PERSEPSI PETANI TERHADAP VARIETAS UNGGUL BARU INPARI 30 DAN 33 DI DESA TANJUNGSARI KECAMATAN BANYUDONO KABUPATEN BOYOLALI

This research aimed to analyze the farmers’ perception, to analyze the factors composing the farmers’ perception, to analyze the relationship between factors composing perception and the farmers’ perception on new superior cultivars of Inpari 30 and 33, and to analyze the difference of perception between the farmers using Inpari 30 and 33 new superior cultivars and those not using them. The fundamental research method employed was a descriptive qualitative with survey technique. The research location was determined purposively. The sample was taken using Quota Random Sampling, consisting of 60 respondents. Data analysis was carried out using Spearman’s rank and Mann Whitney’s U analyses. The result of research showed that there was a very significant relationship between non-formal education and farmers’ perception on Inpari 30 and 33 new superior cultivars, at significance level of 99%. Meanwhile, age, formal education, length of time becoming farmers, land width, and land ownership factors were not correlated significantly. There was a difference of perception between the farmers and those using Inpari 30 and 33 new superior cultivars.

Lateral Vibrations in Deep Hole Drilling Due to Land Width Variation

In drilling processes, self-excited vibrations have a negative influence on the achievable drilling qualities and tool life. Low-frequency radial vibrations are characterised by oscillating movements of the tool tip and the generation of lobed holes in drilling. This study focuses on the participation and influence of the land widths of twisted drilling tools on these vibrations. Therefore, drilling tools with different land widths and a length-to-diameter ratio of 12 are used, and different parameters, such as feed rate, cutting speed, coolant pressure, pre-hole diameter, and chuck selection, are varied in a drill-out process. The results show that the land widths have a statistically significant influence on the formation of lateral vibrations and the generation of lobed holes.

Effect of design parameters and operational conditions on the motion accuracy of hydrostatic thrust bearing

In this study, the effect of design parameters and operational conditions on motion accuracy of the closed configuration hydrostatic thrust bearing was researched. Key design parameters include land width, nominal oil film thickness, and perpendicularity error between mandrel and thrust plates. Oil supply pressure, external load, and rotation load are the considered operational conditions. Predictions of the induced effect are made by introducing oil film clearance function, governing equations, flow rate continuity equations, and dynamic equations of mandrel to model axial rotation error and angular motion error. The results show that the axial rotation accuracy increased, as land width (larger than 8 mm), nominal oil film thickness, and oil supply pressure increased, but there was little impact on angular motion error. The axial rotation error and angular motion error increased with the increase in the external load and rotation speed. Confirmation of the perpendicularity error has been achieved, in this study, by conducting experiments, using ultra-precision measuring machine. In addition, axial rotation error was tested on a hydrostatic rotary table and compared with the simulation results to check the validity of the proposed method. The results provide useful design guidelines and operation advice for hydrostatic thrust bearing in high-precision machine tools.

Fuzzy-DSM for Evaluating City-Forest Governance in Indonesia

City-forest is fruitful for human’s life and health, particularly for people who living in Metropolitan. A decision support model (DSM) was established academically to evaluate five city-forests in Indonesia. Fuzzy-logic was functioned as a main method and model was designed in Android based application for easy to use. Five parameters were functioned in the model, they are land width, land type, tree number, tree type, and maintenance quantity. The constructed model is able to measure the quality of city-forest governance for five forests in Indonesia as a sample of the study

CHARACTERISTICS OF ESTATE FARMERS AND CONTRIBUTION OF ESTATE COMMODITIES ON HOUSEHOLD INCOME IN NUSANIWE DISTRICT, AMBON CITY

