• Steel and Composite Structures
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• 제51권1호
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• pp.25-41
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• 2024

The measurement of pile bearing capacity is crucial for the design of pile foundations, where in-situ tests could be costly and time needed. The primary objective of this research was to investigate the potential use of fuzzy-based techniques to anticipate the maximum weight that concrete driven piles might bear. Despite the existence of several suggested designs, there is a scarcity of specialized studies on the exploration of adaptive neuro-fuzzy inference systems (ANFIS) for the estimation of pile bearing capacity. This paper presents the introduction and validation of a novel technique that integrates the fire hawk optimizer (FHO) and equilibrium optimizer (EO) with the ANFIS, referred to as ANFIS_FHO and ANFIS_EO, respectively. A comprehensive compilation of 472 static load test results for driven piles was located within the database. The recommended framework was built, validated, and tested using the training set (70%), validation set (15%), and testing set (15%) of the dataset, accordingly. Moreover, the sensitivity analysis is performed in order to determine the impact of each input on the output. The results show that ANFIS_FHO and ANFIS_EO both have amazing potential for precisely calculating pile bearing capacity. The R² values obtained for ANFIS_FHO were 0.9817, 0.9753, and 0.9823 for the training, validating, and testing phases. The findings of the examination of uncertainty showed that the ANFIS_FHO system had less uncertainty than the ANFIS_EO model. The research found that the ANFIS_FHO model provides a more satisfactory estimation of the bearing capacity of concrete driven piles when considering various performance evaluations and comparing it with existing literature.

• 한국컴퓨터정보학회논문지
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• 제29권4호
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• pp.47-54
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• 2024

첨단기술을 활용한 문화예술 교육은 기술에 대한 문해력 향상과 자기표현, 그리고 융합적 역량 개발의 측면에서 그 중요성이 증대되고 있다. 이에 혁신적인 멀티모달 AI의 생성과정과 결과평가는 확대된 시청각 경험을 제공하고 창의적 영감을 향상할 수 있다. 특히, AI와 함께 음악을 만드는 과정은 멜로디와 악상을 떠올리는 것부터 가사 개선, 편집과 변주, 악기 연주 등 모든 영역에 걸쳐 혁신적 경험을 제공한다. 이에 본 연구에서는 음악 생성 AI 플랫폼을 활용하여 과제를 수행하고 동료 학습자와 토론하는 과정을 실증적으로 분석하고자 하였다. 그 결과 자발적 참여를 통해 12개의 서비스와 10개의 평가기준 유형을 수집하여 사용패턴과 목적으로 구분할 수 있었다. 이를 토대로 학습자 관점의 AI 기반 교양교육을 위한 학술적, 기술적, 정책적 시사점을 제시하였다.

• Smart Structures and Systems
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• 제20권1호
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• pp.61-74
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• 2017

One of the most reliable and simplest tools for structural vibration control in civil engineering is Tuned Mass Damper, TMD. Provided that the frequency and damping parameters of these dampers are tuned appropriately, they can reduce the vibrations of the structure through their generated inertia forces, as they vibrate continuously. To achieve the optimal parameters of TMD, many different methods have been provided so far. In old approaches, some formulas have been offered based on simplifying models and their applied loadings while novel procedures need to model structures completely in order to obtain TMD parameters. In this paper, with regard to the nonlinear decision-making of fuzzy systems and their enough ability to cope with different unreliability, a method is proposed. Furthermore, by taking advantage of both old and new methods a fuzzy system is designed to be operational and reduce uncertainties related to models and applied loads. To design fuzzy system, it is required to gain data on structures and optimum parameters of TMDs corresponding to these structures. This information is obtained through modeling MDOF systems with various numbers of stories subjected to far and near field earthquakes. The design of the fuzzy systems is performed by three methods: look-up table, the data space grid-partitioning, and clustering. After that, rule weights of Mamdani fuzzy system using the look-up table are optimized through genetic algorithm and rule weights of Sugeno fuzzy system designed based on grid-partitioning methods and clustering data are optimized through ANFIS (Adaptive Neuro-Fuzzy Inference System). By comparing these methods, it is observed that the fuzzy system technique based on data clustering has an efficient function to predict the optimal parameters of TMDs. In this method, average of errors in estimating frequency and damping ratio is close to zero. Also, standard deviation of frequency errors and damping ratio errors decrease by 78% and 4.1% respectively in comparison with the look-up table method. While, this reductions compared to the grid partitioning method are 2.2% and 1.8% respectively. In this research, TMD parameters are estimated for a 15-degree of freedom structure based on designed fuzzy system and are compared to parameters obtained from the genetic algorithm and empirical relations. The progress up to 1.9% and 2% under far-field earthquakes and 0.4% and 2.2% under near-field earthquakes is obtained in decreasing respectively roof maximum displacement and its RMS ratio through fuzzy system method compared to those obtained by empirical relations.

