• Journal of Korean Society of Industrial and Systems Engineering
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• v.14 no.23
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• pp.19-25
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• 1991

In this paper, constrained resource project scheduling problems schedule project activities subject to finite constraints on the availability of non-storable resource. Further, resources are assumed to be available per period in constant amounts, and are also demanded by an activity in constant amounts throughout the duration of the activity. We describe formulation which minimizes the combined cost of fluctuations in resource demand and delay of project completion. Cost bounding procedures are augmented by dominance relationships presented as theorems. This paper presents algorithm for solving the problem. And numerical examples are presented. Sensitivity analysis to evaluate the effect of changes of cost efficients is conducted.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1396-1414
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• 2018

With the proliferation of the Internet of Things (IoT) healthcare devices, significant interoperability issue arises where devices use proprietary data transfer protocols. The IHE PCD-01 standard has been suggested for the exchange of healthcare data in ISO/IEEE 11073 PHD data model. However, the PCD-01 is not efficient to be used in the IoT environment. This is because the use of SOAP for PCD-01 may be too complex to be implemented in the resource-constrained IoT healthcare devices. In this paper, we have designed a communication system to implement ISO/IEEE 11073 and IHE PCD-01 integration using the IETF CoAP. More specifically, we have designed the architecture and procedures, using CoAP, to seamlessly transmit the bio-signal from the tiny resource-constrained IoT healthcare devices to the server in a standardized way. We have also built the agent, gateway, and PCD-01 interface at the server, all of which are using the CoAP as a communication protocol. In order to evaluate the performance of the proposed system, we have used the PCD data to be transmitted over CoAP, MQTT, and HTTP. The evaluation of the system performance shows that the use of CoAP results in faster transaction and lesser cost than other protocols, with less battery power consumption.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.45 no.5
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• pp.155-161
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• 2008

An automated healthcare monitoring is demand of time, lot of problems occurring just because of less monitoring of patients health condition on time. In this paper an embedded healthcare service is proposed by an iSCSI protocol on an automated multi-agent coordination by resource-constrained devices controlled system for healthcare service. The coordination between the resource constrained devices (e.g. PDA, SmartPhone, Tablet PC), and automated agents are maintained by a two-way handshaking mode iSCSI protocol. The automated health care control could be useable, and beneficial in the repetitive way. A fully centralized control is not applicable for this kind of approach.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.1
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• pp.39-44
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• 2005

Scheduling for digital system synthesis is assigning each operation in a control/data flow graph(CDFG) to a specific control step without violating precedence relation. It is one of the most important tasks due to its direct influence on the performance of the hardware synthesized. In this paper, we propose a resource-constrained scheduling algorithm. Our algorithm first analyzes the given CDFG to determine the number of functional units of each type, then assigns each operation to a control step while satisfying the constraints. It also tries to improve the solution iteratively by adjusting the number of functional units using the results collected from the previous scheduling. Experiments were performed to test the performance of the proposed algorithm, and results are presented

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.8
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• pp.4006-4024
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• 2017

Internet of Things (IoT) will transform our daily life by making different aspects of life smart like smart home, smart workplace, smart health and smart city etc. IoT is based on network of physical objects equipped with sensors and actuators that can gather and share data with other objects or humans. Secure communication is required for successful working of IoT. In this paper, a total of 13 lightweight cryptographic algorithms are evaluated based on their implementation results on 8-bit, 16-bit, and 32-bit microcontrollers and their appropriateness is examined for resource-constrained scenarios like IoT. These algorithms are analysed by dissecting them into their logical and structural elements. This paper tries to investigate the relationships between the structural elements of an algorithm and its performance. Association rule mining is used to find association patterns among the constituent elements of the selected ciphers and their performance. Interesting results are found on the type of element used to improve the cipher in terms of code size, RAM requirement and execution time. This paper will serve as a guideline for cryptographic designers to design improved ciphers for resource constrained environments like IoT.

