• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.1
• /
• pp.79-84
• /
• 2004

A light-guide is one of several important components of backlight unit in TFT-LCD. The manufacturing technology and optical system design of the light guide is very sensitive to quality and cost of the TFT-LCD module. In the present study a new manufacturing method which is called as direct surface forming(DSF) has been tested under various conditions. DSF is very similar to the well-known hot embossing except for partial contact between mold and substrate. The final V-groove pattern shows different shapes depend on the temperature of mold surface, contact time of mold and depth of V-groove.

• Journal of Powder Materials
• /
• v.14 no.3 s.62
• /
• pp.185-189
• /
• 2007

Various approaches have been proposed to increase the green density. Warm compaction method has been used for the reduction of residual stress, the improvement of magnetic properties and the higher densities. In this work, the effect of warm compaction on green density of Fe powder was investigated. After ball-milling of Fe oxide powder for 30 hours, Fe oxide powder was reduced through the hydrogen reduction process. The pure Fe powder and polymer binder were mixed by 3-D tubular mixer. And then the mixed powder was warm-compacted with various compaction pressure and binder contents. The green density of specimen was added polyvinyl binder was higher than any other specimens.

• The KSFM Journal of Fluid Machinery
• /
• v.9 no.5 s.38
• /
• pp.7-13
• /
• 2006

In the present study, we develop an analysis module to be applicable to design of sliding thrust bearings. The pressure equation is solved by using the finite element method. Average lubricant temperature is obtained from using the energy balance method. The module developed has been applied to three types of thrust bearing, such as tapered-land thrust bearings of angular and diamond types, and tilting-pad thrust bearings. Effects of the dam of the tapered-lad thrust bearings have also been investigated. It has been seen that the tapered-land thrust bearings of angular type result in the highest load capacity, while the tilting pad thrust bearings result in the lowest lubricant temperature. It has also been seen that the dam in the tapered-land thrust bearings increases both the load capacity and lubricant temperature.

• Transactions of Materials Processing
• /
• v.7 no.6
• /
• pp.594-602
• /
• 1998

The design analysis of axisymmetric, multi-stage deep drawing dies was performed using the rigid-viscoplastic finite element formulation. In the formulation the axisymmetric CFS algorithm was employed. Hill's non-quadratic normal anisotropic yield criterion and isotropic hardening rule were considered. For trial initial displacements and tool contact points. the geometric force equilibrium method was adopted. In order to see the validity of the formulation, the multi-stage deep drawing processes of shell-cylinder front part of hydraulic booster were simulated. The simulation showed good agreements with measurments and PAM-STAMP results.

• Journal of the Korean Society for Precision Engineering
• /
• v.13 no.3
• /
• pp.80-93
• /
• 1996

A 2-dimensional FEM/GEM program was developed under the plane strain assumption using linear line elements for analyzing stretch/draw forming operations of an arbitrarily shaped draw-die. FEM formulation adopted a new algorithm for solving force equilibrium as well as non-penetration condition simultaneously. Also, a rigid-viscoplastic material model with Hill's normal anisotropic yield condition and rate-sensitive hardening law is assumed, along with the Coulomb friction law in the contact regions. For the case of numerical divergence at nearly final forming stages, geometric force equilibrium method(GEM) is also introduced. The developed program was tested by simulating the forming processes of cylindrical punch/open die, and the drawing processes of automotive oilpan and hood inner panel in order to verify the usefulness and validity of FEM/GEM formulation. The numerical simulation verified the validity and robustness of developed program.

• Journal of the Korean Society for Precision Engineering
• /
• v.10 no.1
• /
• pp.100-107
• /
• 1993

In this study, it is analyzed that an electromagnet whose generating force is proportional to constant current through coil in its coperating range. To find arelation between magnetic force and the structure in electromagnet, computer simulation method is used by permeance modeling method. When the electromagnet is applied to flow control valve, the relation between input current and flow is found. In order to get a reliability of computer simluation, the simulation results are compared to the experimental result. As the simulation is processed repeatedlyl. it is found that the gap size between plunger and guide steel and the length of tapered brass ring are important factors in electromaget.

• Proceedings of the Korean Society of Disaster Information Conference
• /
• 2022.10a
• /
• pp.160-161
• /
• 2022

영국의 "기업과실치사법", 캐나다 및 호주의 기업처벌을 강화하기 위해서 형법을 개정하였음에도 불구하고 산업재해 감소 효과는 미미하다. 건설 현장의 불안전한 상태 방치 및 가설구조물에서 강도 높은 안전사고가 다수 발생하고 있다. 본 연구에서는 이러한 안전사고 예방을 위해 안전관리 실명제의 중요도 순위를 전문가 설문으로 도출하였다. 건설현장 전문가를 대상으로 AHP모형을 통해 중요도 분석한 결과 상위계층은 건설기계가 가장 중요하다고 보았으며, 하위계층의 안전시설물 관리에서는 개구부, 건설기계에서는 타워크레인, 관리실명제에서는 "산업안전보건법" 상에 의한 관리, 안전관리조직에서는 CEO의무가 가장 중요하다고 보았다. 안전관리실명제의 기대되는 역할은 중대재해처벌법이 예방에 힘쓰기 보다는 방어에 온힘을 다하느라 예방의 기능이 저하되고 있다. 이러한 역 기능을 바로잡기 위해 안전관리실명제는 중요하다.

