Experimental and Numerical Analysis of Fracture in Prestressed Concrete

This work examines the crack initiation and propagation in Prestressed Concrete (PC) beams by a combined experimental and numerical approach. Four-point bending tests performed on PC sleepers lead to the formation of multiple cracks, in a number that depends on the specimen. The location of each fracture and its growth with time is monitored by Digital Image Correlation (DIC). The experiments are simulated by a finite element approach, reproducing the concrete response by a smeared crack model. The model parameters are calibrated to match the experimental moment deflection curve. In this study, only the beam segment enclosing one crack is discretized. The effect of the external load is simulated by applying the horizontal displacements returned by DIC at the vertical boundaries of the analyzed region. Thus, uncertainties are reduced since there is no need to discretize the PC element in its whole length, to include the supports and the loading plates, and to simulate the interactions between the different components

Hubungan Antara Kecerdasan Emosi Dengan Stres Kerja Pada Karyawan Perum Perhutani Salatiga

Setiap perusahaan menginginkan SDM yang memiliki daya tahan yang baik dengan manajemen stres sehingga tidak mengganggu kemampuan berfikir saat menjalankan tuntutan pekerjaan dan saat dihadapkan pada permasalahan pekerjaan. Namun pada kenyataanya tidak sedikit karyawan sering merasakan ketegangan dengan tuntutan kerja sehingga konsentrasi berkurang, dan menyebabkan stres kerja. Penelitian ini bertujuan untuk menguji hubungan antara kecerdasan emosi dengan stress kerja pada karyawan Perum Perhutani Salatiga. Subjek dalam penelitian ini adalah karyawan Perum Perhutani Salatiga, yang bekerja pada 4 seksi bagian, yaitu seksi pengukuran perpetaan & sarpra hutan, seksi perencanaan SDH, seksi PHL & SPPPU dan bagian sentral yang berjumlah 120 karyawan. Teknik pengambilan sampel dalam penelitian ini menggunakan purposive sampel. Adapun skala yang digunakan adalah skala kecerdasan emosi berdasarkan aspek yang dikemukakan oleh Goleman (2001) dan skala stress kerja mengacu pada aspek yang dikemukakan oleh Anoraga (1992). Teknik analisis data menggunakan korelasi product moment yang dibantu dengan menggunakan program SPSS 16 for Windows. Berdasarkan hasil perhitungan diperoleh nilai koefisien korelasi sebesar rxy = -0.531 dengan nilai sig. 0,000 (p<0,01). Hasil tersebut menunjukkan ada hubungan negatif yang sangat signifikan antara kecerdasan emosi dengan stres kerja. Semakin tinggi kecerdasan emosi maka semakin rendah stres kerja, begitu sebaliknya semakin rendah kecerdasan emosi maka semakin tinggi stres kerja. Sumbangan efektif sebesar 0,281 sehingga kecerdasan emosi berpengaruh terhadap stres kerja sebesar 28,1%, maka masih terdapat 71,9% pengaruh dari variabel lain seperti jenis kelamin, usia, tipe kepribadian, kondisi pekerjaan, faktor kepribadian dll. Hasil analisis diketahui variabel kecerdasan emosi pada subyek tergolong tinggi, hal ini ditujukkan dengan hasil rerata empirik (RE) sebesar 116,07 dengan rerata hipotetik (RH) sebesar 92,5. Sedangkamn variabel stres kerja menunjukkan hasil rerata empirik (RE) sebesar 102,53 dengan rerata hipotetik (RH) sebesar 120, yang artinya subjek memiliki tingkat stres kerja yang tergolong rendah

Application of AI in Chemical Engineering

A major shortcoming of traditional strategies is the fact that solving chemical engineering problems due to the highly nonlinear behavior of chemical processes is often impossible or very difficult. Today, artificial intelligence (AI) techniques are becoming useful due to simple implementation, easy designing, generality, robustness and flexibility. The AI includes various branches, namely, artificial neural network, fuzzy logic, genetic algorithm, expert systems and hybrid systems. They have been widely used in various applications of the chemical engineering field including modeling, process control, classification, fault detection and diagnosis. In this chapter, the capabilities of AI are investigated in various chemical engineering fields

An Efficient Architecture for Information Retrieval in P2P Context Using Hypergraph

Peer-to-peer (P2P) Data-sharing systems now generate a significant portion of Internet traffic. P2P systems have emerged as an accepted way to share enormous volumes of data. Needs for widely distributed information systems supporting virtual organizations have given rise to a new category of P2P systems called schema-based. In such systems each peer is a database management system in itself, ex-posing its own schema. In such a setting, the main objective is the efficient search across peer databases by processing each incoming query without overly consuming bandwidth. The usability of these systems depends on successful techniques to find and retrieve data; however, efficient and effective routing of content-based queries is an emerging problem in P2P networks. This work was attended as an attempt to motivate the use of mining algorithms in the P2P context may improve the significantly the efficiency of such methods. Our proposed method based respectively on combination of clustering with hypergraphs. We use ECCLAT to build approximate clustering and discovering meaningful clusters with slight overlapping. We use an algorithm MTMINER to extract all minimal transversals of a hypergraph (clusters) for query routing. The set of clusters improves the robustness in queries routing mechanism and scalability in P2P Network. We compare the performance of our method with the baseline one considering the queries routing problem. Our experimental results prove that our proposed methods generate impressive levels of performance and scalability with with respect to important criteria such as response time, precision and recall.Comment: 2o pages, 8 figure

Impact of particles tracking model of nanofluid on forced convection heat transfer within a wavy horizontal channel

Development of modern heat exchangers or solar collectors is related to the analysis of working fluid flow and heat transfer within different channels. The energy transport enhancement can be reached by including nanofluids as working media and irregular channels to intensify the heat removal. The present research is devoted to computational analysis of nanosuspension forced convection in a horizontal wavy channel under the impact of heating from the upper wavy surface. The single-phase nanofluid approach with experimentally-based correlations for viscosity and thermal conductivity holds implemented for an investigation in combination with Newton's second law for the description of the motion of the nanoparticle within the channel. The formulated boundary-value problem has been worked out by the finite element technique. Rules of Reynolds number, number of channel waviness, and dimensionless time on nanoliquid flow, energy transport and nanoparticles motion within the channel as well as average parameters. It has occurred that a rise from Reynolds number characterizes a narrowing of the fluid tube within the channel with an improvement of the average velocity and average Nusselt number. Augmentation of the channel waviness number results in an increment of the average particles velocity and average temperature

Bioefficacy of selected insecticides on late stage instars of bagworm, metisa plana (walker) / Mohammad Daniel Mat …[et al.]

Metisa plana is a significant oil palm pest in South East Asia and are well recognized for its devastating impact on oil palms in Malaysia. Due to the high intensity of the M. plana assault on oil palm plantation in the peninsular, Malaysia. The use of insecticides has become a famous means of controlling M. plana infestation when the economic threshold is reached. Three selected insecticides are Cypermethrin, Flubendiamide, and Bacillus thuringiensis tested for their toxicity toward M. plana. Late-stage instar of M. plana was collected at Felda Serting Hilir 4, Bahau, to be tested on three different pesticides, including one control treatment. For each treatment, five replications were exposed to the selected chemical by using the leaf dip bioassay method. The mortality of M. plana was recorded for eight consecutive days. Results showed that both Cypermethrin and Flubendiamide could achieve a 100% mortality rate within four days while it takes eight days for Bacillus thuringiensis and control treatment. Further study should be done in the field to obtain more accurate results when exposed to natural conditions and the environmen