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In order to reduce the large damage caused by train derailment, protective facilities of various shapes and conditions can be installed on railroad tracks. These protective facilities are referred to as derailment containment provisions (DCPs) and three different types are used worldwide. However, there are no clear standards for DCPs design such as installation location, size, and design load, and performance verification of DCPs installed in the actual railway field is not sufficiently performed. In this paper, the functionality of DCPs is analyzed through the full-scale derailment test. In order to propose a method for estimating the collision load acting on the DCP type I after derailment, the experimental results and simulation results are compared. The function of DCP type I according to the change of the vehicle's center of gravity is identified through comparative analysis of the post derailment behavior.

Purpose: In this study, we aim to study the functionality of multiple effects of peptide collagen and naturally derived compounds through in vitro experiments and human application tests. Method: Cytotoxicity of inner beauty film (IBF), pro-collagen generation ability, elastase and collagenase inhibition, DPPH radical scavenging and tyrosinase inhibition ability were measured, and skin improvement, through in vitro and human application test. Results: Cytotoxicity was not confirmed up to 1000 μg/mL. Elastase inhibition was 7.2% at a concentration of 125 μg/mL, and collagenase showed an inhibition rate of 16.3% at 31.3 μg/mL. The pro-collagen synthesis showed expression of 34%, compared with the negative control when the concentration was 62.5 μg/mL. The antioxidant activity of 250 μg/mL and whitening effect of 62.5 μg/mL are showed in the Results section, and there was no observed deformation or color change even after confirming the stability for 6 months. Even in the human clinical study, the wrinkle improvement before and after using the IBF was 32.2% at maximum, skin melanin and brown spot improvement was 32.5%, pore improvement was 31.5%, and skin density improvement was 12.8%, as shown in the Results section. Conclusion: Therefore, the IBF containing the complex of peptide collagen and naturally derived compounds has a positive effect on wrinkle improvement, skin melanin and brown spot improvement, skin pore improvement, and skin density improvement, as well as exhibiting antioxidant and whitening effects. As a result, IBF can be developed as a key material for cosmetics and foods.

Purpose: This study aimed to determine the optimal blending ratio of extracts of Hippophae rhamnoides (H. rhamnoides ) fruit, Rubus fruticosus (R. fruticosus ) leaf, and Perillae folium (P. folium) leaf as a potential functional material for antiwrinkle, antioxidant, anti-inflammatory, and whitening properties. Methods: We used the design of experiment (DOE) efficacy method to identify the optimal blend ratio for a natural extract complex. In addition, we tested the efficacy of the extract complex and the individual extracts by experiments, including elastase inhibition assay, NO inhibition assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay, tyrosinase inhibition assay, and ROS inhibition assay. Results: DOE methods using natural extracts showed that the most efficacious ratio of H. rhamnoides fruit: R. fruticosus leaf: P. folium leaf was 0.25:0.7:0.05. At this ratio, the elastase inhibitory effect, an indicator of wrinkle improvement, was 28% compared to the control. The antioxidant activity was 71.8% higher than the control. Additionally, NO formation was significantly suppressed by the extract complex. Tyrosinase inhibitory activity, a whitening index, showed 24.4% improvement over the control. Finally, hydrogen peroxide-induced cytotoxicity was significantly inhibited following treatment with the extract complex. Conclusion: The natural extract complex of H. rhamnoides , R. Fruticosus , and P. folium was found to have beneficial wrinkle improvement, antioxidant, anti-inflammatory, and whitening effects, and has potential as a functional cosmetic material.

