• 제목/요약/키워드: Joint Energy

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Enhanced Transdermal Delivery of Pranoprofen from the Bioadhesive Gels

  • Shin, Sang-Chul;Cho, Cheong-Weon
    • Archives of Pharmacal Research
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    • v.29 no.10
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    • pp.928-933
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    • 2006
  • Percutaneous delivery of NSAIDs has advantages of avoiding hepatic first pass effect and delivering the drug for extended period of time at a sustained, concentrated level at the inflammation site that mainly acts at the joint and the related regions. To develop the new topical formulations of pranoprofen that have suitable bioadhesion, the gel was formulated using hydroxypropyl methylcellulose (HPMC) and poloxamer 407. The effects of temperature on drug release was performed at $32^{\circ}C$, $37^{\circ}C$ and $42^{\circ}C$ according to drug concentration of 0.04%, 0.08%, 0.12%, 0.16%, and 0.2% (w/w) using synthetic cellulose membrane at $37{\pm}0.5^{\circ}C$. The increase of temperature showed the increased drug release. The activation energy (Ea), which were calculated from the slope of lop P versus 1000/T plots was 11.22 kcal/ mol for 0.04%, 10.79 kcal/mol for 0.08%, 10.41 kcal/mol for 0.12% and 8.88 kcal/mol for 0.16% loading dose from the pranoprofen gel. To increase the drug permeation, some kinds of penetration enhancers such as the ethylene glycols, the propylene glycols, the glycerides, the non-ionic surfactants and the fatty acids were incorporated in the gel formulation. Among the various enhancers used, propylene glycol mono laurate showed the highest enhancing effects with the enhancement factor of 2.74. The results of this study suggest that development of topical gel formulation of pranoprofen containing an enhancer is feasible.

An Experimental Study on Comparison of Structural Behavior of PT Flat Plate and RC Flat Plate Interior Connections (PT 플랫 플레이트와 RC 플랫 플레이트 내부 접합부의 구조적 거동 비교에 관한 실험적 연구)

  • Lee Dong Keun;Ha Sang-Su;Han Sang Whan;Lee Li Ryung
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.05a
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    • pp.111-114
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    • 2005
  • While the existing reinforced concrete flat plate(RC flat plate) has a lot of advantages including reduced building height, it has some weak points such as many steel bars and the brittle rupture by punching shear. Compared with the RC flat plate, the post-tensioned flat plate (PT flat plate) has not only the same merits, but it also makes longer span possible and induces slab-column connections to be failed with the ductile behavior rather than with the brittle behavior by means of post-tensioning. However, it is difficult to define the joint behavior of PT flat plate under vertical and lateral loads since there are limit experimental results. For this reason, the experimental study is undertaken to investigate the comparison of behavior of PT flat plate and RC flat plate, and how flat plate(Gravity Load Resisting System) is displaced as lateral loads, like the wind and the earthquake, are occur. The result of this experiment shows that PT flat plate is generally superior to RC flat plate in terms of controlling crack, postponing stiffness deterioration, energy dissipation, etc.

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Experimental Cyclic Behavior of Precast Hybrid Beam-Column Connections with Welded Components

  • Girgin, Sadik Can;Misir, Ibrahim Serkan;Kahraman, Serap
    • International Journal of Concrete Structures and Materials
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    • v.11 no.2
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    • pp.229-245
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    • 2017
  • Post-earthquake observations revealed that seismic performance of beam-column connections in precast concrete structures affect the overall response extensively. Seismic design of precast reinforced concrete structures requires improved beam-column connections to transfer reversed load effects between structural elements. In Turkey, hybrid beam-column connections with welded components have been applied extensively in precast concrete industry for decades. Beam bottom longitudinal rebars are welded to beam end plates while top longitudinal rebars are placed to designated gaps in joint panels before casting of topping concrete in this type of connections. The paper presents the major findings of an experimental test programme including one monolithic and five precast hybrid half scale specimens representing interior beam-column connections of a moment frame of high ductility level. The required welding area between beam bottom longitudinal rebars and beam-end plates were calculated based on welding coefficients considered as a test parameter. It is observed that the maximum strain developed in the beam bottom flexural reinforcement plays an important role in the overall behavior of the connections. Two additional specimens which include unbonded lengths on the longitudinal rebars to reduce that strain demands were also tested. Strength, stiffness and energy dissipation characteristics of test specimens were investigated with respect to test variables. Seismic performances of test specimens were evaluated by obtaining damage indices.

