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The purpose of this study was to examine how journalists judge and react to the withholding of information by the government during a national crisis. This article analyses the case of the sinking of the Cheonan, which killed four South Korean marines and sparked extreme tension throughout the Korean peninsula. For this research, in‐depth interviews were conducted with journalists who reported on the Cheonan incident. All participants (11 journalists) believed that the South Korean government withheld information about the cause of the Cheonan sinking for a period of time. Half of the journalists did not agree with the governmental restrictive information policy, while the other half accepted this as the government acting in the best interest of national security in a crisis situation.

As generation of Web 2.0 comes in, enormous information of corporation from various platform are being produced. However, corporations should understand features of each platform and appropriate strategies in order to attract the public in the midst of such flood of information. Numerous studies have been conducted regarding SNS which has grown rapidly in recent but a study relating a specific medium is relatively in short. So this study analyzed how information of Instagram bulletin board is accepted in perspective of consumer in Korean and America, We examined the relationship between intention of acceptance and Word Of Mouth effect through meditating effect of information usefulness. To answer the research question, we conducted online survey with Korean and USA college students. The result showed that usefulness of the information was shown to the major intermediary variable between the information characteristics of bulletin board and the intention of acceptance intention and Word Of Mouth(WOM).

This paper presents a velocity-synchronizing control for the multiple axes of an injection unit; based on MBS, a virtual design model has been developed for the multiple-axes servomechanism. Prior to the design of the controller, a linear plant model was derived via open- loop response simulations. To synchronize the motions of the multiple axes, a cross-type synchronizing controller was designed and combined with the PID control to accommodate any parameter mismatches among the multiple axes. From the tracking control simulations, a significant reduction of both velocity-tracking and position-tracking errors was achieved through the use of the proposed control scheme.

Bed Activity Monitoring System (BAMS) monitors and assess the mobility of people on a bed. This is a useful and critical application for patients with mobility issues after stroke or traumatic brain injury. The system is based on processing of data collected from a piezoelectric pressure sensor for discriminating mobility patterns. There are four different types of motion that were simulated by non-patient volunteers and data was collected. In this paper, two methods were used to extract feature parameters (autoregressive and cepstral coefficients) from the acquired data. Two classification algorithms, Euclidean Distance Measure (EDM) and Weighted Distance Measure (WDM) were used to classify and discriminate the mobility patterns of normal person (healthy subject) from people with mobility issues (patient subjects). Experimental result shows that the recognition rate using cepstral parameters was more effective compare to autoregressive parameters.

This paper focuses on the issue of force synchronizing control for the injection servomechanism of injection molding machines. Prior to the controller design, a virtual design model was developed for the injection mechanism with an AC servomotor-ball screw. A synchronizing controller is designed and combined with the PID control to accommodate the mismatches between the real plant and the linear model plant used. Due to the plant uncertainty, the stiffness and the damping of the mechanism were considered. From the tracking control simulations based on the virtual design model, it is shown that a significant reduction in force synchronizing error is achieved through the use of a proposed control scheme.

This paper deals with the issue of defining friction characteristics of a multi-chamber cylinder for digital hydraulics. Using a multi-chamber cylinder under a set of supply pressures, friction characteristics are experimentally investigated for a range of velocity according to load conditions. A binary digit-based pressure e.g., high pressure or low pressure has been applied to each chamber. The friction force is measured based on the equation of motion using measured values of the pressures in the chambers of the multi-chamber cylinder and the position of the piston. As a mechanism to load the multi-chamber cylinder, a 1-Degree of Freedom (DOF) boom mockup mimicking a medium-sized mobile machine boom has been constructed. Then it has been utilized to test the motion of the cylinder under different mass–load conditions. It is shown that the cylinder states do not dominantly affect the friction force of a multi-chamber cylinder, comparing the effect of other parameter such as mass load and velocity, which is expected to be useful for the secondary control of digital hydraulic systems.

