• 제목/요약/키워드: standard measurement methods

검색결과 873건 처리시간 0.031초

용수중(用水中) 세균계수(細菌計數)를 위한 형광검경법(螢光檢鏡法)의 응용(應用) (Application of Epifluorescence, Microscopy for Measurement of Bacterial Population in Water Supplies)

  • 이영환;신승이
    • 한국환경농학회지
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    • 제1권1호
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    • pp.48-52
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    • 1982
  • 수중미생물(水中微生物)의 계수방법(計數方法)은 크게 둘로 나누인다. 첫째 방법(方法)은 replicon개염(槪念)에 기초(基礎)를 둔 것으로 살아있는균(菌)과 죽은 균(菌)을 구별할 수 있으나 사용(使用)되는 배지(培地)가 생리적(生理的)으로 다른 다양(多樣)한 세균(細菌)들로 구성된 수중세균(水中細菌)의 생육(生育)에 적합하지 않아서 전(全) 세균수(細菌數)를 계수(計數)할 수 없다. 둘째 방법(方法)은 직접 검경하여 계수(計數)하는 방법(方法)으로 살아있는 균(菌)과 죽은균(菌), 세균(細菌)과 particle의 구별(區別)이 곤란하다. 그러나 최근 세균염색수(細菌染色術)의 발달(發達)로 수중세균(水中細菌)을 육안(肉眼)으로 쉽게 구별(區別)하여 계수(計數)할 수 있는 방법(方法)이 가능(可能)하게 되었다. 이 방법(方法)은 형광현징경(螢光顯徵鏡)을 사용(使用)하여 acridine orange로 염색(染色)된 수중(水中)의 전세균수(全細菌數)를 측정(測定)하는 방법(方法)이다. 따라서 본(本) 연구(硏究)는 상수도원(上水道源)의 세균오염도(細菌汚染度)를 측정(測定)하는데 새로운 방법(方法)으로서 epifluorcscence microscopy를 제시(提示)하는데 있으며 이의 사용성가능여부(使用性可能與否)를 진단(診斷)하기 위해 chlorine과 chloramine을 시료수(試料水)에 처리(處理)하여 경시적으로 세균수(細菌數)를 조사(調査)하여 평판법(平板法)과 비교(比較)하였다. 시료수(試料水)(sample water)의 전세균수(全細菌數)는 형광검경법(螢光檢鏡法)에 의(依)해 정확(正確)히 측정(測定)되었으며 분리능력(分離能力)(resolution)에 있어서 탁월(卓越)하였고 또한 경제적(經濟的)이고도 간편하였다. 그리고 소독살균제(消毒殺菌劑)로는 chloramine이 감소(監素)보다 수중세균(水中細菌)에 미치는 영향(影響)은 훨씬 컸다.

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Effects of variety, region and season on near infrared reflectance spectroscopic analysis of quality parameters in red wine grapes

  • Esler, Michael B.;Gishen, Mark;Francis, I.Leigh;Dambergs, Robert G.;Kambouris, Ambrosias;Cynkar, Wies U.;Boehm, David R.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1523-1523
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    • 2001
  • The wine industry requires practical methods for objectively measuring the composition of both red wine grapes on the vine to determine optimal harvest time; and of freshly harvested grapes for efficient allocation to vinery process streams for particular red wine products, and to determine payment of contract grapegrowers. To be practical for industry application these methods must be rapid, inexpensive and accurate. In most cases this restricts the analyses available to measurement of TSS (total soluble solids, predominantly sugars) by refractometry and pH by electropotentiometry. These two parameters, however, do not provide a comprehensive compositional characterization for the purpose of winemaking. The concentration of anthocyanin pigment in red wine grapes is an accepted indicator of potential wine quality and price. However, routine analysis for total anthocyanins is not considered as a practical option by the wider wine industry because of the high cost and slow turnaround time of this multi-step wet chemical laboratory analysis. Recent work by this ${group}^{l,2}$ has established the capability of near infrared (NIR) spectroscopy to provide rapid, accurate and simultaneous measurement of total anthocyanins, TSS and pH in red wine grapes. The analyses may be carried out equally well using either research grade scanning spectrometers or much simpler reduced spectral range portable diode-array based instrumentation. We have recently expanded on this work by collecting thousands of red wine grape samples in Australia. The sample set spans two vintages (1999 and 2000), five distinct geographical winegrowing regions and three main red wine grape varieties used in Australia (Cabernet Sauvignon, Shiraz and Merlot). Homogenized grape samples were scanned in diffuse reflectance mode on a FOSE NIR Systems6500 spectrometer and subject to laboratory analysis by the traditional methods for total anthocyanins, TSS and pH. We report here an analysis of the correlations between the NIR spectra and the laboratory data using standard chemometric algorithms within The Unscrambler software package. In particular, various subsets of the total data set are considered in turn to elucidate the effects of vintage, geographical area and grape variety on the measurement of grape composition by NIR spectroscopy. The relative ability of discrete calibrations to predict within and across these differences is considered. The results are then used to propose an optimal calibration strategy for red wine grape analysis.

