• ETRI Journal
• /
• v.35 no.4
• /
• pp.706-709
• /
• 2013

As an alternative to the traditional pilot-aided orthogonal frequency division multiplexing (OFDM), the time-domain pseudonoise (PN)-padded OFDM provides a higher spectral efficiency. However, the carrier frequency offset (CFO) attenuates peaks of the conventional PN correlation output, which limits the CFO estimation range of the OFDM synchronizer. An improved correlation is proposed in this letter to remove the CFO-induced amplitude attenuation of correlation peaks. For a synchronizer adopting the designed correlator, a larger range of CFO acquisition is obtained through using wider correlation windows with a smaller interval between them. The proposed method of CFO acquisition is verified in a digital terrestrial multimedia broadcast receiver, in which the synchronizer is able to acquire CFOs up to ${\pm}320$ kHz in the DVB-T F1 channel. Furthermore, the acquisition range can be expanded in more favorable channels.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.10 no.3
• /
• pp.85-97
• /
• 2015

This study examined the effects of outside directors and CEO duality on acquisition strategies and performance of Korean firms in high-technology industry. Based on the resource dependence theory, we focused on the service and resource-dependence roles from board of directors in the process of decision-making of acquisition strategies. In addition, CEO opportunism behavior rises when CEO serves as chairperson of board and induces the negative effects on acquisition performance. Specifically, we investigated the interaction effects between outside directors ratio and CEO duality. For the period of 2004 to 2012, 246 acquisitions of Korean firms in high-technology industry were analyzed to test our intended hypotheses. Our results indicate that there exist positive relationship between outside director ratio and acquisition performance for Korean high-technology firms. Negative associations prevail between CEO duality and performance consequences of acquisitions. While outside director ratio has a positive effect on acquisition performance when there is a presence of CEO duality, negative effect prevail for outside director ratio on acquisition performance in the absence of CEO duality position to hold our interaction hypothesis. The favor of dual structure can be explained with implications referring to unity of command and strong leadership driven from CEO duality that enhances the resource dependence roles of board of directors in the context of high-technology industry acquisition behaviors rendered by Korean firms.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38A no.5
• /
• pp.416-425
• /
• 2013

A hybrid PN code phase acquisition system based on a least-mean-square adaptive filter, interpreted as a channel estimator is proposed and analyzed for direct-sequence spread-spectrum systems under frequency selective Rayleigh fading channels. Closed form expressions are derived for the filter tap weights and detection/false alarm probabilities. Compared to previously proposed systems, the proposed system achieves smaller mean acquisition times, is more robust to the operating signal-to-noise ratio and allows for multiplication free tap weight updates.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.19 no.2
• /
• pp.21-43
• /
• 1994

Software acquisition involves purchase of new technology as well as the product itself. Consequently, evaluation of candidate packages or development contractors requires formal models that can objectively compare the candidates' technological characteristics with respect to user requirements. This paper proposes three technological evaluation models for software acquisition : 1) a structural model dthat organizes the technological factors to be evaluated, 2) a scoring model that quantifies the candidates' technological values, and 3) an organization model that orgnizes and assigns responsibilities to technical evaluators. Three models, initially built on expert surveys and later refined through interviews with opinion leaders, are primarily intended for governmental use : the Korean government is expected to use these models as the software acquisition standards starting in 1994.

• Journal of Information Management
• /
• v.32 no.3_4
• /
• pp.31-42
• /
• 2001

Research libraries, facing the difficulties in building sufficient collections to meet the various users, have implemented various cooperative acquisition programs. In recent years, Internet and other information technology enables more effective and efficient cooperation among research libraries. This paper reviews the methods and cases of cooperative acquisitions among research libraries, including CRL, OhioLINK, RLG Conspectus, TRLN Discussing the backgrounds and related issues. several strategies were suggested for the continuous implementation for cooperative acquisition.

• ETRI Journal
• /
• v.30 no.4
• /
• pp.495-505
• /
• 2008

This paper presents a parallel processing searcher structure for the initial synchronization of a direct sequence ultra-wideband (DS-UWB) system, which is suitable for the digital implementation of baseband functionalities with a 1.32 Gsample/s chip rate analog-to-digital converter. An initial timing acquisition algorithm and a data demodulation method are also studied. The proposed searcher effectively acquires initial symbol and frame timing during the preamble transmission period. A hardware efficient receiver structure using 24 parallel digital correlators for binary phase-shift keying DS-UWB transmission is presented. The proposed correlator structure operating at 55 MHz is shared for correlation operations in a searcher, a channel estimator, and the demodulator of a RAKE receiver. We also present a pseudo-random noise sequence generated with a primitive polynomial, $1+x^2+x^5$, for packet detection, automatic gain control, and initial timing acquisition. Simulation results show that the performance of the proposed parallel processing searcher employing the presented pseudo-random noise sequence outperforms that employing a preamble sequence in the IEEE 802.15.3a DS-UWB proposal.

