and the b value was 0.58 (i.e., b is the scale parameter, and c is the shape parameter). The model indicated that the frequency of the volume data had moved away from 0 as the shape parameter of the Weibull distribution increased. Thus, it was revealed that the shape parameter gives preliminary information about the distribution of the volume frequency. The consistency of the measured timber volume with the estimated timber volume strongly indicated that this approach can be effectively used by decision makers as a key tool to predict the productivity of a feller-buncher used in harvesting operations.

scholarly journals Aproksimasi Numerik Belah Dua dan Newton-Raphson pada Estimasi Parameter Distribusi Weibul

CAUCHY ◽  
2013 ◽  
Vol 2 (4) ◽  
pp. 193
Author(s):  
Indira P Kinasih
Keyword(s):  
Weibull Distribution ◽  
Numerical Approximation ◽  
Shape Parameter ◽  
Likelihood Function ◽  
Life Time ◽  
Life Distribution ◽  
Approximation Result ◽  
Failure Data ◽  
Newton Raphson ◽  
The Right

Life time distribution of warranted product, for example like automobile and photocopier is an interesting studies. Based on the fact that mostly, life distribution of warranted product is somewhat skewed to the right, this suggests that usual failure distribution such as Weibull distribution may provide a reasonable fit to the data. Related to these studies, parameter estimation is directly applicable since life distribution function is a function of parameters. There are no closed solution for Weibull likelihood function maximation. Therefore, numerical approximation could be an alternative solution. In this paper, Newton-Raphson and bisection method were employed to estimate the scale and shape parameter of Weibull distribution for photocopier failure data for since 4,5 years. Performance of those method were compared based on their approximation result and how fast they get into the solution. Data were taken from Bulmer and Eccleston (2003) research about photocopier realibility model.

Study on Sequential Compliance Method Influenced by Shape Parameter of Weibull Distribution

2011 ◽  
Vol 189-193 ◽  
pp. 4361-4364 ◽  
Author(s):  
Hong Liang Lou ◽  
Xing Lin Li ◽  
Xian Zhao Xu ◽  
Yang Ping Zhang ◽  
Zhong Hua Yu
Keyword(s):  
Weibull Distribution ◽  
Shape Parameter ◽  
Weibull Distributions ◽  
Simulation Test ◽  
Consumer’S Risk ◽  
Producer’S Risk ◽  
Rejection Probability

When sequential compliance method is used for Weibull distributions, the shape parameter is usually considered to be fixed. However, because of the life of products are determined by many factors, the shape parameter is variational in practice, that is to say, the shape parameter in the criterions is different from that in the practice. In this paper, the changes of acceptance and rejection probability are researched by the influence of shape parameter changes. Finally, by means of simulation test, changes on the shape parameter affecting on the probability of acceptance and rejection are quantitatively analyzed. As a result, the larger the gap on the shape parameter in the criterions and in the practice is, the larger the gap on the producer’s risk and the consumer’s risk.

scholarly journals Estimation of the compression strength and surface roughness of the as-built SLS components using weibull distribution

2021 ◽  
pp. 1-6
Author(s):  
Hamaid Mahmood KHAN
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Compressive Strength ◽  
Weibull Distribution ◽  
Selective Laser Sintering ◽  
Three Dimensional ◽  
Random Variable ◽  
Production Quality ◽  
Laser Source ◽  
Distribution Method

Selective laser sintering (SLS) is a process of fabrication of three-dimensional structures by fus- ing powder particles using a guided laser source. The uncertainty in the mechanical properties of the SLS parts fabricated at the same time and with the same process parameters can affect the repeatability of the SLS process. A vast difference in the mechanical properties of the concurrently processed parts can lower the production quality of the batch. Therefore, the param- eters are required to be design based on the most probable outcome of the desired properties. Weibull distribution is one such statistical-based probability distribution method to measure the likelihood of the occurrence of a value of any random variable falling within a particular range of values. Here, the Weibull distribution was used to measure the relative likelihood (90% probability) of the surface roughness and the compressive strength values of the SLS-built polyamide PA2200 components in the given sample space that was obtained from 20 random samples. The results show that the variance in the surface roughness (scan and built plane) and the compressive strength values were in the range of 6–7 μm and around 10 MPa, respectively. Moreover, the surface roughness of the two orthogonal planes with 90% reliability was measured at 14.81 μm (scan plane) and 12.15 μm (built plane). Similarly, the yield strength and the compressive strength with 90% reliability were found 25.87 MPa and 62.64 MPa, respectively.

scholarly journals Pengaruh Lokasi Geografis dan Vegetasi terhadap Sifat Fisikokimia Madu dari Ciwidey dan Bogor

2020 ◽  
Vol 1 (2) ◽  
pp. 71
Author(s):  
Emanuela Rae Alodia ◽  
Anas Bunyamin ◽  
Efri Mardawati
Keyword(s):  
Physicochemical Properties ◽  
Water Content ◽  
Sugar Content ◽  
Geographical Location ◽  
B Value ◽  
Reducing Sugar ◽  
National Standard ◽  
Color Analysis ◽  
A Value ◽  
C Value

