• Computers and Concrete
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• 제16권4호
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• pp.503-529
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• 2015

Traditionally, multi-story buildings are designed to provide stiffer structural support to withstand lateral earthquake loading. Introducing flexible elements at the base of a structure and providing sufficient damping is an alternative way to mitigate seismic hazards. These features can be achieved with a device known as an isolator. This paper covers the design of base isolators for multi-story buildings in medium-risk seismicity regions and evaluates the structural responses of such isolators. The well-known tower building for police personnel built in Dhaka, Bangladesh by the Public Works Department (PWD) has been used as a case study to justify the viability of incorporating base isolators. The objective of this research was to establish a simplified model of the building that can be effectively used for dynamic analysis, to evaluate the structural status, and to suggest an alternative option to handle the lateral seismic load. A finite element model was incorporated to understand the structural responses. Rubber-steel bearing (RSB) isolators such as Lead rubber bearing (LRB) and high damping rubber bearing (HDRB) were used in the model to insert an isolator link element in the structural base. The nonlinearities of rubber-steel bearings were considered in detail. Linear static, linear dynamic, and nonlinear dynamic analyses were performed for both fixed-based (FB) and base isolated (BI) buildings considering the earthquake accelerograms, histories, and response spectra of the geological sites. Both the time-domain and frequency-domain approaches were used for dynamic solutions. The results indicated that for existing multi-story buildings, RSB diminishes the muscular amount of structural response compared to conventional non-isolated structures. The device also allows for higher horizontal displacement and greater structural flexibility. The suggested isolation technique is able to mitigate the structural hazard under even strong earthquake vulnerability.

• Journal of Korean Academy of Oral Health
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• 제41권1호
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• pp.16-21
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• 2017

Objectives: Dental caries and periodontitis are major oral bacterial infections associated with dental plaque. Infection and inflammation play a role in carcinogenesis, and a significant link has been found between some highly prevalent oral and dental diseases and some types of cancer. Therefore, the aim of this study was to evaluate the relationship between cancer and oral health among Korean adults. Methods: Data from the 6th Korea National Health and Nutrition Examination Survey were used to analyze the incidence of cancer according to oral health. Demographic and socioeconomic statuses and oral behavior of the participants was analyzed using complex chi-square tests. Logistic regression was used to analyze the relationship between a high DMFT index and cancer by calculating the 95% confidence intervals. Results: In total, 6,450 case-control subjects were included. Significant difference was observed in the DMFT index, but not in periodontal diseases, between the cases and controls. The odds ratio for cancer was 1.80 (95% confidence interval: 1.18 to 2.73) in the high-risk group. However, no significant difference was observed after adjusting for age, education level, and income. Conclusions: The results provide potential evidence of a significant association between cancer and oral disease.

• 정보보호학회논문지
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• 제16권4호
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• pp.43-57
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• 2006

소프트웨어 컴포넌트를 이용하여 시스템을 구성하는 경우 그리 간단하지 않은데, 그것은 링크 과정 자체가 서로 다른 버전들과 디지털 서명, 정적인 타입 정보나 네트워크로 전송된 소프트웨어, 그리고 서로 다른 판매자에 의한 컴포넌트들을 모두 포함하는 복잡한 과정이기 때문이다. 만약 링크과정에 적용될 수 있는 링크 정책을 수립하고 이를 링크 시에 적용할 수 있는 방법이 있다면 이러한 복잡함을 해결하는 좋은 수단이 된다. 시큐어 링킹(Secure Linking)은 사용자가 안전한 링크를 위한 정책을 만들고 이를 링크 시에 적용할 수 있도록 해주는 새로운 링크 프로토콜이며, 시큐어 링크 프레임워크(Secure Linking Framework)는 시큐어 링크 시스템 구현을 위한 논리적 프레임워크이다. 본 논문에서는 시큐어 링크 프레임워크를 이용하여 마이크로 소프트의 닷넷(.NET)에서 사용되는 어셈블리의 링크 과정을 설명함으로써 시큐어 링킹이 실제로 사용되는 링크 시스템을 나타낼 수 있을 만큼 풍부한 표현력과 실용성을 가지고 있음을 증명한다. 또한 이 과정에서 나타난 어셈블리 코드 서명의 문제점에 대한 논의를 통해서 논리에 기반을 둔 링크 프레임워크가 가지는 장점을 보이고자 한다.