This paper deals with the issue of force synchronizing control for the clamping servomechanism of injection molding machines. Prior to the controller design, a virtual design model has been developed for the clamping mechanism with hydraulic systems. Then, a synchronizing controller is designed and combined with an adaptive feedforward control in order to accommodate the mismatches between the real plant and the linear model plant used. As a disturbance, the leakage due to the ring gap with relative motion in the cylinder has been introduced. From the robust force tracking simulations, it is shown that a significant reduction in the force synchronizing error is achieved through the use of a proposed control scheme. * Corresponding author: shcho@hongik.ac.kr 1 Department of Mechanical and System Design Engineering, Hongik University, Seoul 121-791, Korea Copyright C 2014, KSFC This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License(http:// creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 기호 설명 ( 1~4) fsi i e  : tracking error signal ( 1~4) pi i e  : synchronizing error signal r f : reference input force ( 1~4) i i f  : output clamping force ( 1~4) ai i K  : proportional gain  : synchronizing gain  : adaptive feedforward gain n  : natural frequency n  : damping ratio 1. 서 론 유압시스템은 단위 중량당 동력비가 높고, 고응답 성과 고강성으로 인하여 현대 산업에서 중요한 액추 에이터이다. 최근 유압액추에이터의 위치 또는 힘의 제어에 대한 연구는 많은 관심을 끌고 있다. 힘 또 는 압력의 추적제어는 방진과 차량 능동현가장치와 같은 용도에서 매우 중요하다. 본 연구에서는 직압식 사출성형기의 클램핑 공정을 대상으로 4축 구동 실린 더 시스템의 힘 동기제어를 다룬다. 다수의 구동축을 갖는 생산시스템에서, 제품 정밀도 혹은 생산효율을 향상시키기 위해서는 정상상태와 과도상태에서 구동 축간의 동기화를 도모할 필요가 있다. 부하변동 등 에 의한 과도상태에서 동기화를 실현하기 위해서는, 각축의 출력은 목표 궤도에 추종하는 것에 우선하여, 먼저 축 간의 동기화를 실현하고 목표 궤도에 추종하 도록 제어되어야 한다. 기본적인 다축 시스템의 동기 화 방법으로서 한 쪽을 주축으로 하고 그 외의 축을 추종축으로 하는 마스터 슬레이브(Master Slave) 방 법이 고려되고 있다. 그러나 구동축의 동특성도 동작 조건에 의하여 임의 범위에서 변동하므로 각축을 동 4축 구동 유압실린더-클램핑 부하 시스템의 힘 동기제어 10 유공압건설기계학회지 2014. 6 Fig. 1 3D CAD model for 4 axes system 등하게 취급하는 방식이 바람직하다. 고정게인(Gain) 제어기는 동특성의 변동에 대처할 수 없으므로 적응 기능을 갖는 제어기가 필요하다. 이를 위하여 응답성 의 개선과 외란보상에 유효한 적응 피드포워드 제어 기(이하 AFC; Adaptive Feedforward Control)를 4축 구동 시스템에 적용하는 문제를 고찰한다. AFC를 이 용한 시스템에 동기오차를 도입하여, 추적오차 뿐만 아니라 동기오차도 영에 수렴시킴으로서 과도상태와 정상상태에서의 동기화를 도모한다. 본 연구에서는 클램핑 메카니즘의 기하학적 정보를 상용소프트웨어 SimulationX에 내장된 다-물체 시스템(이하 MBS ; Multi-Body System)기법을 활용하여 3D CAD모델 링 한다. 그리고 멀티-도메인(Multi-Domain) 시뮬레 이션을 통하여 버추얼 디자인(Virtual Design) 모델 을 구축한다.

This paper deals with the issue of virtual design of a motor-toggle servomechanism for injection-molding machines. Based on the 3D CAD of multi-body system, a five-point-type toggle mechanism has been developed with clamping force build-up. Prior to controller design, open-loop responses are obtained to derive a transfer function. In order to accommodate mismatches between the real plant and the linear model used, a discrete-time sliding function is defined and combined with PID control. The uncertainty in the mass of moving platen and the Coulomb friction at pin joints are considered for robust motion control applications. Through the use of proposed control scheme, not only significant reduction in position error at moving platen but also clamping force build-up is achieved appropriately.

