• Composites Research
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• v.18 no.1
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• pp.23-29
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• 2005

In this work, the effect of ozone treatment of montmorillonite (MMT) on the surface characteristics of montmorillonite and the thermal stability of MMT/polypropylene (PP) nanocomposites was investigated. The surface properties of MMT were determined by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopy (XPS). Also, the thermal stability of nanocomposites was investigated in thermogravimetric analysis (TGA). As a result, it was found that the silicate interlayers of the organically modified MMT (D-MMT) were increased by about 11${\AA}$, as compared with the MMT. Also, FT-IR showed that a new peaks at $2800\~2900\;cm^{-1}$ appeared due to the $CH_2$ mode in the D-MMT The ozone treatment of the MMT led to an increase of SiO or $SiO_2$ groups on MMT surfaces, resulting in increasing the oxygen-containing functional groups on MMT. The ozonized MMT had higher thermal stability than that of untreated nanocomposites. This was due to the improvement of interfacial bonding strengths, resulting from the acid-base interfacial interactions between PP and MMT.

• Archives of Plastic Surgery
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• v.40 no.4
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• pp.397-402
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• 2013

Background Fracture-dislocation of the proximal interphalangeal (PIP) joint is a relatively common injury. Various treatments for fracture-dislocation of the PIP joint have been reported. In the present study, we performed open reduction through a midlateral incision using absorbable sutures to reduce the small bone fragments and performed volar plate repair. Methods We treated nine patients with fracture-dislocation of the PIP joint with small fractured bone fragments too small for pinning or screw fixation. Patients with volar plate injury were treated with open reduction and volar plate repair at the periosteum of the middle phalangeal bone base by the modified Kessler method using absorbable sutures. All patients were placed in a dorsal aluminum extension block splint, which maintained the PIP joint in approximately 30 degrees of flexion to avoid excessive tension on the sutured volar plate. Results At a mean final follow-up of postoperative 9 months, all patients were evaluated radiographically and had adequate alignment of the PIP joint and reduction of the displaced bone fragments. Range of motion was improved and there were no complications. Conclusions This technique is an excellent alternative to the current method of treating patients with fracture-dislocations that include small fragments that are too small for pinning or screw fixation. It is a less invasive surgical method and enables stable reduction and early exercise without noticeable complications.

• Journal of Environmental Impact Assessment
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• v.22 no.1
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• pp.89-97
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• 2013

RADCONS Ver. 1.0 (RADiological CONSequence Assessment Program) was developed for radiological risk assessment in this study. A Gaussian plume model was used to analyze the fate and transport of radionuclides released into the air in case of accidents. Both single meterological data and time series meterological data can be used in RADCONS. To assess the radiological risk of the early phase after an accident, ED (Effective Dose) estimated by both deterministic and probabilistic approaches are presented. These EDs by deterministic and probabilistic will be helpful to efficient decision making for decision makers. External doses from deposited materials by time are presented for quantifying the effects of mid and late phases of an accident. A radiological risk assessment was conducted using RADCONS for an accident scenario of 1 Ci of Cs-137. The maximum of ED for radii of 1,000 meters from the accident point was 8.51E-4 mSv. After Monte-Carlo simulation, considering the uncertainty of the breathing rate and dispersion parameters, the average ED was 8.49E-4, and the 95 percentile was 1.10E-3. A data base of the dose coefficients and a sampling module of the meteorological data will be modified to improve the user's convenience in the next version.

• The Journal of Advanced Prosthodontics
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• v.5 no.1
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• pp.58-66
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• 2013