Ambon as the capital of Maluku Province had been occupied by 3,558 farmers whose farming works have contributed to the production of estate commodities for about 1,169 tons. There were three estate commodities with significant contribution, namely clove, nutmeg, and coconut. The objective of research was to analyze the characteristics of estate farmers and the contribution of estate commodities on household income. Sample was determined purposively from Nusaniwe District, precisely 30 farmers from Nusaniwe Subdistrict, 60 farmers from Latuhalat Subdistrict, 50 farmers from Amahusu Subdistrict, and 60 farmers from Urimessing Subdistrict. Total sample was 200 farmers. Data were collected using questionnaire and depth interview with key informant. Data on respondent characteristic were analyzed through simple tabulation. Income count was used to analyze the contribution of each estate commodity on household income. Result of research showed that education, number of household member, side-job selection, land width, and commodity species were not varying across subdistricts. Contribution of clove and nutmeg to household income was found as high for 70 – 80 %, while that of coconut reached only 10 – 20%. Side-job activity as fisher and construction worker gave contribution to household income for 5 – 10%.

Experimental Studies of Effect of Land Width in PEM Fuel Cells with Serpentine Flow Field and Carbon Cloth

Flow field plays an important role in the performance of proton exchange membrane (PEM) fuel cells, such as transporting reactants and removing water products. Therefore, the performance of a PEM fuel cell can be improved by optimizing the flow field dimensions and designs. In this work, single serpentine flow fields with four different land widths are used in PEM fuel cells to study the effects of the land width. The gas diffusion layers are made of carbon cloth. Since different land widths may be most suitable for different reactant flow rates, three different inlet flow rates are studied for all the flow fields with four different land widths. The effects of land width and inlet flow rate on fuel cell performance are studied based on the polarization curves and power densities. Without considering the pumping power, the cell performance always increases with the decrease in the land width and the increase in the inlet flow rates. However, when taking into consideration the pumping power, the net power density reaches the maximum at different combinations of land widths and reactant flow rates at different cell potentials.

Vegetables Mapping using Production and Socio-economic Indicators Approach

Founded in 2007, Serang was considered as one of new cities in Indonesia. That was why, vegetables commodity mapping was not available yet. This mapping was essential for a new city to create an accurate policy in order to develop and maintain sustainable agriculture practices. Many agriculture commodities mapping were constructed by using Location Quotient (LQ) method. Unfortunately, they were based on productivity only. In this paper, we presented a vegetables commodity mapping by not only using production factor, but also farmer's socio-economic indicators, namely: (1) land width (preservation), (2) future land width (enhancement), and (3) household expenditure. Production factor and the farmer's socio-economic indicators were mapped and drawn in a biplot as the fist and the second layer. These two layers were overlayed in order to obtain district-commodity priority. Finally, this study resulted four district-commodity priority categories they are: First, Cipocok Jaya district as the main priority with cucumber as its potential commodity. Second, Curug district with chili as its commodity. Third, Walantaka distict with chili and Taktakan district with pea bean as their potential commodities, and finally, Kasemen and Serang district that has no identified commodity yet.

Analytical Model of Progression of Flank Wear Land Width in Drilling

In multipoint operations like drilling, cutting velocities and cutting-edge geometries vary along cutting lips so is the rate of progression of flank wear. Analytical evaluation of flank wear land width in the case of complex tools has received a limited attention so far. This work evaluates progression of flank wear in orthogonal machining and adopts it to drilling. An abrasive flank wear has been modeled, wherein, cutting speed determines the rate of abrasion, and the feed rate determines the chip load. The model considers stress distribution along rake surfaces, and temperature-dependent properties of tool and work materials. Assuming that the flank wear follows a typical wear progression as in a pin-on-disk test, the model evaluates cutting forces and the consequent abrasive wear rate for an orthogonal cutting. To adopt it to drilling, variation in cutting velocity and dynamic variation in rake, shear, and friction angles along the length of the cutting lips have been considered. Knowing the wear rate, the length of the worn-out flank (vb) has been evaluated. The model captures progression of flank wear in zones (i), (ii), and (iii) of a typical tool-life plot. It marginally underestimates the wear in the rapid wear region and marginally overestimates it in the steady-state region.