In this paper, we propose an efficient dynamic workload balancing strategy which improves the performance of high-performance computing system. The key idea of this dynamic workload balancing strategy is to minimize execution time of each job and to maximize the system throughput by effectively using system resource such as CPU, memory. Also, this strategy dynamically allocates job by considering demanded memory size of executing job and workload status of each node. If an overload node occurs due to allocated job, the proposed scheme migrates job, executing in overload nodes, to another free nodes and reduces the waiting time and execution ∙제1저자 : 조승호 ∙교신저자 : 조승호 ∙투고일 : 2014. 1. 22., 심사일 : 2014. 2. 3, 게재확정일 : 2014. 2. 6. * 강남대학교 컴퓨터미디어정보공학부(Division of Computer and Media Information Engineering, Kangnam University) * 이 논문은 강남대학교 교내연구비 지원을 받아 연구된 것임 40 Journal of The Korea Society of Computer and Information February 2014 time of job by balancing workload of each node. Through simulation, we show that the proposed dynamic workload balancing strategy based on CPU, memory improves the performance of high-performance computing system compared to previous strategies. ▸

This paper presents a synchronizing adaptive feedforward control for clamping servomechanism of injection molding machines. Based on MBS, virtual design model has been developed for a direct forcing clamping mechanism. A synchronizing controller is designed and combined with adaptive feedforward control to accommodate mismatches between the real plant and the linear plant model used. From tracking control simulations, it is shown that significant reduction in position tracking error is achieved through the use of proposed control scheme.

In this paper, the field vibration measurement tests have been conducted for investigating the exact causes of the abnormal vibration accident which occurred on last July 5, 2011 in TechnoMart, a 39 story steel building structure. The vertical accelerations of the building floors were measured under the 4D movie-theater operation and human rhythmic movements in a fitness center which were estimated as ones of the vibration sources. From field tests, it could be identified that the building has global vertical vibration mode of 2.7 Hz natural frequency and human group rhythmic movements having frequency component mainly close to 2.7 Hz in a fitness center caused the resonance of the vertical mode. Especially, the fact that the identified damping ratio of the vertical mode by observing the free vibration response after the human group excitation was just 0.3%, implies that response amplification could be so significant that only 23 people could excite the 39 story building having the total mass of 30 thousands of metric ton move globally up and down. Tuned mass damper (TMD) is being considered as a measure for keep this resonance by adding damping to the building. The TMD design results shows that the acceleration level resulting from the same human excitation can be reduced to one fourth of that of the building without TMD.

This paper presents a robust motion tracking control of a cylinder-toggle servomechanism for injection molding machines. Virtual design model has been developed for a five-point type toggle mechanism. A sliding function is defined and combined with PID control to accommodate mismatches between the real plant and the linear model used. From tracking control simulations, it is shown that significant reduction in position tracking error is achieved with clamping force build-up through the use of proposed control scheme.

The study investigated USFK’s crisis communication responding to the case of two Koran girls’ death. The two girls were hit by an American tank accidently. The accident has resulted in anti-American demonstrations by a large number of South Korean. The current research attempted to see what problems USFK’s crisis communication with Korean publics. Through analyzing USFK news release in Korea and Army News (ARNEWS) in America regarding the case, the study answered what crisis communication strategies USFK used and How the USFK responded to the crisis. The results showed that USFK used full apology strategy and its crisis response was immediate, but prior reputation of USFK seemed making USFK’s effort fruitless.

This study investigates the effect of corporate social responsibility (CSR) and corporate nationality on public reactions to negative news about corporations. To explain how CSR activity works as a buffer for a negative issue of an organization, we propose a halo effect theory. This study conducted an experiment using a 2 (CSR activity vs. no CSR activity) x 2 (domestic company vs. foreign company) between-subject design. For this experiment, we developed a negative news story about a fictitious Asian local company. The dependent variable was whether individuals showed willingness to take actions against this company. We found that both CRS activities and corporation nationality have the main effects on individuals' willingness to take an action against the local company. CSR activities and the company's national identity (being domestic) were significant positive factors in attenuating participants' intention to take action against the local company. Further, there was a significant interaction effect of...

