• 제목/요약/키워드: random elements

검색결과 261건 처리시간 0.03초

A Portable Mirror Stand for Clinical Facial Photo Documentation

  • Supit, Laureen;Prasetyono, Theddeus O.H.
    • Archives of Plastic Surgery
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    • 제42권3호
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    • pp.356-360
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    • 2015
  • In plastic surgery, patient photography is a vital component of clinical, educational, legal, and research documentation. Optimal acquisition of photographic data requires a dedicated photography studio or a three-dimensional anatomic scanner, both of which are financially impractical for most clinicians. Simplified photo standardization is proposed for use in random clinical settings by using a portable device called the Mirror Stand (MirS). This model device aims to mimic a studio environment by incorporating the basic elements of producing consistent photographs. The pilot MirS is designed for facial photography. Images of 40 random subjects were obtained using the MirS with three different cameras. Real anthropometric measurements of each subject were collected, compared with the photographic measurements, and analyzed. In this study, all three cameras produced equally reliable measurements. Actual facial measurements were comparable to the photogrammetric measurements obtained from photographs taken using the MirS. A constant formula was derived; it allowed the conversion of photographic values into real anthropometric values. The MirS produced consistent photographs with respect to the measurements. The photographs obtained could be translated reliably into their real anthropometric measurements. Therefore, the MirS can be applied in daily practice, providing an efficient alternative for obtaining a standard justifiable photograph.

A New Random SPWM Technique for AC-AC Converter-Based WECS

  • Singh, Navdeep;Agarwal, Vineeta
    • Journal of Power Electronics
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    • 제15권4호
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    • pp.939-950
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    • 2015
  • A single-stage AC-AC converter has been designed for a wind energy conversion system (WECS) that eliminates multistage operation and DC-link filter elements, thus resolving size, weight, and reliability issues. A simple switching strategy is used to control the switches that changes the variable-frequency AC output of an electrical generator to a constant-frequency supply to feed into a distributed electrical load/grid. In addition, a modified random sinusoidal pulse width modulation (RSPWM) technique has been developed for the designed converter to make the overall system more efficient by increasing generating power capacity and reducing the effects of inter-harmonics and sub-harmonics generated in the WECS. The technique uses carrier and reference waves of variable switching frequency to calculate the firing angles of the switches of the converter so that the three-phase output voltage of the converter is very close to a sine wave with reduced THD. A comparison of the performance of the proposed RSPWM technique with the conventional SPWM demonstrated that the power generated by a turbine in the proposed approximately increased by 5% to 10% and THD reduces by 40% both in voltage and current with respect to conventional SPWM.

Application of ChatGPT text extraction model in analyzing rhetorical principles of COVID-19 pandemic information on a question-and-answer community

  • Hyunwoo Moon;Beom Jun Bae;Sangwon Bae
    • International journal of advanced smart convergence
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    • 제13권2호
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    • pp.205-213
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    • 2024
  • This study uses a large language model (LLM) to identify Aristotle's rhetorical principles (ethos, pathos, and logos) in COVID-19 information on Naver Knowledge-iN, South Korea's leading question-and-answer community. The research analyzed the differences of these rhetorical elements in the most upvoted answers with random answers. A total of 193 answer pairs were randomly selected, with 135 pairs for training and 58 for testing. These answers were then coded in line with the rhetorical principles to refine GPT 3.5-based models. The models achieved F1 scores of .88 (ethos), .81 (pathos), and .69 (logos). Subsequent analysis of 128 new answer pairs revealed that logos, particularly factual information and logical reasoning, was more frequently used in the most upvoted answers than the random answers, whereas there were no differences in ethos and pathos between the answer groups. The results suggest that health information consumers value information including logos while ethos and pathos were not associated with consumers' preference for health information. By utilizing an LLM for the analysis of persuasive content, which has been typically conducted manually with much labor and time, this study not only demonstrates the feasibility of using an LLM for latent content but also contributes to expanding the horizon in the field of AI text extraction.

Improved Thermal Stability of a Novel Acidophilic Phytase

  • Byung Sam Son;So Hyeong Kim;Hye-Young Sagong;Su Rin Lee;Eun Jung Choi
    • Journal of Microbiology and Biotechnology
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    • 제34권5호
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    • pp.1119-1125
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    • 2024
  • Phytase increases the availability of phosphate and trace elements by hydrolyzing the phosphomonoester bond in phytate present in animal feed. It is also an important enzyme from an environmental perspective because it not only promotes the growth of livestocks but also prevents phosphorus contamination released into the environment. Here we present a novel phytase derived from Turicimonas muris, TmPhy, which has distinctive structure and properties compared to other previously known phytases. TmPhy gene expressed in the Pichia system was confirmed to be 41 kDa in size and was used in purified form to evaluate optimal conditions for maximum activity. TmPhy has a dual optimum pH at pH3 and pH6.8 and exhibited the highest activity at 70℃. However, the heat tolerance of the wildtype was not satisfactory for feed application. Therefore, random mutation, disulfide bond introduction, and N-terminal mutation were performed to improve the thermostability of the TmPhy. Random mutation resulted in TmPhyM with about 45% improvement in stability at 60℃. Through further improvements, a total of three mutants were screened and their heat tolerance was evaluated. As a result, we obtained TmPhyMD1 with 46.5% residual activity, TmPhyMD2 with 74.1%, and TmPhyMD3 with 66.8% at 80℃ heat treatment without significant loss of or with increased activity.

