Optimization and synthesis of a cam-linkage mechanism with a swing follower with variable pivot

In this paper, a cam-linkage mechanism with a swing follower with variable pivot has been studied. In this mechanism, the pivot of the swing follower is installed on a slider with an adjustable track direction, the follower performs a complex planar motion, and the motion range of the output angle can be adjusted according to the output requirements. In order to synthesize this mechanism, firstly, the relevant model is established and the basic structural parameters are optimized by considering the assembly conditions and the pressure angle under the limit position of the movement track of the follower mounting slider. Subsequently, the inverse method and the envelope theory are employed to derive the cam contour coordinates. Finally, the corresponding follower motion law is selected, the corresponding cam contour coordinates are calculated, and the entire cam contour curve is obtained using spline interpolation. An automatic design system for cam contours is developed. The processes are carried out through design examples and verified through motion simulations and prototype experiment. The present work can enrich the design theory of cam-linkage mechanisms.

Rancang Bangun Alat Penampung Buku Berbasis Arduino pada Sistem Pengembalian Buku Layanan Mandiri

This study aims to design and create a book container in a self-service book return system at the Andalusia Library & Knowledge Center UPI YPTK Padang. Currently, the self-service book return system is carried out through a book drop machine. This book container is designed to complement the book drop machine. The returned book is inserted into the slanted gap so that it can slide into the book container. When the book container is empty, the base is at the upper limit position. If a book is entered, the base will automatically drop according to the thickness of the book. And so on, until it is full and the buzzer is active. Thus, it is hoped that book damage can be prevented due to the book falling too far down. The system is designed using ultrasonic sensors to detect upper and lower limits, a Direct Current (DC) motor to move the base down according to the thickness of the book. After testing, the book container works well and is able to withstand loads of up to 22 kg with the number of books between 30 and 50 depending on the size of the book. The DC motor is able to move the book container when the load is maximum. The sensor can detect the thickness of the book, the upper and lower limits and the buzzer can activate when the book is full. Thus, this tool can be used to support the book drop in the self-service book return system.

Rancang Bangun Alat Penampung Buku Berbasis Arduino Pada Sistem Pengembalian Buku Layanan Mandiri

This study aims to design and create a book container in a self-service book return system at the Andalusia Library & Knowledge Center UPI "YPTK" Padang. Currently, the self-service book return system is carried out through a book drop machine. This book container is designed to complement the book drop machine. The returned book is inserted into the slanted gap so that it can slide into the book container. When the book container is empty, the base is at the upper limit position. If a book is entered, the base will automatically drop according to the thickness of the book. And so on, until it is full and the buzzer is active. Thus, it is hoped that book damage can be prevented due to the book falling too far down. The system is designed using ultrasonic sensors to detect upper and lower limits, a DC motor to move the base down according to the thickness of the book. After testing, the book container works well and is able to withstand loads of up to 22 kg with the number of books between 30 and 50 depending on the size of the book. The DC motor is able to move the book container when the load is maximum. The sensor can detect the thickness of the book, the upper and lower limits and the buzzer can activate when the book is full. Thus, this tool can be used to support the book drop in the self-service book return system.

NEW METHODS TO PROTECT YEAR-AROUND OPERATION CANALS FROM SNOW

On the canals of year-around operation, severe snowdrifts concentrated on the surface of the ice cover simultaneously affect both thermal and static loads. When ice melts intensively from the lower surface in areas of accumulation of snow masses, and also due to an increase in the static load from snow, longitudinal cracks form on the ice. The snow saturated with water rising up along the cracks, and a gradual sinking of the snow-ice mass occurs. All this leads to decrease in canal capacity, and in some cases to complete blockage of the flow section by snow-ice mass. The purpose of the paper is to find new ways to protect the canal drift and create an impervious canal profile in areas heavily covered in snow. Snow deposition in the canal bed occurs gradually, starting from the edge of canal closest to the snow collection basin side, followed by an increase in the snowdrift shaft in the direction of the wind as snow blizzard arrives to the canal. We propose the method of protecting the canals from snowdrifts by changing the transverse profile of the canal in the sections highly covered by snow. The transverse canal profile is changed by adding a berm to it with a slope coefficient equal to the coefficient the leeward slope and a height equal to the depth of the canal from the leeward slope depending on exact establishing the limit position of the surface of the snowdrifts, at which the canal is blown without snow deposition, regardless of the amount of snow transfer. The proposed methods can be applied in areas of snow transfer on watering and irrigation canals designed for year-around operation.