This paper deals with the issue of position tracking control with load-sensing for a valve-controlled cylinder system using speed-controlled fixed displacement pump. This is achieved by incorporating a sliding-function based feedforward controller with a feedback control system. The whole feedback control system is composed of a pair of interconnected subsystems, that is, a valve-controlled cylinder system and a load-sensing control system. Experiments show that sliding-mode-based position tracking control in the load sensing control system can accomplish significant reduction in the input energy to a pump compared to a conventional valve-controlled cylinder system, while exhibiting the same position tracking control accuracy.

A waffle-shaped precast concrete panel named WAS has been newly developed as a floor system. Compared to the conventional double tee (DT), the WAS has a more spacious connection area between the panels while having a shallower depth, which possibly results in an enhanced performance of the connection. Experimental studies were performed to examine the flexural behavior of the WAS according to several primary parameters: the panel types, prestress levels applied to the panels, panel sizes, and the existence of steel ties. Connection tests were also performed on the short and long edges of each panel against out-of-plane shear. The test results showed that the WAS panels yields satisfactory flexural capacity similar to the DT up to ultimate state, and they satisfy the deflection limit for serviceability while their stiffnesses were less than those of DT panels. It was also found that the ultimate flexural strength of the WAS panel increases as the applied prestress increases, and that the connections can undertake the applied bending moment and properly transfer the developed shear force between WAS panels. The enhanced performance of the WAS connection makes it possible to efficiently design the panels addressing the moment distribution, and to enhance the serviceability (less deflection and cracking) and structural continuity/integrity of the WAS system while still being able to reduce its depth.

The present research integrates the core aspects of anger with the theory of planned behavior to investigate factors influencing online activism in a Web site. This study conducted online survey, and the sample was members who joined the V4400 Sobi-ja-heem Web site. The Web site Sobi-ja-heem was initiated by a consumer who was irritated at the cell phone manufacturer Samsung Inc. because its model, "Anycall" had major product defects such as the malfunction of the camcorder, poor tone quality, fuzziness of the screen, and broken text messages. The findings suggests that adding anger in Theory of Planned Behavior (TPB) enhances the explanatory power of the theory in predicting an intention to participate in activities to correct the issue, which indicates the possibility of combining emotion and the TPB in the prediction of online activism.

PurposeThis paper aims to identify how the news media cover organizational crisis responsibility and crisis response strategies and, if at all, how they differ by crisis types.Design/methodology/approachThe approach takes the form of a content analysis of level of responsibility (individual versus organizational level) and organizational response strategies in news coverage of major crisis events during 2006 in three newspapers.FindingsSignificant differences were found between preventable crises and accidental crises: most preventable crises news coverage focused more on the individual level of responsibility, while accidental crises news used the organizational level of responsibility. The significant differences of organizational response strategies indicated that preventable crises news coverage frequently reported denial strategies, while accidental crisis news covered deal with strategies more.Research limitations/implicationsThe study is limited to the samples of the three newspapers and the period 2006.Practical implicationsThis study suggests that crisis managers should always check the crisis news coverage, and media bias and orientation, and try to have good relations with the media to deliver the right message to the public during a crisis.Originality/valueDespite the importance of the media's role in the public's perception of crisis responsibility, there is a lack of systematic analysis of level of crisis responsibility.

This study investigated the public's perception toward organizational crisis response strategies by using a 2 × 2 × 2 between-subject factorial design with level of responsibility (individual vs. organizational level), organizational response (causal and treatment responsibility), and two countries (the United States vs. South Korea). Students responded to hypothetical news stories. The results showed that students in a highly collectivistic culture had more anger, negative attitudes, and impressions toward the organization than students in a highly individualistic culture, when the organization used the individualistic-level strategy. The results suggest organizations may benefit by using a strategy in which they accept responsibilities for crises.