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전동식 부항기에 대한 안전성 및 성능평가 가이드라인 개발연구 (Study on Developing Assessment Guideline for Safety and Performance of Electric Cupping Apparatus)

  • 이승호;김은정;신경훈;남동우;강중원;이승덕;이혜정;이재동;김갑성
    • Journal of Acupuncture Research
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    • 제26권6호
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    • pp.101-110
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    • 2009
  • Objectives : We developed and proposed a guideline for safety and performance assessment of electric cupping apparatus(Class 2 medical device). Methods : We drafted the guideline for safety and performance assessment of electric cupping apparatus by referring the existing standards and guideline, based on online questionnaire for Korean medical doctors and measurement data from commercially available products. Physical dimension of cups and inner vacuum pressure were acquired for the measurement in order to achieve the purposes. Results : This guideline only can be applied to electric cupping apparatus for enhancing blood circulation by employing negative pressure generated by electricity. Seven items of appearance and label, operation test of pump, variation test of input electricity, vacuum level test, vacuum sustain test, cup-size dependent test, noise level test are suggested for evaluation subjects and methods required for electric cupping devices. Requirements for the design and development of electric cupping devices are suggested: vacuum level indicator, vacuum generation rate, pressure control, valve detachment stability, cup comparability, safety measure, surge protection, user friendliness, instruction for use (IFU). Conclusions : We proposed a guideline for safety and performance assessment of electric cupping apparatus to improve the quality of relating products and aid the commercialization of them, by aiming higher industrial competitiveness of the medical device sectors in Korea. Discussion with related institutes such as industry, academy and government is further required. Public hearings also need to be held prior to the establishment of a final guideline and standard.

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코발트전극과 자동시험장치를 이용한 파프리카 양액 내 무기인산 측정 (Determination of Inorganic Phosphate in Paprika Hydroponic Solution using a Laboratory-made Automated Test Stand with Cobalt-based Electrodes)

  • 김학진;손동욱;권순구;노미영;강창익;정호섭
    • Journal of Biosystems Engineering
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    • 제36권5호
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    • pp.326-333
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    • 2011
  • The need for rapid on-site monitoring of hydroponic macronutrients has led to the use of ion-selective electrodes, because of their advantages over spectrophotometric methods, including simple methodology, direct measurement of analyte, sensitivity over a wide concentration range, and low cost. Stability and repeatability of response can be a concern when using multiple ion-selective electrodes to measure concentrations in a series of samples because accuracy might be limited by drifts in electrode potential. A computer-based measurement system could improve accuracy and precision because of both consistent control of sample preparation and easy calibration of sensors. Our goal was to investigate the applicability of a cobalt-based electrode used in conjunction with a laboratory-made automated test stand for quantitative determination of ${PO_4}^-$ in hydroponic solution. Six hydroponic solutions were prepared by diluting highly concentrated paprika hydroponicsolution to provide a concentration range of 1 to 300 ppm $PO_4$-P. A calibration curve relating electrode response to phosphate in paprika hydroponic solution titrated to pH 4 with 0.025M KHP was developed based on the Nikolskii-Eisenman equation with a coefficient of determination ($R^2$) of 0.94. The laboratory-made test stand consisting of three cobalt-based electrodes measured phosphate concentrations similar to those obtained with standard laboratory methods (a regression slope of 0.98 with $R^2$ = 0.80). However, the y intercept was relatively high, 30 ppm, probably due to the relatively large amount of variation present among multiple measurements of the same sample. Further studies on the high variation in EMFs obtained with cobalt electrodes during replicate measurements were required for P estimations comparable to those obtained with standard laboratory instruments.