• 감성과학
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• 제23권1호
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• pp.89-102
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• 2020

본 연구는 정서조절 설문지와 정서조절 과제를 사용하여, 정서조절 전략인 재해석과 억제에 대한 경향성과 사용이 일치하는지 탐구하였다. 또한, 성격특성, 회복탄력성 척도를 사용하여 정서조절의 효과성과 관련이 있는 개인 내 변인들을 탐색하였다. 연구 대상은 60명의 여자 대학생으로, 연구 1에서는 40명을 집단 간 설계로 재해석과 억제 집단에 각각 20명씩 무작위로 할당하였고, 연구 2에서는 실험 1에 참가하지 않은 여자 대학생 20명을 대상으로 집단 내 설계로 재해석과 억제 과제를 실시하였다. 연구 결과, 정서조절 과제를 통한 재해석 전략과 억제 전략의 사용은 부정적인 정서를 효과적으로 감소시킨 것으로 나타났다. 둘째, 과제를 통해 측정된 정서조절의 사용과 자가보고 설문지를 통해 측정된 정서조절 경향성은 일치하지 않았다. 셋째, 억제 전략의 사용은 성격 특성의 외향성과 연관되는 것으로 나타났다. 본 연구의 결과는 실제 사용하는 전략과 정서조절 전략에 대한 주관적 평가가 일치하지 않을 수 있음을 시사한다. 또한, 본 연구 결과는 억제에 비해 재해석이 기능적이라고 주장하는 기존의 연구 결과를 지지한다.

• 성인간호학회지
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• 제13권1호
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• pp.15-28
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• 2001

The purpose of this study was to identify the trends of resourcefulness researche studies for suggesting the future direction of study. Study design, types of subjects, measurement tools, study concept, and outcome were examined by reviewing 61 research studies published from 1980 to 1999. The results were as follows: 1. There were 24 works in the 1980s and 37 works in 1990, according to the published year of resourcefulness study. Nonexperimental studies like descriptive study, correlational study and comparative study were more frequent than experimental studies. 2. Research studies that consisted of 30- 100 subjects were the most numerous with 27 studies in all. The majority of study subjects was shown as healthy students and depressive patients. 3. Most studies used Rosenbaum's Self Control Schedule(SCS) for assessing resourcefulness. Reliabilities of resourcefulness researches were cronbach ${\alpha}=.70$ or more. According to statisitical tests done for internal validity, SCS was negatively correlated to maladaptation. Factor analysis revealed that the most parsimonious structure was 3 to 6 factors. The total communality variance in the SCS was about 40 %. Other tools used with the SCS were about coping, depression, satisfaction of life and symptoms, self management and health promotion. 4. In correlational studies, concepts like depression, anxiety, and psychological symptoms were related to resourcefulness negatively. Adaptive functioning, life satisfaction and self achievement had positive correlations to resourcefulness. 5. Studies on comparison between a healthy person and depressive patient or smoker and non-smoker were done. There were coping, depression, symptom, self efficacy, health problem and self-control as comparative concepts. 6. Study subjects consisted of depressive patients in 9 of 18 experimental studies. The majority of studies were done with cognitive-behavioral therapy as an experimental intervention. The most effective treatment was revealed in high resourcefulness group. Since the above findings, resourcefulness research increased since 1980 and mostly non-experimental design for quantitative study were done. In the field of nursing, research about resourcefulness was in an initial stage. It is expected that further research needed to be done. Recommendations on the basis of the present research suggest that it is necessary to replicate studies, develop nursing intervention enhancing resourcefulness and apply it to patients with chronic diseases including cancer.

