• Journal of the Economic Geographical Society of Korea
• /
• v.20 no.2
• /
• pp.189-213
• /
• 2017

This study seeks to critically examine the significance and limits of the cluster adaptive cycle model for analysis of cluster evolution and to propose research issues for future analysis of cluster evolution based on this critical examination. Until the 1980s, research on industrial complexes including clusters was based on a 'static perspective' that focuses on the aspect of economic space at a specific point in time, but the research paradigm has recently shifted to a 'dynamic perspective' focusing on 'evolution' of 'complex adaptive systems'. As a result, the adaptive cycle model has attracted attention as an analysis tool of dynamically evolving clusters. However, the cluster adaptive cycle model has emerged by being appropriately modified and expanded according to the properties of the cluster and its evolution. The cluster adaptive cycle model is a comprehensive analysis framework that identifies the characteristics of cluster evolution in terms of resource accumulation, interdependence, and resilience and classifies cluster evolution paths into six different categories. Nevertheless, there is still a need for further discussion and supplementation in terms of theoretical and empirical research to expand and deepen the model. Therefore, research issues for future analysis of cluster evolution are to specify and elaborate the cluster evolution model, to emphasize the concept of resilience, and to verify the applicability and usefulness of the model through empirical research.

• Research in Mathematical Education
• /
• v.26 no.3
• /
• pp.167-202
• /
• 2023

A central problem of mathematics teaching worldwide is probably the insufficient adaptive handling of tasks-especially in computational practice phases and modeling tasks. All students in a classroom must often work on the same tasks. In the process, the high-achieving students are often underchallenged, and the low-achieving ones are overchallenged. This publication uses different modeling of the tennis serve as an example to show a possible solution to the problem and develops and discusses one adaptive task each for middle school, high school, and college using three mathematical models of the tennis serve each time. From model to model within the task, the complexity of the modeling increases, the mathematical or physical demands on the students increase, and the new modeling leads to more realistic results. The proposed models offer the possibility to address heterogeneous learning groups by their arrangement in the surface structure of the so-called parallel adaptive task and to stimulate adaptive mathematics teaching on the instructional topic of mathematical modeling. Models A through C are suitable for middle school instruction, models C through E for high school, and models E through G for college. The models are classified in the specific modeling cycle and its extension by a digital tool model, and individual modeling steps are explained. The advantages of the presented models regarding teaching and learning mathematical modeling are elaborated. In addition, we report our first teaching experiences with the developed parallel adaptive tasks.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.8
• /
• pp.725-734
• /
• 2011

At high angles of attack, aircraft dynamics can display an oscillatory lateral behavior that manifests itself as a limit cycle known as wing rock. In this paper, a classical and neural network based adaptive control design methods of adaptively stabilizing the oscillatory motion by adapting uncertainties are described in detail. All methods are simulated and compared using a model for an 80o swept delta wing.

• Journal of Information Processing Systems
• /
• v.14 no.4
• /
• pp.948-960
• /
• 2018

Many mobile sensing frameworks have been developed to help researcher doing their mobile sensing research. However, energy consumption is still an issue in the mobile sensing research, and the existing frameworks do not provide enough solution for solving the issue. We have surveyed several mobile sensing frameworks and carefully chose one framework to improve. We have designed an adaptive sampling module for a mobile sensing framework to help solve the energy consumption issue. However, in this study, we limit our design to an adaptive sampling module for the location and motion sensors. In our adaptive sampling module, we utilize the significant motion sensor to help the adaptive sampling. We experimented with two sampling strategies that utilized the significant motion sensor to achieve low-power consumption during the continuous sampling. The first strategy is to utilize the sensor naively only while the second one is to add the duty cycle to the naive approach. We show that both strategies achieve low energy consumption, but the one that is combined with the duty cycle achieves better result.

• Proceedings of the IEEK Conference
• /
• 2005.11a
• /
• pp.687-690
• /
• 2005

H.264/AVC에서 압축 효율을 향상시키기 위해 사용된 entropy coding중에 CABAC(Context-based Adaptive Binary Arithmetic Coding)은 하드웨어 복잡도가 높고 bit-serial 과정에서 data dependancy가 존재하기 때문에 빠른 연산이 어렵다. 본 논문에서는 adaptive arithmetic encoder와 정규화 과정을 효율적으로 구성하여 각 입력 심벌이 정규화 과정의 반복횟수에 관계없이 고정된 cycle에 encoding이 되도록 하였다. 제안한 구조는 pipeline으로 구성하기 용이하며, 이 경우 매 cycle에 한 입력 심벌의 encoding이 가능하다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.10
• /
• pp.4754-4773
• /
• 2018

