Studies were conducted on the effects of grain angle on reproducibility and accurate measurement of moisture content of four wood samples using a pin-style moisture meter. The wood samples were partitioned into four q...Studies were conducted on the effects of grain angle on reproducibility and accurate measurement of moisture content of four wood samples using a pin-style moisture meter. The wood samples were partitioned into four quadrants and moisture contents were measured along the grain direction in the first and second quadrants from 0 degree to 150 degrees insteps of 30 degrees. Experimental results indicated that the average moisture content remained constant as the grain angle increased. Repeated measurements of moisture content at different grain angles or points on the wood surface showed similar patterns of variation. Within-point standard deviations of the moisture contents were greater than between-point standard deviations. A non-destructive method of measuring moisture content at the same location or point on the wood surfaces could not be proposed because of the high variation of moisture content when repeated measurements were taken at the same point. Instead, accurate measurements of moisture content could be obtained at random positions within a radius of 30 mm from the point of intersection of the moisture content axis and the grain angle.展开更多
Coffee cultivation on dry area lately faces more often drought condition because of global warming effect. One effort to solve the problem is by using tolerant clones or varieties as the rootstocks. The aim of this re...Coffee cultivation on dry area lately faces more often drought condition because of global warming effect. One effort to solve the problem is by using tolerant clones or varieties as the rootstocks. The aim of this research is to observe influence of BP 308, BP 409, and Exelsa as rootstocks, on growth, yield and bean quality of BP 409, BP 534, BP 936 and BP 939 clones as scions. The research was conducted in Temanggung district of Central Java, Indonesia, using randomized complete block design with 5 replications 10 plants per replication. The result showed that rootstock influenced stem height and number of branches, leaf relative water content (RWC) during dry season, but not stem diameter. BP 308 and BP 409 rootstocks supplied water more than Exelsa, it seem RWC scion on both rootstocks were higher (82.0%) than that of Exelsa (80.0%). Exelsa rootstock cause scion grow more slowly, so bean yield was lower than on BP 308 and BP 409. Yield accumulation until 4 years old on Exelsa was 55% to BP 308, and 52.2% to BP 409 rootstock. Yield of BP 939/BP 308 and BP 409/BP 409 (scion/rootstock) tend to the highest. Rootstocks did not influence percentage of normal and abnormal beans and the outturns. Bean outturn was more influenced by clones. Exelsa rootstock improves caffeine content, body, astringent and bitterness characters of scion cherries, but decreases fragrance and aroma characters of scion yield. It is concluded that farther taxonomical relationship of rootstock, their influence on scion growth, yield and cup test characters are stronger.展开更多
This research objective is to propose a co-valorization of powdered tuff, containing a slight amount of clay and dune sand, by mixing the two substances at different rates such as 0%, 5%, 15%, 25% and 35% of sand. The...This research objective is to propose a co-valorization of powdered tuff, containing a slight amount of clay and dune sand, by mixing the two substances at different rates such as 0%, 5%, 15%, 25% and 35% of sand. The adapted criteria formulas are those recommended by the technical Saharan road. The results of the proposed study showed that "tuff-sand" mixtures are denser with a lower optimum water content modified proctor, the fine rate decreases together with the plasticity index, whereas the bearing index (CBR: California bearing ratio test) increases. The intrinsic characteristics, cohesion and sensitivity of mixtures with respect to compactness are almost identical to those oftuffwithout addition. The optimal adapted sand incorporation rate is estimated at 25% at 96% of compactness. Under these conditions, the amount of fines decreases from 40% to an acceptable level of 25% and the plasticity index from 16.2 to 12. The compaction water content decreases by 36% and the CBR (bearing index) increases by 30% and the compressive strength and sensitivity, according to compactness, of the elaborated material are almost identical to those oftuffwithout addition.展开更多
In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing Cr2O3 nanoparticles have be...In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing Cr2O3 nanoparticles have been developed at different ages of curing. For purpose of building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models are arranged in a format of 8 input parameters that cover the cement content, nanoparticle content, aggregate type, water content, the amount of superplasticizer, the type of curing medium, age of curing and number of testing try. According to these input parameters, in the neural networks and genetic programming models the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that every two models have strong potential for predicting the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles. It has been found that NN and GEP models will be valid within the ranges of variables. In neural networks model, as the training and testing ended when minimum error norm of network was gained, the best results were obtained and in genetic programming model, when 4 genes were selected to construct the model, the best results were acquired. Although neural network has predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.展开更多
文摘Studies were conducted on the effects of grain angle on reproducibility and accurate measurement of moisture content of four wood samples using a pin-style moisture meter. The wood samples were partitioned into four quadrants and moisture contents were measured along the grain direction in the first and second quadrants from 0 degree to 150 degrees insteps of 30 degrees. Experimental results indicated that the average moisture content remained constant as the grain angle increased. Repeated measurements of moisture content at different grain angles or points on the wood surface showed similar patterns of variation. Within-point standard deviations of the moisture contents were greater than between-point standard deviations. A non-destructive method of measuring moisture content at the same location or point on the wood surfaces could not be proposed because of the high variation of moisture content when repeated measurements were taken at the same point. Instead, accurate measurements of moisture content could be obtained at random positions within a radius of 30 mm from the point of intersection of the moisture content axis and the grain angle.