• 재활간호학회지
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• 제2권1호
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• pp.95-108
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• 1999

The purpose of this study was to identify the effect of the humor intervention program, administred to the hemodialysis patient as an adaptive coping mechanism. The research design was non-equivalent control group non-synchronized design. The study method had been done by investigating the experimental group and control group through the questionnaire on 36 patients who had been out patient hemodialysis room at B hospital in Pusan from August 18 to September 15, 1998. The humor intervention program consisted of 1 TV comedy, 1 home video and 1 comedy film. The humor intervention program was provided to the experimental group for 20-30 minute 3 times every other day at hemodialysis room. Dependent variables were measured by Spielberger's State Anxiety Inventory, Zung's Self Rating Depression Scale, Lefcourt & s Humor Coping Scale. The analysis of the collected data had been done for the hemogeneity test in which general characteristics of the experimental group and the control group had been tested by $X^2$-test and the hemogeneity test had been tested by t-test before using the humor intervention program which is for anxiety, depression and coping of humor. To test the hypothesis the t-test had been given for the difference of anxiety, depression and coping of humor between the two groups. The result were summarized as follows : 1. Anxiety score in the experimental group and control group was not significant difference. 2. Depression score in the experimental group and control group was not significant difference. 3. Coping of humor score in the experimental group and control group was not significant difference. In conclusion, even though humor intervention program did not have any efficient effect on hemodialysis patients in reacting to anxiety, depression and coping humor, it caused very positive reactions from patients, and it also reducted anxiety of patients among the experimental group a little bit. If this program could be sufficiently applied ac cording to the character of every patients with a little bit different appliences such as selection of humor intervention program, frequency and period, it will be used as an efficient the humor intervention program.

• 한국광학회지
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• 제24권5호
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• pp.231-236
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• 2013

본 논문에서는 멀티 어레이 엘이디를 이용한 불연속적인 광원의 빔 패턴이 광학계만으로 연속적인 매트릭스 빔으로 형성되어 광원의 점 소등만으로 다양한 빔 패턴을 구현할 수 있는 지능형 전조등의 광학 설계를 연구하였다. 기존 지능형 전조등의 기술과 다르게 멀티 어레이 엘이디를 이용한 지능형 전조등은 다수의 광원 엘이디와 하나의 광학계 어셈블리 모듈 구성으로 전자 제어를 통해 별도의 기구적인 작동 없이 빔 패턴을 변화시킬 수 있다. 본 연구에서 광학 설계는 상향등과 자동 조정 주행등의 패턴 구현과 광도 값을 만족시키기 위해 LED 앞 단에 2차렌즈 설계와 측벽 설계, 투사렌즈 설계를 실시하였다. 그 결과 불연속적인 광원의 패턴이 광학계를 통해 전방 25 m에서 14개의 동일한 사이즈와 밝기를 갖는 셀들이 모여 연속적인 하나의 매트릭스 빔 패턴을 형성하는 설계 조건을 만족하였다. 또한 설계된 광학계의 제작 및 측정을 통해 상향등의 원거리 시인성을 위한 최대 45000 cd 이상의 배광 법규 조건을 약 50000 cd로 만족하였고, 자동 조정 주행 빔 패턴 구현 시 광원의 소등 영역이 0.32 lx로 측정되어 배광 법규 0.4 lx 이하를 만족하였다.

