• Kyungpook Mathematical Journal
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• v.56 no.1
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• pp.83-94
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• 2016

Let M and N be modules over a ring R. The purpose of this paper is to study modules M, N for which the bi-module [M, N] is regular or pi. It is proved that the bi-module [M, N] is regular if and only if a module N is semi M-projective and $Im({\alpha}){\subseteq}^{\oplus}N$ for all ${\alpha}{\in}[M,N]$, if and only if a module M is semi N-injective and $Ker({\alpha}){\subseteq}^{\oplus}N$ for all ${\alpha}{\in}[M,N]$. Also, it is proved that the bi-module [M, N] is pi if and only if a module N is direct M-projective and for any ${\alpha}{\in}[M,N]$ there exists ${\beta}{\in}[M,N]$ such that $Im({\alpha}{\beta}){\subseteq}^{\oplus}N$, if and only if a module M is direct N-injective and for any ${\alpha}{\in}[M,N]$ there exists ${\beta}{\in}[M,N]$ such that $Ker({\beta}{\alpha}){\subseteq}^{\oplus}M$. The relationship between the Jacobson radical and the (co)singular ideal of [M, N] is described.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.3
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• pp.113-121
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• 2021

In this study, the thermal characteristics of cold and hot water mattress units equipped with thermoelectric modules were investigated via numerical analyses. Cold and hot water mattress products that are currently in existence use manual methods requiring refrigerants to be added to the hot water boiler. However, the cold and hot water mattress units using thermoelectric modules can provide improved efficiency via energy savings and actively resolving environmental pollution problems. To determine the efficiency of the thermoelectric module, the mattress was modeled and its efficiency was analyzed for the cooling and heating processes using two 100-W-class and one 200-W-class thermoelectric modules, respectively. From the results of this study, it was confirmed that when two 100-W-class modules were used, the application area was larger than when a single 200-W-class module was used, with uniform temperature distribution and improved performance compared to existing products in terms of electrical energy.

• Bulletin of the Korean Mathematical Society
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• v.59 no.4
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• pp.917-928
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• 2022

Let R be a commutative Noetherian ring and I an ideal of R. In this paper, we study colocalization of generalized local homology modules. We intend to establish a dual case of local-global principle for the finiteness of generalized local cohomology modules. Let M be a finitely generated R-module and N a representable R-module. We introduce the notions of the representation dimension r^I(M, N) and artinianness dimension a^I(M, N) of M, N with respect to I by r^I(M, N) = inf{i ∈ ℕ₀ : H^I_i(M, N) is not representable} and a^I(M, N) = inf{i ∈ ℕ₀ : H^I_i(M, N) is not artinian} and we show that a^I(M, N) = r^I(M, N) = inf{r^IR_𝔭 (M_𝔭,𝔭N) : 𝔭 ∈ Spec(R)} ≥ inf{a^IR_𝔭 (M_𝔭,𝔭N) : 𝔭 ∈ Spec(R)}. Also, in the case where R is semi-local and N a semi discrete linearly compact R-module such that N/∩_t>0I^tN is artinian we prove that inf{i : H^I_i(M, N) is not minimax}=inf{r^IR_𝔭 (M_𝔭,𝔭N) : 𝔭 ∈ Spec(R)＼Max(R)}.

• Honam Mathematical Journal
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• v.18 no.1
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• pp.5-15
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• 1996

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.6 s.97
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• pp.580-585
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• 2005

Two high-efficiency and high power power-combing modules were developed using slotline-to-microstrip transition at V-band. Power-combining modules incorporating two MMIC power amplifiers demonstrated combining efficiencies higher than $80\%$(maximum $86\%$) with saturated output power of 22.96 dBm and 22.81 dBm, respectively. The measurement of back-to-back connected combiners demonstrated insertion loss less than 1.2 dB with return loss better than 15 dB around 60 GHz, respectively.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.431-436
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• 2005

In this paper, we design and implement modules for disk backup using the backup devices in SAN clusters. The proposed backup modules provide device management features that manage a number of backup devices and groups backup devices into logical units called pools in SAN clusters. It also supports pre/post script to process additional actions for users during backup and restore processing, and provides life cycle management for backup data.

