At present, the smartphone is equipped with several sensors such as Accelerometer, Gravity sensor, and Gyroscope which can be used to recognize human physical activities such as walking upstair and walking downstairs ...
At present, the smartphone is equipped with several sensors such as Accelerometer, Gravity sensor, and Gyroscope which can be used to recognize human physical activities such as walking upstair and walking downstairs etc. Machine learning is needed to group data and get information. Statistical methods have poor performance in classifying because procedures must be met. To overcome this, an ensemble technique was used. This study proposes the application of the gradientboost ensemble method to classify walking upstair and walking downstairs. The *** system is designed for data retrieval using a smartphone. Then, the dataset will be partitioned into 70% training data and 30% test data. The results show that the performance of the ensemble boosting method produces 81.82% accuracy, 86.11% sensitivity and 77.50% specificity.
We present some improvements on interpolation based control (IC) for linear discrete-time systems with polyhedral constraints on the control and the states variables. The plant may be uncertain, time-varying, and subj...
详细信息
The implementation of monitoring system in the facial acupressure learning media could increase the students’ proficiency. However the common learning media still has not implemented a monitoring system in their lear...
The implementation of monitoring system in the facial acupressure learning media could increase the students’ proficiency. However the common learning media still has not implemented a monitoring system in their learning process. This research was conducted to implement monitoring system in the mannequin head prototype as a learning media of facial acupressure using Bluetooth, wireless and Ethernet. The results of the implementation of monitoring system in the prototype showed that there were differences in the delay time between Bluetooth and wireless or Ethernet. The results data showed no difference in the average delay time between the use of Bluetooth with wireless and the use of Bluetooth with Ethernet in monitoring system of facial acupressure learning media. From all the facial acupressure points, the forehead facial acupressure point has the longest delay time of 11.93 seconds. The average delay time in all 3 class rooms was 1.96 seconds therefore the use of Bluetooth, wireless and Ethernet is highly recommended in the monitoring system of facial acupressure.
In this paper, an aerodynamic design of a single stage gas generator axial turbine for small turbojet engine is explained. As per design requirement, the turbine should be able to deliver power output of 155 kW at 0.8...
In this paper, an aerodynamic design of a single stage gas generator axial turbine for small turbojet engine is explained. As per design requirement, the turbine should be able to deliver power output of 155 kW at 0.8139 kg/s gas mass flow, inlet total temperature of 1200 K and inlet total pressure of 335330 Pa. The design phase consist of several steps, i.e.: determination of velocity triangles in 2D plane, 2D blading design and 3D flow analysis at design point using Computational Fluid Dynamics method. In the determination of velocity triangles, two conditions are applied: zero inlet swirl (i.e. the gas flow enter the turbine at axial direction) and constant nozzle angle design (i.e. the inlet and outlet angle of the nozzle blade are constant from root to tip). The 2D approach in cascade plane is used to specify airfoil type at root, mean and tip of the blade based on inlet and outlet flow conditions. The 3D approach is done by simulating the turbine in full configuration to evaluate the overall performance of the turbine. The observed parameters including axial gap, stagger angle, and tip clearance affect its output power. Based on analysis results, axial gap and stagger angle are positively correlated with output power up to a certain point at which the power decreases. Tip clearance, however, gives inversely correlation with output power.
Like other big cities in Indonesia, Semarang City as the capital of Central Java Province also has various city problems, one of them is the transportation problem. Transportation problems arise due to increased mobil...
Like other big cities in Indonesia, Semarang City as the capital of Central Java Province also has various city problems, one of them is the transportation problem. Transportation problems arise due to increased mobility of society that is not in balanced with the public transportation facilities and infrastructure availability. In order to create a better transportation system, the local government of Semarang City held Trans Semarang bus rapid transit (BRT) which began operating in 2010. This study aims to analyze the feasibility of BRT Trans Semarang corridor VI shelters. This research uses descriptive critique technique. The results are expected to be considered in determining the right policy in creating a better transportation system. Based on observations made, the majority of BRT Trans Semarang corridor VI uses non-permanent shelters and is less feasible to be a BRT shelter. Thus, the local government is expected to improve the feasibility of BRT Trans Semarang shelter so that the sense of security and comfort can be obtained by users of BRT. In addition, the local government is also expected to maintain the quality of services provided. These services include ticket service, the condition of buses, speed and waiting time, as well as the placement and condition of shelters.
