scholarly journals Optimal Buffer Allocation For Unpaced Balanced And Unbalanced Mean Processing Time

2012 ◽  
Author(s):  
Zalinda Othman ◽  
Shahrul Kamaruddin ◽  
Mohd. Shihabudin Ismail
Keyword(s):  
Key Words ◽  
Coefficient Of Variation ◽  
Production Line ◽  
Processing Time ◽  
Simulation Method ◽  
Buffer Allocation ◽  
Throughput Rate ◽  
Processing Times ◽  
The Mean

Artikel ini membincangkan peruntukan penampan optimum untuk talian pengeluaran unpaced yang pendek dan boleh diharap (tiada mesin rosak). Parameter utama yang mempengaruhi talian dalam kajian ini adalah min masa pemprosesan (μ) dan pekali variasinya (Cv). Lapan taburan min masa pemprosesan telah dikaji. Setiap taburan dipadankan dengan 15 konfigurasi peruntukan penampan. Kaedah simulasi digunakan bagi menganggar kadar keluaran talian untuk setiap kes. Keputusan kajian menunjukkan peruntukan penampan tertentu mempengaruhi kadar keluaran talian. Bagi talian yang boleh diharap dan min seimbang, peruntukan penampan yang optima adalah dengan mengagihkan bilangan penampan secara sama rata ke setiap slot penampan. Jika penampan tambahan diperlukan selepas agihan dilakukan, letakkan penampan tambahan tersebut pada slot penampan yang di tengah. Manakala bentuk peruntukan penampan yang baik bagi talian yang mempunyai min tidak seimbang (dengan anggapan setiap stesen mempunyai Cv tetap dan boleh diharap) ialah mengikut bentuk taburan min masa pemprosesan talian tersebut. Kata kunci: Talian pengeluaran unpaced, min tidak seimbang, peruntukan penampan optima, talian seimbang, talian pengeluaran unpaced boleh diharap This article discusses an optimal buffer allocation for short unpaced production line and it is assumed reliable (no machines breakdown). The main parameters that affect the line are mean processing time (μ) and its coefficient of variation (Cv). Eight different mean processing time distributions were studied. Each distribution was matched with 15 different buffer allocations. Simulation method was used to estimate the line throughput rate. The results showed that the allocation of buffers affect the throughput rate. For a reliable and balanced line, the optimum buffer allocation is by equally distributing the number of buffers to each buffer slot. In the case of an extra buffer is needed after equally distribution, it is placed at the center buffer slot. Meanwhile, the best buffer allocation shape for a line with unbalanced mean (with the assumption that each station is having fixed Cv and is reliable) follows the shape of the mean processing times of that line. Key words: Unpaced production line, unbalanced mean, optimal buffer allocation, balanced line, reliable unpaced production line

A Management Guide for Determination of Optimal Buffer Allocation in Unpaced Production Line Using 6 Steps OBA

2015 ◽  
Vol 793 ◽  
pp. 637-641 ◽  
Author(s):  
Mohd Shihabudin Ismail ◽  
M.I. Hussain ◽  
Zuraidah M. Zain ◽  
Noorhafiza Muhd
Keyword(s):  
Production Line ◽  
Processing Time ◽  
Simulation Method ◽  
Allocation Problem ◽  
Buffer Size ◽  
Assembly Process ◽  
Buffer Allocation ◽  
Throughput Rate ◽  
Simulation Results

This paper deals with a buffer allocation problem in unpaced μ-unbalanced production line. Unpaced line is referred to a line with workstations act independently and the material is not pulled by demand but in push mode. In this study, the production line is considered unpaced, μ-unbalanced but reliable. Mean processing time (μ) is the most difficult variable to fix constant in an actual production line due to the complexity of assembly process. The unbalance variance will become higher if the assembly process is more complex. The optimal buffer allocation need to be found for this particular type of production line so that it can maximize throughput rate and minimize total number of work-in-progress (WIP) on the line. This paper used a simulation method to simulate the throughput rate by given sets of buffer size. Based on the simulation results, a basic optimal buffer allocation (OBA) concept represented the characteristics of OBA for a production line was summarized. By applying the concept, a development of 6 Steps OBA tool is carried out. This tool could be utilized by a management in allocating the buffer during designing of the line layout.