• Korean Journal of Environment and Ecology
• /
• v.30 no.4
• /
• pp.676-683
• /
• 2016

This study was conducted using the Wild -Tracker (WT-300, GPS-Mobile Phone Based Telemetry KoEco) to understand the habitats of the spot-billed duck wintering in urban and rural areas and provide the results as the basic data for the protection and management of the habitats of the waterbirds in Korea. Study areas consisted of the Anseong stream in Gyeonggi-do and the Sansu reservoir in Haenam. Five spot-billed ducks were captured by region, and we attached Wild-Tracker to each of the spot-billed ducks. We analyzed the tracking location data using ArcGIS 9.x and calculated Kernel Density Estimation (KDE) and Minimum Convex Polygon (MCP). The average home-range measured by MCP was $250.8km^2$(SD=195.3, n=5) in Anseong and was $89.1km^2$ (SD=69.6, n=5) in Haenam. 50% home-range measured by KDE was $21.8km^2$ (SD=26.9, n=5) in Anseong and $3.5km^2$ (SD=2.2, n=5) in Haenam, indicating a narrow home range in Haenam. During the winter season, both wetland and paddy field were mostly used as habitats in Anseong and Haenam. While the paddy field utilization rate was high in the daytime in Haenam, it was high in the nighttime in Anseong. By late winter, Haenam's day time paddy field utilization rate and Anseong's night time paddy field utilization rate increased.

• Korean Journal of Environment and Ecology
• /
• v.33 no.1
• /
• pp.1-8
• /
• 2019

Pintail (Anas acuta) is the major wintering bird in South Korea and known as a major mediator of the highly pathogenic avian influenza (HPAI). Pintail migrates long distances between Russian Siberia and Korea. This species prefers a rice paddy area as their winter habitat. The purpose of this study is to provide the data necessary for the conservation and management of bird habitats in Korea by understanding the wintering home-range and habitat of pintail in Korea. We captured six pintails using a cannon-net in the winter of 2015 and attached the GPS-mobile phone based telemetry (WT-300) on them to study the wintering home-range and wintering habitat. We analyzed the tracking location data using ArcGIS 9.0 Animal Movement Extension and calculated Kernel Density Estimation (KDE) and Minimum Convex Polygon (MCP). The average home-range in the wintering ground analyzed by MCP was $677.3km^2$ (SD=130.2, n=6) while the maximum and minimum were $847.7km^2$ and $467.5km^2$, respectively. Extents of home-range analyzed by KDE were $194.7km^2$ (KDE 90%), $77.4km^2$ (KDE 70%), and $35.3km^2$ (KDE 50%). The pintails mostly used both sea and paddy field as habitat in the winter season and utilized paddy fields more during the nighttime and than the daytime. We concluded that the home-range and habitat of pintails in the winter could be used as the reference data for the preservation of species, management of habitats, and coping with a breakout of HPAI.

• Journal of Legislation Research
• /
• no.55
• /
• pp.137-166
• /
• 2018

Wenn nach dem starken Trinken etwas strafbares passiert, so ist das Gesamtverhalten als $strafw{\ddot{u}}rdig$ und strafbar anzuerkennen. Aber nach dem Schuldprinzip handelt ohne Schuld, wer bei Begehung der Tat $unf{\ddot{a}}hig$ ist, das Unrecht der Tat einzusehen oder nach dieser Einsicht zu handeln(Koinzidenzprinzip). Die Rechtsfigur der "actio libera in causa" dient dazu, diese in $h{\ddot{a}}ufigen$ $F{\ddot{a}}llen$ als kriminalpolitisch $unerw{\ddot{u}}nscht$ empfundene $L{\ddot{u}}cke$ zu umgehen. Dabei kommt auch dem Vollrauschtatbestand in der Praxis $erh{\ddot{o}}hte$ Bedeutung zu. Der deutsche Gesetzgeber war sich bei der Aufnahme des Vollrauschtatbestandes in das Gesetz durchaus $bewu{\ss}t$, $da{\ss}$ die Vorschrift eine Ausnahme zur Schuldzurechnungsregelung darstellte. Er $w{\ddot{a}}hlte$ jedoch die Form eines $selbst{\ddot{a}}ndigen$ Tatbestandes, um die Durchbrechung des reinen Schuldprinzips $ertr{\ddot{a}}glich$ zu machen. Der Vollrauschtatbestand ist ein abstraktes $Gef{\ddot{a}}hrdungdsdelikt$ -demnach die im Rausch verwirklichte rechtswidrige Tat nur objektive Bedingung der Strafbarkeit ist -, das sachlich eine Schuldzurechnungsregelung $enth{\ddot{a}}lt$, und zwar eine Ausnahme $gegen{\ddot{u}}ber$ die Regelungen ${\ddot{u}}ber$ Schuldzurechnung. Dieser Vollrauschtatbestand ist dennoch als regitime $Erg{\ddot{a}}nzung$ der in Schuldzurechnungsregelungen beschriebenen $Schuldzurechnungsgrunds{\ddot{a}}tze$ anzusehen. Er steht $n{\ddot{a}}mlich$ in Einklang mit dem Schuldgrundsatz, wenn als subjektives Tatbestandsmerkmal des Vollrausches die Kenntnis der $Gef{\ddot{a}}hrlichkeit$ des Rauschzustandes $f{\ddot{u}}r$ die Begehung von Delikten vorausgesetzt wird.