• Title/Summary/Keyword: 역방향

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Capacity Variation of a Microcell due to Power Control Error in and Overlaid Macrocell/Microcell CDMA System (매크로셀내에 마이크로셀이 중첩된 CDMA 시스템에서 전력제어오차로 의한 마이크로셀의 용량 변화)

  • 강희곡;김영철;노재성;조성준
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.1
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    • pp.8-17
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    • 2000
  • The BER performance and the capacity variation of a microcell due to power control error(PCE) is analyzed on service types(data and voice, respectively) for the reverse link of an overlaid cell CDMA system. The procedure of analysis is followed as: First, we calculate BER performance according to PCE. Next, we find the minimum SNR for voice service, BER=TEX>$10^{-3}$, and data service, BER=TEX>$10^{-5}$. Then, according to the calculated SNR, we find the maximum capacity of a microcell and macrocell and the capacity of a microcell where interference is considered is found and analyzed with that in perfect power control. We get to the results as follows. The BER performance in 1 dB PCE is similar to that in perfect power control, however, with a increase in PCE, the BER performance is largely degraded. In terms of capacity, it is shown that if the PCE is equal or less than 2 dB, the effect of the PCE on voice service is more than that on data service, but if the PCE is equal or more than 3 dB, effect of the PCE on data service is more than that on voice. Besides, if the PCE is equal or less than 2 dB, both PCE and interference should be considered to calculate the capacity of a microcell, but if the PCE is equal or more than 3 dB, interference can be negligible since the effect of PCE is much stronger than that of interference. Therefore, the microcell should be located where $R_d$, the ratio of a microcell to a macrocell radius, is equal to 0.1, and d, the ratio of the distance between a microcell and a macrocell to the macrocell radius, is equal or more than 0.5, in order to obtain a appropriate microcell capacity against interference. If $\sigma$ is adjusted to less than 2 dB, we may get equal or more than 70% of the maximum microcell capacity.

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The Effect of Internalized Shame and Self-Control on Interpersonal Relationships in Stroke Patients (내면화된 수치심과 자기통제력이 뇌졸중 환자의 대인관계에 미치는 영향)

  • Hwang, Jung-Ha;Lim, Jae-Ho
    • The Journal of Korean society of community based occupational therapy
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    • v.10 no.3
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    • pp.63-74
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    • 2020
  • Objective : The purpose of this study is to investigate the influence of internal shame and self-control on interpersonal relationships in stroke patients, and to provide evidence and information necessary for clinical trials by analyzing the relationship. Methods : For this study, 150 stroke patients receiving occupational therapy services at institutions where occupational therapists work in Jeollanam-do and Chungnam regions were targeted through email and mail from March 1, 2019 to April 30, 2019. The questionnaire was conducted using general characteristics, Relationship Change Scales(RCS), Self-Control Scales(SCS), and Internalized Shame Scale(ISS) questionnaire. Descriptive statistical analysis was performed for the general characteristics of the study subjects, and t-test and one-way batch variance analysis (ANOVA) were used to compare interpersonal relationships according to general characteristics. The relationship between internalized shame, self-control, and interpersonal competence was analyzed by Pearson's correlation coefficient, and multiple regression analysis was performed to determine the factors affecting interpersonal relationships of stroke patients. Results : As a result of comparing interpersonal competence according to general characteristics, significant differences were found in terms of age and education level. Interpersonal relationships and internalized shame, internalized shame and self-control showed a negative correlation, and self-control and interpersonal relationships had a positive correlation, but self-control was the sub-factors of interpersonal relationships such as openness, sensitivity, intimacy, It was not statistically significant with the communication item. In addition, the items of inadequacy (β =-0.32) and adventure seeking (β =-0.23), which are sub-areas of internalized shame, affect the negative direction, and physical activity (β =0.22), which is the sub-area of self-control and the self-centered (β =0.24) item was found to have an effect on the positive direction. Conclusion : Therefore, additional research is needed that can operate a rehabilitation treatment program that applies various psychological factors for the formation of interpersonal relationships among stroke patients.

