scholarly journals SISTEM PERHITUNGAN LAMA PENYINARAN MATAHARI DENGAN METODE OTSU THRESHOLD (STUDI KASUS: ST. KLIMATOLOGI BARONGAN)

Compiler ◽  
2016 ◽  
Vol 5 (2) ◽  
Author(s):  
Asih Pujiastuti ◽  
Agus Harjoko

Solar radiation measurements in climatology station barongan done by using campbell stokes and record card. Solar radiation is the accumulation of the whole length of the object radiation recorded on the record card. Solar radiation data reading performed by observers by estimating the long of object irradiation compared with the scale of hours listed on the record card. The difficulties encountered by observers in conducting solar radiation data readout is the shape of the object radiation recorded on the record card are not always in the form of elongated areas, some areas disjointed, even can only form small holes along the track on the card record. The purpose of this study was to design and build a system that can be used to calculate solar radiation recorded on the card record, thus increasing the accuracy of measurement data readout. Cropping process is carried out in order to obtain the right area for analysis. The approach method in object segmentation is done by implementing a solar radiation threshold otsu method. The test results showed that the determination o f the radius o f the opening and removing noise value appropriately irradiation can obtain the number o f objects on test images with RMSEof1.4429 compared with the amount o f exposure o f the image o f the original object. Results o f calculation solar radiation by the system showed system RMSE o f 0,51 to observer calculation.

2018 ◽  
Vol 52 ◽  
pp. 00045
Author(s):  
Sri Fajar Ayu ◽  
Destanul Aulia

Prior research by authors on the use of pesticides and their impact on 75 vegetable farmers in Simpang Empat subdistrict, Karo district, North Sumatra showed that 60% of respondents applied pesticides in excess of the packaging instructions. Respondents were also found not to use a complete protective device. Almost 70% of respondents have mild toxicity complaints, and based on blood cholinesterase levels are also found most respondents have mild toxicity. Pesticide residue test results also found 0.728 residues of chlorpyrifos and 0.321 profenofos in vegetables produced in this area. This led to continued review by checking the technical efficiency in the use of pesticides. The method used is a quantitative method with the Data Envelope Analysis (DEA) approach to analyze technical efficiency of pesticide on each commodity. The population is the whole vegetable farmer who grew tomatoes, Chinese cabbage and cauliflower at the time of the study. The entire population is used to be a sample of 35 tomato and cauliflower farmers and 20 Chinese cabbage farmers. The results of the study indicate that the uses of pesticide as production inputs on tomato commodities, Chinese cabbage and cauliflower are not technically efficient. It is suggested to farmers to use pesticide input according to the rules, proper dosage, on target, on time, the right way so that pesticide used is technically efficient.


1971 ◽  
Vol 93 (4) ◽  
pp. 1225-1228 ◽  
Author(s):  
W. L. Starkey ◽  
T. G. Foster ◽  
S. M. Marco

A new design parameter, friction-instability, is defined in this paper. Friction-instability is a variation in the coefficient of friction which may occur at any time during the life of a brake lining. A friction-index is defined which measures this variation. A lining which has a high friction index may tend to cause an automobile to swerve either to the right or to the left. A unique experimental facility is described by means of which the friction-instability characteristics of brake linings can be measured. Test results using this facility are presented and interpreted. The friction-index is proposed as a new parameter which should be taken into consideration when brakes are designed and, developed. This index should be particularly useful as a quality control device to insure that machines which use mass-produced braking systems will perform in a safe and effective manner.


2015 ◽  
Vol 741 ◽  
pp. 354-358 ◽  
Author(s):  
Yang Shan Tang ◽  
Dao Hua Xia ◽  
Gui Yang Zhang ◽  
Li Na Ge ◽  
Xin Yang Yan

For overcoming the shortage of Otsu method, proposed an improved Otsu threshold segmentation algorithm. On the basis of Otsu threshold segmentation algorithm, the gray level was divided into two classes according to the image segmentation, to determine the best threshold by comparing their center distance, so as to achieve peak line recognition under the condition of multiple gray levels. Then did experiments on image segmentation of the lane line with MATLAB by traditional Otsu threshold segmentation algorithm and the improved algorithm, the threshold of traditional Otsu threshold segmentation algorithm is 144 and the threshold of the improved Otsu threshold segmentation algorithm is 131, the processing time is within 0.453 s. Test results show that the white part markings appear more, the intersection place of white lines and the background is more clear, so this method can identify lane markings well and meet the real-time requirements.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Boluwaji M. Olomiyesan ◽  
Onyedi D. Oyedum

In this study, the performance of three global solar radiation models and the accuracy of global solar radiation data derived from three sources were compared. Twenty-two years (1984–2005) of surface meteorological data consisting of monthly mean daily sunshine duration, minimum and maximum temperatures, and global solar radiation collected from the Nigerian Meteorological (NIMET) Agency, Oshodi, Lagos, and the National Aeronautics Space Agency (NASA) for three locations in North-Western region of Nigeria were used. A new model incorporating Garcia model into Angstrom-Prescott model was proposed for estimating global radiation in Nigeria. The performances of the models used were determined by using mean bias error (MBE), mean percentage error (MPE), root mean square error (RMSE), and coefficient of determination (R2). Based on the statistical error indices, the proposed model was found to have the best accuracy with the least RMSE values (0.376 for Sokoto, 0.463 for Kaduna, and 0.449 for Kano) and highest coefficient of determination, R2 values of 0.922, 0.938, and 0.961 for Sokoto, Kano, and Kaduna, respectively. Also, the comparative study result indicates that the estimated global radiation from the proposed model has a better error range and fits the ground measured data better than the satellite-derived data.


Sign in / Sign up

Export Citation Format

Share Document