PURPOSE. The purpose of this study was to decide the most appropriate point on tragus to be used as a reference point at time of marking ala tragus line while establishing occlusal plane. MATERIALS AND METHODS. The data was collected in two groups of subjects: 1) Dentulous 2) Edentulous group having sample size of 30 for each group with equal gender distribution (15 males, 15 females each). Downs analysis was used for base value. Lateral cephalographs were taken for all selected subjects. Three points were marked on tragus as Superior (S), Middle (M), and Inferior (I) and were joined with ala (A) of the nose to form ala-tragus lines. The angle formed by each line (SA plane, MA plane, IA plane) with Frankfort Horizontal (FH) plane was measured by using custom made device and modified protractor in all dentulous and edentulous subjects. Also, in dentulous subjects angle between Frankfort Horizontal plane and natural occlusal plane was measured. The measurements obtained were subjected to the following statistical tests; descriptive analysis, Student's unpaired t-test and Pearson's correlation coefficient. RESULTS. The results demonstrated, the mean angle COO (cant of occlusal plane) as $9.76^{\circ}$, inferior point on tragus had given the mean angular value of IFH [Angle between IA plane (plane formed by joining inferior point-I on tragus and ala of nose- A) and FH plane) as $10.40^{\circ}$ and $10.56^{\circ}$ in dentulous and edentulous subjects respectively which was the closest value to the angle COO and was comparable with the values of angle COO value in Downs analysis. Angulations of ala-tragus line marked from inferior point with occlusal plane in dentulous subject had given the smallest value $2.46^{\circ}$ which showed that this ala-tragus line was nearly parallel to occlusal plane. CONCLUSION. The inferior point marked on tragus is the most appropriate point for marking ala-tragus line.

• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.755-761
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• 2015

Photocatalytic VOCs removal test in gas phase is generally performed by placing the light source on the outside due to maintaining a constant temperature inside the test chamber. The distance between light source and photocatalysts is importantin the VOC degradation test since the intensity of light is rapidly decreased as the distance farther. Especially, for the choice of light source as UVLED, this issue is more critical because UVLED light source emits lots of heat and it is hard to measure the exact concentration of VOCs due to changed temperature in the test chamber. In this study, we modified VOC removal test chamber base on the protocol of air cleaner test and evaluated the efficiency of photocatalystunder UVLED irradiation. Photocatalystsof two different samples (commercial $TiO_2$ and the synthesized vanadium doped $TiO_2$) weretested for the p-xylene degradation in the closed chamber system and compared with each other in order to exclude any experimental uncertainties. During the VOC removal test, VOC concentrations were monitored and corrected at regular time intervals because the temperature in the chamber increases ${\sim}20^{\circ}C$ due tothe heat of UVLED. The results showed that theconversion ratio of p-xylene has 40~43% difference before and after the temperature correction. Based on those results, we conclude that the VOC concentration correction must be required for the VOC removal test in a closed chamber system under UVLED light source and obtained the corrected efficiencies of various photocatlysts.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.3
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• pp.223-229
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• 2015

Surface modification is a technology to form a new surface layer and overcome the intrinsic properties of the base material by applying thermal energy or stress onto the surface of the material. The purpose of this technique is to achieve anti-corrosion, beautiful appearance, wear resistance, insulation and conductance for base materials. Surface modification techniques may include plating, chemical conversion treatment, painting, lining and surface hardening. Among which, a surface modification process using electrolytes has been investigated for a long time in connection with research on its industrial application. The technology is highly favoured by various fields because it provides not only high productivity and cost reduction opportunities, but also application availability for components with complex geometry. In this study, an electrochemical experiment was performed on the surface of 5083-O Al alloy to determine an optimal electrolyte temperature, which produces surface with excellent corrosion resistance under marine environment than the initial surface. The experiment result, the modified surface presented a significantly lower corrosion current density with increasing electrolyte temperature, except for $5^{\circ}C$ of electrolyte temperature at which premature pores was created.

• Proceedings of the KSRS Conference
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• v.2
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• pp.551-554
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• 2006