• 한국전자통신학회논문지
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• 제16권6호
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• pp.1223-1230
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• 2021

최근 에너지 자원관리는 전 세계적인 주요 관심사이다. 에너지원 생산의 한계 조건 속에서, 효과적인 에너지 관리 활동은 에너지 수요 및 생산을 최소화하고 이는 환경이 미치는 영향을 최소화할 수 있다. 본 논문은 주거형 건물에서 에너지 소비자에게 전기 사용에 대한 실시간 정보를 제공할 수 있는 가정용 전기에너지 모니터링 시스템의 프로토타입 설계를 제안하고자 한다. 제안된 시스템은 자체 개발된 센싱 시스템, 데이터처리시스템, 원격 모니터링 서버 시스템으로 구성된다. 주거형 건물내에 설치 적용된 센싱 시스템은 전원 공급을 제어하는 릴레이, 부하 전기기기의 전류를 감지하는 CT센서, Kmote로 구성된 무선 스마트 플러그로 구성된다. 공동/단독 주거형 건물에서 3개월 동안의 가전제품별 에너지 소비량 데이터를 분석하여 제시하였으며, 실험결과는 에너지 소비 패턴과 현황을 추정할 수 있는 가능성을 확인하여 제시하고 있다.

• 한국전자통신학회논문지
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• 제16권6호
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• pp.1153-1160
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• 2021

본 논문은 소프트웨어 정의 네트워크에서 심층강화학습을 활용하여 최적의 경로를 결정하는 라우팅 알고리즘을 제안한다. 학습을 위한 심층강화학습 모델은 DQN 을 기반으로 하고, 입력은 현재 네트워크 상태, 발신지, 목적지 노드이고, 출력은 발신지에서 목적지까지의 경로 리스트를 반환한다. 라우팅 작업을 이산 제어 문제로 정의하며, 라우팅을 위한 서비스 품질 파라미터는 지연, 대역폭, 손실률을 고려하였다. 라우팅 에이전트는 사용자의 서비스 품질 프로파일에 따라 적절한 서비스 등급으로 분류하고, SDN에서 수집된 현재 네트워크 상태로부터 각 링크 별로 제공할 수 있는 서비스 등급을 변환한다. 이러한 변환된 정보를 토대로 발신지에서부터 목적지까지 요구되는 서비스 등급을 만족시키는 경로를 선택하도록 학습을 한다. 시뮬레이션 결과는 제안한 알고리즘이 일정한 에피소드를 진행하게 되면 올바른 경로를 선택하게 되고, 학습이 성공적으로 수행됨을 나타냈다.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.776-782
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• 2022

Corn-soybean meal diets are commonly used in the pork industry as a primary source of energy and protein. However, such a diet generally contains non-starch polysaccharides (NSPs) which present a challenge in finding ways to improve their availability and digestibility. Dietary multi-carbohydrases (MCs) have been proposed as an efficient approach to utilize NSPs, and can result in improved growth performance and host intestinal fitness. In this study, we evaluated the effects of MC in lactation diets on gut microbiota composition of lactating sows and their litters. The experimental design contained two dietary treatments, a diet based on corn-soybean meal (CON), and CON supplemented with 0.01% multigrain carbohydrases (MCs). Sow and piglet fecal samples were collected on days 7 and 28 after farrowing. Based on the results from 16S rRNA gene amplicon sequencing, MC led to changes in species diversity and altered the microbial compositions in lactating sows and their piglets. Specifically, the MC treatment induced an increase in the proportions of Lactobacillus in piglets. Clostridium and Spirochaetaceae showed a significantly reduced proportion in MC-treated sows at day 28. Our results support the beneficial effects of dietary carbohydrases and their link with improved production due to better host fitness outcomes and gut microbiota composition.

• 한국항행학회논문지
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• 제26권5호
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• pp.272-280
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• 2022

항공모함은 해상에서 항공기지 역할을 하는 전투함으로 항공기를 운용하는 군용함정으로 탑재된 항공기를 통하여 전투를 수행한다. 해군은 2033년경 수직이착륙 전투기와 헬기를 탑재할 수 있는 4만 톤급의 경항공모함 운용계획을 제시하였는데 본 연구는 이러한점에 착안하여 해외사례를 기초로 우리나라에서 경항공모함을 운영에서 요구되는 항공지원시스템 가운데 항공관제장비의 운영에 대해 고찰하였다. 필수장비로 공역 관제를 위한 PriFly, TWR의 ILARTS, ILM와 접근관제를 위한 ASR, PAR, LAAS 또는 RNAV, PALS(JPALS) 이 필요하며, 항행안전시설을 위한 URN-25 TACAN, ICLS(El/Az), ACLS OLS, MOVLAS, IFLOLS 등과 함께 통신네트워크를 위한 LINK-16 및 CEC, SATCOM이 요구되며, 적아 식별장비의 구축이 요구된다. 본 연구는 2부로 구성되며 2부에서는 구체적인 항공모함에서의 관제 방법을 기술할 것이다.