Buffer Allocation Using 6 Steps Oba Method: A Case Study

2015 ◽  
Vol 815 ◽  
pp. 287-292
Author(s):  
M.S. Ismail ◽  
Noorhafiza Muhammad ◽  
M.I. Hussain ◽  
Zuraidah Mohd Zain ◽  
R. Ahmad
Keyword(s):  
Production Line ◽  
Processing Time ◽  
Simulation Software ◽  
Buffer Allocation ◽  
Maximum Throughput ◽  
Throughput Rate ◽  
Actual Production ◽  
Mathematical Relation ◽  
The Mean

This paper utilized a simulation software to determine an optimal buffer allocation for any unpaced production line when a set of buffer quantity is known. The optimal buffer allocation will give the highest throughput rate (productivity) to the production line. From the simulation result, a trend of relation between mean processing time (μ) trend of the stations in the production line and buffer allocation configuration of the buffer slots were studied. It was concluded that for any unpaced production line, the best throughput rate of the production line will be obtained if the buffer allocation configuration follow the mean processing time (μ) trend. By applying this concept, a mathematical relation was formed results in a development of a technique called 6 Steps OBA (optimal buffer allocation) method . In order to validate the result from this 6 Steps OBA method, a case study was carried out in one of the multinational electronics company in Malaysia (Company S). An unpaced and u-unbalanced production line was selected and this line was producing a product which is known as model A. In this production line, a few possible buffer allocations quantity were allocated on each buffer slots including buffer allocation suggested by 6 Steps OBA method. For each buffer allocation possibilities, the actual production line productivity (throughput rate) was recorded and compared to validate that the best line throughput rate was the buffer allocation suggested by the 6 Steps OBA method. From the overall result, it was proven that the 6 Steps OBA method will give a maximum throughput rate to a production line.

scholarly journals Balance capacity with variability caused by human factor: an application in a line with Monte Carlo simulation

2016 ◽  
Vol 7 (5) ◽  
pp. 643
Author(s):  
Augusto Sandes Mendes ◽  
Adriano Maniçoba da Silva ◽  
Luiz Teruo Kawamoto Júnior
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Production Line ◽  
Processing Time ◽  
Human Factor ◽  
Current Situation ◽  
Processing Times ◽  
Productive Process ◽  
Full Capacity ◽  
Total Capacity

The variation in processing times due to the human factor between the working stations of a production line can generate queues resulting in a higher cost to the productive process. The objective of this study was to apply Monte Carlo simulation to balance the capacity of a production line with stations suffering variability in processing time due to the human factor. Simulations of the current situation of the production line were performed by comparing it with a proposal to align capacity with the production restriction in order to reduce inventories process while maintaining full capacity of the line. To develop the study, the selection involves the case of a company’s production line in the metal industry that produces machinery and products for metalworking area. The results allowed pointing suggestions for the company to reduce in-process inventory, keeping then total capacity of the line.

A new tool for rapid development of electron microscopy negatives and micrographs: Initial impressions of the MOHR/PRO-8 processor

1992 ◽  
Vol 50 (2) ◽  
pp. 972-973
Author(s):  
James C. Long
Keyword(s):  
Electron Microscopy ◽  
Processing Time ◽  
Rapid Development ◽  
Processing Times ◽  
Initial Impressions ◽  
Transport Method

Over the years, many techniques and products have been developed to reduce the amount of time spent in a darkroom processing electron microscopy negatives and micrographs. One of the latest tools, effective in this effort, is the Mohr/Pro-8 film and rc paper processor.At the time of writing, a unit has been recently installed in the photographic facilities of the Electron Microscopy Center at Texas A&M University. It is being evaluated for use with TEM sheet film, SEM sheet film, 35mm roll film (B&W), and rc paper.Originally designed for use in the phototypesetting industry, this processor has only recently been introduced to the field of electron microscopy.The unit is a tabletop model, approximately 1.5 × 1.5 × 2.0 ft, and uses a roller transport method of processing. It has an adjustable processing time of 2 to 6.5 minutes, dry-to-dry. The installed unit has an extended processing switch, enabling processing times of 8 to 14 minutes to be selected.

KNOWLEDGE, ATTITUDE AND PRACTICES OF CARETAKERS AND HEALTH PROFESSIONALS TOWARD TEETHING IN INFANTS

2011 ◽  
pp. 52-59
Author(s):  
Binh Bao Son Bui
Keyword(s):  
Sleep Disturbance ◽  
Key Words ◽  
Breast Feeding ◽  
Health Professionals ◽  
Feeding Problems ◽  
Central Hospital ◽  
Pediatric Department ◽  
Correct Knowledge ◽  
The Mean

Objective and methods: a prospective questionnaire based study on 71 parents (caretakers) of consecutive children treated at the Pediatric Department, Hue Central Hospital and on 47 health professionals at the department was conducted from September until December 2009 to investigate the knowledge, attitude and practices of the caretakers, nurses and postgraduated doctors toward teething in infants. Results: Most responders believed that teething causes fever, irritability, feeding problems, drooling, biting, sleep disturbance, swollen gums, crying, lose of appetite for solids; and fever over 38oC was also believed to be associated with teething. The mean eruption time of the first tooth was from 6 months. Most caretakers had normal attitude to manifestations ascribed to teething (54.9%). The most common management to symptoms attributed to teething included increased breast-feeding, oral paracetamol, increased fluid supplying and physician consulting. Conclusion: Correct knowledge to teething in infants need to be educated for parents (caretakers) and even for health professionals. Key words: knowledge, attitude, practices, teething, infants.

