A framework for design engineering education in a global context

This paper presents a framework for teaching design engineering in a global context using innovative technologies to enable distributed teams to work together effectively across international and cultural boundaries. The DIDET Framework represents the findings of a 5-year project conducted by the University of Strathclyde, Stanford University and Olin College which enhanced student learning opportunities by enabling them to partake in global, team based design engineering projects, directly experiencing different cultural contexts and accessing a variety of digital information sources via a range of innovative technology. The use of innovative technology enabled the formalization of design knowledge within international student teams as did the methods that were developed for students to store, share and reuse information. Coaching methods were used by teaching staff to support distributed teams and evaluation work on relevant classes was carried out regularly to allow ongoing improvement of learning and teaching and show improvements in student learning. Major findings of the 5 year project include the requirement to overcome technological, pedagogical and cultural issues for successful eLearning implementations. The DIDET Framework encapsulates all the conclusions relating to design engineering in a global context. Each of the principles for effective distributed design learning is shown along with relevant findings and suggested metrics. The findings detailed in the paper were reached through a series of interventions in design engineering education at the collaborating institutions. Evaluation was carried out on an ongoing basis and fed back into project development, both on the pedagogical and the technological approaches

Adaptive saccade controller inspired by the primates' cerebellum

Saccades are fast eye movements that allow humans and robots to bring the visual target in the center of the visual field. Saccades are open loop with respect to the vision system, thus their execution require a precise knowledge of the internal model of the oculomotor system. In this work, we modeled the saccade control, taking inspiration from the recurrent loops between the cerebellum and the brainstem. In this model, the brainstem acts as a fixed-inverse model of the oculomotor system, while the cerebellum acts as an adaptive element that learns the internal model of the oculomotor system. The adaptive filter is implemented using a state-of-the-art neural network, called I-SSGPR. The proposed approach, namely recurrent architecture, was validated through experiments performed both in simulation and on an antropomorphic robotic head. Moreover, we compared the recurrent architecture with another model of the cerebellum, the feedback error learning. Achieved results show that the recurrent architecture outperforms the feedback error learning in terms of accuracy and insensitivity to the choice of the feedback controller

Efektifitas Ekstrak Biji Sirsak (Annona Muricata L) Sebagai Insektisida Alami Terhadap Nyamuk Aedes Aegypti Sebagai Vektor Dbd

Penyakit akibat virus dengue seperti Demam Dengue (DD) dan Demam Berdarah Dengue (DBD) adalahpenyakit yang dihasilkan oleh penularan vektor nyamuk dan merupakan mosquito-borne diseases terbesar didunia terutama pada negara tropis dan negara berkembang. Salah satu program pemberantasan vektor DBDadalah dengan menggunakan insektisida. Cara pengendalian alamiah yang dapat dilakukan adalah menggunakanbioinsektisida atau insektisida hayati yang merupakan suatu insektisida berbahan dasar yang berasal daritumbuhan dan mengandung bahan kimia (bioaktif) yang toksik terhadap serangga tetapi mudah terurai(biodegradable) di alam, sehingga tidak mencemari lingkungan, relatif aman dan bersifat selektif. Familitumbuhan yang dianggap merupakan sumber potensial insektisida nabati adalah Annonaceae. Penelitian inibertujuan untuk mengetahui efektifitas ekstrak biji sirsak (Annona muricata L) sebagai insektisida terhadapnyamuk Aedes aegypti. Jenis penelitian yang digunakan pada penelitian ini adalah eksperimen semu dengandesain post test only control group design. Sampel dalam penelitian ini adalah nyamuk Aedes aegypti sebanyak 10ekor pada masing-masing 4 unit perlakuan dan 1 kontrol dengan 4 kali pengulangan. Hasil penelitian inimenunjukan bahwa konsentrasi 15%, 30%, 45%, dan 60% yang menyebabkan jumlah nyamuk mati berturut-turut12.5%, 37.5%, 67.5% hingga pada konsentrasi maksimal 60% jumlah nyamuk mati rata-rata mencapai 97.5%.Berdasarkan uji probit nilai LC50 dan LC90 berturut-turut adalah 35.2132% dan 54.7572%. Hasil uji One AwayANOVA menunjukan bahwa nilai p<0,05 sehingga dapat disimpulkan terdapat perbedaan bermakna pada jumlahnyamuk yang mati antar kelompok yang dibandingkan

Role of Non-Selective Beta Blockers in Hepatocellular Carcinoma: An Analysis in Patients with Cirrhosis and Portal Hypertension