• Journal of Korea Water Resources Association
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• v.42 no.4
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• pp.281-295
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• 2009

This study estimates the value of irrigation water in Korea using an economic programming model that is constructed with all the resource endowment constraints, technology restrictions and policy variables. The variability and uncertainty of water resource endowment are incorporated into the model through the chance-constrained technique. Solving the profit maximization problems with gradually reduced water endowments, we derive a series of shadow values of irrigation water. It has been found that uncertainty in water supply raises the damage from water loss, and the marginal damage increases in water loss.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.1-6
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• 2015

The IoT(Internet of things) technology enable objects around user to be connected with each other for sharing information. To support security is the mandatory requirement in IoT because it is related to the disclosure of private information but also directly related to the human safety. However, it is difficult to apply traditional security mechanism into lightweight devices. This is owing to the fact that many IoT devices are generally resource constrained and powered by battery. PSK(Pre-Shared Key) based approach, which share secret key in advance between communication entities thereafter operate security functions, is suitable for light-weight device. That is because PSK is costly efficient than a session key establishment approach based on public key algorithm. However, how to safely set a PSK of the lightweight device in advance is a difficult issue because input/output interfaces such as keyboard or display are constrained in general lightweight devices. To solve the problem, we propose and develop a secure PSK configuration scheme for resource constrained devices in IoT.

• Environmental and Resource Economics Review
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• v.20 no.2
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• pp.167-198
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• 2011

The Korean government recently announced greenhouse gases (GHG) emissions reduction target as 30% of 2020 business as usual (BAU) emission projection. As carbon emissions trading is widely used to achieve reductions in the emissions of pollutants, this study deals with the sectoral allocation of initial carbon emission permits in Korea. This research tests the effectiveness of a variety of allocation rules based on the bankruptcy problem in cooperative game theory and hybrid input-output tables which combines environmental statistics with input-output tables. The impact of initial emission permits allocation on economic growth is also analyzed through green growth accounting. According to the analysis result, annual GDP growth rate of Korea is expected to be 4.03%, 4.23%, and 3.67% under Proportional, Constrained Equal Awards, and Constrained Equal Losses rules, respectively. These rates are approximately from 0.69% points to 0.13% points lower than the growth rate of 4.36% without compulsory $CO_2$ reduction. Thus, CEA rule is the most favorable in terms of GDP growth. This study confirms the importance of industry level study on the carbon reduction plan and initial carbon emission permits should reflect the characteristic of each industry.

• IE interfaces
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• v.16 no.3
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• pp.332-343
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• 2003

This paper deals with pre-erection scheduling and erection scheduling in shipbuilding. Among shipbuilding scheduling, the ship erection scheduling in a dock is one of the most important since the dock is the most critical resource in a shipyard. However, it is more reasonable to consider pre-erection scheduling and erection scheduling as unified because they compete with the common constrained resources such as labor, crane, space, and so on. It is very hard to consider two scheduling problems simultaneously, and hence, we approach them sequentially. At first, we propose space resource leveling heuristics in pre-erection scheduling given erection date. And then, considering the manpower resource determined by pre-erection scheduling, we also propose manpower resource leveling heuristics in erection scheduling. Various experimental results with real world data show that the proposed heuristics have good performance in terms of scheduling quality and time.

• IEMEK Journal of Embedded Systems and Applications
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• v.12 no.6
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• pp.369-375
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• 2017

In this paper, we present a self-adaptive software platform that enables an IoT gateway to perform autonomous operation considering IoT devices connected each other in resource-constrained environments. Based on the oneM2M device software platform publicly available, we have designed an additional part, called SAS (self-adaptive software) consisting of MAM (memory-aware module), NAM (network-aware module), BAM (battery-aware module), DAM (data-aware module), and DH (decision handler). A prototype system is implemented to show the feasibility of the proposed self-adaptive software architecture. Our proposed system demonstrates that it can adaptively adjust the operation of gateway and connected devices to their resource conditions under the desired service scenarios.