scholarly journals Maintainability of electronic instruments for meteorological applications

MAUSAM ◽  
2021 ◽  
Vol 43 (4) ◽  
pp. 349-352
Author(s):  
N. SEN ROY

The concept of Maintainability (M) of electronic instruments. though of recent origin, has Important application for meteorological equipments, which have special requirements. M is defined quantitatively in terms of mean time to repair and is Influenced by the failure behaviour of an equipment. An equipment goes through teething trouble, useful and terminal phase. Much of  maintainability can be incorporated during design and production phase. This reduces the effective overall cost of the equipment during its life time. Special maintenance support system is necessary for meteorological Instruments. Some recent tools for trouble shooting in digital systems have been discussed.

Author(s):  
عبدالفتاح سليمان المشاط وعبدالحميد محمد رجب وأحمد محمود خضرة عبدالفتاح سليمان المشاط وعبدالحميد محمد رجب وأحمد محمود خضرة

This paper proposes an effective decision support system based on an absorbing Markov model, which is used for helping decision makers in Faculty of Computing and Information Technology (FCIT) at King Abdul Aziz University (KAU) in controlling student’s flow transition enrollment. Several important controlling criteria that govern student’s flow performance during semesters are evaluated. These include estimating students flow between different study levels, the average life time a student spends at each level, the semesters required for graduation, and students graduating probability. A complete performance evaluation comparison between boys and girls at IT College is investigated. Results show that girls achieved better performance than boys. The system has several advantages, such as, helping to find any bottle necks to be solved during student’s transition study from one semester to another, and helping to know students needed facilities to planning for future required resources, hence achieving good quality and efficient university education. The proposed model is validated using cross-validation methodology, and the achieved results were acceptable


2018 ◽  
Vol 7 (3) ◽  
pp. 270-280
Author(s):  
Immawati Ainun Habibah ◽  
Tatik Widiharih ◽  
Suparti Suparti

Chronic Kidney Disease (CKD) is a failure of kidney function that which get slowly and can not recover. Most of the patients CKD get death sudden becuse of cardiovascular complications (related to the heart and blood vessels) however only minor part can reach terminal phase (CKD stage 5) which need replacement therapy of Kidney. Replacement therapy of Kidney are hemodialysis, peritoneal dialysis, and Kidney transplant. Because of that, the importance to study how long the patient opportunity is life endurance analysis.  Survival analysis methods to life depend from the life time and status of individual life time. Survival analysis uses Kaplan-Meier method. During the observation process, there is different observations so censor type III is choosen. Censor type III is censoring type which research is done to individual in and out for determine time, because of that estimation value of survival can be caunted using Kaplan Meier method with censor type III. This research uses medical records data from the patients with kidney failure period 1 January 2014 until 30 November 2017 in RSUD dr.R. Soedjati Soemodiarjo Purwodadi Grobogan Regency. The results of the analysis and discussion are known that if hemodialysis getting longer done, estimation value of survival. With an average estimate of survival is 776 days. Keywords: Chronic Kidney Disease, Survival Analysis, Kaplan Meier


2016 ◽  
Vol 10 (3) ◽  
pp. 211-218
Author(s):  
Hadi Sunandrio

Rod Hanger Tube Heater yang sudah beroperasi sekitar ± 7 bulan akan tetapibelum dilengkapi dengan best practice berapa lama MTBF (Mean Time BetweenFailure) atau Life Time nya. Oleh karena itu dibutuhkan pengujian untukmengetahui berapa sebenarnya Life Time dari Rod Hanger, yang nantinya akanmenjadi acuan MTBF dari Rod Hanger tersebut. Pada tulisan ini akan disajikansuatu hasil pengujian mulur (creep test) dari Rod Hanger, yang kemudiandiekstrapolasi sehingga akan menghasilkan grafik LMP vs tegangan, yangmerupakan kombinasi tiga parameter yaitu waktu (time to rupture), logaritmategangan dan suhu operasi menjadi satu kurva yang disebut Kurva MasterLarson-Miller Parameter (LMP Master Curve). Selanjutnya parameter ini dapatdigunakan untuk menghitung umur pakai Rod Hanger yang dioperasikan padasuhu tinggi, dengan menggunakan persamaan Larson-Miller Parameter (LMP)


Author(s):  
L. Y. Waghmode ◽  
A. D. Sahasrabudhe

The objective of this paper is to develop a methodology for effective implementation of life cycle costing (LCC) in design and procurement of repairable and non-repairable products. For this purpose, a generalized model for LCC of repairable and non-repairable products has been proposed. The equations of cost components of the proposed generalized model have been formulated for repairable systems based on the reliability and maintainability aspects to enable the life-time cost conscious design of such systems. The repairable systems typically have a life span of 10 to 20 years and experience multiple failures over their life span. The life cycle cost of a repairable system is significantly influenced by its reliability and maintainability. The life time energy and/or maintenance cost often dominate LCC for most of the repairable systems. Under the condition of constant failure rate the repairable system reliability is characterized by mean time between failures (MTBF) and maintainability by mean time to repair (MTTR). A higher value of MTBF and lower value of MTTR results into lower life cycle cost and therefore a due consideration to these factors is essential while designing repairable systems. The generalized LCC model presented in this paper will assist the designers to compare the life cycle cost of their different design alternatives at product design phase wherein most of the life cycle costs are committed. The developed generalized LCC model is applied to a typical repairable system, a pump from industry and the results obtained are presented.


