• Journal of Korean Society of Industrial and Systems Engineering
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• v.47 no.2
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• pp.40-47
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• 2024

As environmental concerns escalate, the increase in recycling of aluminum scrap is notable within the aluminum alloy production sector. Precise control of essential components such as Al, Cu, and Si is crucial in aluminum alloy production. However, recycled metal products comprise various metal components, leading to inherent uncertainty in component concentrations. Thus, meticulous determination of input quantities of recycled metal products is necessary to adjust the composition ratio of components. This study proposes a stable input determination heuristic algorithm considering the uncertainty arising from utilizing recycled metal products. The objective is to minimize total costs while satisfying the desired component ratio in aluminum manufacturing processes. The proposed algorithm is designed to handle increased complexity due to introduced uncertainty. Validation of the proposed heuristic algorithm's effectiveness is conducted by comparing its performance with an algorithm mimicking the input determination method used in the field. The proposed heuristic algorithm demonstrates superior results compared to the field-mimicking algorithm and is anticipated to serve as a useful tool for decision-making in realistic scenarios.

• Journal of the Korean Operations Research and Management Science Society
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• v.41 no.2
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• pp.1-16
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• 2016

Yield management, which originated from the U.S. service industry, uses pricing techniques and information systems to make demand management decisions. Demand uncertainty is an important factor in the area of demand management. A key strategy to reduce the effects of demand uncertainty is substitution. The most generally known type of substitution is inventory-driven substitution, in which consumers substitute an out-of-stock product by buying a similar or other type of product. Another type of substitution is the price-driven substitution, which occurs as a result of price changes. In this research, we consider two market segments that have unique perishable products. We develop yield management optimization models with stochastic demand based on the newsvendor model where inventory-driven and price-driven substitutions are allowed between products in the two market segments. The most significant contribution of this research is that it develops analytical procedures to determine optimal solutions and considers both types of substitution. We also provide detailed theoretical analysis and numerical examples.

• Asia pacific journal of information systems
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• v.16 no.3
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• pp.95-116
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• 2006

Although the study of post-adoption has increased in recent years, few studies have focused on the moderating effect of uncertainty avoidance on the relationship between post-expectation and behavior. The purpose of this study is to examine the moderating effect of uncertainty avoidance in the mobile Internet domains. This study proposed a post-adoption model based on prior continuance model. This theoretical model was verified empirically by conducting web surveys and multi-group analysis. Based on the survey data, we classified users into those with high uncertainty avoidance and those with low uncertainty avoidance. The results indicate that post expectations have significant impacts on satisfaction and continuance intention. The results also show that the impacts of intrinsic motivational factors of mobile Internet services on satisfaction and continuance intention are stronger for users with high uncertainty avoidance. On the other hand, the impacts of extrinsic motivational factors on satisfaction and continuance intention are stronger for users with low uncertainty avoidance, with a few exceptions. This paper ends with theoretical and managerial implications of the study results, as well as limitations and future research directions.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.9
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• pp.263-269
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• 2022

The global financial crisis of 2008-2009 and the COVID-19 pandemic that started in 2019 along with the slow and unstable recovery of the global economy have raised concerns about the impact of global uncertainty on the macroeconomics of the countries. The paper used the Structural Vector Autoregression (SVAR) model to examine the impact of global uncertainty shocks on Vietnam's economy from the period 2008-2022. We found that Vietnam's output dropped following the shock of global uncertainty, the peak was in the third month, and lasted for one year. Inflation in Vietnam had a rapid downturn in the first month, peaked in the seventh month, and took a long time to cease. When the economy experienced the shock of increased global uncertainty, Vietnam's policy interest rate was adjusted downward. Additionally, we included a long-term interest rate to consider the overall impact of monetary policy into account. A decreasing trend was also found with this rate. The global uncertainty shock effects acted as the aggregate demand shocks, reducing output and inflation as the uncertainty increases and vice versa, thus monetary policy can be used to regulate Vietnam's economy to deal with negative shocks without the trade-offs between output and inflation as aggregate supply shocks.