Development of Conservation Batik concept becomes critical due to the recessive of traditional batik as the intangible cultural heritage of humanity. The existence of printed batik, polluting process, and new stream d...
Development of Conservation Batik concept becomes critical due to the recessive of traditional batik as the intangible cultural heritage of humanity. The existence of printed batik, polluting process, and new stream design becomes the consequences of batik industry transformation to creative industry. Conservation Batik was proposed to answer all the threats to traditional batik, in the aspect of technique, process, and motif. However, creativities are also critical to meet consumer satisfaction. Research and development was conducted, start with the initial research in formulating the concept, and exploration of ideas to develop the designs of conservation motifs. In development steps, cyclical process to complete motif with high preferences, in the aspect of aesthetics, productivity, and efficiency. Data were collected through bibliography, documentation, observation, and interview, and analyzed in qualitative methods. The concept of Conservation Batik adopted from the principles of Universitas Negeri Semarang (UNNES) vision, as well as theoretical analyses, and expert judgment. Conservation Batik are assessed from three aspect, design, process, and consumer preferences. Conservation means the effort of safeguarding, promoting, maintaining, and preserving. Concervation Batik concept could be interpreted as batik with: (1) traditional values and authenticity; (2) the values of philosophycal meanings; (3) eco-friendly process with minimum waste; (4) conservation as idea resources of design; and (5) raising up of classic motifs.
As phenolic polymer compound, the hydroxyphenolic groups in lignin enable it to act as antioxidant. In this study, organosolv and commercial lignin were tested for their activity as antioxidant in biodiesel. Organosol...
As phenolic polymer compound, the hydroxyphenolic groups in lignin enable it to act as antioxidant. In this study, organosolv and commercial lignin were tested for their activity as antioxidant in biodiesel. Organosolv lignin was obtained by first performing pretreatment of Oil Palm Empty Fruit Bunch (OPEFB) by organosolv method at 170 °C for 2.5 hours followed with isolation by use of H2SO4 20%. The organosolv and commercial lignin were added separately to biodiesel with concentration variation of 500, 1000, and 1500 ppm. Synthetic antioxidant butylated hydroxytoluene (BHT) was used as positive control in this study. Biodiesel oxidation stability test was performed by Rancimat method. Antioxidant activity tests were done by determining the acid value, peroxide value, and kinematic viscosity of biodiesel each week for 4 weeks. The yield and lignin content of organosolv lignin obtained from this study were 13,7% and 64.5% respectively. Hydroxyphenolic content of organosolv lignin by means of spectroscopy method showed value of 6.8%. Addition of organosolv lignin, commercial lignin, or BHT showed ability to inhibit the oxidation rate of biodiesel with the sequence of antioxidant activity from the largest to the smallest are successively BHT, commercial lignin, and organosolv lignin. Rancimat test showed that 1500 ppm organosolv lignin resulted 4.2 minutes biodiesel induction time which equals the result of 1000 ppm commercial lignin as well as 500 ppm BHT. This study reveals that organosolv lignin from OPEFB and commercial lignin have future potential to be utilized as natural antioxidant for biodiesel.
The Qushi’ang granodiorite(QSG) is located at the central east of the ophiolitic melange belt in the East Kunlun Orogenic Belt(EKOB) in the northern margin of the Qinghai-Tibetan Plateau. LA-MC-ICP-MS zircon U–P...