Pit에 의한 부분반사율을 갖는 항내에서의 다방향 불규칙 파랑회절에 관한 연구 (The Multidirectional Random Wave Diffraction in a Partial-Reflecting Harbor due to a Submarine Pit)

  • 김성덕;이홍식
    • 한국해안·해양공학회논문집
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    • 제20권3호
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    • pp.291-299
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    • 2008
  • 본 연구는 항만입구(항구) 부근에 항로가 준설되었을 경우, 항내 및 항구 주위에서 회절되는 파랑장의 효과를 예측하기 위한 것이다. 본 연구에서 항만경계의 단면은 부분반사 혹은 완전반사로 고려한다. 본 수치모의 계산은 자동경계요소 알고리즘으로 Pit 및 항만경계의 경계요소(segment)를 이산화한 경계요소법에 의해 실시하였다. 입사파 조건은 Mitsuyasu의 주파수스펙트럼과 방향함수의 이산화된 형태를 사용하여 특정화하였다. 본 계산치의 결과는 기존에 발표된 실험치의 결과와 잘 일치하였다. Pit 설치의 효과에 의해 파고감소의 비율은 완전반사 경계의 경우에 대하여 약 20%, 그리고 부분반사 경계의 경우에 대하여 약 10% 정도인 것으로 나타나고 있다.

효율적인 전자문서 관리를 위한 난수 재배열 기반의 키 관리 방법을 이용한 암호화 기법에 관한 연구 (A Study on the Encrypted Scheme Using Key Management Method Based on the Random Number Rearrangement for the Effective E-Document Management)

  • 김태욱;성경상;김정재;민병묵;오해석
    • 정보처리학회논문지C
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    • 제16C권5호
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    • pp.575-582
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    • 2009
  • 전자문서의 많은 이점이 있음에도 불구하고 무단 유출, 파괴, 분실, 훼손의 위험이 상존하고 있다. 불법위조, 변조, 멸실로 부터 전자문서를 보호하기 위한 기술들이 절실히 요구되고 있다. 전자문서를 대상으로 하는 다양한 보안 기술들이 개발되어 있으나, 대부분 위 변조 및 부인 방지에 치중되어 있다. 본 논문에서는 기존 전자문서 관리시스템에 적용하고 있는 암호화 기술의 문제점을 제시하고, 전자문서 보호를 위한 암호화 알고리즘의 효율적 적용 방안을 통해 문제를 개선하고자 한다. 논문에서 제안하는 난수 재배열 방법을 이용한 키 관리 방안을 적용한 암호화 방식과 기존 전자문서 암호화 시스템과의 비교법에 의한 성능평가를 위해 중요 요소들을 비교 평가 수행하였으며, 안정성과 효율성 두 가지 측면에서 개선된 결과를 얻을 수 있었다.

층화추출과 계통추출을 이용한 효율적인 보조정보 사용 (Efficient Use of Auxiliary Information through the Stratified Sampling and Systematic Sampling Design)

  • 김관수;박민규
    • 한국조사연구학회지:조사연구
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    • 제10권1호
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    • pp.155-168
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    • 2009
  • 표본설계 단계에서 이용 가능한 보조정보가 있는 경우 효율적인 표본추출방법으로 층화추출법이 흔히 고려된다. 특별히 층화변수로 이용할 수 있는 변수가 많은 경우 전체 층의 숫자가 커지게 되며, 이때 각 층으로부터 한 단위를 추출하는 층 표본크기가 1인 층화추출이 효율적임이 알려져 있다. 그러나 각 층으로부터 하나의 추출단위를 추출하는 층 표본크기가 1인 층화추출의 경우 불편 분산 추정량의 계산이 불가능하다. 불편 분산 추정량의 계산은 층의 수를 줄이고 각 층으로부터 두 개의 표본추출단위를 표집하는 층 표본크기가 2인 층화추출에서 가능하나 중요 층화변수가 누락될 경우 층 표본크기가 1인 층화추출에 비해 그 효율성이 떨어진다. 본 연구에서는 Park & Fuller(2008)에 의해 제시된 층 표본크기가 2인 균형 층화추출과 호르비츠-톰슨 추정량의 불편 분산 추정량을 살펴보고, 모의실험을 통하여 여러 가지 층화추출법과 계통추출법을 비교한다. 또한 제시된 표본추출법을 2006년 청년패널 자료에 적용하여 그 효율성을 평가한다.

