• Journal of IKEEE
• /
• v.22 no.4
• /
• pp.1195-1201
• /
• 2018

This paper interprets the relationship between the physical activity of the human and the signal of the brain to show the meaningful results in the process of sending and receiving information to the connected muscles. When a person works or thinks, a specific brain signal is generated from the brain and being trasmmited to the connected part. The EMG signal, which has muscle activity information, outputs the result of the muscle activation as an electrical signal, which outputs muscle activity information usually due to muscle contraction and relaxation. The purpose of this study is to analyze the relationship between the two signals, which are difficult to identify easily by visual data extraction and data acquisition by extracting such EMG and EMG in real time.

• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.6
• /
• pp.74-82
• /
• 1997

We provide a set of information on technologies to draw meaningful action plans for the internationalization on National R&D activities. In this study, we employed a modiffed Delphi method to evaluate levels of our technological capabilities and developed countries as well. We investigated technology acquis- tion methodologies, technology characteristics and various aspects of international cooperation in terms of technology. Then, we analyzed final responses of participants (i.e., the third round results of Delphe method) to see the correlation among various factors in developing technologies through international R&D cooperation. The technology classification used in this research was developed by STEPI (Science and Technology Policy Institute). In conclusion, levels of our technologies were investigated to be between the stage of imi- tating/absorbing advanced thechnologies and the stage of digesting acquired technologies. Especially, com- paring with other technologies, mechanical engineering was evaluated to be almost near the stage of digesting acquired technology(the middle level stage of technology). Our overal technological capabilities were evaluated to be 40 .approx. 60% of top level countries.

• Asia Marketing Journal
• /
• v.5 no.2
• /
• pp.49-70
• /
• 2003

현재 우리 나라 약업계에서는 의약분업, 일부 의약품의 슈퍼마켓에서의 판매 등의 급격한 환경변화로 약국경영형태의 혁신적인 변화가 진행되고 있다. 본 논문에서는 현재 약업계에서는 급속히 발전되고 있으나 학문적으로는 연구된 적이 거의 없는 볼런터리 체인형태의 협업체 약국에 초점을 맞추어 가맹약국과 체인본부와의 거래관계의 질과 체인약국 시스템의 효율적인 운영 및 관리방안을 알아보았다. 본 논문에서는 연구목적들을 달성하기 위하여 특정 협업체 약국체인에 참여하고 있는 168개의 가맹약국을 대상으로 자료를 전국적으로 수집하였으며, 구조방정식 모형을 사용하여 연구가설을 검정한 분석결과는 다음과 같다. 첫째, 약국체인시스템에 투자한 가맹약국의 거래특유자산과 기업가정신은 관계규범에 유의한 영향을 주었으나, 환경의 불확실성은 정보교환, 결속력, 운영유연성 등의 관계규범에 유의적인 작용을 하지 못하였다. 둘째, 거래특유자산과 동기적 투자는 체인구성원들간의 상호의존성을 유의하게 높였으나, 대체안의 획득가능성과 관계규범은 상호의존성에 중요한 영향을 미치지 못하였다. 마지막으로, 체인구성원간의 관계규범과 상호의존성이 관계의 질 즉 가맹약국들이 거래에서 느끼는 만족, 체인본부에 대한 신뢰, 약국체인에 지속적으로 참여하려는 몰입에 주는 영향을 분석하였다. 상호의존성은 관계규범과 신뢰에 영향을 주고, 관계규범은 만족을 통하여 신뢰에 유의한 영향을 주었으며, 그리고 신뢰는 몰입에 유의적인 영향을 주었다.