CLINICAL CHARACTERISTICS OF THE CHRONIC DACRYOCYSTITIS AND THE SUCCESS RATE OF EXTERNAL DACRYOCYSTORHINOSTOMY

2015 ◽  
pp. 29-34
Author(s):  
Van Nam Phan ◽  
Ba Kien Tran
Keyword(s):  
Success Rate ◽  
Key Words ◽  
Clinical Characteristics ◽  
Lacrimal Duct ◽  
Interventional Study ◽  
Chronic Dacryocystitis ◽  
External Dacryocystorhinostomy ◽  
The Mean

Purpose: To determine the clinical characteristics of the chronic dacryocystitis and the success rate of external dacryocystorhinostomy. Methods: The retrospective, interventional study without comparing on 27 patients (32 eyes) of chronic dacryocystitis who underwent dacryocystorhinostomy (DCR) from 2010 to 2011. Results were evaluated with standards: epiphora, purelence, lacrimal duct irrigation. Results: Over period of 6 months, 27 patients including 25 (92.59%) female, 2 (7.41%) male. The mean age was 49.8 years (range, 22-79 years). All patients demonstrated epiphera (range, 3 months – 11 years). Dacryocystorhinostomy was performed unilaterally in 81.48%, bilateral 18.52%. Successrate was 90.06% overall. Conclusions: Although techniques in dacryocystorhinostomy of DUPUY-DUTEMPS is old, its result is mainstay of treatment for chronic dacryocystitis in Vietnam. Key words: Dupuy-Dutemps, chronic dacryocystitis

RESULTS OF INTRALESIONAL TRIAMCINOLONE ACETONIDE FOR CHALAZION TREATMENT

2011 ◽  
pp. 100-104
Author(s):  
Thi Thu Nguyen ◽  
Viet Hien Vo ◽  
Thi Em Do
Keyword(s):  
Success Rate ◽  
Key Words ◽  
Triamcinolone Acetonide ◽  
Lower Eyelid ◽  
Upper Eyelid ◽  
Interventional Trial ◽  
The Mean ◽  
First Time

The study use intralesional triamcinolone acetonide injection proceduce for chalazion treatment.1. Objectives: To evaluate results of intralesional triamcinolone acetonide injection for chalazion treatment. 2. Method: This noncomparative prospective interventional trial included 72 chalazions of 61 patients. 3. Results: 61 patients (72 chalazions) with 19 males (31.1%) và 42 females (68.9%), the mean age was 24 ± 9,78 years. 31.1% patients was the first time chalazion and 68.9% patients was more than one times chalazion including 78.6% patients was recurrent at the first position and 21.4% patients occur at new position. 72 chalazions with 16 (22.2%) chalazions was treated before and 56 (77.8%) chalazions wasn’t done that. 72 chalazions with 49 chalazions (68.1%) are local in upper eyelid and 23 chalazions (31.9%) are local in lower eyelid. The mean of chalazion diameter is 6.99 ± 3.03mm. Intralesional triamcinolone acetonide is injected to treat 72 chalazions with 16 (22.2%) chalazions are injected through the route of skin and 56 (77.8%) chalazions are injected through the route of conjunctiva. After 2 weeks follow-up, the success rate was 93.1% and 6.9% failed. 4. Conclusion: intralesional triamcinolone acetonide injection for chalazion treatment is really effective. Key words: chalazion, intralesional triamcinolone acetonide.

Design and development of manually operated gladiolus planter

2018 ◽  
Vol 5 (01) ◽  
Author(s):  
TAPAN K. KHURA ◽  
H. L. KUSHWAHA ◽  
SATISH D LANDE ◽  
PKSAHOO . ◽  
INDRA L . KUSHWAHA
Keyword(s):  
Coefficient Of Variation ◽  
Field Capacity ◽  
Power Source ◽  
Forward Speed ◽  
Cereal Crop ◽  
Maximum Coefficient ◽  
Coefficient Of Uniformity ◽  
The Mean ◽  
The Cost ◽  
Immense Potential

