• Current Optics and Photonics
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• 제6권5호
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• pp.479-488
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• 2022

To account for the internal thermal effects of solid-state lasers, a method using a back propagation (BP) neural network integrated with a particle swarm optimization (PSO) algorithm is developed, which is a new wavefront distortion correction technique. In particular, by using a slab laser model, a series of fiber pumped sources are employed to form a controlled array to pump the gain medium, allowing the internal temperature field of the gain medium to be designed by altering the power of each pump source. Furthermore, the BP artificial neural network is employed to construct a nonlinear mapping relationship between the power matrix of the pump array and the thermally induced wavefront aberration. Lastly, the suppression of thermally induced wavefront distortion can be achieved by changing the power matrix of the pump array and obtaining the optimal pump light intensity distribution combined using the PSO algorithm. The minimal beam quality β can be obtained by optimally distributing the pumping light. Compared with the method of designing uniform pumping light into the gain medium, the theoretically computed single pass beam quality β value is optimized from 5.34 to 1.28. In this numerical analysis, experiments are conducted to validate the relationship between the thermally generated wavefront and certain pumping light distributions.

• Archives of Plastic Surgery
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• 제48권4호
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• pp.433-439
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• 2021

Acellular dermal matrices (ADM) are a novel graft. The goal of this systematic review is to evaluate the evidence behind differences in human and porcine ADM, irrelevant of manufacturing method, and to determine if there is enough of an evidence base to change clinical practice. An extensive literature search was performed through MEDLINE and Embase with search terms defining a population, intervention and outcome. Title and abstract exclusion were performed with other exclusion criteria. In 191 articles were found after exclusion of duplicates, with only 29 remaining following exclusions. Ten studies were found to have level I and II evidence (I=3, II=8), of which two were histopathological, one was an animal model, one was a systematic review, and six were clinical. The remaining studies were reviewed and considered for discussion, but did not hold high enough standards for medical evidence. Strong clinical evidence already exists for the use of human ADM, but questions of access, cost, and ethics require consideration of a xenograft. Histopathologically, evidence suggests minimal long-term differences between human and porcine ADM, although there is a short acute immune response with porcine ADM. Clinically, there is limited difference in outcomes, with a small range in effect of different ADM preparations. Considering the effectiveness of ADM in wound healing, more high-level research with appropriate statistical analysis to facilitate a future meta-analysis is recommended to justify a transition from human to porcine ADM.

• 대순사상과 동아시아종교
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• 제1권1호
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• pp.17-37
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• 2021

Scholars of new religious movements have emphasized the role of "second founders," such as Judge J.F. Rutherford for the Jehovah's Witnesses, Brigham Young for the Mormons, or Deguchi Onisaburo for Oomoto. They systematize and structure movements often created by the "first founders" with a minimal organization only. The paper argues that the model for the sequence first founder/second founder described by these scholars is the relationship between Jesus and Paul of Tarsus at the origins of Christianity. It proposes a comparison between Jesus of Nazareth and Kang Jeungsan, who established the tradition leading to present-day Daesoon Jinrihoe. It then summarizes the biography of Jo Jeongsan, recognized by Daesoon Jinrihoe as its "second founder" within the same tradition, and discusses the analogies between his connection to the "first founder," Kang Jeungsan, and the connection Paul of Tarsus established with Jesus Christ. The paper considers recent scholarship about Paul, often described as the "New Perspective on Pauline Scholarship." Paul never personally met Jesus Christ, except after the latter's death through a spiritual revelation, just as Jo Jeongsan never met Kang Jeungsan, except after his death, when he manifested himself to him in spirit. Nonetheless, Paul was able to decisively shape the largest branch among the followers of Jesus Christ, just as Jo Jeongsan originated the lineage leading to Daesoon Jinrihoe, currently the largest religious order among those recognizing Kang Jeungsan as the incarnated Supreme God.

• Structural Engineering and Mechanics
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• 제86권6호
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• pp.765-778
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• 2023

This study investigates the free vibration and buckling analyses of isotropic curved plate structures fixed at all ends. The Kirchhoff-Love Plate Theory (KLPT) and Finite Element Method (FEM) are employed to model the curved structure. In order to perform the finite element analysis, a four-node quadrilateral element with 5 degrees of freedom (DOF) at each node is utilized. Additionally, the drilling effect (θ_z) is considered as minimal to satisfy the DOF of the structure. Lagrange's equation of motion is used in order to obtain the first ten natural frequencies and the critical buckling values of the structure. The effects of various radii of curvatures and aspect ratio on the natural frequency and critical buckling load values for the single-bay and two-bay curved frames are investigated within this scope. A computer code based on finite element analysis is developed to perform free vibration and buckling analysis of curved plate frames. The natural frequency and critical buckling load values of the present study are compared with ANSYS R18.2 results. It has been concluded that the results of the present study are in good agreement with ANSYS results for different radii of curvatures and aspect ratio values of both single-bay and two-bay structures.