• Radiation Oncology Journal
• /
• v.20 no.1
• /
• pp.41-52
• /
• 2002

Purpose : 3D conformal radiotherapy, the optimum dose delivered to the tumor and provided the risk of normal tissue unless marginal miss, was restricted by organ motion. For tumors in the thorax and abdomen, the planning target volume (PTV) is decided including the margin for movement of tumor volumes during treatment due to patients breathing. We designed the respiratory gating radiotherapy device (RGRD) for using during CT simulation, dose planning and beam delivery at identical breathing period conditions. Using RGRD, reducing the treatment margin for organ (thorax or abdomen) motion due to breathing and improve dose distribution for 3D conformal radiotherapy. Materials and Methods : The internal organ motion data for lung cancer patients were obtained by examining the diaphragm in the supine position to find the position dependency. We made a respiratory gating radiotherapy device (RGRD) that is composed of a strip band, drug sensor, micro switch, and a connected on-off switch in a LINAC control box. During same breathing period by RGRD, spiral CT scan, virtual simulation, and 3D dose planing for lung cancer patients were peformed, without an extended PTV margin for free breathing, and then the dose was delivered at the same positions. We calculated effective volumes and normal tissue complication probabilities (NTCP) using dose volume histograms for normal lung, and analyzed changes in doses associated with selected NTCP levels and tumor control probabilities (TCP) at these new dose levels. The effects of 3D conformal radiotherapy by RGRD were evaluated with DVH (Dose Volume Histogram), TCP, NTCP and dose statistics. Results : The average movement of a diaphragm was 1.5 cm in the supine position when patients breathed freely. Depending on the location of the tumor, the magnitude of the PTV margin needs to be extended from 1 cm to 3 cm, which can greatly increase normal tissue irradiation, and hence, results in increase of the normal tissue complications probabiliy. Simple and precise RGRD is very easy to setup on patients and is sensitive to length variation (+2 mm), it also delivers on-off information to patients and the LINAC machine. We evaluated the treatment plans of patients who had received conformal partial organ lung irradiation for the treatment of thorax malignancies. Using RGRD, the PTV margin by free breathing can be reduced about 2 cm for moving organs by breathing. TCP values are almost the same values $(4\~5\%\;increased)$ for lung cancer regardless of increasing the PTV margin to 2.0 cm but NTCP values are rapidly increased $(50\~70\%\;increased)$ for upon extending PTV margins by 2.0 cm. Conclusion : Internal organ motion due to breathing can be reduced effectively using our simple RGRD. This method can be used in clinical treatments to reduce organ motion induced margin, thereby reducing normal tissue irradiation. Using treatment planning software, the dose to normal tissues was analyzed by comparing dose statistics with and without RGRD. Potential benefits of radiotherapy derived from reduction or elimination of planning target volume (PTV) margins associated with patient breathing through the evaluation of the lung cancer patients treated with 3D conformal radiotherapy.

• Korean Business Review
• /
• v.12
• /
• pp.209-237
• /
• 1999

With the increasing speed of internationalization of corporations under WTO system foreign direct investment is considered as the important means of international cooperation as well as avoiding trade barrier. From this point of view the study on foreign direct investment of Korean corporations is of great importance. Many studies till now, however, are concerned with the macroscopic analysis of foreign direct investment of Korean corporations, not with the establishment of strategy appropriate to the environment of host country and the investment performance. In order to meet the problems mentioned above this thesis aims at accomplishing the following three tasks. (1) synthetic assessment of existing theories of foreign direct investment. (2) systematic adjustment of factors of environment in the foreign direct investment activities. (3) analysis of above factors in the foreign direct investment of Korean textile industry and proper proposal of strategic model for the individual corporation. The results of analysis according to the aim of the study are as follows: (1) To lead foreign direct investment successfully, variable and effective information-presentation should be offered with priority. (2) The investment strategy through regional diversification is required. (3) The localization of decision making has to be attempted assertively. (4) The global network system is needed for more recommendable foreign direct investment. (5) More aggressive and outgoing attitude like developing into the local market and obtaining the high-technology is desperately needed.

• Journal of Global Scholars of Marketing Science
• /
• v.10
• /
• pp.1-26
• /
• 2002

The present study examines the role of subjectively perceived factors of the attitude toward web shopping in forming an intention to use a web shopping intention. An integrative research model is presented and tested empirically. It includes the following three aspects of belief in Davis' TAM: perceived usefulness, perceived ease of use, perceived enjoyment. Specially, internet self-efficacy, or the belief in one's capabilities to organize and execute courses of Internet actions required to produce given attainments, is a potentially important factor in efforts to gain more favorable attitude toward web shopping close the digital divide that separates experienced Internet users from novices. Prior research on Internet self-efficacy has been limited to examining specific task performance and narrow behavioral domains rather than overall attainments in relation to general Internet use, and has not yielded evidence of reliability and construct validity. Survey data were collected to develop a reliable operational measure of Internet self-efficacy and to examine its construct validity. Also, much previous research has established that perceived ease of use is an important factor influencing user acceptance and usage behavior of information technologies. However, very little research has been conducted to understand how that perception forms and changes over time. The present study examines that higher internet self-efficacy is more getting favorable web shopping attitude, and web shopping intention as more as usefulness, enjoyment through the internet.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.41 no.4
• /
• pp.395-403
• /
• 2016