详细信息
The Qushi’ang granodiorite(QSG) is located at the central east of the ophiolitic melange belt in the East Kunlun Orogenic Belt(EKOB) in the northern margin of the Qinghai-Tibetan Plateau. LA-MC-ICP-MS zircon U–Pb dating suggests that the granodiorite and mafic microgranular enclaves(MMEs) crystallized 246.61±0.62 and 245.45±0.9 Ma ago, respectively. Granodiorite, porphyritic diorite, and MMEs are metaluminous and medium-K calk-alkaline series, with island-arc magma features, such as LILE enrichment and HFSE depletion. The porphyritic diorite has high Cr(13.50 ppm to 59.01 ppm), Ni(228.53 ppm to 261.29 ppm), and Mg~#(46–54). Granodiorite and porphyritic diorite have similar mineral compositions and evolved major and trace elements contents, particularly Cr and Ni, both of which are significantly higher than that in granites of the same period. The crystallization age of MMEs is close to that of granodiorite, and their major and trace elements contents are in-between porphyritic diorite and granodiorite. The results suggest that the original mafic magma, which was the product of mantle melting by subduction process, intruded into the lower crust(Kuhai Rock Group), resulting in the formation of granodiorite. Countinous intrusion of mafic magma into the unconsolidated granodiorite formed MMEs and porphyritic diorite. The granodiorite reformed by late-stage strike-slip faulting tectonic event indicates that the strike-slip fault of Middle Kunlun and the collision of the Bayanhar block with East Kunlun were later than 246 Ma. Therefore, the formation of the QSG not only indicates the critical period of evolution of East Kunlun but also represents the tectonic transition from oceanic crust subduction to slab breaking.
Cabe Jawa (Piper retrofractum Vahl) is an important commodity for herbal industries in Indonesia. One of the bioactive compounds in this herb is piperine. In this study, concentration of piperine in Cabe Jawa was anal...
Cabe Jawa (Piper retrofractum Vahl) is an important commodity for herbal industries in Indonesia. One of the bioactive compounds in this herb is piperine. In this study, concentration of piperine in Cabe Jawa was analysed using HPLC and UV spectrophotometry methods. Cabe Jawa samples were prepared using two different methods. The first sample (S1) was dried from fresh Piper retrofractum, while the second sample (S2) was dried from boiled Piper retrofractum. Both samples were extracted using Soxhlet, followed by solvent evaporation to obtain the concentrated extract. Piperine concentration was measured using UV spectrophotometry and HPLC via internal standard method. The yields of extract of S1 and S2 were 23.0% and 22.1%, respectively. Piperine UV spectrophotometry standard curve equation was y = 0.1107*(X)-0.1578, R2 = 0.9999, whereas HPLC standard curve equation was y = 105916*(X) + 28100.9, R2 = 0.9978. Piperine concentration in S1 and S2 extracts quantified using UV spectrophotometry were 19.0% and 18.1%., respectively. The values for S were much higher compared to values obtained by HPLC, which were 6.8% (S1) and 7.3% (S2). Therefore, the use of UV spectrophotometry for analysis of piperine is not recommended due to the interference of other compounds, which are absorbed at the same wavelength.
This was the study and designing of the thermoelectric block floor for power generator that are normally used for footpaths, traffic islands, and gardening together with solar radiation heat. Physically, this thermoel...
This was the study and designing of the thermoelectric block floor for power generator that are normally used for footpaths, traffic islands, and gardening together with solar radiation heat. Physically, this thermoelectric block is an octagonal block with a size of 19.8 × 19.8 × 6 cm. The block was composed of two layers. The upper layer received the solar radiation and produced the thermoelectric module heat by synthesizing thermoelectric materials and creating 4 thermoelectric modules from Bi2Te3 for one composition set where an aluminum sheet was used for cooling. Additionally, the lower layer was exposed to the ground with low temperature to produce the usable electric power. The efficiency of this electric power was tested with the solar radiation heat of the thermoelectric block floor and by the Thai Industrial Standards (TIS) 827-2531: Interlocking Concrete Paving Blocks. After installing the thermoelectric block floor at the faculty of Industrial Technology, Sakon Nakhon Rajabhat University, it was found that the block was usable as defined by TIS 827-2531: Interlocking Concrete Paving Blocks; meanwhile, the test on the electric power of the thermoelectric block floor indicated that the maximum electric potential difference was 73.91 mV where the temperature difference was 6.2 K measured from the surface of the block. In addition, the maximum electric power was 88.25 mV where the solar radiation was 1124.5 W m-2. Notably, this electric power of the thermoelectric block floor was directly variable following the solar radiation value. However, if used for power generator or as an alternative energy for engineering activities, the thermoelectric block should be properly designed and developed to produce higher level of electric power and more of them should be created for both series circuit and parallel circuit.
暂无评论