• Asia pacific journal of information systems
• /
• v.12 no.3
• /
• pp.213-233
• /
• 2002

Recently, a lot of companies intend to make spin-offs as the Internet usage is proliferating in the business area. A spin-off means a small but autonomous company which is thought to show higher profitability rather than it stays under the influence of a mother enterprise. To prove our hypotheses, we collected questionnaire data from 104 companies considering spin-offs. From experiments with Factor Analysis, we found that there exist four factors which decision-makers should consider before deciding spin-offs such as competence of unit, competence of mother company, competence of spin-off company, and support of mother company. After massive experiments with Regression Analysis we also found that there are significant three performance factors such as competence of unit, competence of spin-off company, and support of mother company. The survey also asked about three potential strategies that they may have been following for achieving business objectives: Cost leadership, Focus, and Differentiation, Six benefits factors emerged from this study: External competitiveness, Internal competency, Productivity, Change, Cost saving, and Improvement. External competitiveness was the most important benefit, and it predicted a Differentiation and Focus strategy. Productivity and Improvement also predicted a Differentiation strategy. External competitiveness, Change, and Cost saving predicted a Cost leadership strategy. However, organizations followed Differentiation and Focus strategies significantly more than Cost leadership. The assessment thus sheds light on the link between information strategy and spin off. We hope that based on our results, many companies considering a spin-off can make a right decision and expect higher performance in a turbulent business environment.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.9A
• /
• pp.853-866
• /
• 2008

In this paper, a multi-hop relaying transmission scheme is analyzed regarding its feasibility and potentiality in the IEEE 802.22-based cognitive radio (CR) environment. Shortly, basic design issues are addressed such as relay station (RS) deployment and a frame structure of physical channel to escape inter-hop interference. This paper mainly develops a radio resource management scheme based on spectrum sensing results aggregated from CR secondary nodes and improves the opportunistic spectrum sharing efficiency. In particular, a decision rule about a channel availability is made using a distributed sensing method. Subsequently, spectrum allocation and routing path decision procedures are proposed to establish a link from source to destination with a hop-by-hop manner. Simulation results show that the proposed multi-hop relaying scheme is substantially profitable in CR environments if the number of hops and RS deployment are designed in such a way that the spectrum sharing gain is larger than spectrum division loss which is inherently induced in multi-hop relaying systems.

• The Journal of the Korea Contents Association
• /
• v.8 no.12
• /
• pp.236-245
• /
• 2008

The cancer patient who leads Bone scan and the PET study from in the nuclear medical study what is enforced with the link of early detection and the time which spreads, it will be able to accomplish a positive treatment with the data which presumes that time it researches a degree as cancer discovery initially and only difference of final period the bay it knows. The patient who receives a cancer decision it will be able to accomplish the necessary defense it will be able to delay the time in order, the maximum control the possibility of doing will be becomes the judgement. Cancer decision to initially the nuclear study and treatment it will be in parallel with effort and the investment which are constant and the schedule hour will elapse and to after difficulty some the case which comes to be negligent will be frequent and it will appear with him there to be a possibility of knowing, it will be caused by and the transfer of the cancer sell will be activity. It has a treatment objective and are to each medical treatment agency against and the medical treatment agency worker it will be able to overlook is not the portion is the private plan which needs a more positive disposal, it does.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.46 no.12
• /
• pp.82-88
• /
• 2009

An adaptive cooperation system is considered with the cooperation decision strategy based on the differences between instantaneous signal-to-noise ratio (SNR) S-D and R-D channels. Specifically, if the quality of the direct link (S-D) is better than that of the link from the relay to the destination (R-D), the source will transmit to destination directly with all scheme's transmitted power. Otherwise, the source broadcasts the signal with a lower power in the first time slot. Then, in the second time slot, if the relay decodes its received signal correctly, it re-transmits the re-encoded signal to the destination else the source will transmit again with the remaining power. Firstly, the spectral efficiency is derived by calculating the probabilities of direct transmission and cooperation mode. Subsequently, the BER performance for the adaptive cooperation schemes is analyzed by considering the BER routine of each mode. Finally, the Monte-Carlo simulation results are presented to confirm the performance enhancement offered by the proposed schemes.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.8A
• /
• pp.1223-1230
• /
• 2000

In this paper, we proposed a handoff decision method based on signal-to-interference ratio(SIR) of the pilot channel in order to perform a handoff more effectively and to complement disadvantages - deterioration quality of a call, decreasing capacity of the system, and wasting power of the mobile station - which is caused when handoff is performed by the classical method that execute a handoff based on received signal strength. Moreover, when we change that the minimum threshold, the cell loading which is defined active traffic channels to total traffic channels ratio, and the fraction of the transmit power from base station allocated to the pilot channel on the forward link of a DS-CDMA system, we analyzed mean numbers of handoff depending on hysteresis level during the mobile station moving from one base station to another base station.