Workspace Augmentation for the Large-Scale Spherical Honeycombs Perfusion Using a Novel 5DOF Reconfigurable Manipulator

The volume of workspace is a significant kinematic index of parallel manipulator in some applications of engineering. However, the workspace degradation of the manipulator in extreme position is a demanding issue, which results in a fact that such manipulators cannot satisfy the machining requirement of the maximum limit position for the large-scale complex structural components. In this paper, a novel five degrees-of-freedom (DOF) 5PRR+5PUS-PRPU parallel manipulator (PM) is presented. First, the mobility analysis for the proposed manipulator is carried out, and the inverse kinematics as well as the Jacobian matrix is developed. Then, the workspace of the 5PRR+5PUS-PRPU PM and the 5PUS-PRPU PM is analyzed to study the workspace augmentation of the proposed PM. The workspace comparisons of these two PMs prove that the proposed PM not only can realize the large movement of the moving platform along the z-axis, but also possess larger workspace than the 5PUS-PRPU PM when the moving platform has a large movement along the z-axis. Furthermore, the singularity analysis is also conducted to show the singularity-free workspace of the proposed PM. By the introduction of the reconfigurable 5PRR PM, the proposed manipulator effectively augments the reachable workspace of the moving platform along the z-axis and to some extent also solves the issue of workspace degradation of the PM along z-axis.

Near-optimal solutions and tight lower bounds for the parallel machines scheduling problem with learning effect

In this paper, the parallel machines scheduling problem with Dejong’s learning effect is addressed. The considered problem has a practical interest since it models real-world situations. In addition, this problem is a challenging one because of its NP-Hardness. In this work, a set of heuristics are proposed. The developed heuristics are categorized into two types. The first category is based on the dispatching methods, with new enhancement variants. The second type is more sophisticated and requires solving NP-Hard problems. Furthermore, several lower bounds are developed in order to assess the performance of the proposed heuristics. These lower bounds are based on solving the problem of the determination of the minimum average load under taking into account some observations. Among these observations, the existence of a limit position that the jobs are not allowed to exceed in any optimal schedule. Finally, an extensive experimental study is conducted over benchmark test problems, with up to 1500 jobs and 5280 instances. The obtained results are outperforming those proposed in the literature.

Reading Schmitt from the Sea: Tracing Constitutive Outsiders and Displacing the Conceptual Order (and Ordering) of the Political

ABSTRACT In this article, I offer a displacement of Carl Schmitt’s metaphysical image of a specific epoch and the way it forges a particular construction of the planet, which reveals architectonic traces of a normative framing which authorizes and legitimizes, a specific way of conceiving the appropriate form of the political organization of the world. Inspired by Jacques Derrida’s work, I displace Schmitt’s traditional friend/enemy dualism towards the sea and the conceptual (post) structural limit-position of the pirate. Adopting a Derridean, deconstructionist strategy, I question the way Schmitt conceptually (self-) authorizes his conceptual order (and ordering), identifying some spaces, actions, and categories of subjects as unpolitical . Negatively, I argue, these non- political constructions, these constitutive outsiders , conceptually authorize the line which enables the conditions for conceptualizing and identifying the political. In reading Schmitt from the sea, I invite the reader to reimagine the boundaries of our cartographical political imagination, the limits of our normative conceptual language, and the ways in which the legitimation of exceptional forms of violence may be conceptually articulated, authorized, and legitimized.