Background: Preterm birth is a known leading cause of neonatal mortality and morbidity. The underlying causes of pregnancy-associated complications are numerous, but infection and inflammation are the essential high-risk factors. However, there are no safe and effective preventive drugs that can be applied to pregnant women. Objective: The objectives of the study were to investigate a natural product, Abeliophyllum distichum leaf (ADL) extract, to examine the possibility of preventing preterm birth caused by inflammation. Methods: We used a mouse preterm birth model by intraperitoneally injecting lipopolysaccharides (LPS). ELISA, Western blot, real-time PCR and immunofluorescence staining analyses were performed to confirm the anti-inflammatory efficacy and related mechanisms of the ADL extracts. Cytotoxicity and cell death were measured using Cell Counting Kit-8 (CCK-8) analysis and flow cytometer. Results: A daily administration of ADL extract significantly reduced preterm birth, fetal loss, and fetal growth restriction after an intraperitoneal injection of LPS in mice. The ADL extract prevented the LPS-induced expression of TNF-&alpha, in maternal serum and amniotic fluid and attenuated the LPS-induced upregulation of placental proinflammatory genes, including IL-1&beta, IL-6, IL-12p40, and TNF-&alpha, and the chemokine gene CXCL-1, CCL-2, CCL3, and CCL-4. LPS-treated THP-1 cell-conditioned medium accelerated trophoblast cell death, and TNF-&alpha, played an essential role in this effect. The ADL extract reduced LPS-treated THP-1 cell-conditioned medium-induced trophoblast cell death by inhibiting MAPKs and the NF-&kappa, B pathway in macrophages. ADL extract prevented exogenous TNF-&alpha, induced increased trophoblast cell death and decreased cell viability. Conclusions: We have demonstrated that the inhibition of LPS-induced inflammation by ADL extract can prevent preterm birth, fetal loss, and fetal growth restriction.

Background: Preterm birth is a known leading cause of neonatal mortality and morbidity. The underlying causes of pregnancy-associated complications are numerous, but infection and inflammation are the essential high-risk factors. However, there are no safe and effective preventive drugs that can be applied to pregnant women. Objective: The objectives of the study were to investigate a natural product, Abeliophyllum distichum leaf (ADL) extract, to examine the possibility of preventing preterm birth caused by inflammation. Methods: We used a mouse preterm birth model by intraperitoneally injecting lipopolysaccharides (LPS). ELISA, Western blot, real-time PCR and immunofluorescence staining analyses were performed to confirm the anti-inflammatory efficacy and related mechanisms of the ADL extracts. Cytotoxicity and cell death were measured using Cell Counting Kit-8 (CCK-8) analysis and flow cytometer. Results: A daily administration of ADL extract significantly reduced preterm birth, fetal loss, and fetal growth restriction after an intraperitoneal injection of LPS in mice. The ADL extract prevented the LPS-induced expression of TNF-α in maternal serum and amniotic fluid and attenuated the LPS-induced upregulation of placental proinflammatory genes, including IL-1β, IL-6, IL-12p40, and TNF-α and the chemokine gene CXCL-1, CCL-2, CCL3, and CCL-4. LPS-treated THP-1 cell-conditioned medium accelerated trophoblast cell death, and TNF-α played an essential role in this effect. The ADL extract reduced LPS-treated THP-1 cell-conditioned medium-induced trophoblast cell death by inhibiting MAPKs and the NF-κB pathway in macrophages. ADL extract prevented exogenous TNF-α-induced increased trophoblast cell death and decreased cell viability. Conclusions: We have demonstrated that the inhibition of LPS-induced inflammation by ADL extract can prevent preterm birth, fetal loss, and fetal growth restriction.

In this study, the torsional vibration analysis for a marine propulsion system is carried out by us-ing the transfer matrix method(TMM). The torsional moment produced by gas pressure and recip-rocating inertia force may yield severe torsional vibration problem in the shaft system which results in a damage of engine system. There are several ways to control the torsional vibration problem at hand, firstly natural frequencies can be changed by adjusting shaft dimensions and/or inertia quanti-ties, secondly firing order and crank arrangement are modified to reduce excitation force, and finally lower the vibration energy by adopting torsional vibration damper. In this paper, the viscous torsional vibration damper is used for reducing the torsional vibration stresses of shaft system and it is con-formed that optimum model of the viscous damper can be determined by selecting the geometric de-sign parameters of damper and silicon oil viscosity. * 기 호 설 명   : 조화하중의 진폭 토크(N-m) : 엔진 회전수(rpm)