• Geomechanics and Engineering
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• 제37권4호
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• pp.395-418
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• 2024

The epicentral region of earthquakes is typically where liquefaction-related damage takes place. To determine the maximum distance, such as maximum epicentral distance (R_e), maximum fault distance (R_f), or maximum hypocentral distance (R_h), at which an earthquake can inflict damage, given its magnitude, this study, using a recently updated global liquefaction database, multiple ML models are built to predict the limiting distances (R_e, R_f, or R_h) required for an earthquake of a given magnitude to cause damage. Four machine learning models LSTM (Long Short-Term Memory), BiLSTM (Bidirectional Long Short-Term Memory), CNN (Convolutional Neural Network), and XGB (Extreme Gradient Boosting) are developed using the Python programming language. All four proposed ML models performed better than empirical models for limiting distance assessment. Among these models, the XGB model outperformed all the models. In order to determine how well the suggested models can predict limiting distances, a number of statistical parameters have been studied. To compare the accuracy of the proposed models, rank analysis, error matrix, and Taylor diagram have been developed. The ML models proposed in this paper are more robust than other current models and may be used to assess the minimal energy of a liquefaction disaster caused by an earthquake or to estimate the maximum distance of a liquefied site provided an earthquake in rapid disaster mapping.

• Journal of International Society for Simulation Surgery
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• 제2권1호
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• pp.26-32
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• 2015

Purpose When a surgeon examines the morphology of skull of patient, locations of craniometric landmarks of 3D computed tomography(CT) volume are one of the most important information for surgical purpose. The locations of craniometric landmarks can be found manually by surgeon from the 3D rendered volume or 2D sagittal, axial, and coronal slices which are taken by CT. Since there are many landmarks on the skull, finding these manually is time-consuming, exhaustive, and occasionally inexact. These inefficiencies raise a demand for a automatic localization technique for craniometric landmark points. So in this paper, we propose a novel method through which we can automatically find these landmark points, which are useful for surgical purpose. Materials and Methods At first, we align the experimental data (CT volumes) using Frankfurt Horizontal Plane (FHP) and Mid Sagittal Plane(MSP) which are defined by 3 and 2 cranial landmark points each. The target landmark of our experiment is the anterior nasal spine. Prior to constructing a statistical cubic model which would be used for detecting the location of the landmark from a given CT volume, reference points for the anterior nasal spine were manually chosen by a surgeon from several CT volume sets. The statistical cubic model is constructed by calculating weighted intensity means of these CT sets around the reference points. By finding the location where similarity function (squared difference function) has the minimal value with this model, the location of the landmark can be found from any given CT volume. Results In this paper, we used 5 CT volumes to construct the statistical cubic model. The 20 CT volumes including the volumes, which were used to construct the model, were used for testing. The range of age of subjects is up to 2 years (24 months) old. The found points of each data are almost close to the reference point which were manually chosen by surgeon. Also it has been seen that the similarity function always has the global minimum at the detection point. Conclusion Through the experiment, we have seen the proposed method shows the outstanding performance in searching the landmark point. This algorithm would make surgeons efficiently work with morphological informations of skull. We also expect the potential of our algorithm for searching the anatomic landmarks not only cranial landmarks.

• 한국지리정보학회지
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• 제23권4호
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• pp.156-172
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• 2020

본 연구는 대상도로인 내부순환로에 대해 태양복사모델(SOlar and LongWave Environmental Irradiance Geometry-model, SOLWEIG)을 통해 산출한 도로의 그림자 패턴을 사용하여 항상 그늘이 지는 음영지역을 살펴보고, 열수지법을 기반으로 한 노면온도예측모델(road surface temperature prediction model, 이하 RSTPM)과 SOLWEIG 모델을 연계하여 고해상도의 태양복사정보를 활용한 도로의 노면온도를 예측하고자 하였다. 우선, 그림자 패턴 및 복사플럭스 산출의 정확도를 높이기 위하여 안개, 구름, 강수 등의 영향을 최소화할 수 있는 사례일을 선정하여, 고도 및 지형의 효과에 따른 그림자의 영향을 살펴보았다. 그 결과, 터널 입출구와 고도가 높은 지역에서 그림자 영역이 오래 지속되었고, 그림자의 영향을 많이 받는 구간의 복사량 감소가 뚜렷하게 나타났다. 이는 노면온도 예측결과에 반영되어 지형적으로 개방된 지점에서는 노면온도가 높게 예측되고, 고도가 높은 지점들은 그렇지 않은 지점에 비해 상대적으로 낮게 예측되었다. 본 연구의 결과는 겨울철 기상상황에 따른 도로 결빙구간을 예측하여 도로 관리자 및 운전자의 의사결정 자료로서의 활용이 기대된다.