On estimating the reduction factor of bridge piers

Estimating the reduction factor for calculating massive reinforced concrete bridge piers was made. For this purpose a quasi-static “force-displacement” diagram was built up using the ANSYS software. This diagram has the form of a bilinear one, and the character of the bilinearity depends on the diameter of the reinforcing bars insignificantly. The percentage of reinforcement affects only the moment when all reinforcement bars begin to flow. The reinforcement flow takes place in the displacement interval from 3 to 5 cm. The collapse will occur when the reaction of the bearing part goes beyond the pier cross-section at pier displacements from 5 to 20 cm. Using “force-displacement” diagram, the behavior of the single-mass model with a bilinear deformation diagram and the limit displacement of 20 cm was analyzed. Then, it became possible to obtain for each accelerogram the limit elastic displacement and the limit position of the point corresponding to the maximum structure displacement during structure oscillations. It was done using real accelerograms of earthquakes with intensity 9 on the MSK scale without normalizing their amplitudes. In this case, long-period accelerograms had smaller peak accelerations, but resulted in greater plastic deformations. As a result, no evident dependence of plastic deformation on the input spectral composition was found and the value of reduction factor K1 turned out to be 0.25-0.27. However, it is shown that this reduction factor cannot be used to make transition from seismic loads obtained on the basis of time-history analysis by accelerograms to design loads.

Prototype Pintu Air Berbasis Android dan Mikrokontroller Menggunakan Bluetooth

Generally, in existing dams facilitated by sluice are used to control the amount of water on that dam. This sluice is controlled by a human that has a duty to maintain the stability of the water on that dams or not to be more than existing limitation. Therefore the doorman clerk must be ready at all times and it is impossible for him to do it over time. The water gate drain human energy when open and then close it again. This tool is using as a replacement for human power. By the statement improved advanced technology development taht combines Android with Bluetooth-based Atmega 328 microcontroller instruments. This remote sluice control works automatically. The Ping sensor measures the level of the water and sluice, after that the recorded data will be processed by microcontroller and send it into the Android through Bluetooth. Besides that, the Android data that consist of water level and sluice will be captured on the LCD screen. On the other hand, the Beeb voice that getting from a buzzer will active when the level of the water sign exceeds 3 cm. In this research, Android is used as a monitoring tool and control system remotely. Furthermore, this tool also uses a DC motor in order to open and close sluice, so it makes the water gate capable to be closed and opened based on expected distance. This system hopefully can automatically open the water gate if the water level higher than a limit position by using an android control system based on operator expectation. That way there is no human power needed to open the water gate. In other words, effectiveness and efficiency will occur.

The Howling Wilderness of the Maladaptive Struggle in Belgrade in New York

Between 1974 and 1975, Zoran Popović, a conceptual artist from Belgrade, Yugoslavia, and his wife Jasna Tijardović, an art historian, spent a year in New York. During that time they engaged closely with the New York Art and Language group. This friendship and collaboration resulted in a rare instance of East-West exchange in Conceptual art: Popović and Tijardović published both co-authored and individual articles in the US journal The Fox, and members of Art and Language (Mel Ramsden, Michael Corris, and Jill Breakstone) gave a seminar in Belgrade's Student Cultural Center in the fall of 1975. One of the most important outcomes of this exchange is Zoran Popović's film Struggle in New York—Борба у Њујорку, which he made on his return visit to New York in the fall of 1976, and which features the members of New York Art and Language and other artists and activists from the downtown Manhattan art scene of the mid-1970s. This essay argues that in this film, Popović uses documentary techniques to establish a space for the display of radical artistic practices that engaged in a vigorous critique of art institutions. In so doing this film marks a limit position of institutional critique that approaches the idea of the abolishment and abandonment of art practice altogether. Further, the essay explores some differences between Conceptual art practice in Yugoslavia and the United States, arguing that Popović uses the crisis that tore the New York Art and Language group apart to address the unraveling of politicized Conceptual art practice in Belgrade's Student Cultural Center.