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Development of a Genome-Wide Random Mutagenesis System Using Proofreading-Deficient DNA Polymerase ${\delta}$ in the Methylotrophic Yeast Hansenula polymorpha

  • Kim, Oh Cheol;Kim, Sang-Yoon;Hwang, Dong Hyeon;Oh, Doo-Byoung;Kang, Hyun Ah;Kwon, Ohsuk
    • Journal of Microbiology and Biotechnology
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    • 제23권3호
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    • pp.304-312
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    • 2013
  • The thermotolerant methylotrophic yeast Hansenula polymorpha is attracting interest as a potential strain for the production of recombinant proteins and biofuels. However, only limited numbers of genome engineering tools are currently available for H. polymorpha. In the present study, we identified the HpPOL3 gene encoding the catalytic subunit of DNA polymerase ${\delta}$ of H. polymorpha and mutated the sequence encoding conserved amino acid residues that are important for its proofreading 3'${\rightarrow}$5' exonuclease activity. The resulting $HpPOL3^*$ gene encoding the error-prone proofreading-deficient DNA polymerase ${\delta}$ was cloned under a methanol oxidase promoter to construct the mutator plasmid pHIF8, which also contains additional elements for site-specific chromosomal integration, selection, and excision. In a H. polymorpha mutator strain chromosomally integrated with pHIF8, a $URA3^-$ mutant resistant to 5-fluoroorotic acid was generated at a 50-fold higher frequency than in the wild-type strain, due to the dominant negative expression of $HpPOL3^*$. Moreover, after obtaining the desired mutant, the mutator allele was readily removed from the chromosome by homologous recombination to avoid the uncontrolled accumulation of additional mutations. Our mutator system, which depends on the accumulation of random mutations that are incorporated during DNA replication, will be useful to generate strains with mutant phenotypes, especially those related to unknown or multiple genes on the chromosome.

메탄 가스 기반 가스 누출 위험 예측을 위한 다변량 특이치 제거 (Multivariate Outlier Removing for the Risk Prediction of Gas Leakage based Methane Gas)

  • 홍고르출;김미혜
    • 한국융합학회논문지
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    • 제11권12호
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    • pp.23-30
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    • 2020
  • 본 연구에서는, 천연가스(NG) 데이터와 가스 관련 환경 요소 간의 관계를 기계학습 알고리즘을 사용하여 가스 누출 데이터를 직접 측정하지 않고 가스 누출 위험 수준을 예측하였다. 이번 연구는 서버가 제공하는 오픈 데이터인 IoT 기반 원격 제어 피카로(Picarro) 가스 센서 사양을 기반으로 사용했다. 천연 가스는 공기 중으로 누출이 되며, 대기 오염, 환경, 그리고 건강에 큰 문제가 된다. 본 연구에서 제안하는 방법은 천연 가스의 누출 위험 예측을 위한 랜덤 포레스트(Random Forest) 분류 기반 다변량 특이치 제거 방법이다. 비지도 k-평균 클러스터링 후에 실험 데이터 집합은 불균형 데이터이다. 따라서 우리는 제안된 모델이 중간과 높은 위험 수준을 가장 잘 예측할 수 있다는 점에 초점을 맞춘다. 이 경우 각 분류 모델에 대한 수신자 조작 특성(ROC) 곡선, 정확도, 평균 표준 오차(MSE)를 비교했다. 실험 결과로 정확도, 수신자 조작 특성의 곡선 아래 영역(AUC, Area Under the ROC Curve), MSE가 각각 MOL_RF의 경우 99.71%, 99.57%, 및 0.0016의 결과 값을 얻었다.

북경(北京)과 상해(上海에)에 거주하는 중국(中國) 성인여성(成人女性)의 체형 유형화(體形 類型化)에 관한 연구(硏究) -지수(指數)를 중심(中心)으로- (A Study on Classification of Chinese Women - Focusing on the Body Index -)

  • 김은희;손희순
    • 패션비즈니스
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    • 제11권5호
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    • pp.124-135
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    • 2007
  • To understand tendency of body shapes of Chinese women who reside in Beijing and Shanghai for improving the match of exported clothes to China, this categorizes the bodies by extracting the elements of the objects and understanding body promotion. To categorize the subject by not size factor but form factor, data were compared and analyzed mainly with index based on measurement of the body. This selected specimen as 1381 of Chinese women from 19 to 50 selected in random sampling in Shanghai and Beijing from 23th, June to 7th August in 2004. 1. Chinese women is generally separated in 7.09 parts and upper body including waist shapes round. 2. The elements indicating the women's physical properties are obesity, the size of upper part, front shape, side shape, shoulder and back shape, perpendicular size and lower part length, body shape. 3. The Chinese are categorized by three factors. Normal shape which is not both fat and skinny, records the highest in the ranking.