This paper introduces a multi-cell search method for heterogeneous networks (HetNet), in which user equipments need to search multiple cells in its vicinity simultaneously. Due to the difficulty of acquiring channel informations for multiple cells, a non-coherent approach is preferred. In this paper, a non-coherent single-cell search scheme using a weighted vector is proposed, and the successive interference cancellation based multi-cell search algorithm is devised. In order to improve cell search performance, the weighted vector is designed in a way to exploit the general characteristic of wireless channel. Based on the fact that the performance of the proposed single-cell search scheme deviates slowly from the one using the optimal weighted vector, a universal weighted vector is also proposed, which shows the performance close to the optimal ones for various channel environments and signal-to-noise ratio regimes. Simulation results confirm that the proposed multi-cell search algorithm is capable of identifying cells more accurately with the help of the proposed single-cell search scheme, and can detect the remaining cells more effectively by removing the signals of the identified cells from the received signal.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.48 no.3
• /
• pp.125-131
• /
• 2011

Water leak detection system is a system based on wireless sensor networks(WSNs) which detect a leak on water supply, localize the leak position and finally inform a water management center. A traditional leak detection method is to use experienced personnel who walk along a pipeline listening to the sound that is generated by the leaks and their effectiveness depend on the experience of the user. Also making more successful detection, it should be processed at middle of the night when people do not use water, as the result users have to operate the leak detection system at midnight. In this paper, we propose a new method for the water leak detection system based on the WSNs and describe it in detail. Leak detection devices which detect a leakage of water transmit and receive the result of water leak detection with each other by configuring WSNs to improve reliability of the detection result. Also, we analyzed the sound from water flowed in pipeline, proposed the pre-signal processing to separate a leakage sound from noisy sound. And lastly, It is especially important to make a time synchronization with water leak detection devices that are installed on the pipeline, we used 1PPS(1 Pulse Per Second) signal generated by GPS, therefore we could get a precise time synchronization. The proposed system set up in Namyangju and performances were evaluated.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.20 no.1
• /
• pp.20-23
• /
• 2016

Purpose Because of heart movement, PET image of heart is very blur. So, PET scan gated with ECG is necessary to improve a spatial resolution of heart PET image. In this study, we will evaluate a image quality of both gated $^{13}N-ammonia$ PET scan and non-gated one. Materials and Methods Before start a heart PET, we attached a ECG electrode on patients (n = 5, $aged=54{\pm}17$). And we started a list mode PET scan that used by a mCT40 PET/CT (siemens, germany) during 10 minute, injected $^{13}N-ammonia$ ($378{\pm}50MBq$) to a patients at same time. By using this list mode data, we reconstructed both gated PET image and non-gated PET image. Then we analysed a profiles of those images, performed a blind test, and subtracted a gated image on non-gated image. Results FWHM of a gated image is improved about 23% and there is a differency count distribution at a subtracted image from non-gated image to a gated image. But in case of blind test, everybody select the gated image as a better quality among each images. Conclusion As a result, we can find that image quality will improve by using gated PET scan. In additional, we can calculate a EF valve, apply QGS, QPS of PET. Therefore, the gated PET scan help improving an accuracy, applying a more information for a diagnosis.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.4C
• /
• pp.341-348
• /
• 2009

In this paper, we propose a grouping technique for the SDD(Synchronous Digital Duplexing) based on OFDMA(Orthogonal Frequency Division Multiple Access). The SDD has advantages of increasing data efficiency and flexibility of resource since SDD can transmit uplink signals and downlink signals simultaneously by using mutual time information and mutual channel information, obtained during mutual ranging process. However, the SDD has a disadvantage of requiring additional CS to maintain orthogonality of OFDMA symbols when the sum of mutual time difference and mutual channel length between AP(access point) and SS(subscriber station) or among SSs are larger than CP length. In order to minimize the length of CS for the case of requiring additional CS in SDD, we proposes a grouping technique which controls transmit timing and receive timing of AP and SS in a cell by classifying them into groups. Performances of the proposed grouping technique are evaluated by computer simulation.