There are many different biochemical processes responsible for the hepatocelluar carcinoma (HCC) development that can be targeted for the prevention or halt progression of the HCC. Non-selective betablockers (NSBB) affects a multitude of intracellular biochemical and signaling pathways involved in carcinogenesis. Aim: To determine if NSBB may be protective for HCC in patients with cirrhosis and portal hypertension. Methods: We retrospectively enrolled 200 patients from medical records diagnosed with cirrhosis and portal hypertension between January 2001 and December 2013. Eighteen patients were excluded (taking selective beta-blocker and/or unavailable medical records). The etiology of cirrhosis, use of NSBB, demographics and the presence of HCC was collected. Result: There were 140 males and 42 females. The mean age for portal hypertension with cirrhosis without HCC was 53.5 ± 11.4 & with HCC was 62.2 ± 9.5 years. Univariate analysis of the association of NSBB with HCC yielded OR = 0. 11 (95% CI: 0.04 to 0.25); p \u3c 0.0001, suggesting a protective effect of NSBB. Multivariable analysis suggests virtually no change when the Odds ratio (OR) was adjusted for diabetes mellitus (DM), alcohol use, Hepatitis B virus (HBV) status, Black race and age ≥ 53. There was a slight increase in the OR adjusted for statin use. Conclusion: This study highlights association of NSBB use in the patients with liver cirrhosis and portal hypertension for prevention of HCC

New Singular and Nonsingular Colliding Wave Solutions in Einstein - Maxwell - Scalar Theory

A technique is given to generate coupled scalar field solutions in colliding Einstein - Maxwell (EM) waves. By employing the Bell - Szekeres solution as seed and depending on the chosen scalar field it is possible to construct nonsingular solutions. If the original EM solution is already singular addition of scalar fields does not make the physics any better. In particular, scalar field solution that is transformable to spherical symmetry is plagued with singularities.Comment: 15 pages, To be published in GR

Integrable Systems in Stringy Gravity

Static axisymmetric Einstein-Maxwell-Dilaton and stationary axisymmetric Einstein-Maxwell-Dilaton-Axion (EMDA) theories in four space-time dimensions are shown to be integrable by means of the inverse scattering transform method. The proof is based on the coset-space representation of the 4-dim theory in a space-time admitting a Killing vector field. Hidden symmetry group of the four-dimensional EMDA theory, unifying T and S string dualities, is shown to be Sp(2, R) acting transitively on the coset Sp(2, R)/U(2). In the case of two-parameter Abelian space-time isometry group, the hidden symmetry is the corresponding infinite-dimensional group of the Geroch-Kinnersley-Chitre type.Comment: 8 pages, LATEX, MSU-DTP-94/21, October 9

On the absence of scalar hair for charged rotating blackholes in non minimally coupled theories

In this work we check the validity of the no scalar hair theorem in charged axisymmetric stationary black holes for a wide class of scalar tensor theories.Comment: Revtex style, 11 pages, major rivisions done, appendix added, title change

Ehlers-Harrison transformations and black holes in Dilaton-Axion Gravity with multiple vector fields

Dilaton-axion gravity with $p U(1)$ vector fields is studied on space-times admitting a timelike Killing vector field. Three-dimensional sigma-model is derived in terms of K\"ahler geometry, and holomorphic representation of the SO(2,2+p) global symmetry is constructed. A general static black hole solution depending on $2p+5$ parameters is obtained via SO(2,2+p) covariantization of the Schwarzschild solution. The metric in the curvature coordinates looks as the variable mass Reissner-Nordstr\"om one and generically possesses two horizons. The inner horizon is pushed to the singularity if electric and magnetic SO(p) charge vectors are parallel. For non-parallel charges the inner horizon has a finite area except for an extremal limit when this property is preserved only for orthogonal charges. Extremal dyon configurations with orthogonal charges have finite horizon radii continuously varying from zero to the ADM mass. New general solution is endowed with a NUT parameter, asymptotic values of dilaton and axion, and a gauge parameter which can be used to ascribe any given value to one of scalar charges.Comment: 37 pages, Late

A hierarchical system for a distributed representation of the peripersonal space of a humanoid robot

Reaching a target object in an unknown and unstructured environment is easily performed by human beings. However, designing a humanoid robot that executes the same task requires the implementation of complex abilities, such as identifying the target in the visual field, estimating its spatial location, and precisely driving the motors of the arm to reach it. While research usually tackles the development of such abilities singularly, in this work we integrate a number of computational models into a unified framework, and demonstrate in a humanoid torso the feasibility of an integrated working representation of its peripersonal space. To achieve this goal, we propose a cognitive architecture that connects several models inspired by neural circuits of the visual, frontal and posterior parietal cortices of the brain. The outcome of the integration process is a system that allows the robot to create its internal model and its representation of the surrounding space by interacting with the environment directly, through a mutual adaptation of perception and action. The robot is eventually capable of executing a set of tasks, such as recognizing, gazing and reaching target objects, which can work separately or cooperate for supporting more structured and effective behaviors