Quality Assurance for Intensity Modulated Radiation Therapy (세기조절방사선치료(Intensity Modulated Radiation Therapy; IMRT)의 정도보증(Quality Assurance))

  • Cho Byung Chul;Park Suk Won;Oh Do Hoon;Bae Hoonsik
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.275-286
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    • 2001
  • Purpose : To setup procedures of quality assurance (OA) for implementing intensity modulated radiation therapy (IMRT) clinically, report OA procedures peformed for one patient with prostate cancer. Materials and methods : $P^3IMRT$ (ADAC) and linear accelerator (Siemens) with multileaf collimator are used to implement IMRT. At first, the positional accuracy, reproducibility of MLC, and leaf transmission factor were evaluated. RTP commissioning was peformed again to consider small field effect. After RTP recommissioning, a test plan of a C-shaped PTV was made using 9 intensity modulated beams, and the calculated isocenter dose was compared with the measured one in solid water phantom. As a patient-specific IMRT QA, one patient with prostate cancer was planned using 6 beams of total 74 segmented fields. The same beams were used to recalculate dose in a solid water phantom. Dose of these beams were measured with a 0.015 cc micro-ionization chamber, a diode detector, films, and an array detector and compared with calculated one. Results : The positioning accuracy of MLC was about 1 mm, and the reproducibility was around 0.5 mm. For leaf transmission factor for 10 MV photon beams, interleaf leakage was measured $1.9\%$ and midleaf leakage $0.9\%$ relative to $10\times\;cm^2$ open filed. Penumbra measured with film, diode detector, microionization chamber, and conventional 0.125 cc chamber showed that $80\~20\%$ penumbra width measured with a 0.125 cc chamber was 2 mm larger than that of film, which means a 0.125 cc ionization chamber was unacceptable for measuring small field such like 0.5 cm beamlet. After RTP recommissioning, the discrepancy between the measured and calculated dose profile for a small field of $1\times1\;cm^2$ size was less than $2\%$. The isocenter dose of the test plan of C-shaped PTV was measured two times with micro-ionization chamber in solid phantom showed that the errors upto $12\%$ for individual beam, but total dose delivered were agreed with the calculated within $2\%$. The transverse dose distribution measured with EC-L film was agreed with the calculated one in general. The isocenter dose for the patient measured in solid phantom was agreed within $1.5\%$. On-axis dose profiles of each individual beam at the position of the central leaf measured with film and array detector were found that at out-of-the-field region, the calculated dose underestimates about $2\%$, at inside-the-field the measured one was agreed within $3\%$, except some position. Conclusion : It is necessary more tight quality control of MLC for IMRT relative to conventional large field treatment and to develop QA procedures to check intensity pattern more efficiently. At the conclusion, we did setup an appropriate QA procedures for IMRT by a series of verifications including the measurement of absolute dose at the isocenter with a micro-ionization chamber, film dosimetry for verifying intensity pattern, and another measurement with an array detector for comparing off-axis dose profile.

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The Effects of Consumer Value Cognition on Benefits and Attributes of Culture-Art Products (문화예술상품 소비자의 가치인식이 추구혜택과 상품속성에 미치는 영향)