• Journal of the Korea Society of Computer and Information
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• v.18 no.9
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• pp.111-120
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• 2013

Uncertainty in Context-aware computing is mainly a consequence of the complexity of context acquisition mechanisms and context processing. The presence of uncertainty may harm the users' confidence in the application, rendering it useless. This paper describes a three-phase strategy to manage uncertainty by identifying its possible sources, representing uncertain information, and determining how to proceed, once uncertain context is detected. The level of effort that is necessary to eliminate the uncertainty of context information affects the reliability of the system, because Sensor network system have no intervention of humans. In this paper, We applied proposed method to the development for the sensor network system, Uncertainty management can be applied a part of the system development life-cycle. It confirmed that result of testing show that detection performance is stable.

• Journal of the Korean Society for information Management
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• v.36 no.2
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• pp.175-199
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• 2019

Uncertainty means incomplete stages of knowledge of propositions due to the lack of consensus of information and existing knowledge. As the amount of academic literature increases exponentially over time, new knowledge is discovered as research develops. Although the flow of time may be an important factor to identify patterns of uncertainty in scientific knowledge, existing studies have only identified the nature of uncertainty based on the frequency in a particular discipline, and they did not take into consideration of the flow of time. Therefore, in this study, we identify and analyze the uncertainty words that indicate uncertainty in the scientific literature and investigate the stream of knowledge. We examine the pattern of biomedical knowledge such as representative entity pairs, predicate types, and entities over time. We also perform the significance testing using linear regression analysis. Seven pairs out of 17 entity pairs show the significant decrease pattern statistically and all 10 representative predicates decrease significantly over time. We analyze the relative importance of representative entities by year and identify entities that display a significant rising and falling pattern.

• Industrial Engineering and Management Systems
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• v.11 no.2
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• pp.176-182
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• 2012

This paper presents a new approach to risk comparison in uncertain environment. Based on the uncertainty theory, some uncertain risk measures and risk comparison rules are proposed. Afterward the bridges are built between uncertain risk measures and risk comparison rules. Finally, several comparable examples are given.

• Journal of Information Technology Applications and Management
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• v.15 no.1
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• pp.43-65
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• 2008

This study investigates the effects of business environment on the e-business strategy and performance of venture firms. The development of the research model is based on the empirical studies on the strategy literature. The data from the survey was analyzed using Partial Least Squares(PLS). For Daedeok Valley Venture Firms, product innovation differentiation strategy is affected by environmental uncertainty. And, cost leadership strategy tend to be influence by environmental uncertainty. Finally, venture firm's performance is effected by cost leadership strategy and marketing differentiation strategy. However, for in Hsinchu Science Park Venture Firms, product innovation differentiation strategy is affected by environmental uncertainty and heterogeneity. And, marketing differentiation strategy is enhanced by environment uncertainty and industry growth. In addition, cost leadership strategy tend to be influence by environmental uncertainty and heterogeneity. Finally, venture firm's performance is effected by cost leadership strategy and product innovation differentiation strategy.

• Journal of Technology Innovation
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• v.8 no.1
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• pp.155-172
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• 2000

Management control is the process by which managers ensure that resources are obtained and used effectively and efficiently in achieving the organization's objectives. This paper explores relationships between characteristics of R&D and management control. R&D characteristics measured in this research include the degree of technological uncertainty and the measurability of outputs. Management control was classified and categorized into observable dimensions of control such as behavior, budget, process, results and personnel control. The relationships were tested with questionnaire survey data from a sample of 206 principal investigators(PIs) in the thirteen Government supported research institutes(GSRIs) in Korea. There are significant negative relations between the degree of technological uncertainty and budget, process and personnel control, and significant positive relations between the measurability of outputs and process, results and personnel control. These results indicate that the relations between task characteristics and management control in R&D are different from those to be found in other activities of organizations.

• Journal of the Korean Society of Systems Engineering
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• v.12 no.2
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• pp.19-27
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• 2016

Many countries concentrated on the space developments to enhance the national security and the people's quality of life. A space launch vehicle for accessing the space is a typical large complex system that is composed of the high-technology like high-performance, high-reliability, superhigh-pressure, etc. The project developing large complex system like space launcher is mostly conducted in the uncertain environment. To achieve a goal of the project, its success probability should be enhanced consistently by reducing its uncertainty during the life cycle: it's possible to reduce the project's uncertainty by performing the risk management (RM) that is a method for identifying and tracing potential risk factors in order to eliminate the risks of the project. In this paper, we introduce the risk management (RM) process applied for a Space Launch Vehicle R&D Project.