• 한국실내디자인학회논문집
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• 제23권2호
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• pp.51-61
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• 2014

Aesthetics of use for modern people can be regarded as being weighted toward universal and rational function since it has focused on an 'automation and efficiency' and 'smartness' in terms of technological and human engineering position. Thus, aesthetics of use as an individual agent has remained in minimal level. This study attempts to seek conceptual model of design regarding the behavior of users from the systematization of critical theories about the usability. To do that, 'HERTZAIN TALES' written by Anthony Dune and the concept and system of Droog Design have been used as a core standard. In line with the various experiments by artist groups such as Fluxus, Memphis group and the work of product semantics, and inherent characteristics of Droog design, which has surfaced from the 1990s, concepts that has mentioned in the Hertzain tales have been organized into main texts. By overcoming cognitive bias inherent in the material culture and by overcoming an existing usability based on immateriality and dialectic solution, the autonomy of critical design and instrumentality of Droog design have been systemized. By interpreting the design aspect of 12 pieces that have been submitted to the RE;MIND section, the core of this study, it has been confirmed that conceptual and critical design's aesthetics of use From the interpretation of the design aspect of 12 pieces that have been submitted to the RE;MIND section, the core of this study, it has been confirmed that conceptual and critical design's aesthetics of use has established the autonomy and independence of the behavior of users, created functional articulation of materials and secured new conceptual model and thus, could be an effective methodical clue for creating an emergent design.

• 통상정보연구
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• 제16권4호
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• pp.171-190
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• 2014

기술발전에 의한 전자제품의 짧은 소비주기는 폐가전제품의 재활용 처리라는 국제적인 환경 문제를 유발시키고 있다. 인도나 중국과 같이 경제력과 소비수준이 급격히 높아지는 국가들에서는 폐가전제품의 급증이 사회적 이슈가 되고 있다. 이들 나라에서는 대부분의 폐전자제품이 적절하지 못한 방식(uncontrolled recycling)으로 처리됨으로써 심각한 환경오염과 건강문제를 야기하고 있다. 국내의 경우도 이들 국가와 크게 다르지 않다. 국내의 경우 기존의 지역별 혹은 개별 기업 수준에서 재활용센터가 운영 중에 있으나, 대부분 일일 처리한도를 초과하여 운영되고 있어서 잉여 폐전자제품의 처리방안에 대한 고민이 시급한 현실이다. 이에, 본 연구에서는 비용과 이동거리 관점에서 재활용센터 입지를 재조정함으로써 보다 재처리를 보다 효율화 할 수 있는 수리모형을 개발, 제안해 보고자 한다. 국내 특정지역의 실제 폐전자제품과 재처리센터 데이터를 활용하여 제안된 최적화 입지 모형을 검증함으로써 국내는 물론 비슷한 문제를 가진 다른 국가의 재처리 문제 개선에도 도움을 주고자 한다.

• Asian Journal of Atmospheric Environment
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• 제10권4호
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• pp.179-189
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• 2016

Here we evaluated the effect of using water retentive pavement or WRP made from fly ash as material for main street in a real city block. We coupled computational fluid dynamics and pavement transport (CFD-PT) model to examine energy balance in the building canopies and ground surface. Two cases of 24 h unsteady analysis were simulated: case 1 where asphalt was used as the pavement material of all ground surfaces and case 2 where WRP was used as main street material. We aim to (1) predict diurnal variation in air temperature, wind speed, ground surface temperature and water content; and (2) compare ground surface energy fluxes. Using the coupled CFD-PT model it was proven that WRP as pavement material for main street can cause a decrease in ground surface temperature. The most significant decrease occurred at 1200 JST when solar radiation was most intense, surface temperature decreased by $13.8^{\circ}C$. This surface temperature decrease also led to cooling of air temperature at 1.5 m above street surface. During this time, air temperature in case 2 decreased by $0.28^{\circ}C$. As the radiation weakens from 1600 JST to 2000 JST, evaporative cooling had also been minimal. Shadow effect, higher albedo and lower thermal conductivity of WRP also contributed to surface temperature decrease. The cooling of ground surface eventually led to air temperature decrease. The degree of air temperature decrease was proportional to the surface temperature decrease. In terms of energy balance, WRP caused a maximum increase in latent heat flux by up to $255W/m^2$ and a decrease in sensible heat flux by up to $465W/m^2$.