<p><em>Physicochemical properties are one of the parameters of honey quality that impacts the sales of honey as well as the economy condition of the society in Ciwidey and Bogor. The physicochemical properties of honey are significantly influenced by the origin of the honey, including its geographical location and vegetation. This study aims to determine the physicochemical properties between multiflora honey from Ciwidey and Bogor with different source of nectar where Ciwidey honey is dominated by calliandra nectar while Bogor honey is dominated by kapok nectar. Data were analyzed with descriptive and quantitative method using independent t test for data with normal distribution (water content and reducing sugar content). Data that were not normally distributed (color analysis and acidity value) were tested non-parametrically with the Mann Whitney-U. The results showed that Bogor honey has the better physicochemical properties and meets Indonesian National Standard (Standar Nasional Indonesia, SNI) 8664:2018, with a water content of 15.15% w/w, L* values of 35.26, a* value of 28.66, b* value of 59.46, c* value of 66.01, h* value of 64.27°, reducing sugar content of 78.78% and acidity value of 35.56 mL NaOH kg-1. Phytochemical screening showed positive results on alkaloid, flavonoid, phenol and tannin, and the results of GC-MS analysis showed three significant compounds which are hydroxymethylfurfural of 48.26%, levoglucosan of 13.58% and ammonium carbamate of 9.18%.</em></p>

scholarly journals Teknologi pengolahan hasil perikanan untuk meningkatkan perekonomian petani ikan di Desa Sungai Geringging, Kecamatan Kampar Kiri, Kabupaten Kampar, Riau

2020 ◽  
Vol 2 ◽  
pp. 498-505
Author(s):  
Sukendi Sukendi ◽  
Dewita Dewita ◽  
Thamrin Thamrin ◽  
Ridwan Manda Putra ◽  
Windarti Windarti ◽  
...  
Keyword(s):  
Fish Farming ◽  
Food Products ◽  
Business Group ◽  
B Value ◽  
Snack Food ◽  
Service Activity ◽  
Group Members ◽  
C Value ◽  
Fishery Products ◽  
The Impact

The purpose of this community service activity is to provide knowledge and technology to the community from the Sinar Mentari Business Group, Sungai Geringging Village, Kampar Kiri District, Kampar Regency, in terms of processing fishery products into snack food products in the form of fish brains, fish dragon feet, and processing methods. packing and the process of presenting the resulting product better. The method used is the method of lectures, discussions, and direct practice on how to process fishery products. The results of this evaluation found that there had been a change in knowledge of 6 members of the Sinar Mentari Business Group, which showed that 5 people (83.33%) had been able to absorb the material given with a very good predicate (grade A), 1 person (16.67 %) can absorb the material given with a good predicate (B value), while those who get a sufficient predicate (C value) and poor predicate (D value) are not found. Based on the results of this evaluation, it is known that the skill level of the members of the Sinar Mentari Business group, it turns out that they have been able to process fishery products into snack food products in the form of fish brains, fish dragon legs and the process of packing as well as the process of presenting products independently and better. Meanwhile, the impact of this activity is that the housewives of Karya Mandiri Cultivator Group members have succeeded in having side activities to help their family's economy in the form of processing fish farming products.

Germination of Aristida armata Under Constant and Alternating Temperatures and Its Analysis With the Cumulative Weibull Distribution as a Model

1987 ◽  
Vol 35 (5) ◽  
pp. 581 ◽  
Author(s):  
RF Brown
Keyword(s):  
Weibull Distribution ◽  
Shape Parameter ◽  
Germination Rate ◽  
Coefficient Of Determination ◽  
Its Analysis ◽  
Minimal Distortion ◽  
Different Temperatures ◽  
Fitted Function ◽  
Extremes Of Temperature

Germination of Aristida armata was compared at different temperatures on a thermogradient plate. Temperatures ranged from 10°C to 50°C with day/night differentials of 0, 5, 10 and 15°C. Alternating temperatures improved overall germination, particularly at the extremes of temperature. Average temperatures of 35°C and higher were fatal to many seeds. Day temperatures of 17.5°C and lower inhibited germination but did not prevent subsequent germination under warmer conditions. There was little variation in the rate of germination with incubation under constant temperatures. Under alternating temperatures, maximum germination occurred at lower temperatures than those under which germination rate was greatest. A four-parameter cumulative Weibull distribution was used to summarise cumulative germination. The distribution has the general form: Y = M(1-exp[- {k(t - I)}c]), where Y is the total germination at time t, M is the final total germination, k is germination rate, I is the interval between the start of incubation and the start of germination, and c is a shape parameter. In nearly all cases, the fitted function had a coefficient of determination greater than 0.98. The Weibull distribution allows reconstruction of the original germination data with minimal distortion and its use is recommended for both the analysis and modelling of germination responses.

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