Parasitology ◽  
1968 ◽  
Vol 58 (4) ◽  
pp. 801-817 ◽  
Author(s):  
Thomas R. Odhiambo

Glossina pallidipesAusten have been successfully reared in the adult stage in the laboratory. The flies fed readily on the belly of guinea-pigs, and the latter did not seem to be worried by the attentions of the flies.Immediately after adult emergence the flies were kept individually in tubes at four different temperatures (20°, 22°, 24° and 28 °C), at a relative humidity of 40 ± 5%, and they were offered guinea-pigs daily. Fifty per cent of the flies reared at temperatures of 20° and 28 °C died during the first 5 days, 50% of those reared at 24 °C died during the first 10 days, and 50% of those reared at 22 °C lived for more than 50 days.Few flies reared at 20° or 28 °C fed at all, and those that did had only four or five meals in their life-time; most of the flies reared at 22° or 24 °C did feed, but those reared at 24° took only a few meals. Most of these meals were ‘full’ ones, but a considerable proportion of meals taken by flies reared at 20 °C were ‘partial’ ones. The interval between meals was usually 3 or 4 days; but the time taken between adult emergence and time of first meal was shorter, except for the flies reared at 20 °C.When tsetse flies are reared at 22 °C the first six blood-meals are smaller than subsequent ones. The size of the meals and the rate of body growth do not seem to be related to the gonadotrophic cycles. On the other hand, the terminal phase of growth in both sexes shows a steady increase in body weight.The factors that might influence feeding, growth, and the longevity of adult tsetse flies are discussed.Thanks are extended to Mr J. M. B. Harley of the East African Trypanosomiasis Research Organization for sending me tsetse pupae, to Miss Caroline Walter and Mr John Boro for technical assistance, and to the Rockefeller Foundation for a research grant.


2018 ◽  
Vol 7 (2.19) ◽  
pp. 101
Author(s):  
Dharmateja M ◽  
Sriraman Kothuri ◽  
Kuna. Venkateswararao

Farmers have been facing issues while selling their food crops in market due to intermediate persons, who actually got profit by setting low price while buying from farmers and later sell the same at higher price to the customers. Through e-application is developed for farmers to set their own price to their products and allows buyers for e-auction. Farmers can set the initial bid amount based on quality, life time and current market price of the products before going for e-auction. The buyers can find nearest sellers through GPS navigation system. Choices locked once validity of bidding over and corresponding buyer, seller get notified through SMS. The interface also act as Decision Support System(DSS) for farmers to post their queries for getting advice's from agriculture specialists. 


2020 ◽  
Vol 6 (3) ◽  
pp. 31-35
Author(s):  
S.А. Efremof ◽  
◽  
E.А. Gruzdeva ◽  
V.V. Petkau ◽  
◽  
...  

Requirements to the modern information systems become more complicated. Nowadays it is not enough just to collect data and to ascertain the result. Work support system of the oncological service (WSSO) allows to prevent defects in patient diagnostic and treatment management in real time mode. Regional oncological information system ONCOR performs this role in Sverdlovsk region. ONCOR is a part of State information system. It aggregates data from different sources: medical organizations, primary oncology offices, healthcare department, compulsory health insurance fund, insurance companies etc. The results of WSSO introduction in Sverdlovsk region are presented in this issue. First it led to the shortening the term of routing the patients with malignant tumors from the first visit to the medical organization at the place of residence to the specialized organization. Mean time from the first visit of doctor till the referral to the regional oncology dispensary grew from 20 to 32 days as the electronic entry throughout ViPNet was introduced. It was reduced from 32 to 18 days thanks to WSSO. The time from referral till actual doctor’s appointment is under the responsibility of regional oncology center. WSSO allows to control this index, to reveal the problem key points and to affect them. This time was reduced from 14 to 5 days. The second part of the issue is devoted to the veracity of WSSO data which are controlled throughout the integration and coordination with different information systems. As an example, the dynamic of early detection of malignant tumors is presented. The share of I-II stages has changed from 53% to 57%.


Author(s):  
T. Koshikawa ◽  
Y. Fujii ◽  
E. Sugata ◽  
F. Kanematsu

The Cu-Be alloys are widely used as the electron multiplier dynodes after the adequate activation process. But the structures and compositions of the elements on the activated surfaces were not studied clearly. The Cu-Be alloys are heated in the oxygen atmosphere in the usual activation techniques. The activation conditions, e.g. temperature and O2 pressure, affect strongly the secondary electron yield and life time of dynodes.In the present paper, the activated Cu-Be dynode surfaces at each condition are investigated with Scanning Auger Microanalyzer (SAM) (primary beam diameter: 3μmϕ) and SEM. The commercial Cu-Be(2%) alloys were polished with Cr2O3 powder, rinsed in the distilled water and set in the vacuum furnance.Two typical activation condition, i.e. activation temperature 730°C and 810°C in 5x10-3 Torr O2 pressure were chosen since the formation mechanism of the BeO film on the Cu-Be alloys was guessed to be very different at each temperature from the results of the secondary electron emission measurements.


Author(s):  
K. Z. Botros ◽  
S. S. Sheinin

The main features of weak beam images of dislocations were first described by Cockayne et al. using calculations of intensity profiles based on the kinematical and two beam dynamical theories. The feature of weak beam images which is of particular interest in this investigation is that intensity profiles exhibit a sharp peak located at a position very close to the position of the dislocation in the crystal. This property of weak beam images of dislocations has an important application in the determination of stacking fault energy of crystals. This can easily be done since the separation of the partial dislocations bounding a stacking fault ribbon can be measured with high precision, assuming of course that the weak beam relationship between the positions of the image and the dislocation is valid. In order to carry out measurements such as these in practice the specimen must be tilted to "good" weak beam diffraction conditions, which implies utilizing high values of the deviation parameter Sg.


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