文摘Coffee cultivation on dry area lately faces more often drought condition because of global warming effect. One effort to solve the problem is by using tolerant clones or varieties as the rootstocks. The aim of this research is to observe influence of BP 308, BP 409, and Exelsa as rootstocks, on growth, yield and bean quality of BP 409, BP 534, BP 936 and BP 939 clones as scions. The research was conducted in Temanggung district of Central Java, Indonesia, using randomized complete block design with 5 replications 10 plants per replication. The result showed that rootstock influenced stem height and number of branches, leaf relative water content (RWC) during dry season, but not stem diameter. BP 308 and BP 409 rootstocks supplied water more than Exelsa, it seem RWC scion on both rootstocks were higher (82.0%) than that of Exelsa (80.0%). Exelsa rootstock cause scion grow more slowly, so bean yield was lower than on BP 308 and BP 409. Yield accumulation until 4 years old on Exelsa was 55% to BP 308, and 52.2% to BP 409 rootstock. Yield of BP 939/BP 308 and BP 409/BP 409 (scion/rootstock) tend to the highest. Rootstocks did not influence percentage of normal and abnormal beans and the outturns. Bean outturn was more influenced by clones. Exelsa rootstock improves caffeine content, body, astringent and bitterness characters of scion cherries, but decreases fragrance and aroma characters of scion yield. It is concluded that farther taxonomical relationship of rootstock, their influence on scion growth, yield and cup test characters are stronger.
文摘This research objective is to propose a co-valorization of powdered tuff, containing a slight amount of clay and dune sand, by mixing the two substances at different rates such as 0%, 5%, 15%, 25% and 35% of sand. The adapted criteria formulas are those recommended by the technical Saharan road. The results of the proposed study showed that "tuff-sand" mixtures are denser with a lower optimum water content modified proctor, the fine rate decreases together with the plasticity index, whereas the bearing index (CBR: California bearing ratio test) increases. The intrinsic characteristics, cohesion and sensitivity of mixtures with respect to compactness are almost identical to those oftuffwithout addition. The optimal adapted sand incorporation rate is estimated at 25% at 96% of compactness. Under these conditions, the amount of fines decreases from 40% to an acceptable level of 25% and the plasticity index from 16.2 to 12. The compaction water content decreases by 36% and the CBR (bearing index) increases by 30% and the compressive strength and sensitivity, according to compactness, of the elaborated material are almost identical to those oftuffwithout addition.
文摘In the present paper, two models based on artificial neural networks and genetic programming for predicting split tensile strength and percentage of water absorption of concretes containing Cr2O3 nanoparticles have been developed at different ages of curing. For purpose of building these models, training and testing using experimental results for 144 specimens produced with 16 different mixture proportions were conducted. The data used in the multilayer feed forward neural networks models and input variables of genetic programming models are arranged in a format of 8 input parameters that cover the cement content, nanoparticle content, aggregate type, water content, the amount of superplasticizer, the type of curing medium, age of curing and number of testing try. According to these input parameters, in the neural networks and genetic programming models the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles were predicted. The training and testing results in the neural network and genetic programming models have shown that every two models have strong potential for predicting the split tensile strength and percentage of water absorption values of concretes containing Cr2O3 nanoparticles. It has been found that NN and GEP models will be valid within the ranges of variables. In neural networks model, as the training and testing ended when minimum error norm of network was gained, the best results were obtained and in genetic programming model, when 4 genes were selected to construct the model, the best results were acquired. Although neural network has predicted better results, genetic programming is able to predict reasonable values with a simpler method rather than neural network.