  • Shin, Eun Joo;Rhee, Young Sun
    • Asia Marketing Journal
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    • v.14 no.2
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    • pp.177-207
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    • 2012
  • Today's consumers perceive consumption as a representation of themselves. It is not simply an act that fulfills a consumer's physical and practical needs. Even in terms of life quality, consumers increasingly want to achieve an emotional and sensible experience through consumption. Consumers now make decisions based on their need to express their position in relation to other people, pursue emotional satisfaction, and try to improve the quality of life. Culture-art products that meet such internal and external demands of consumers have made significant improvements in both quantity and quality, because of the social interest and policy support. The recognition of personal and social values of culture and arts has brought about interest in and need for culture-art products. Businesses have agilely embraced such change and actively implemented various marketing strategies utilizing culture and arts. For example, businesses began to sponsor artists who produce culture-art products while building facilities for cultural and art performances or exhibitions. Businesses have also provided performances and exhibitions free-of-charge or at affordable prices. As a result, the supply in the market has started to exceed its demand as is often the case in many of other markets. However, such imbalance has occurred not because of over-supply but because of a lack of demand. Given these circumstances, the government and culture and art related organizations, which had mainly concentrated on the supply side, started to recognize the importance of creating personal and social values in culture and arts. As a result, the government and various organizations are now creating various strategies that include policy measures to achieve their new found goal. Unfortunately however, such efforts are not meeting the expectations. Focusing on above-mentioned circumstances and problems, this study aims to find measures to create demand for culture-art products in the internal conditions of those who consume culture-art products. In other words, given that the demand for culture-art products has not increased despite all external conditions to encourage consumption, this study aims to find the reasons in consumers' value judgment on culture-art products. Though there were recent studies on culture-art products that applied consumer behavior on marketing theories, most of them focused on peripheral aspects such as people's motivation for or satisfaction from watching culture-art events. Hence, there is a need to understand what kind of value consumers perceive from culture-art products and how such value cognition leads to consumption in a comprehensive manner. This study acts as follow-up to a separate study entitled "Qualitative Study about Value Cognition and Benefits of Consumer on Culture-Art Products". The current study aims to extend practical implications that enhance the effectiveness of marketing strategies among the producing and policy agencies in the industry. The purpose of this study is to investigate dimensions of value cognition, benefits and attributes of culture-art products, and identify the effects of consumer value cognition on benefits and attributes. The questionnaire was developed based on the conceptual structure of qualitative research and previous researches. It was composed of value cognition, benefits, attributes of culture-art products and demographic variables. This survey was conducted on-line and off-line among a total of 662 persons ranging from their teens to their 50's who were living in Seoul, Gyeonggi-do, various metropolitan cities, and small and medium-sized cities. The data collected was analyzed by factor analysis and path analysis using SPSS WIN 18.0 and AMOS 16.0. This empirical study found that the dimensions of value cognition of culture-art products were categorized into personal goods, aesthetic goods and public property. This shows that the consumers perceive culture-art products as products that are worthy enough to pay the costs not just for personal benefits but also for their social values. Also the formation of value cognition for culture-art products requires special conditions unlike that for physical consumer goods and services, which simply require marketing stimuli. The dimensions of benefits pursued by consuming culture-art products were found to be composed of four types - pursuit of aesthetic benefits, pursuit of actual benefits, pursuit of emotional benefits, and pursuit of conspicuous character. This result implies that people consume culture-art products not just to pursue pleasure from emotional and intelligent satisfaction as well as social relations, but also to seek the needs and benefits embodied at a social level. The dimensions of attributes of culture-art products had seven different factors, - environmental, price, evaluation, people, artwork, composition, and personal relations - which is plentiful. This is because the attributes of culture-art products are very complicated compared to other consumer goods or services. Since culture-art products include not just cultural or artistic works but also all physical, human, environmental, and systemic elements of the products in a comprehensive manner, consumers perceive everything they experience in the process of consuming culture-art products as part of the products. The dimensions of value cognition was found to affect attributes of the products, mostly using pursued benefits as a mediating factors. This result is consistent with the result of qualitative research, and proves that applying the means-end chain theory in the reverse direction is reasonable. The result can be interpreted that consumers' value cognitions for culture-art products turns into actual benefits leading to consumers' decisions. Furthermore, this result reveals that when consumers choose culture-art products, they take into account the attributes of culture-art products depending on the benefits they pursue. These results confirm that despite their conceptual and abstract attributes, culture-art products have values that contribute to actual benefits for individual consumers and society. Hence, value cognition generates benefits to be pursued and this in turn affects the consumers' choices of attributes on products. Based on the conceptual structure of consumers' value cognitions on culture-art products and its dimensions, it is possible to find detailed methods to provide opportunities for education and training to form and reinforce positive value cognition on culture-art products. And through those methods, it will be possible to develop attributes of culture-art products according to the dimensions of pursued benefits, and allow conceptual products become the subject to valuable consumption in real life. These results provide theoretical understanding of consumer behavior in culture marketing and useful information to culture-art producers, companies that use culture and art, and government agencies that use culture-art as a mean to improve the public perception of quality of life. As a follow up on this study, there should be experimental studies that can develop criteria visualizing the demands of consumers who purchase culture-art products and identify their detailed attributes. Studies that compare characteristics of different areas within the culture-art product category and in-depth studies on a specific area or genre will also be needed. In order to develop marketing strategies for culture-art products, studies on the formation and reinforcement of positive value cognition on culture-art products and education for the development of consumer demand as well as on the development and differentiation of attributes of culture-art products depending on types of consumer groups should also follow.

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