• Journal of Navigation and Port Research
• /
• v.44 no.4
• /
• pp.354-361
• /
• 2020

The term "articles for ship" is a general term for all relevant mechanical accessories (SPARE) and consumable materials (STORE) commonly used in ships. Ships commonly are at sea, so it is difficult to respond rapidly to the demand for them in an emergency situation. In particular, it is more difficult to determine the boarding location of tramper ships as it is more difficult to predict the next sailing route in advance. The purpose of this study was to identify the important factors to be considered in determining the boarding location of tramper ships through a survey of each ship owner and ship management company. This valuable information on the proposed supply procedures for each country and port, would be an efficient way to supply articles for ships.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.5
• /
• pp.1992-2008
• /
• 2018

Mobile opportunistic network is a kind of ad hoc networks, which implements the multi-hop routing communication with the help of contact opportunity brought about by the mobility of the nodes. It always uses opportunistic data transmission mode based on store-carry-forward to solve intermittent connect problem of link. Although many routing schemes have been proposed, most of them adopt the greedy transmission mode to pursue a higher delivery efficient, which result in unfairness extremely among nodes. While, this issue has not been paid enough attention up to now. In this paper, we analyzed the main factors that reflect fairness among nodes, modeled routing selection as a multiple attribute decision making problem, and proposed our Fairness-aware Routing Strategy, named FARS. To evaluate the performance of our FARS, extensive simulations and analysis have been done based on a real-life dataset and a synthetic dataset, respectively. The results show that, compared with other existing protocols, our FARS can greatly improve the fairness of the nodes when ensuring the overall delivery performance of the network.

• The Journal of Asian Finance, Economics and Business
• /
• v.7 no.5
• /
• pp.237-248
• /
• 2020

The purpose of this study is to investigate and reconfirm the research instruments and variables that have been developed by prior study and built new concepts from empirical research results. Besides analyzing the essential role of fundamental, rational, and psychology aspects to increase employee's intention to stay in a company, which is useful for the development of human resource development strategies for millennial workers in the future. A total of 438 non-student male respondents aged 23-36 years, with unmarried status and not working in the SOE sector or as a civil servant, were surveyed with questionnaires. The study was conducted in Makassar, Indonesia. Data collection uses a survey with the second-order model approach and regression with control variables. The findings of this study suggest the existence of an inter-relationship between fundamental, rational and psychological aspects. They are inseparable and have a positive and significant influence. Broadly speaking, the link between fundamental, psychology and rational aspects states that the decision for millennial male workers to stay in the company will depend on whether the company has a good image and reputation, the level of attention the organization pays to career development, is competent, and applies regulations and rules with flexibility.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.5
• /
• pp.2029-2043
• /
• 2018

In this paper, we propose a novel inter-cell handover approach from a new perspective in dense Heterogeneous and Small Cell Networks (HetSNets). We first devise a cell selection mechanism to choose a proper candidate small cell for the UEs that tend to implement inter-small cell handover (ICH). By exploiting the property of a typical non-concentric circle, i.e., circle of Apollonius, we then propose a novel analytical method for modeling inter-cell handover regions and present mathematical derivation to prove that the inter-small cell handover issues fit the property of the circle of Apollonius. We design an inter-cell handover algorithm (ICHA) by means of our proposed handover model to dynamically configure hysteresis margin and properly implement handover decision in terms of UE's mobility. Simulation results demonstrate that the proposed ICHA yields lower call drop rate and radio link failure rate than the conventional methods and hence achieve high Handover Performance Indicator (HPI).

• Journal of Intelligence and Information Systems
• /
• v.27 no.4
• /
• pp.73-95
• /
• 2021

This study uses Node2vec graph embedding method and Light GBM link prediction to explore undeveloped export candidate countries in Korea's food and beverage industry. Node2vec is the method that improves the limit of the structural equivalence representation of the network, which is known to be relatively weak compared to the existing link prediction method based on the number of common neighbors of the network. Therefore, the method is known to show excellent performance in both community detection and structural equivalence of the network. The vector value obtained by embedding the network in this way operates under the condition of a constant length from an arbitrarily designated starting point node. Therefore, it has the advantage that it is easy to apply the sequence of nodes as an input value to the model for downstream tasks such as Logistic Regression, Support Vector Machine, and Random Forest. Based on these features of the Node2vec graph embedding method, this study applied the above method to the international trade information of the Korean food and beverage industry. Through this, we intend to contribute to creating the effect of extensive margin diversification in Korea in the global value chain relationship of the industry. The optimal predictive model derived from the results of this study recorded a precision of 0.95 and a recall of 0.79, and an F1 score of 0.86, showing excellent performance. This performance was shown to be superior to that of the binary classifier based on Logistic Regression set as the baseline model. In the baseline model, a precision of 0.95 and a recall of 0.73 were recorded, and an F1 score of 0.83 was recorded. In addition, the light GBM-based optimal prediction model derived from this study showed superior performance than the link prediction model of previous studies, which is set as a benchmarking model in this study. The predictive model of the previous study recorded only a recall rate of 0.75, but the proposed model of this study showed better performance which recall rate is 0.79. The difference in the performance of the prediction results between benchmarking model and this study model is due to the model learning strategy. In this study, groups were classified by the trade value scale, and prediction models were trained differently for these groups. Specific methods are (1) a method of randomly masking and learning a model for all trades without setting specific conditions for trade value, (2) arbitrarily masking a part of the trades with an average trade value or higher and using the model method, and (3) a method of arbitrarily masking some of the trades with the top 25% or higher trade value and learning the model. As a result of the experiment, it was confirmed that the performance of the model trained by randomly masking some of the trades with the above-average trade value in this method was the best and appeared stably. It was found that most of the results of potential export candidates for Korea derived through the above model appeared appropriate through additional investigation. Combining the above, this study could suggest the practical utility of the link prediction method applying Node2vec and Light GBM. In addition, useful implications could be derived for weight update strategies that can perform better link prediction while training the model. On the other hand, this study also has policy utility because it is applied to trade transactions that have not been performed much in the research related to link prediction based on graph embedding. The results of this study support a rapid response to changes in the global value chain such as the recent US-China trade conflict or Japan's export regulations, and I think that it has sufficient usefulness as a tool for policy decision-making.