• Journal of electromagnetic engineering and science
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• v.9 no.1
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• pp.17-24
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• 2009

In recent years, OFDMA(orthogonal frequency division multiple access) and SC-FDMA(Single Carrier Frequency Division Multiple Access) have been widely studied for the uplink of a mobile communication system. In this paper, PAPR(Peak-to-Average Power Ratio) and BER(Bit Error Rate) performance of the OFDMA and SC-FDMA systems are studied in relation to the uplink of a mobile communication system. Three kinds of sub-carrier allocation methods in the OFDMA system and 2 kinds of sub-carrier allocation methods in SC-FDMA system are suggested to compare and improve system performance. Simulation results show that in the OFDMA system, the first sub-band allocation method has better PAPR reduction performance than the other methods. In the SC-FDMA system, the distributed allocation method offers similar P APR, compared with the sub-band allocation method. P APR can be further reduced by adding a spectrum shaping filter with an appropriate roll of factor. Furthermore, it is found that on average, SC-FDMA can reduce the PAPR by more than 5 dB compared to OFDMA, when the total sub-carrier number is 1,024 and the sub-carrier number allocated to each user changes trom 8 to 512. Because of the frequency diversity and low PAPR characteristics, SC-FDMA system of the distributed sub-carrier allocation method can achieve better BER performance than the OFDMA system.

• Korean Journal of Optics and Photonics
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• v.17 no.5
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• pp.475-479
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• 2006

An integrated photonic K-band microwave bandpass filter has been proposed and demonstrated by incorporating a polymeric ring resonator. Its transfer characteristics were adjusted by shilling the resonance wavelength of the ring resonator via the thermooptic effect. The achieved performance of the filter includes the center frequency of 20 GHz, the attenuation of ${\sim}15dB$, the bandwidth of 2 GHz, and the corresponding quality factor of 10. The microwave output power within the passband of the device was adjusted at the rate of about 6.7 dB/mW in the range of 27 dB. This kind of device with electrically controllable transfer characteristics can be applied to implement microwave switches and other devices.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.595-604
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• 2021

For civil servants in the legal sector, the best performance that must be shown is not how they carry out activities following standard operational procedures but what is more important is how they show Organizational Citizenship Behavior (OCB) in daily activities. This study aims to examine what factors influence the formation of OCB civil servants in the legal sector in Indonesia. The study was conducted on 145 civil servant respondents who were involved in secretarial activities, each from the Judicial Commission Secretariat, the Attorney General's Office, the Ministry of Justice, the Supreme Court, the Police Headquarters, and the Constitutional Court. The research methodology used Partial Least Square (PLS) Version 3.0. The empirical findings of the research show that organizational culture has a significant influence in shaping transformational leadership that can build OCB among civil servants in Indonesia. This effect is much larger and more significant than the compensation system, which is widely believed to be the main factor in forming OCB, such as the results of previous studies. The results of this study imply that the formation of an organizational culture with values that can create high work productivity which has an impact on transformational leadership styles in building OCB.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.4
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• pp.101-115
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• 2020

It is very important for companies to form a strong brand resonance to maximize profits, attract new customers, and prevent them from leaving existing customers. In this study, we examined the relationship between brand awareness factors and brand attachment leading to brand identity cognition, brand performance, and brand emotion, and verified how brand attachment plays a role in shaping brand resonance. As a result, it was confirmed that brand emotion among brand awareness factors is a key factor affecting brand attachment and forming brand resonance. In addition, if the perception of brand identity is established until the true brand resonance of consumers is established, they will experience the true value of the brand through differential performance on the brand, and further increase the emotional response of consumers. This led to deep solidarity with the brand and consumers through attachment to the brand, interacting with the brand and showing high brand empathy behavior.

• Korean Journal of Comparative Education
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• v.28 no.2
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• pp.23-52
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• 2018

This study examines factors that influence adolescents' political trust in Asian societies with special emphases on authoritarian orientations and corruption perception. Previous studies on adolescents' political trust have focused almost exclusively on Western societies. As a result, the impact of other cultural values that are specific to Asian societies, such as authoritarian orientations, on adolescents' political trust has received little attention in the existing literature. Moreover, situated within a socialization framework which argues that political trust is an extension of interpersonal trust, much prior work has ignored the role of adolescent evaluations of institutional performance in generating political trust. The data I use offer empirical evidence that both authoritarian orientations and institutional performance-especially its ability to curb corruption-are independent sources of political trust among Asian adolescents and that the trust-eroding effect of corruption is less salient among Asian adolescents adopting more authoritarian orientations. Additionally, the evidence also suggests that corruption perception is a more important factor than authoritarian orientations in shaping adolescents' political trust in more economically developed countries while the reverse pattern is found in less developed countries.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.37 no.1
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• pp.76-87
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• 2000

Multicarrier DS-CDAM is an effective approach to realize wideband CDMA system in a multipath fading channeal. In this paper, we propose a cinvolutionally-coded overlapped multicarrier DS-CDMA system, and show the performance improvement by comparing with conventional multicarrier DS-CDMA system. We consider the case of 50% overlapping with the adjacent subband to utilize the transmission bandwidth more efficiently. In the proposed multicarrier system, each of the rate 1/M convolutionally-encoded symbols is also 1/R repetition coded and transmitted using overlapped multicarriers and we may obtain the coding gain and frequency diversity effect, simultaneously. We also analyze the possibility of reduction in total MUI by considering a raised-cosine wave-shaping filter having a roll-off factor (0< ${\beta}{\le}1$). It will be shown that the proposed system outperforms the multicarrier DS-CDMA system in $^{[3]}$.

• Journal of Preventive Medicine and Public Health
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• v.10 no.1
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• pp.34-43
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• 1977

This study attempts to examine the performances of Myun Health Workers-the frontline workers in the Korean rural health care delivery system. The time-activity approach was mainly utilized as a measuring tool. This study was undertaken in September 1976 with 35 Myun Health Workers at the Kang Wha County. The pretested time-activity approach sheets were filled out daily for one month by those Myun Health Workers themselves. Statistical means and variances of analysis were utilized for statistical method in comparing some activities and functions converged into time distribution Findings: 1. The workers's average working hours derived in this study is 8 hours and 48 minutes per day, which takes half an hour longer than normal schedule. 2. They spend 56% working hour for direct services, in other words, the main function, 22% for supportive function, and 22% for other activities, the unrelated health services. 3. Considering the total working hours of main function, out-center activity is far more than in-center services with the ratio of 70% to 30% respectively, which proves, therefore, that the main activity of the workers is home visiting. 4. It takes 20 minutes purely for home visiting and takes 14 minutes for transportation. 5. This research also indicates that such factors as characteristics of the health workers and myun influence in shaping the structures of the worker's function and activity: a. The workers whose working site is located in myun office spend 15% among total working hours in carring out official myun activities, which is incidentally unrelated to health services, while the health subcenter have no rooms for administrative jobs for myun office. b. The workers whose office is in health subcenter contribute much time in doing main function and those working in special project distribute more time in performing supportive function. c. The types of workers are another dominant factor to influence the components of worker's functions and activities. MCH workers and MPW I spend much time for manipulating main function. d. MPW II, whose function is reorganized by special project in 2 myuns shows different pattern of time distribution compared to the TB worker orFP worker in the ordinary area. MPW II distributes their time evenly in performing MCH program, T.B. Program, F.P. program and education activity, while the unipurpose workers engage in carring out only their dominant role. e. Another variables which involve the variation of the worker's activity can be illustrated with the variables like target population, size of myun and convenience for transportation, among which the latter two are remarkable factors in determining the time for out-center service.