• Proceedings of the Korea Information Processing Society Conference
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• 2024.05a
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• pp.235-238
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• 2024

This paper investigates the integration of ARIA cryptography within hardware secure modules to bolster IoT security. We present a comparative analysis of two prominent IoT communication protocols, MQTT and LwM2M, augmented with ARIA cryptography. The study evaluates their performance, security, and scalability in practical IoT applications. Our experimental setup comprises FPGA-enabled hardware secure modules interfaced with Raspberry Pi acting as an MQTT and LwM2M client. We utilize the Mosquitto MQTT server and an LwM2M server deployed on AWS IoT. Through rigorous experimentation, we measure various performance metrics, including latency, throughput, and resource utilization. Additionally, security aspects are scrutinized, assessing the resilience of each protocol against common IoT security threats. Our findings highlight the efficacy of ARIA cryptography in bolstering IoT security and reveal insights into the comparative strengths and weaknesses of MQTT and LwM2M protocols. These results contribute to the development of robust and secure IoT systems, paving the way for future research in this domain.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.478-483
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• 2017

This paper investigated experimentally the performance of cooling systems using thermoelectric and piezoelectric modules for local heating and temperature control, such as a handheld electronic devices. The temperature distribution of the cooling region using thermoelectric modules was measured when the piezoelectric module was and was not with a frequency of 80Hz and 110Hz. The coefficients of performance were also calculated by the temperature results, and the thermo-flow phenomena in the cold region was visualized under the same conditions. The results of the temperature distribution measurements and the coefficient of performance showed that the cooling performance of the cooling system using thermoelectric modules can be improved by operating the piezoelectric module. In addition, when the piezoelectric module was operated based on the result of visualization in the cold region, which was formed by thermoelectric modules, the performance thermoelectric cooling was improved by the thermo-flow formed in the entire cold region as the forced convection of vibration was generated on the local cold region by the piezoelectric module.

• Journal of The Korean Association For Science Education
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• v.24 no.2
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• pp.328-342
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• 2004

This study aims to develop STS modules which consider the local concerns of Korean society and their authentic evaluation instruments. Their titles are as follows: 'Health-Aiding Foods, are they necessary?', 'Competition between Alien and Native Species', 'Living Lesson of Lake Shihwa', and 'Problems of food wastes; Would you like to throw them away, if they are money?' All of them deal with issues unique to Korean local situations. Each module consisted of two versions; a student worksheet and a teachers' guide. Students' activities were categorized into six processes such as group activities, investigation, discussion and presentation, experiments, field trip, and multiple intelligence activities. Various assessment tools and abilities for the decision-making in their STS classes were also included. In order to validate these modules, 24 teachers who have been teaching science, biology and environmental science in the secondary schools reviewed these modules and provided feedbacks about their validity and usefulness. We expect that the various rubrics included in each module will provide teachers creative and flexible assessment methods for students' understandings and their decision-making abilities toward the issues.

• 한국지구과학회:학술대회논문집
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• 2003.09a
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• pp.3-10
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• 2003

Curriculum reform has been a significant emphasis for most of countries all over the world for the past few years. It was the first time for Taiwan to develop a new Science and Life Technology curriculum Standards (SaLTS) for grades 1 through 9 compulsory educations. The SaLTS features integrated science content with the aim at motivating students to learn science and encouraging students to apply science to their everyday life, which is practically well aligned with the philosophical essence and foundations of Earth Systems Education (ESE). This paper calls attention to the importance of the inclusion of ESE into the forthcoming science curricula of Taiwan and worldwide and provides some exemplary ESE-inspired curriculum and instructional modules that have been successfully implemented in the secondary schools of Taiwan. Hopefully, this paper can shed some lights on the future development of the ESE-based science curricula, instructional modules, and teacher preparation programs.