This paper deals with the use of Neural Network based PID control scheme in order to assure good tracking performance of a pneumatic X-Y table. Pneumatic servo systems have inherent nonlinearities such as compressibility of air and nonlinear frictions present in cylinder. The conventional PID controller is limited in some applications where the affection of nonlinear factor is dominant. In order to track the reference model output, the primary control function is provided by the PID control and then the auxiliary control function is given by neural network for learning and compensating the inherent nonlinearities, A self-excited oscillation method is applied to derive the dynamic design parameters of a linear model. The experiment using the proposed control scheme has been performed and a significant reduction in tracking error is achieved.

This study examines Viacom's MTV localisation strategy in East Asia – specifically South Korea, China and Japan, which should be interpreted not in the context of globalisation but of glocalisation, because the strategy for entry into foreign markets means that localised programming and business modes are more successful than other strategies (e.g. standardisation or unification). The results of this study show that Viacom's MTV used joint ventures as its primary localised business mode in East Asia. This particular mode is more efficient and beneficial to an international company like Viacom in countries that are not only distant, but also culturally, politically, financially and economically challenging to them. In terms of localised programming, MTV Korea, MTV China and MTV Japan all used local staff and local languages, and all three channels showed different trends in the types of programmes they broadcast: MTV Korea aired more local programmes, MTV Japan aired more Western music and MTV Chi...

This paper deals with the issue of robust motion control of a clamp-cylinder for injection moulding machines driven by a pair of speed-controlled fixed displacement pumps. As a fundamental step prior to tracking controller design, a feedback control system is suggested by implementing a position control loop in parallel with a system pressure control loop. A discrete-time sliding mode control scheme is developed for enhancing the tracking performance under inherent nonlinearities. Consequently, a significant reduction in tracking error is achieved for both position and pressure control applications.

Existing aeroelastic analyses for finite wings have been mostly limited to cases with a steady freestream. In reality, however, the inflowing freestream can often be unsteady and pulsating. Therefore, this paper presents unsteady aerodynamic and aeroelastic analyses for a finite wing under a pulsating freestream. A new three-dimensional unsteady vortex lattice model under a pulsating freestream has been developed in discrete-time domain to examine unsteady aerodynamic forces acting on a vibrating wing. The structural behavior of the wing has been analyzed using a three-dimensional plate model. An aeroelastic model is then constructed by coupling the unsteady aerodynamic model with the structural model. Since the freestream velocity is assumed to be time-varying, the flutter onset of a wing under pulsating freestream is predicted by Floquet analysis. Numerical results of an untwisted and untapered wing show that the new time domain method can predict the aeroelastic stability as well as time history of the isolated wing under a pulsating freestream.

This paper focused on the application of finite element model updating technique to evaluate the structural properties of the reinforced concrete specimen using the data collected from shaking table tests. The specimen was subjected to six El Centre (NS, 1942) ground motion histories with different peak ground acceleration (PGA) ranging from 0.06 g to 0.50 g. For model updating, flexural stiffness values of structural members (walls and slabs) were chosen as the updating parameters so that the converged results have direct physical interpretations. Initial values for finite element model were determined from the member dimensions and material properties. Frequency response functions (i.e. transfer functions), natural frequencies and mode shapes were obtained using the acceleration measurement at each floor and given ground acceleration history. The weighting factors were used to account for the relative confidence in different types of Inputs for updating (j.e. transfer function and natural frequencies) The constraints based on upper/lower bound of parameters and sensitivity-based constraints were implemented to the updating procedure in this study using standard bounded variable least-squares(BVLS) method. The veracity of the updated finite element model was investigated by comparing the predicted and measured responses. The results indicated that the updated model replicates the dynamic behavior of the specimens reasonably well. At each stage of shaking, severity of damage that results from cracking of the reinforced concrete member was quantified from the updated parameters (i.e. flexural stiffness values).