In this paper, a series of algorithms are proposed for controlling different kinds of multimedia contents and realizing interact between human and computer by using single input device. Human gesture recognition based on NUI is presented firstly in my paper. Since the image information we get it from camera is not sensitive for further processing, we transform it to YCbCr color space, and then morphological processing algorithm is used to delete unuseful noise. Boundary Energy and depth information is extracted for hand detection. After we receive the image of hand detection, PCA algorithm is used to recognize hand posture, difference image and moment method are used to detect hand centroid and extract trajectory of hand movement. 8 direction codes are defined for quantifying gesture trajectory, so the symbol value will be affirmed. Furthermore, HMM algorithm is used for hand gesture recognition based on the symbol value. According to series of methods we presented, we can control multimedia contents by using human gesture recognition. Through large numbers of experiments, the algorithms we presented have satisfying performance, hand detection rate is up to 94.25%, gesture recognition rate exceed 92.6%, hand posture recognition rate can achieve 85.86%, and face detection rate is up to 89.58%. According to these experiment results, we can control many kinds of multimedia contents on computer effectively, such as video player, MP3, e-book and so on.

In this paper free vibration analysis of symmetric and cross-ply elastic laminated shells based on FSDT was performed through discretization of equations of motion and boundary condition. Structural model of laminated composite cylindrical shells subjected to a combination of magnetic and thermal fields is developed via Hamilton’s variational principle. These coupled equations of motion are based on the electromagnetic equations(Faraday, Ampere, Ohm, and Lorenz equations) and thermal equa-tions which are involved in constitutive equations. Variations of dynamic characteristics of composite shells with applied magnetic field, temperature gradient, and stacking sequence are investigated and pertinent conclusions are derived. * 기 호 설 명 B : 자속밀도 벡터    : 중립축에 대한 회전각 E : 전계 벡터 f : 로렌츠 힘 벡터 H : 자계 벡터 h : 원통셸의 두께 J : 전류밀도 벡터 †교신저자; 정회원, 충남대학교, 기계공학과E-mail : songos@cnu.ac.krTel : (042)821-5650, Fax : (042)822-5642* 정회원, 충남대학교 대학원** 정회원, 한국원자력연구원*** 정회원, 특허청# 이 논문의 일부는 2012년 춘계 소음진동 학술대회에서 발표되었음.

Structural model of laminated composite plates based on the first order shear deformable plate theory and subjected to a combination of magnetic and thermal fields is developed. Coupled equations of motion are derived via Hamilton`s principle on the basis of electromagnetic equations (Faraday, Ampere, Ohm, and Lorentz equations) and thermal ones which are involved in constitutive equations. In order to reveal the implications of a number of geometrical and physical features of the model, free vibration of a composite plate immersed in a transversal magnetic field and subjected to a temperature gradient is considered. Special coupling effects between the magnetic-thermal-elastic fields are revealed in this paper.

In this paper, we will present a method to detect human hand and recognize hand gesture. For detecting the hand region, we use the feature of human skin color and hand feature (with boundary complexity) to detect the hand region from the input image; and use algorithm of optical flow to track the hand movement. Hand gesture recognition is composed of two parts: 1. Posture recognition and 2. Motion recognition, for describing the hand posture feature, we employ the Fourier descriptor method because it's rotation in variant. And we employ PCA method to extract the feature among gesture frames sequences. The HMM method will finally be used to recognize these feature to make a final decision of a hand gesture. Through the experiment, we can see that our proposed method can achieve 99% recognition rate at environment with simple background and no face region together, and reduce to 89.5% at the environment with complex background and with face region. These results can illustrate that the proposed algorithm can be applied as a production.

The aim of this paper is to present the methodology for hand tracking and hand gesture recognition. The detected hand and gesture can be used to implement the non-contact mouse. We had developed a MP3 player using this technology controlling the computer in stead of mouse. In this algorithm, we first do a pre-processing to every frame which including Lighting compensation and background filtration to reducing the adverse impact on correctness of hand tracking and hand gesture recognition. Secondly, YCbCr skin-color likelihood algorithm is used to detecting the hand area. Then, we used Continuously Adaptive Mean Shift (CAMSHIFT) algorithm to tracking hand. As the formula-based region of interest is square, the hand is closer to rectangular. We have improved the formula of the search window to get a much suitable search window for hand. And then, Support Vector Machines (SVM) algorithm is used for hand gesture recognition. For training the system, we collected 1500 hand gesture pictures of 5 hand gestures. Finally we have performed extensive experiment on a Windows XP system to evaluate the efficiency of the proposed scheme. The hand tracking correct rate is 96% and the hand gestures average correct rate is 95%.