In sensor medium access control (SMAC) protocol, sensor nodes can only access the channel in the scheduling and listening period. However, this fixed working method may generate data latency and high conflict. To solve those problems, scheduling duty in the original SMAC protocol is divided into multiple small scheduling duties (micro duty MD). By applying different micro-dispersed contention channel, sensor nodes can reduce the collision probability of the data and thereby save energy. Based on the given micro-duty, this paper presents an adaptive duty cycle (DC) and back-off algorithm, aiming at detecting the fixed duty cycle in SMAC protocol. According to the given buffer queue length, sensor nodes dynamically change the duty cycle. In the context of low duty cycle and low flow, fair binary exponential back-off (F-BEB) algorithm is applied to reduce data latency. In the context of high duty cycle and high flow, capture avoidance binary exponential back-off (CA-BEB) algorithm is used to further reduce the conflict probability for saving energy consumption. Based on the above two contexts, we propose an improved SMAC protocol, micro duty adaptive SMAC protocol (MDA-SMAC). Comparing the performance between MDA-SMAC protocol and SMAC protocol on the NS-2 simulation platform, the results show that, MDA-SMAC protocol performs better in terms of energy consumption, latency and effective throughput than SMAC protocol, especially in the condition of more crowded network traffic and more sensor nodes.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.42 no.12
• /
• pp.37-44
• /
• 2005

This paper proposes a hybrid scheme for dynamic bandwidth allocation(DBA) in Ethernet passive optical network(EPON), which combines advantages of adaptive cycle and constant cycle-based schemes. The proposed scheme is based on IPACT scheme, but it operates as adaptive cycle or constant cycle mode according to the queue status of optical line terminal(OLT) for downstream transmission. Simulation results showed that the proposed scheme could achieve a similar throughput in downstream transmission to a constant cycle-based DBA scheme, while producing a similar delay performance to the IPACT scheme in upstream transmission.

• The Journal of Natural Sciences
• /
• v.9 no.1
• /
• pp.45-52
• /
• 1997

We have examined the effects of low concentrations of MNNG, alkylating agent, in survival and mutagenesis in Aspergillus nidulans. Pretreatments of cells with nontoxic and submutagenic doses of MNNG did not reduce the cytotoxic and mutagenic effects of exposure to a high concentration of drug. The results imply that adaptive responses on survival and mutagenesis for MNNG treatments do not occur in Aspergillus nidulans. In the first mitotic cell cycle during germination, the sensitivity to MNNG has been investigated at hourly time interval, and compared with that for UV irradiation. In both UV and MNNG treatments, the sensitivity increased till S cell stage, and decreased while DNA replication continued. Different from that show for UV irradiation, lethality to MNNG reached to the maximum at G2 cell stage.

• Journal of the Korean Regional Science Association
• /
• v.40 no.3
• /
• pp.109-126
• /
• 2024

The central government has been promoting innovation cities since the early 2000s for the balanced development of the country in order to solve the problems of overcrowding in the metropolitan area and underdevelopment of the country due to rapid urbanization since the 1980s. The 10 innovation cities built through the regional relocation of public institutions were expected to have positive effects such as economic revitalization and population influx, but uncertainties and various externalities still exist. Therefore, this study aims to analyze innovation cities from the perspective of urban resilience to create sustainable cities. To this end, the research analyzed urban factors in the physical, natural, social, economic, and institutional dimensions of Ulsan Ujeong Innovation City, and applied the Adaptive Cycle and Panarchy to comprehensively analyze them. As a result of the analysis, it was found that the built, socio-economic, and natural environments are currently undergoing the adaptive cycle stages of preservation, reorganization, and growth, respectively, and the interaction and structural causal relationships between Korea, Ulsan Metropolitan City, and Ulsan Ujeong Innovation City were identified. The study concluded that Ulsan Ujeong Innovation City can be sustainable by utilizing opportunities such as the central government's Innovation City Season 2 and financial support, construction of Janghyeon Advanced Industrial Complex, and fostering local innovation clusters according to local conditions.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.10 no.1
• /
• pp.103-110
• /
• 2015

WBAN(Wireless Body Area Network) is a Wireless Sensor Network for supporting various applications around body within 2~3m which consists of medical and non-medical device. MAC in WBAN environment should satisfy requirements such as low power consumption, various transmission rate, QoS, and duty-cycle, efficiently distribute frequency band, be strong at traffic load and save energy. This paper proposes AQ(Adaptive Queuing) MAC superframe structure for efficient energy use, considering the increase of traffic load. The simulation result also show that transmission rate and average MAC delay rate is improved comparing IEEE 802.15.4 MAC with AQ MAC.