Message boards are possible places for sports fans to actively express and exchange their opinions. The purpose of this study is to explore the typology of message board uses on sports websites. The analysis of 1350 topics on eight Major League Baseball teams’ websites for 10 days revealed that: (1) the cognitive need of using message boards in a sports organization's website was an outstanding motivation; (2) sharing opinions was a new motivation category (compared to traditional uses and gratifications) that was found to be dominant; and (3) winning teams and losing teams’ message boards were significantly different in terms of number of topics, number of users, and optimism score; however, messages seemed to be optimistic. Implications for public relations practitioners suggest that the message board is an excellent monitoring tool for them as well as a fine communication tool between sports organizations and fans.

In this study, based on the results from the sinusoidal base excitation analyses of a single degree of freedom system with a tuned mass damper (TMD), it is verified that optimal friction force can improve the performance of a TMD like a linear viscous damper which has been usually used in general TMD. The magnitude of the optimal friction increases with increasing mass ratio of the TMD and decreases with increasing structural damping. Particularly, it is observed that the optimized friction force gives better control performance than the optimized viscous damping of the TMD. However, because the performance of the TMD considerably deteriorates when the friction force increases over the optimal value, it is required to keep the friction force from exceeding the optimal value.

This study investigated the effect of motivations for online chatting and gender factors in self-disclosure in adolescents' online chatting. Participants were 260 high school students (128 female, 132 male) who participated in online chatting. The results revealed that self-disclosure in online chatting differed by motivation, but gender was not a significant variable for explaining self-disclosure.

In this study, tile performance of a passive tuned mass damper (TMD) and a semi-active tuned mass damper (STMD) was evaluated in terms of seismic response control of elastic and inelastic structures under seismic loads. First, elastic displacement spectra were obtained for the damped structures with a passive TMD, which was optimally designed using the frequency and damping ratio presented by previous study, and with a STMD proposed in this study. The displacement spectra confirm that STMD provides much better control performance than passive md with less stroke. Also, the robustness or the TMD was evaluated by off-tuning the frequency of the TMD to that of the structure. Finally, numerical analyses were conducted for an inelastic structure of which hysteresis was described by Bouc-Wen model and the results indicated that the performance of the passive TMD of which design parameters were optimized for a elastic structure considerably deteriorated when the hysteretic portion or the structural responses increased, while the STMD showed about 15-40% more response reduction than the TMD.

In this paper, we propose a noninvasive sensor system for discriminating mobility pattern of a resident on the bed without inconvenience. The proposed system consists of a thin and wide film style of piezoelectric force senor, a signal processing board, and data collecting program. There are four different types of motion that were simulated by non-patient volunteers. About 10,000 experimental motions of subjects were performed. Sensor data by human motions were collected and preprocessed by a moving average filter, transformed by FFT, and classified by the k-NN algorithm with k = 1. The experiment yielded the overall discrimination rate of 89.4 %. The proposed system will contribute to differentiating mobility pattern on a bed and distinguishing the physical characteristics of a person.

The corrosion reinforcing steel in concrete structures is detrimental to its service life. In order to increase lifespan and maintain serviceability, a qualitative measurement technique that can measure the extent of corrosion of reinforcing steel needs to be developed. While considerable researches have been carried out focusing only on detecting corrosion and restraining the progress of corrosion, a qualitative measurement technique that can measure the amount of corrosion in rebar need to be developed. The purpose of this research is to develop a new technique to measure the corrosion level of rebar using accumulated thermal data. Accumulated thermal data were gathered using infrared camera and digitized to distinguish the difference between various corrosion levels of rebar. The test results showed that the higher level of corrosion displays the higher level of temperature. Temperature of reinforcing steel is not severely affected by ambient temperature, however, concrete surface temperature increased as ambient temperature increased.

This paper describes a Neural Network based PID control scheme for pneumatic NC axes. Pneumatic systems have inherent nonlinearities such as compressibility of air and nonlinear frictions present in cylinder. The conventional PID controller is limited in some applications where the affection of nonlinear factor is dominant. A self-excited oscillation method is applied to derive the dynamic design parameters of linear model. The gains of PID controller are determined using a self tuning scheme. The experiments of a trajectory tracking control using the proposed control scheme are performed and a significant reduction in tracking error is achieved by comparing with those of a PID control.