Research Institute of Pharmaceutical Sciences, College of Pharmacy, Kyungpook National University, Daegu 702-701, Korea *E-mail: dhna@knu.ac.kr (D.H. Na); kssong@knu.ac.kr (K.-S. Song) Natural Products Department, Korea Promotion Institute for Traditional Medicine Industry, Gyeongbuk 712-260, Korea College of Pharmacy, Catholic University of Daegu, Gyeongbuk 712-702, Korea Received December 26, 2013, Accepted March 28, 2014

본 연구에서는 모자반목 모자반과 갈조류인 괭생이 모자반의 3가지 서로 다른 추출물의 면역활성 가능성을 비교연구하기 위하여 RWA264.7 대식세포에 서로 다른 괭생이 모자반 추출물을 처리하여 $TNF-{\alpha}$ , IL-6 및 NO 분비능과 MAPK 신호전달경로 및 $NF-{\kappa}B$ 활성화 수준을 측정하였다. 괭생이 모자반 ...

Standard procedures for a fracture toughness testing require very severe restrictions for the specimen geometry to eliminate a size effect on the measured properties. Therefore, the used standard fracture toughness data results in the integrity assessment being irrationally conservative. However, a realistic fracture in general structures, such as in nuclear power plants, may develop under the low constraint condition of a large scale yielding with a shallow surface crack. In this paper, cleavage fracture toughness tests have been made on side-grooved PCVN (precracked charpy V-notch) type specimens (10 by 10 by 55 mm) with various crack depths. The constraint effects on the crack depth ratios were evaluated quantitatively by the developed scaling method using the 3-D finite element method. After the fracture toughness correction from scaling model, the statistical size effects were also corrected according to the standard ASTM E 1921 procedure. The results were evaluated through a comparison with the T0 of the standard CT specimen. The corrected T0 for all of the PCVN specimens showed a good agreement to within 5.4℃ regardless of the crack depth, while the averaged PCVN T0 was 13.4℃ higher than the real CT test results.

Finite element alternating method has been suggested and used effectively to obtain the fracture parameters in assessing the integrity of cracked structures. The method obtains the solution from alternating independently between the FEM solution for an uncracked body and the crack solution in an infinite body. In the paper, the finite element alternating method is extended in order to obtain the elastic-plastic stress fields of a three dimensional inner crack. The three dimensional crack solutions for an infinite body were obtained using symmetric Galerkin boundary element method. As an example of a three dimensional inner crack, a penny-shaped crack in a finite body was analyzed and the obtained elastc-plastic stress fields were compared with the solution obtained from the finite element analysis with fine mesh. It is noted that in the region ahead of the crack front the stress values from FEAM are close to the values from FEM. But large discrepancy between two values is observed near the crack surfaces.

The finite element alternating method (FEAM) was extended to obtain fracture mechanics parameters and elasto-plastic stress fields for 3-D inner cracks. For solving a problem of a 3-D finite body with cracks, the FEAM alternates independently the finite element method (FEM) solution for the uncracked body and the solution for the crack in an infinite body. As the required solution for a crack in an infinite body, the symmetric Galerkin boundary element method formulated by Li and Mear was used. For elasto-plastic numerical analysis, the initial stress method proposed by Zienkiewicz and co-workers and the iteration procedure proposed by Nikishkov and Atluri were used after modification. The extended FEAM was examined through comparing with the results of commercial FEM program for several example 3-D crack problems.

This paper investigates the impact of stock option of board of directors on Corporate Social Responsibility (CSR) activities using 336 of Korean firms in 2013. Stock options are the most typical form of long-term incentive compensation and are contingent on the value of the stock in the future. We develop and analyze hypothesis, based on stakeholder theory. We find a significant relationship between the stock option and CSR activities, after controlling for various firm characteristics. Our findings are that long-term compensation for executives is positively associated with CSR activities and it attempts to focus executives’ efforts on optimizing the longer term. It also implies that the structure of executive compensation could be used as an effective tool to encourage management to undertake socially responsible actions, therefore resulting in more socially responsible firms.