House management is very important in water resource protection in order to provide sustainable drinking water for about four millions population in northern Taiwan. House management can be a simple job that can be done without any ingredient of remote sensing or geographic information systems. Remote sensing and GIS integration for house management can provide more efficient management prescription when land use enforcement, soil and water conservation, sewage management, garbage collection, and reforestation have to be managed simultaneously. The objective of this paper was to integrate remote sensing and GIS to manage houses in a water resource protection district. More than four thousand houses have been surveyed and created as a house data base. Site map of every single house and very detail information consisting of address, ownership, date of creation, building materials, acreages floor by floor, parcel information, and types of house condition. Some houses have their photos in different directions. One house has its own card consists these information and these attributes were created into a house data base. Site maps of all houses were created with the same coordinates system as parcel maps, topographic maps, sewage maps, and city planning maps. Visual Basic.NET, Visual C#.NET have been implemented to develop computer programs for house information inquiry and maps overlay among house maps and other GIS map layers. Remote sensing techniques have been implemented to generate the background information of a single house in the past 15 years. Digital orthophoto maps at a scale of 1:5000 overlay with house site maps are very useful in determination of a house was there or not for a given year. Satellite images if their resolutions good enough are also very useful in this type of daily government operations. The developed house management systems can work with commercial GIS software such as ArcView and ArcPad. Remote sensing provided image information of a single house whether it was there or not in a given year. GIS provided overlay and inquiry functions to automatically extract attributes of a given house by ownership, address, and so on when certain house management prescriptions have to be made by government agency. File format is the key component that makes remote sensing and GIS integration smoothly. The developed house management systems are user friendly and can be modified to meet needs encountered in a single task of a government technician.

• The KIPS Transactions:PartC
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• v.16C no.2
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• pp.151-164
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• 2009

The importance of sensor networks as a base of ubiquitous computing realization is being highlighted, and espicially the security is recognized as an important research isuue, because of their characteristics.Several efforts are underway to provide security services in sensor networks, but most of them are preventive approaches based on cryptography. However, sensor nodes are extremely vulnerable to capture or key compromise. To ensure the security of the network, it is critical to develop security Intrusion Detection System (IDS) that can survive malicious attacks from "insiders" who have access to keying materials or the full control of some nodes, taking their charateristics into consideration. In this perper, we design a distributed and adaptive IDS architecture on sensor networks, respecting both of energy efficiency and IDS efficiency. Utilizing a modified HEED algorithm, a clustering algorithm, distributed IDS nodes (dIDS) are selected according to node's residual energy and degree. Then the monitoring results of dIDSswith detection codes are transferred to dIDSs in next round, in order to perform consecutive and integrated IDS process and urgent report are sent through high priority messages. With the simulation we show that the superiorities of our architecture in the the efficiency, overhead, and detection capability view, in comparison with a recent existent research, adaptive IDS.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.250-251
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• 2023

The pallet, typically a form of tertiary packaging, is a flat structure used as a base for the unitization of goods in the supply chain. In addition, standard pallets such as T-11 and T-12 are used throughout the logistics industry to reduce the cost and enhance the efficiency of transportation. However, in the case of special cargo, it is impossible to handle such cargo using a standard pallet due to its size and weight, so many have developed and are now using their customized pallet. Therefore, this study suggests a pallet size optimization method to calculate the optimal pallet size, which minimizes the loss of space on a pallet. The main input features are the specifications and the storage quantity of each cargo, and the optimization method that has modified the Neighborhood Search Algorithm calculates the optimal pallet size. In order to verify the optimality of the developed algorithm, a comparative analysis has been conducted through simulation.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.1
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• pp.1-9
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• 2015

Purpose: The purpose of this study was to evaluate the mechanical properties of several dual-cure cements by different curing modes. Materials and Methods: One resin-modified glass ionomer cement (FujiCEM 2), two conventional dual-cure resin cements (RelyX ARC, Multilink N), and two dual-cure self-adhesive resin cements (RelyX U200, G-CEM LinkAce) were used. To evaluate the influence of the curing methods, each cements divided into four conditions (n = 20); Condition 1: self-curing for 10 minutes, Condition 2: immediate after 20 seconds light-curing, Condition 3: 24 hours after self-curing, Condition 4: 24 hours after light-curing. The compressive strength and diametral tensile strength were measured with a universal testing machine. All data were statistically analyzed using t-test, one-way ANOVA and Scheffe's test. Results: The results showed the compressive strength and diametral tensile strength after 24 hours in all curing modes were higher than immediate except RelyX ARC light-cured and Multilink N light-cured. The FujiCEM 2 showed lowest values (P < 0.05). Conclusion: The outcome was cement-depend, but there is no significant difference about compressive strength and diametral tensile strength between dual-cure self-adhesive resin cements and conventional resin cements. And this result will be used as a base line data selecting resin cement for favorable long-term prognosis.