Functional 3D laryngeal CT (F3DLxCT) is an informative tool for visualizing the active changes in length, tension and mass of the vocal folds for pitch control. Furthermore, volume defects and level differences of paralyzed vocal folds are easily detectable with this new technique.To evaluate the clinical feasibility of F3DLxCT images, which can provide clear coronal images of the vocal fold in each anteroposterior direction during phonation and in the resting state.FLxCT images were reconstructed to three dimensions to visualize laryngeal motion. FLxCT was performed in four normal controls and in four patients with unilateral vocal fold paralysis in the resting state and during phonation with three vowel sounds of different pitch. 3D images were reconstructed with segmentation and a surface-rendering algorithm on a PC, using the DICOM file of axial images.The dynamic vocal fold 3D image during phonation could visualize that the thickness and volume were decreased in relatively to the pitch increase. Typical subglottic shoulder-like image formation and ventricular widening were noted with the high-pitch tone.

In this paper, a neural network controller that can be implemented in parallel with a PD controller is suggested for motion control of a hydraulic servo cylinder. By applying a self-excited oscillation method, the system design parameters of open loop transfer function of servo cylinder system are identified. Based on system design parameters, the PD gains are determined for the desired closed loop characteristics. The Neural Network is incorporated with PD control in order to compensate the inherent nonlinearities of hydraulic servo system. As an application example, a motion control using PD-NN has been performed and proved its superior performance by comparing with that of a PD control.

Reinforcement corrosion is a major influencing factor in deterioration of reinforced- and prestressed-concrete structures. Concrete structures exposed to chlorides from seawater, deicing chemicals, salt, salt water, brackish water, or spray from these sources are more vulnerable to corrosion. The corrosion characteristics of corroded reinforcing bars are a very important topic in the durability and strength of concrete structures. Both experimental and analytical studies on this topic, however, are scarce to the point of nonexistence. In order to qualitatively and quantitatively understand the effect of corrosion level on the bond strength and development length in RC slab members, a series of tests are carried out. The reinforcing bar of the specimen is corroded after concrete casting. One type of reinforcing bar HD10 is corroded to 1%, 2%, 3%, 5%, 7%, 10%, and 15% of its original cross-sectional area of the reinforcement using current-induced accelerated corrosion technique. After the effective corrosion is applied, flexural tests are performed. The analysis results show that the effect of corrosion level on bond strength and development length was apparent. In addition, after 2% corrosion level, the current design code for development length should be reviewed and more studies are needed in the future for verification.

This paper deals with the issue of Neural Network-based control for a rodless pneumatic cylinder system which is utilized for a pneumatic XY-plotter. In order to identify the system design parameters, the open loop response of a pneumatic rodless cylinder controlled by a pneumatic servovalve is investigated by applying a self-excited oscillation method. Based on the system design parameters, the PD feedback compensator is designed and then Neural Network is incorporated with it. The experiment of a trajectory tracking control using a PD-NN has been performed and proved its excellent performance by comparing with that of a PD feedback compensator.

Because a quantity wireless internet contents is much less than wired internet contents, it exist high necessities that wired internet contents should be converted into wireless internet contents. The conversion server implemented in this paper, automatically recognizes the type of user agents when they request, retrieves source documents on the web site specified by an URL, generates metaXML documents as an intermediate form, and converts them wireless markup documents appropriate for user agents. The conversion server interoperates with the image converter for image conversion and the clipper which is an authoring tool for clipping existing wired internet documents. We performed experiments about capability of the conversion server transcoding static/dynamic web pages specified by an URL. According to performance results on dynamic web pages, the conversion server showed better throughput when a thread pool in the terror maintains 5 threads compared with 1 and 10 threads.

This paper examines an application of Neural Network for identification and control of a servovalve controlled hydraulic cylinder system. The linearized transfer function of a nonlinear plant is determined by applying a selfexcited oscillation. Neural Network is utilized on-line in mapping the inherent nonlinearities as well as in adaptive identification of system parameters. Neural Network controllers having variable proportional gain together with velocity feedback gain characteristics have been employed. The effectiveness of the Neural Network is confirmed through computer simulations and experiments.