• Journal of Surface Science and Engineering
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• v.37 no.1
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• pp.22-27
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• 2004

Copper electroforming process has been applied to duplicate Koryo Tripitaka (Taejang'kyong), wooden printing block. Thin copper replica printing plates of 1 mm thickness was successfully manufactured from the printing face (54.5${\times}$25.5 cm) of wooden printing plate. Major processes are (1) silicon rubber replication of the master (2) silvering on silicon rubber (3) copper electroforming (4) separation of copper from the silicon mandrel (5) final coloring by brass plating and trimming. This process has various Potential applications in making thin metallic objects such as plaques, statues, bust and hollow metal objects for jewelry.

• IE interfaces
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• v.21 no.4
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• pp.418-434
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• 2008

This paper studied issues in decision making on the production control policy of a cathode plate manufacturing process in zinc refining plant. The present production system has a long lead time from raw materials (aluminum plate) to products (cathode plate) due to many WIP inventories. Because WIP inventories are stocked at each process and moved from one place to another frequently, they are the main cause of inefficiency in the process. In this paper, to solve this problem, several production control policies have been identified and studied. Several simulation models are used to compare the performances of these production control policies. The output lead time and WIP (Work In Process) of real production system are compared with those of simulation models. PUSH, CONWIP, DBR, KANBAN and CONWIP-DBR models have been used to simulate and review the optimized production control policy that achieves the target output quantities with decreased lead time and WIP. The simulation results of each production control policy show that CONWIP and CONWIP-DBR models are the good production control policy under the present production system. Especially in present production system, CONWIP with one parameter is easier control policy than CONWIP-DBR with two parameters. Therefore CONWIP has been selected as the best optimum production control policy. With CONWIP, lead time has been reduced by 97% (from 6,653 to 187 minute) and WIP has been reduced from 1,488 to 53, compared to the present system.

• Journal of Power System Engineering
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• v.19 no.2
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• pp.78-83
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• 2015

In Korea, multi-housing in one of the most common types of residential space due to its easy management and convenience. In particular, south-facing plate-type(一) multi-housing has attracted a great deal of public interest because it consumes less energy compared with other types of multi-housing, making it advantageous from an energy-saving perspective. Although there have been many studies on the annual energy consumption of multi-housing in relation to building shape and area of window, there have not been sufficient research on the annual energy consumption of multi-housing in relation to individual units of the multi-housing. The purpose of this study is to propose a strategy for reducing energy consumption in plate-type(一) multi-housing, taking the units with the lowest energy consumption as the standard. The result, Standard Models's energy load was as 4000 ~ 5600kWh, and Passive Houses's energy load was less than Stand Models at the 1600kWh.

• 한국태양에너지학회:학술대회논문집
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• 2009.04a
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• pp.61-65
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• 2009

Window integrated solar collector is to simply install inside of the existing double glass window frame. Double glass window frame is consist of inner glass of Low-E coating and Silver coating, and outer glass of low iron reinforced glass. In order to secure natural lighting in a room, only 50% of window frame is covered with solar collectors. Solar absorption or transmission rate varies seasonally depending on sun angles. Part of inner glass where right behind of the solar plate is covered with silver coating to increase absorption rate of solar plate. The collector is made of a copper serpentine where aluminum fins are soldering. To improve the effect of insulation of inside of the window frame is recommend vacuum. As a result, we are making the 3th sample and will archieve below $F_RU_L=7.5W/m^2^{\circ}C$ that is the account of heat lossed, and above $F_R({\tau}{\alpha})=0.45$.

• Biomaterials and Biomechanics in Bioengineering
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• v.5 no.1
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• pp.37-50
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• 2020

Development of lightweight implant plates are important to reduce the stress shielding effect for a prosthesis of femur bone fractures. Stainless steel (SS-316L) is a widely used material for making implants. Stress shielding effect and other issues arise due to the difference in mechanical properties of stainless steel when compared with bone. To overcome these issues, composite materials seem to be a better alternative solution. The comparison is made between two biocompatible composite materials, namely Ti-hydroxyapatite and Ti-polypropylene. "Titanium (Ti)" is fiber material while "hydroxyapatite" and "polypropylene" are matrix materials. These two composites have Young's modulus closer to the bone than stainless steel. Besides the variety of bones, present paper constrained to femur bone analysis only. Being heaviest and longest, the femur is the most likely to fail among all bone failures in human. Modelling of the femur bone, screws, implant and assembly was carried out using CATIA and static analysis was carried out using ANSYS. The femur bone assembly was analyzed for forces during daily activities. Ti-hydroxyapatite and Ti-polypropylene composite implants induced more stress in composite implant plate, results less stress induced in bone leading to a reduction in shielding effect than stainless steel implant plate thus ensuring safety and quick healing for the patient.