The finite element alternating method based on the superposition principle has been known as an effective method to obtain the stress intensity factors for general multiple collinear or curvilinear cracks in an isotropic plate. In this paper the method is extended further to solve two-dimensional cracks embedded in a bimaterial plate. The main advantage of this method is that it is not necessary to make crack meshes considering the stress singularity at the crack tip. The solution of the developed code is obtained from an iteration procedure, which alternates independently between the finite element method solution for an uncracked body and the analytical solution for cracks in an infinite body. In order to check the validity of the method, several crack problems of a bimaterial body are solved and compared with the results obtained from the finite element analysis.

The performance of the advanced Zr alloys (HANA) for a high bum-up fuel has been evaluated in the out-of-pile and in-pile conditions. The corrosion resistance of the HANA claddings was superior to Zicaloy-4 in a PWR-simulating loop condition. The improved corrosion resistance of the HANA claddings was attributed to the fine distribution of the precipitate. HANA claddings showed a higher creep resistance as compared to Zircaloy-4 from the thermal creep test. The deformation behavior of HANA in a LOCA condition was similar to Zircaloy-4. Threshold ECR value of HANA was higher than the conventional value of 17% in Zircaloy-4, which is mainly due to the fact that the Nb decreases the oxidation rate as well as the hydrogen pickup. Fretting wear test revealed that HANA claddings have a similar wear resistance to Zircaloy-4. From the irradiation test up to burn-up of about 12 GWd/MtU, HANA claddings showed a better corrosion resistance as well as a better creep resistance than Zircaloy-4. The in-pile corrosion resistance of the HANA claddings was improved by 40-50% as compared to Zircaloy-4 on the basis of the oxide thickness measurements.

In order to simulate the growth of arbitrarily shaped three dimensional cracks, the finite element alternating method is extended. As the required analytical solution for a crack in an infinite body, the symmetric Galerkin boundary element method formulated by Li and Mear is used. In the study, a crack is modeled as distribution of displacement discontinuities, and the governing equation is formulated as singularity-reduced integral equations. With the proposed method several example problems for three dimensional cracks in an infinite solid, as well as their growth under fatigue, are solved and the accuracy and efficiency of the method are demonstrated.

Poly(l-lactide)/poly(butylene succinate) microcapsules containing an aqueous solution of sodium(+)-tartrate dihydrate were prepared by the interfacial precipitation method through solvent evaporation from (w/o)/w emulsion. The effects of poly(vinyl alcohol) used as a protective colloid in the microencapsulation were investigated regarding thermal properties, particle size distributions, surface morphologies, and release behaviors of the biodegradable microcapsules. It was concluded that encapsulation efficiency, surface morphologies, thermal properties, and releasing speed were closely related to the particle size distributions of microcapsules under different conditions of the protective colloid.

For integrity assessment of structure containing crack, evaluation method based on fracture mechanics such as linear-elastic and elastic-plastic fracture mechanics has been relatively common method and becoming more widespread. However, it can be used only if the crack opening or tearing is occurred. If the crack exists on the piping components subjected to internal pressure, net-section stress is occurred in the direction on crack opening no matter where crack locate. On the contrary to this, if the external pressure is applied to piping components, net-section stress is occurred opposite direction and it is expected crack opening not to be occur. The subject of this study is SMART steam generator tube which is designed as helical geometrical feature and to be pressurized outside. Three dimensional finite element analyses are carried out to investigate crack behavior under external pressure considered various crack geometries and locations. Furthermore, the possibility of failure of SMART steam generator tube under design pressure is investigated.Copyright © 2011 by ASME

The radioactivity of 3H of the metal samples from the nuclear sites was analyzed by using a commercialized high temperature furnace and a Liquid Scintillation Counter (LSC). The 3H activity of the sample was measured according to the duration of the high temperature combustion and the oxidation temperature. Basically, the recovery from the furnace was 90% for 3H and the LSC had a quenching efficiency of approximately 30 %. HNO3 was used as a trapping solution for 3H and the solution was cocktailed with a scintillator. The activity extracted from the sample was increased till the combustion time elapsed 60 minutes and the increasing rate was reduced continuously thereafter at 600 °C whereas 80% of radioactivity was extracted during the first 15 minutes at 900 °C. Also, the pretreatment for the metal sample, which included a high temperature combustion and trapping, had the time required of at least four hours at 900 °C. Finally, it was suggested that this high temperature combustion method could be applied to analyze the activity of the radioactive metal waste from the nuclear power plants.

