• Journal of Korean Society of Water and Wastewater
• /
• v.23 no.6
• /
• pp.789-797
• /
• 2009

The flow in the beginning lateral sewer can be characterized as intermittent and unsteady, and a moment maximum flow energy is required to transport fecal solids in the sewer. It is thus difficult to design to satisfy a minimum velocity criteria (0.6m/s), because of the substantially lower discharge in the beginning lateral sewer. This study is the result of a field survey, and aims to determine a design criteria for the minimum slope to prevent sediment in a lateral sewer. The survey performed on the two flat small catchments in Goyang-si consisting of D400mm hume-pipe, aimed to understand the manner in which the scope of a sewer slope has an effect on sediment in the beginning lateral sewer. The survey showed that the sewer slope below 3‰ had sedimentation of 88.7%, while the sewer slope of 3~6‰ had sedimentation of 47.8%. In addition, the minimum design slope was estimated to refer to the result of hydraulic experiments from Public Works Research Institute in Japan. Analysis showed that the D400mm hume pipe should be installed with a slope of 6.5‰ to prevent sediment in the beginning lateral sewer. For future installations, the study results showed that a D300mm plastic pipe requires a minimum slope of 3.5‰, and a D250mm plastic pipe requires a minimum slope of 3.3‰ in the beginning lateral sewer.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.60 no.2
• /
• pp.85-93
• /
• 2018

This study investigated the structural behavior and field applicability of sandwich type GFRP arches with polymer mortar in core. As a result, in case of crack loading and failure loading, total strains at crown were the highest; the fracture strain at crown was 0.01690, which is 4.2 times greater than the fracture strain (0.004) of cement concrete. The 3 % deflection load was 17.42 kN, the flexural strength was $163.98{\times}10^{-3}GPa$, and the flexural elastic modulus was 11.884 GPa. From load-deflection relationship up to 3.5 % deflection, 3D analysis results and experimental values were observed to be almost identical. It was considered reasonable to set a deflection rate limit to be 3 % for structural safety purpose. The standard external flexural strength of semicircular arch used in this study was approximately 2.64 times higher than that of hume pipe (2 type standard) and tripled composite pipe. The external pressure strength at fracture was approximately 1.57 times higher than that of hume pipe. It was confirmed that the implementing semicircular arch had mechanically more advantage than the circular pipe. Optimum member thickness was 8~53 mm according to arch radius of 450~1,800 mm and cover depth of 2~10 m. It was found that the larger strength could be obtained even if the thickness of member was smaller than that of concrete structure. In field application study, figures and equations were derived for obtaining applicable cover depth and optimum member thickness according to loading conditions. These would be useful data for design and manufacture of sandwich type semicircular arch.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.14 no.3
• /
• pp.1519-1526
• /
• 2013

This study reviewed the capturing performance of a canopy hood used in some melting processes of a casting manufacturing factory through a site survey. In addition, this study compared and evaluated the flow field and pressure field for the plans to enhance the hazardous air pollutants collection capacity by using CFD model. The case-2(flange attached + double hood) can be improved in terms of collection performance, but is expected to increase in hood static pressure by about 70% more than the existing structure, so it was shown that its site applicability is not good. It is judged that the shape of case-3(flange attached + double cone attached) is most suitable to improve the suction efficiency. This is because a double cone is installed at the center of the opening to concentrate the flow rate on the edge of the hood and control the hume rising to the center of the hood without a static pressure rise via the slope of the cone.

• International Journal of CAD/CAM
• /
• v.6 no.1
• /
• pp.183-192
• /
• 2006

A CAD/CAM system has been developed for rapid prototyping (RP) of microfluidic devices based on excimer laser micromachining. The system comprises of two complementary softwares. One, the CAM tool, creates part programs from CAD models. The other, the Simulator Tool, uses a part program to generate the laser tool path and the 2D and 3D graphical representation of the machined microstructure. The CAM tool's algorithms use the 3D geometry of a microstructure, defined as an STL file exported from a CAD system, and process parameters (laser fluence, pulse repetition frequency, number of shots per area, wall angle), to automatically generate Numerical Control (NC) part programs for the machine controller. The performance of the system has been verified and demonstrated by machining a particle transportation device. The CAM tool simplifies part programming and replaces the tedious trial-and-error approach to creating programs. The simulator tool accepts manual or computer generated part programs, and displays the tool path and the machined structure. This enables error checking and editing of the program before machining, and development of programs for complex microstructures. Combined, the tools provide a user-friendly CAD/CAM system environment for rapid prototyping of microfluidic devices.