Estimating of water pressure to avoid hydraulic fracturing in water pressure test

  • Amnieh, Hassan Bakhshandeh;Masoudi, Majid
    • Computers and Concrete
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    • v.19 no.2
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    • pp.171-177
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    • 2017
  • Water pressure test operation is used before the grouting to determine the rate of penetrability, the necessity and estimations related to grouting, by the penetration of water into the borehole. One of the parameters which have the highest effect is pressure of water penetration since the application of excessive pressure causes the hydraulic fracture to occur in the rock mass, and on the other hand, it must not be so small that prevents from seeing mechanical weaknesses and the rate of permeability. Mathematical modeling is used for the first time in this study to determine the optimum pressure. Thus, the joints that exist in the rock mass are simulated using cylindrical shell model. The joint surroundings are also modeled through Pasternak environment. To obtain equations governing the joints and the surroundings, energy method is used accompanied by Hamilton principle and an analytical solution method is used to obtain the maximum pressure. In order to validate the modeling, the pressure values obtained by the model were used in the sites of Seymareh and Aghbolagh dams and the relative error rates were measured considering the differences between calculated and actual pressures. Modeling in the sections of Seymareh dam showed 4.75, 3.93, 4.8 percent error rates and in the sections of Aghbolagh dam it rendered the values of 22.43, 5.22, 2.6 percent. The results indicate that this modeling can be used to estimate the amount of pressure for hydraulic fracture in water pressure test, to predict it and to prevent it.

Introducing a new all steel accordion force limiting device for space structures

  • Poursharifi, Maryam;Abedi, Karim;Chenaghlou, Mohammadreza;Fleischman, Robert B.
    • Structural Engineering and Mechanics
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    • v.74 no.1
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    • pp.69-82
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    • 2020
  • A significant defect of space structures is the progressive collapse issue which may restrict their applicability. Force limiting devices (FLDs) have been designed to overcome this deficiency, though they don't operate efficiently in controlling the force displacement characteristics. To overcome this flaw, a new type of FLD is introduced in the present study. The "all steel accordion force limiting device" (AFLD) which consists of three main parts including cylindrical accordion solid core, tubular encasing and joint system is constructed and its behavior has been studied experimentally. To improve AFLD's behavior, Finite element analysis has been carried out by developing models in ABAQUS software. A comprehensive parametric study is done by considering the effective design parameters such as core material, accordion wave length and accordion inner diameter. From the results, it is found that AFLD can obtain a perfect control on the force-displacement characteristics as well as attaining the elastic-perfect plastic behavior. Obtaining higher levels of ultimate load carrying capacity, dissipated energy and ductility ratio can be encountered as the main privileges of this device. Ease of construction and erection are found to be further advantages of AFLD. Based on the obtained results, a procedure for predicting AFLD's behavior is offered.

Experimental Investigation of The Lateral Retrofitting Effect of FRP Sheet and Buckling-restrained Braces for Beam-Column Joints (FRP Sheet와 비좌굴 가새를 적용한 보-기둥 접합부의 횡방향 보강효과에 관한 실험적 연구)

  • Byon, Eun-Hyuk;Kim, Min-Sook;Lee, Young-Hak;Kim, Hee-Cheul
    • Journal of the Earthquake Engineering Society of Korea
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    • v.15 no.1
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    • pp.49-56
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    • 2011
  • The strengthening effect of CFRP sheet and AFRP sheet with buckling-restrained brace for Beam-Column joints under constant axial and cyclic lateral loading is evaluated experimentally in this paper. Six test specimens were constructed. The main test parameters included the FRP Sheet and Buckling-restrained braces. The results of the tests were analyzed by focusing on their mode of failure, maximum load, ductility indexes, and energy dissipation capacity. Test results indicated that CFRP Sheet with the buckling-restrained brace system significantly increased the strength and stiffness of the specimen and that it was the most adequate retrofitting method.