Floriculture is an age-old farming activity in India having immense potential for generating selfemployment and income to farmers. However, the cost of cultivation of flower is high as compared to cereal crop. Level of mechanization for different field operations is one but foremost reason for the higher cost of cultivation. As most of the Indian farmers are marginal and small, a need for manually operated gladiolus planter was felt. The geometric properties of gladiolus corm were determined for designing the seed metering system and seed hopper of the planter. The planter was evaluated in the field when pulled by two persons as a power source and guided by a person. The coefficient of variation and highest deviation from the mean spacing was observed as 12.93% and 2.65cm respectively. The maximum coefficient of uniformity of 90.59% was observed for a nominal corm spacing of 15cm at 0.56 kmh-1 forward speed. An average MISS percentage was observed as 2.65 and 2.25 for nominal corm spacing of 15 and 20 cm. The multiple index was zero for two levels corm spacing and forward speed of operation. The QFI was found in the range of 97.2 and 97.9 percent. The average field capacity of the planter was observed as 0.02 hah-1.The average draft requirement of the planter was found as 821 ± 50.3 N.

scholarly journals Technical note: Inherent benchmark or not? Comparing Nash–Sutcliffe and Kling–Gupta efficiency scores

2019 ◽  
Vol 23 (10) ◽  
pp. 4323-4331 ◽  
Author(s):  
Wouter J. M. Knoben ◽  
Jim E. Freer ◽  
Ross A. Woods
Keyword(s):  
Time Series ◽  
Coefficient Of Variation ◽  
Ad Hoc ◽  
Model Performance ◽  
Technical Note ◽  
Mean Flow ◽  
Model Adequacy ◽  
Robust Model ◽  
The Mean ◽  
Adequacy Assessment

Abstract. A traditional metric used in hydrology to summarize model performance is the Nash–Sutcliffe efficiency (NSE). Increasingly an alternative metric, the Kling–Gupta efficiency (KGE), is used instead. When NSE is used, NSE = 0 corresponds to using the mean flow as a benchmark predictor. The same reasoning is applied in various studies that use KGE as a metric: negative KGE values are viewed as bad model performance, and only positive values are seen as good model performance. Here we show that using the mean flow as a predictor does not result in KGE = 0, but instead KGE =1-√2≈-0.41. Thus, KGE values greater than −0.41 indicate that a model improves upon the mean flow benchmark – even if the model's KGE value is negative. NSE and KGE values cannot be directly compared, because their relationship is non-unique and depends in part on the coefficient of variation of the observed time series. Therefore, modellers who use the KGE metric should not let their understanding of NSE values guide them in interpreting KGE values and instead develop new understanding based on the constitutive parts of the KGE metric and the explicit use of benchmark values to compare KGE scores against. More generally, a strong case can be made for moving away from ad hoc use of aggregated efficiency metrics and towards a framework based on purpose-dependent evaluation metrics and benchmarks that allows for more robust model adequacy assessment.

scholarly journals Population density of helminths in ducks: effects of host’s age, sex, breed and season

1970 ◽  
Vol 6 (1) ◽  
pp. 45-51 ◽  
Author(s):  
T Farjana ◽  
KR Islam ◽  
MMH Mondal
Keyword(s):  
Population Density ◽  
Key Words ◽  
Parasitic Infection ◽  
Winter Season ◽  
Helminth Parasites ◽  
Domestic Ducks ◽  
The Mean

 A study was conducted to investigate the population density of helminth parasites in domestic ducks (Anas boschas domesticus) in relation to host's age, sex, breed and seasons of the year from March 2002 to May 2003. A total of 300 ducks were collected from different villages of Netrokona and Mymensingh districts of Bangladesh and autopsied to collect the parasites and counted to determine the population density of parasites. Off 300 ducks examined, 290 (96.66%) were infected with 17 species of helminth parasites in which 11 species were trematodes, 4 were cestodes and 2 nematodes. Among the parasites, density of cestodes was the highest (33.15±5.26), followed by trematodes (5.98±1.32); and nematodes (2.95±0.68). Mean density of parasites increased with the increase of age (young: 21.23±1.09, adult: 26.18±2.14 and old: 27.87±2.98) while the mean density of most of the helminth parasites was higher in female ducks (31.35±4.72) than in males (27.52±3.32). Indigenous ducks (33.72±3.61) were infected with the highest load of helminths than Khaki Campbell breed (29.61±4.32) of ducks. Mean density of most trematodes (5.42±0.80) were highest in winter season whereas mean density of all cestodes (48.43±4.85) and nematodes (4.13±1.76) were highest in summer.  The present study suggests that age, sex, breed of ducks and seasons of the year influence the parasitic infection to a greater extend. Key words: Population density, helminths, duck, Bangladesh DOI = 10.3329/bjvm.v6i1.1338 Bangl. J. Vet. Med. (2008). 6 (1): 45-51

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