• Journal of Korean Philosophical Society
• /
• v.123
• /
• pp.409-440
• /
• 2012

It is well known that Deleuze began his philosophical work from researching the biographies of many predecessors' such as D. Hume, Lucretius, I. Kant, B. Spinoza, F. W. Nietzsche, H. Bergson, and etc. Among them, especially Spinoza, Nietzsche, and Bergson constitute a foundation supporting the whole idea of Deleuze. He declared that the goal of his early biographical work is a theme converging the identity of two philosophers, Spinoza and Nietzsche, and it shows that these two philosophers had such a huge significance to Deleuze, at least by then. However, we may point out two issues here. The first is why Deleuze, who is recognized as a philosopher of 'difference', deals the identity. The other issue is, what kind of identity exists between the two philosophers, Spinoza and Nietzche. In a common sense, their ideas contradict to each other. Spinoza puts God at the center of his philosophical system, whereas Nietzsche declared 'God is dead'. Though Nietzsche expressed a concurrent opinion with Spinoza at first, it is well known that he turned his side against him soon after and criticized him sharply. There is a conflict at the core of this criticism concerning the existence or non-existence of God. Many think that Spinoza, however, cannot be free from the argument that his philosophy allows a possibility of atheism. Deleuze, who also called Spinoza an atheist, suggested a new viewpoint of the philosophy of Spinoza based on his attribution to the concept of 'power'. On the other hand, Deleuze reinterpreted Nietzsche, where he analyzed 'the will to power' in a totally inventive way. Likewise, the reciprocal communication of ideas connected by the concept of 'power' gives a foundation of identifying the two philosophers to Deleuze. In this paper, considering this reciprocal communication, I intent to reveal the foundation of identity of the two philosophers, Spinoza and Nietzsche, and as a result, investigate what the concept of identity means to Deleuze, the philosopher of difference. Furthermore, we will also take a look at how Deleuze presents a new perspective on the conflict on the existence of God of the two philosophers in the process of validating the identity.

• Journal of Korean Philosophical Society
• /
• v.123
• /
• pp.1-26
• /
• 2012

Ist der Emotivismus eine $mi{\ss}lungene$ Theorie? Nach der Meinung von Jesse Prinz ist es nicht so. Auf der Humeschen Tradition stehend behauptet er, $da{\ss}$ ein moralisches Urteil ohne das Sentiment von Billigung oder $Mi{\ss}billigung$ nicht zustandekommen kann. Ihm zufolge ist Emotion nicht allein mit moralischen Urteilen verbunden, sondern auch eine notwendige und hinreichende Bedingung $daf{\ddot{u}}r$. Der Grund dessen, warum der Emotivisums nicht ${\ddot{u}}berzeugend$ erschien, liegt darin, $da{\ss}$ $f{\ddot{u}}r$ diesen die Verbindung von Emotion und Moral nur auf den $Gef{\ddot{u}}hlsausdruck$ $beschr{\ddot{a}}nkt$ bleibt. Zwar stellt das moralische Urteil Sentiment dar, aber das bleibt eben nicht als ein $blo{\ss}$ $Gef{\ddot{u}}hlsausdruckendes$. Denn die $Moralit{\ddot{a}}t$ ist nicht die einfache Projektion eines subjektiven Zustandes, vielmehr konstruiert die emotionale Reaktion von Billigung oder $Mi{\ss}billigung$ das moralische Urteil. Daher muss der projektistische Gesichtspunkt des expressionistischen Emotivismus modifiziert werden, so $da{\ss}$ der oft dem Emotivismus kritisch zugeschriebene moralische Nihilismus zu ${\ddot{u}}berwinden$ ist. In diesem Zusammenhang $schl{\ddot{a}}g$ Prinz den konstruktiven Sentimentalismus vor, der als eine hybride Theorie des Moralbegriffs von 'biologiscehn Tatsachen' und 'sozialer Konstruktion' darauf zielt, im moralischen Leben eine Stelle auszumanchen, wo Evolution und Kutur zueinander zusammentreffen $k{\ddot{o}}nnen$.