• Earthquakes and Structures
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• v.11 no.1
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• pp.63-82
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• 2016

In this study, the bending and dynamic behaviors of laminated composite plates is examined by using a refined shear deformation theory and developed for a bending analysis of orthotropic laminated composite plates under various boundary conditions. The displacement field of the present theory is chosen based on nonlinear variations in the in-plane displacements through the thickness of the plate. By dividing the transverse displacement into the bending and shear parts and making further assumptions, the number of unknowns and equations of motion of the present theory is reduced and hence makes them simple to use. In the analysis, the equation of motion for simply supported thick laminated rectangular plates is obtained through the use of Hamilton's principle. Numerical results for the bending and dynamic behaviors of antisymmetric cross-ply laminated plate under various boundary conditions are presented. The validity of the present solution is demonstrated by comparison with solutions available in the literature. Numerical results show that the present theory can archive accuracy comparable to the existing higher order shear deformation theories that contain more number of unknowns.

• Computers and Concrete
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• v.22 no.2
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• pp.133-142
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• 2018

The deterioration of existing bridges has become a major problem around the world. In the paper, a new model and an associated stress checking method are proposed for concrete box girders strengthened by external prestressing. The new model called the spatial grid model can analyze all the spatial behaviors clearly by transforming the box girder into discrete orthogonal grids which are equivalent to plate elements. Then the three-layer stresses are employed as the stress checking indices to evaluate the stress state of the plate elements. The initial stress check before strengthening reveals the cracked and potential cracking areas for existing bridges, making the strengthening design more targeted and scientific; the subsequent stress check after strengthening evaluates the strengthening effect and ensures safety. A deficient bridge is selected as the practical example, verifying the accuracy and applicability of the proposed model and stress checking method. The results show that principal stresses in the middle layer of plate elements reflect the main effects of external prestressing and thus are the key stress checking indices for strengthening. Moreover, principal stresses check should be conducted in all parts of the strengthened structure not only in the webs. As for the local effects of external prestressing especially in the areas near anchorage and deviator, normal stresses check in the outer and inner layers dominates and local strengthening measures should be taken if necessary.

• Clinics in Shoulder and Elbow
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• v.20 no.4
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• pp.230-235
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• 2017

Background: Neer type II distal clavicle fractures have the drawback of coracoclavicular instability and insufficient distal bony fragment, thereby making it difficult to achieve adequate fixation. Although various surgical treatments have been described for Neer type II fracture, the optimal treatment remains controversial. This study reports the clinical results and usefulness of anatomical locking plate with additional K-wire fixation. Methods: A totally of 21 patients with type II distal clavicle fracture were included in the study. The surgical procedure reduced the fracture temporarily; it included insertion of one or two K-wire from the lateral margin of the distal fragment to the proximal fragment through the fracture site, followed by application and fixation of the locking plate. The bony union and migration of K-wire was evaluated in the follow-up radiography. The coracoclavicular distance and acromioclavicular joint arthrosis were assessed at the final follow-up. The Constant Score (CS) and Korean Shoulder Score (KSS) were evaluated for clinical scoring. Results: Bone union was achieved in all cases. At the final follow-up, coracoclavicular distance of the injured shoulder was increased, as compared to the intact shoulder (p=0.002), with no accompanying clinical symptoms. No K-wire migration was observed. At the final follow-up, K-wire irritation was observed in two cases and acromioclavicular arthrosis in one case, with no other adverse effects. Pain visual analogue scale, CS, and KSS were improved in all cases. Conclusions: The method of anatomical locking plate with additional K-wire fixation could be useful in achieving beneficial clinical results.

• Transactions of Materials Processing
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• v.29 no.4
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• pp.194-202
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• 2020

In this paper, experimental and numerical study on a combined sheet metal forming and plate forging of a seal part of a passenger car's hub bearing is conducted to develop the new process of which target is to remove machining process by plate forging and to achieve near-net shape manufacturing. The previous process of a sheet metal forming inevitably needed a machining process for making stepped sheet after conventional sheet metal forming in a progressive way. The stepped sheet is intended to be formed by plate forging in this study. Through the systematic way of developing the combined forming process using solid elements based-elastoplastic finite element method (FEM), several conceptual designs are made and an optimized process design in terms of geometric dimensioning and tolerance of straightness of the thin part is found, which is exposed to bending in metal forming of axisymmetric part. The predicted straightness measured by the slope angle of the tilted thin region is compared with the experimental straightness, showing that they are in a good agreement with each other. Through this study, a systematic approach to optimal process design, based on elastoplastic FEM with solid elements, is established, which will contribute to innovating the conventional small-scaled sheet metal forming processes which can be dealt with by solid elements.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.135-139
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• 2006

Most bacteria form biofilm as self-defence system, making efficient food sanitization, preservation, and instrument washing more difficult. Biofilm formation of Salmonella, E. coli, B. cereus, and S. aureus was observed during 24 hr food preservations by performing microtiter plate and glass wool assays. Most cells formed biofilm and attached onto glass wool. When biofilm formation and injury were analyzed on the microtiter plate, 10 and 20% acid-injured E. coli and S. aureus, respectively, 30-50% cold temperature $(4^{\circ}C)-injured$ B. cereus and E. coli, and 30-55% 6% sodium chloride solution-injured Salmonella showed significant biofilm formation. Results indicate biofilm formation level differed within species depending on type of stress.