• International Journal of Advanced Culture Technology
• /
• v.9 no.4
• /
• pp.118-125
• /
• 2021

This study's purpose is to examine the effects of mobile apps on learners' vocabulary acquisition and to analyze students' perceptions and opinions about the vocabulary app. To this end, this study set up a control group, which was given explicit instructions in the classroom by the instructor and an experimental group, which used a vocabulary app. The vocabulary acquisition test results suggested that the difference between the the two groups was insignificant. However, user satisfaction with regard to the mobile app was high, and the reasons given were the following: convenience, efficiency of memorizing, having fun while learning, and the app's interface. Based on these results, this study suggests that teachers should use mobile apps much more actively in classroom instruction, and encourge students to let apps play a more active role in their language studies.

• Asia pacific journal of information systems
• /
• v.30 no.4
• /
• pp.879-918
• /
• 2020

One of the challenges faced by Talent Acquisition teams today pertains to the acquisition of human resources by matching job descriptions and skillsets desired. It is more so in the case of competitive sectors like the Indian IT sector. There can be various channels for Talent Acquisition and accordingly, the cost and benefits might vary. However, the consequences of a mismatch have an impact on the quality of deliverables, high recruitment expenses and loss of revenue for the organization. With increased and diverse sources of data that are available to organizations today, there is ample opportunity to apply analytics for informed decision making in this field. This paper reveals useful insights that help streamline the Talent Acquisition process in the Indian IT Industry. The paper adopts a data-centric approach to examine the critical determinants for efficient and effective Talent Acquisition process in IT organizations. Selected supervised machine learning algorithms are applied for the analysis of the dataset. The study is likely to help organizations in reassessing their talent acquisition strategy with respect to key parameters like expected cost to company (CTC), candidate sourcing channels and optimal joining period.

• Journal of Information Science Theory and Practice
• /
• v.10 no.3
• /
• pp.24-39
• /
• 2022

Online learning is becoming ubiquitous worldwide because of its accessibility anytime and from anywhere. However, it cannot be successfully implemented without understanding constructs that may affect its adoption. Unlike previous literature, this research extends the Unified Theory of Acceptance and Use of Technology with three well-known theories, namely compatibility, online self-efficacy, and knowledge sharing and acquisition to examine online learning adoption. A total of 264 higher education students took part in this research. Partial Least Squares-Structural Equation Modeling was used to evaluate the proposed theoretical model. The findings suggested that performance expectancy and compatibility were significant predictors of behavioral intention, whereas behavioral intention, facilitating conditions, and compatibility had a significant and direct effect on online learning's actual use. The results also showed that knowledge acquisition, knowledge sharing, and online self-efficacy were determinates of performance expectancy. Finally, online self-efficacy was a predictor of effort expectancy. The proposed model achieved a high fit and explained 47.7%, 75.1%, 76.1%, and 71.8% of the variance of effort expectancy, performance expectancy, behavioral intention, and online learning actual use, respectively. This study has many theoretical and practical implications that have been discussed for further research.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.46 no.4
• /
• pp.304-311
• /
• 2023

The 4th Industrial Revolution and the continuous development of Science and Technology have also required a speedy business promotion method in the defense industry. Advanced countries including the United States are already boldly innovating the existing high-cost and long-term acquisition system with the highest priority in weapons development to cope with the military rise of Russia and China. The Ministry of National Defense and the Defense Acquisition Program Administration have also recently introduced a quick acquisition system and are applying it to business promotion. In addition, some small-scale projects and weapons systems are being reorganized so that they can be managed by the units demanding them. After an organizational diagnosis of the Project Acquisition Group by the Ministry of National Defense in 2020, it has been reassigned as a subordinate unit of the Army Logistics Command from a direct unit managed by the Army HQ. As a result, problems such as work conflict or redundancy have been identified. In addition, a system has been implemented to shorten the acquisition period by applying a rapid acquisition program in the field of weapons systems by benchmarking the rapid acquisition program of advanced countries. The force support system project process will also need to introduce such a quick acquisition system. In addition, the Ministry of National Defense is considering ways to delegate some weapon systems to each military, which will then carry out tasks ranging from requirements determination to project management. Accordingly, it is now time to expand the organization for the management of the Army's weapons system acquisition project. Therefore, in this paper, the Army Project Acquisition Group was analyzed on its organization, acquisition procedures, and cooperation systems, with presentations of development plans for each field.