• 환경생물
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• 제40권2호
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• pp.206-213
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• 2022

고리매는 동해안에서 식용되어온 유용 갈조류이며, 다양한 생리활성물질을 함유하여 이용이 기대되는 해조류이다. 이 연구는 2021년 1월부터 12월까지 강원도 주문진읍 소돌해안에서 고리매 개체군의 생장 및 성숙 패턴을 밝히기 위하여 수행되었다. 고리매 개체군의 정량조사를 위해 월별 형태분석, 밀도 및 현존량 분석을 실시하였다. 조사지역에서 고리매의 최대엽장은 3월(수온 10.6℃)에 16.3±3.0 cm, 평균 밀도는 32.5±2.9 ind. m^-2 및 평균 현존량은 96.0±12.1 g fresh-wt. m^-2 였다. 고리매 엽체의 성숙은 4월(수온 12.1℃)에 최성기를 보였으며, 성숙에 요구되는 성숙유효적산온도는 162.5 degree-days였다.

• Advances in concrete construction
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• 제16권1호
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• pp.69-78
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• 2023

This investigation delves into the adverse repercussions stemming from the impact of arsenic on steel pipes concealed within soil designated for rice cultivation. Simultaneously, the study aims to ascertain effective techniques for detecting arsenic in the soil and to provide strategies for mitigating the corrosion of steel pipes. The realm of nanotechnology presents promising avenues for addressing the intricate intersection of renewable energy, oil, and environmental pollution from a novel perspective. Nanostructured materials, characterized by distinct chemical and physical attributes, unveil novel pathways for pioneering materials that exert a substantial impact across diverse realms of food production, storage, packaging, and quality control. Within the scope of the food industry, the scope of nanotechnology encompasses processes, storage methodologies, packaging paradigms, and safeguards to ensure the safety of consumables. Of particular note, silver nanoparticles, in addition to their commendable antibacterial efficacy, boast anti-fungal and anti-inflammatory prowess, environmental compatibility, minimal irritability and allergenicity, resilience to microbial antagonism, thermal stability, and robustness. Confronting the pressing issue of arsenic contamination within both environmental settings and the food supply is of paramount importance to preserve public health and ecological equilibrium. In response, this study introduces detection kits predicated upon silver nanoparticles, providing an expeditious and economically feasible avenue for identifying arsenic concentrations ranging from 0.5 to 3 ppm within rice. Subsequent quantification employs Hydride Atomic Absorption Spectroscopy (HG-AAS), which features a detection threshold of 0.05 ㎍/l. A salient advantage inherent in the HG-AAS methodology lies in its capacity to segregate analytes from the sample matrix, thereby significantly reducing instances of spectral interference. Importantly, the presence of arsenic in the soil beneath rice cultivation establishes a causative link to steel pipe corrosion, with potential consequences extending to food contamination-an intricate facet embedded within the broader tapestry of renewable energy, oil, and environmental pollution.

• The Journal of Advanced Prosthodontics
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• 제16권2호
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• pp.105-114
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• 2024

PURPOSE. This study aimed to evaluate the effect of pretreatment of three different universal adhesives (Single Bond Universal [SBU], All-Bond Universal [ABU], and Prime&Bond universal [PBU]) on the bonding durability of an adhesive (Panavia F 2.0, PF) and a conventional (Duo-Link, DL) resin cements to air-abraded zirconia. MATERIALS AND METHODS. Rectangular-shaped zirconia specimens were prepared. The chemical composition and surface energy parameters of the materials were studied by Fourier transform infrared spectroscopy and contact angle measurement, respectively. To evaluate resin bonding to the zirconia, all the bonding specimens were immersed in water for 24 h and the specimens to be aged were additionally thermocycled 10000 times before the shear bond strength (SBS) test. RESULTS. The materials showed different surface energy parameters, including the degree of hydrophilicity/hydrophobicity. While the DL/CON (no pretreatment) showed the lowest SBS and a significant decrease in the value after thermocycling (P < .001), the PF/CON obtained a higher SBS value than the DL/CON (P < .001) and no decrease even after thermocycling (P = .839). When the universal adhesives were used with DL, their SBS values were higher than the CON (P < .05), but the trend was adhesive-specific. In conjunction with PF, the PF/SBU produced the highest SBS followed by the PF/ABU (P = .002), showing no significant decrease after thermocycling (P > .05). The initial SBS of the PF/PBU was similar to the PF/CON (P = .999), but the value decreased after thermocycling (P < .001). CONCLUSION. The universal adhesive pretreatment did not necessarily show a synergistic effect on the bonding performance of an adhesive resin cement, whereas the pretreatment was beneficial to bond strength and durability of a conventional resin cement.