• 한국정보통신학회논문지
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• 제18권9호
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• pp.2109-2116
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• 2014

본 논문은 무선랜 시스템에서 성능 향상을 위해, 안테나 빔을 전 방향으로 방사하는 기존의 방법과는 달리, 접속한 단말이 존재하는 방향으로만 안테나 빔을 방사하는 빔포밍 시스템을 설계 및 구현하였다. 해당 시스템은 패치형 배열 안테나를 통해 통신을 하며, DSP(Digital Signal Processor)에서 패킷 타입과 단말의 정보를 퀄컴사의 상용 칩으로부터 제공받아 FPGA(Field Programmable Gate Array)로 전송하는 방식으로 동작한다. DSP와 FPGA의 통신 방식은 데이터 송수신시 생기는 지연을 최소화하기 위해 PCI express(Peripheral Component Interconnect express)를 사용하였다. 단말 고유의 MAC(Media Access Control) 주소를 FPGA에서 저장하고 데이터베이스화함으로써 단말들의 위치를 관리할 수 있도록 하였다. 따라서 해당하는 단말로 패킷을 전송할 때, 추정한 위치로 빔을 방사하여 T/P(throughput)를 높일 수 있다. 단말의 위치는 패치형 배열 안테나를 통해 수신한 단말의 SINR(Signal to Interface plus Noise Ratio)을 프리앰블 구간에서 극대화하는 알고리즘을 사용하여 추정하였다. 제안하는 빔포밍 시스템을 Verilog HDL(Hardware Description Language)을 이용하여 FPGA와 퀄컴사의 상용 칩과 연동하여 구현하였으며 실제 운용 환경에서 시험을 통해 구현된 장비가 일반 AP(Access Point) 보다 더 높은 성능을 보이며 통신하는 것을 확인하였다.

• 한국정밀공학회지
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• 제30권1호
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• pp.11-17
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• 2013

'Multi-scale mass-deployable cooperative robots' is a next generation robotics paradigm where a large number of robots that vary in size cooperate in a hierarchical fashion to collect information in various environments. While this paradigm can exhibit the effective solution for exploration of the wide area consisting of various types of terrain, its technical maturity is still in its infant state and many technical hurdles should be resolved to realize this paradigm. In this paper, we propose to develop new design and manufacturing methodologies for the multi-scale mass-deployable cooperative robots. In doing so, we present various fundamental technologies in four different research fields. (1) Adaptable design methods consist of compliant mechanisms and hierarchical structures which provide robots with a unified way to overcome various and irregular terrains. (2) Soft composite materials realize the compliancy in these structures. (3) Multi-scale integrative manufacturing techniques are convergence of traditional methods for producing various sized robots assembled by such materials. Finally, (4) the control and communication techniques for the massive swarm robot systems enable multiple functionally simple robots to accomplish the complex job by effective job distribution.

• 한국항행학회논문지
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• 제25권5호
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• pp.426-432
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• 2021

CW (continuous wave) 도플러 레이다는 카메라와 달리 사생활 침해 문제를 해결할 수 있고, 비접촉 방식으로 신호를 얻을 수 있다는 장점이 있다. 따라서, 본 논문에서는 CW 도플러 레이다를 이용한 사람 행동 인식 시스템을 제안하고, 가속을 위한 하드웨어 설계 및 구현 결과를 제시한다. CW 도플러 레이다는 사람의 연속된 동작에 대한 신호를 측정한다. 이에, 동작 분류를 위한 단일 스펙트로그램을 얻기 위해 운동 동작의 횟수를 세는 기법을 제안하였다. 또한, 연산의 복잡도와 메모리 사용량을 최소화하기 위해 동작 분류에 BNN (binarized neural network)을 사용하였고, 검증 결과 94%의 정확도를 보임을 확인하였다. BNN의 복잡한 연산을 가속하기 위해 FPGA를 이용하여 BNN 가속기가 설계 및 구현되었다. 제안된 사람 행동 인식 시스템은 logic 7,673개, register 12,105개, combinational ALUT (adaptive look up table) 10,211개, block memory 18.7 Kb를 사용하여 구현되었으며, 성능 평가 결과 소프트웨어 구현 대비 연산 속도가 99.97% 향상되었다.