Process and Strength Evaluation of Mechanical Press Joining (기계적 프레스 접합의 공정 및 강도 평가)

  • Lee, Sang-Hoon;Kim, Ho-Kyung
    • Journal of the Korean Society of Safety
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    • v.26 no.4
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    • pp.1-6
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    • 2011
  • New methods for joining sheet of metal are being sought. One of the most promising methods is MPJ (mechanical press joining). It has been used in thin metal work because of its simple process and relative advantages over other methods, as it requires no fasteners such as bolts or rivets, consumes less energy than welding, and produces less ecological problems than adhesive methods. In this study, the joining process and static behavior of single overlap joints has been investigated. During fixed die type joining process for SPCC plates, the optimal applied punching force was found. The maximum tensile-shear strength of the specimen produced at the optimal punching force was 1.75 kN. The FEM analysis result on the tensile-shear specimen showed the maximum von-Mises stress of 373 MPa under the applied load of 1.7 kN, which is very close to the maximum tensile strength of the SPCC sheet(= 382 MPa). This suggests that the FEM analysis is capable of predicting the maximum tensile load of the joint.

Commercialization of Genetically Modified Ornamental Plants

  • Chandler Stephen F.
    • Journal of Plant Biotechnology
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    • v.5 no.2
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    • pp.69-77
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    • 2003
  • The ornamental industry encompasses cut flower, pot plant, turfgrass and nursery stock production and is an important part of the agricultural sector. As internationally traded commodities, cut flowers and plants are an integral part of the economy of a number of developing countries in South America, the Caribbean and Africa. Genetic modification (GM) is a tool with great potential to the ornamental horticulture industry. The rapid progress in our knowledge of plant molecular biology can accelerate the breeding ornamental plants using recombinant DNA technology techniques. Not only is there the possibility of creating new, novel products the driver of the industry but also the potential to develop varieties requiring less chemical and energy inputs. As an important non-food agricultural sector the use of genetically modified (GM) ornamental crops may also be ideal for the intensive farming necessary to generate pharmaceuticals and other useful products in GM plants. To date, there are only a few ornamental GM products in development and only one, a carnation genetically modified for flower colour, in the marketplace. International Flower Developments, a joint venture between Florigene Ltd. in Australia and Suntory Ltd. of Japan, developed the GM carnations. These flowers are currently on sale in USA, Japan and Australia. The research, development and commercialization of these products are summarized. The long term prospects for ornamental GM products, like food crops, will be determined by the regulatory environment, and the acceptance of GM products in the marketplace. These critical factors will be analysed in the context of the current legislative environment, and likely public and industry opinion towards ornamental genetically modified organisms (GMO's).

Resource Allocation in Multi-User MIMO-OFDM Systems with Double-objective Optimization

  • Chen, Yuqing;Li, Xiaoyan;Sun, Xixia;Su, Pan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.5
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    • pp.2063-2081
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    • 2018
  • A resource allocation algorithm is proposed in this paper to simultaneously minimize the total system power consumption and maximize the system throughput for the downlink of multi-user multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) systems. With the Lagrange dual decomposition method, we transform the original problem to its convex dual problem and prove that the duality gap between the two problems is zero, which means the optimal solution of the original problem can be obtained by solving its dual problem. Then, we use convex optimization method to solve the dual problem and utilize bisection method to obtain the optimal dual variable. The numerical results show that the proposed algorithm is superior to traditional single-objective optimization method in both the system throughput and the system energy consumption.

Visualization and classification of hidden defects in triplex composites used in LNG carriers by active thermography

  • Hwang, Soonkyu;Jeon, Ikgeun;Han, Gayoung;Sohn, Hoon;Yun, Wonjun
    • Smart Structures and Systems
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    • v.24 no.6
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    • pp.803-812
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    • 2019
  • Triplex composite is an epoxy-bonded joint structure, which constitutes the secondary barrier in a liquefied natural gas (LNG) carrier. Defects in the triplex composite weaken its shear strength and may cause leakage of the LNG, thus compromising the structural integrity of the LNG carrier. This paper proposes an autonomous triplex composite inspection (ATCI) system for visualizing and classifying hidden defects in the triplex composite installed inside an LNG carrier. First, heat energy is generated on the surface of the triplex composite using halogen lamps, and the corresponding heat response is measured by an infrared (IR) camera. Next, the region of interest (ROI) is traced and noise components are removed to minimize false indications of defects. After a defect is identified, it is classified as internal void or uncured adhesive and its size and shape are quantified and visualized, respectively. The proposed ATCI system allows the fully automated and contactless detection, classification, and quantification of hidden defects inside the triplex composite. The effectiveness of the proposed ATCI system is validated using the data obtained from actual triplex composite installed in an LNG carrier membrane system.