Melt blends of polyethylene(PE)/nylon-6(nylon), PE/nylon/(maleic anhydride-g-polyethylene) (g-PE) and g-PE/nylon were prepared using a Brabender Plasticorder. Measured properties included steady shear viscosities from a capillary rheometer, thermal properties from DSC and morphologies from SEM. It was found that g-PE is an effective compatibilizer for the PE/nylon blends, especially in PE-rich compositions. Compatibility was greatly improved in g-PE/nylon blends from morphological and rheological points of view, and the results were interpreted in terms of possible chemical reactions between g-PE and nylon.

Although many information hiding paradigm provides many advantages for protect important information, we try to introduce new method in concealing thing. One of these is Steganography Many efforts have been made to encrypt data as well as to hide data. Most users wish not to lose the data that they want to hide. The steganography is one of methods that users can hide data. Some steganography softwares use audio data among multimedia data. However, the commercialized audio steganography softwares have disadvantages that the existence of hidden messages can be easily recognized visually and only certain-sized data can be hidden. To solve these problems, this study suggested, designed and implemented the Dynamic Message Embedding (DME) algorithm. Also, to improve the security level of the secret message, the file encryption algorithm has been applied. Through the DME algorithm and the file encryption algorithm, StegoWaveK system that performs audio steganography was designed and implemented. Then, the suggested system and the commercialized audio steganography system were compared and analyzed on some criteria.

The anticipated increase in mobility and popular use of mobile services will require more technologies for authenticating mobile hosts and protecting their privacy. However, issues such as privacy and confidentiality in mobile computing environments and the resource restriction of mobile hosts have not been given enough consideration. In this paper, we present an authentication protocol that provides mobile hosts with the functionalities of authentication and session key distribution for user privacy and secure communication. Considering mobile computing environments, our protocol has design principles such as reducing computation and communication overhead of mobile hosts, and uses random numbers, time-stamps, and authentication codes in order to protect systems from attacks by eavesdroppers. While our protocol supports authentication, secure communication, anonymity, and untraceability for mobile hosts, it can be an efficient authentication protocol for mobile computing environments.

As multimedia services in mobile computing environments are growing today, more investigations on multicasting for mobile computing environments are in progress. When the multicasting is performed on wireless networks, some serious problems, that do not occur in the traditional fixed networks, can occur. One problem is that, when a mobile host (MH) enters a new cell, if there is no member belonging to the same multicast group as the mobile host in the new cell, the mobile support station (MSS) of the new cell must join the multicast group. In this process, the MH may encounter the group join delays and the graft delays. Also, the frequent acknowledgements and the packet retransmissions caused by the transmission media with low bandwidth and high error rate can generate some extra heavy traffic. This paper presents a prejoin method that lets the new MSS join the multicast group ahead for reducing the join delay and the graft delay. Additionally, we propose a multi-level ACKs strategy that separately confirms the ACKs exchanged between a data sender and a MSS and between a MSS and a MH. It is shown that our scheme shows more performance improvements as more adjacent cells have not joined the multicast group and each MH has lower mobility rate.

In wireless ad-hoc network environments, packet retransmissions and route reconstructions caused by link failures can be more frequent than in the wired network environments. Therefore, new multicasting scheme reducing transmission delays and packet losses due to link changes of a multicast tree is required. In this paper, we propose a RAMRP (Reliable Ad-hoc Multicast Routing Protocol) protocol. It supports a reliable multicasting suitable for wireless ad-hoc networks by reducing the number of route reconstructions and packet retransmissions.

In mobile computing environment, mobile support station provides a wireless communication link to mobile clients and help them to access remote file servers that reside on a fixed network. Mobile hosts send requests to the mobile support station to access files on remote file servers. No longer this environment requires a user to stay at a fixed position in the network and enables almost unrestricted user mobility. The user mobility affects the file access latency. Mobile hosts have severe resource constraints in terms of limited size of non-volatile storage, and the burden of computation and communication load raises file access latency. In this paper, we propose a scheme for reducing the file access latency by using file migration scheme. We develope an on-demand file migration scheme which determines when the file server should migrate files to another server, and when it should transfer files to mobile hosts. Using simulation, we examine the effects of the parameters such as file access frequency, file size, and mobility rate on the file system performance. We present simulation results, providing useful insight into file system latency.