건설기계 시간당작업량(Q) 산정 개선방안 -펌프준설선 작업효율(E)을 중심으로- (The estimating method of construction workable-quantity per unit time - Focused on Pump-Dredge -)

  • 안방률;태용호;서상욱
    • 한국건설관리학회논문집
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    • 제11권3호
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    • pp.125-133
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    • 2010
  • 국내 공공건설공사 예정가격작성기준에서 제시하는 건설기계의 시간당 작업량(Q)의 중요한 부분을 차지하는 작업효율(E)은 현장여건 등에 따라 차이가 발생하기 때문에 적용기준이 명확해야 한다. 그러나 국내 기준은 정성적인 표현이 사용되며, 이를 판단할 수 있는 기준 또한 포괄적이고 모호하여 설계자의 주관적이고 자의적인 판단에 따라 설계가 이루어지고 있는 실정이다. 본 연구에서는 펌프준설선을 대상으로 국내 외 관련 문헌조사 및 현장실사를 통하여 합리적인 작업효율(E) 제시방법을 제안하고 이로 인해 건설기계의 시간당 작업량 산정방법을 개선하고자 하였다. 문헌조사를 통해 국내기준 또한 일본기준의 형태로 작업효율(E)을 공사구분별, 흙두께, 평면형상, 단면형상, 해상조건 등으로 세분화 시킬 것을 제시하였으며, 이를 판단할 수 있는 기준도 객관화 시킬 수 있는 형태로 개선되어야 할 것을 제시하였다. 또한, 현장조사를 통해 얻어진 산출량을 일본의 예정가격작성기준을 적용하여 계산된 산출량과 비교하여 일본기준의 적정성을 검토하였다. 펌프준설선 (4,476kW)은 배송거리 3,600~6,000m의 시간당 준설량(Q)을 실측하여 표준값인 전동환산(q)을 비교하여, 일본대비 102.3% 수준으로 거의 유사한 결과값을 얻었다. 본 연구를 통해 제시된 각종 자료 및 수치들은 건설기계와 기술의 급속한 발전을 예정가격작성기준에 적용할 수 있는 기초가 될 수 있을 뿐 아니라, 관련 연구의 토대가 될 수 있으리라 기대한다.

불꽃원자 흡수광법에 의한요중 카드뮴 배설량 측정의 지적조건 (Measurement conditions for cadmium in urine by flame atomic absorption spectrophotometry)

  • 최호춘;정규철
    • Journal of Preventive Medicine and Public Health
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    • 제17권1호
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    • pp.269-279
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    • 1984
  • The optimum conditions for measuring cadmium content of less than 0.2ppm by flame atomic absorption spectrophotometry were investigated. The cadmium in urine was extracted by APDC-MIBK for the analysis by atomic absorption spectrophotometry after ashing them by a wet method. 1. Optimum conditions by APDC-MIBK and DDTC-MIBK extractions. The acidic aqueous solution was prepared with appropriate amount of 0.IN nitric acid, 5ml of 25% (W/V) sodium potasstum tartarate, 10ml of saturated ammonium sulfate, and 2ml of 2% APDC(or 1 ml of 5% DDTC) chelating agent. The total volume of solution was adjusted to 55 ml and pH to $2{\sim}10$ (or$7{\sim}10$). The aqueous solution was extracted with 10ml MIBK. Concentration of Triton X-100 did not effect the absorbance for APDC-MIBK extraction of cadmium, but absorbance decreased as the concentration increased for DDTC-MIBK extraction. The sensitivity and detection limits for the cadmium determination from APDC-MIBK extraction were 0.0038ppm and 0.0102, 0.0022ppm and 0.0116 for DDTC-MIBK, and 0.0132ppm and 0.0034 for 0.1N nitric acid. APDC-MIBK and DDTC-MIBK extractions were 3 times higher than 0.1N nitric acid for the sensitivity. 2. Excretion of cadmium in 24-hour urine by APDC-MIBK extraction. Determination of cadmium in urine by atomic absorption spectrophotometry of A.A. (Cd=2 mA) mode and B.C. (Cd=4 mA) mode and B.C. (Cd=4mA, $D_2=20mA$) mode showed some difference (p<0.05). The difference of cadmium determination and recovery according to method of standard additions and standard calibration curve method in urine was not significant (p>0.05, $93.48{\pm}11.78%,\;94.83{\pm}22.00%$). Excretion of cadmium in 24-hour urine collection from normal person and variance analysis within measurement variation was not significant (p>0.05), but between interindividual was significant (0.05). Determination of cadmium content by two different methods of flame atomic absorption spectrophotometry and dithizone colorimetry showed that the results from the two methods can be described by a regression line with a good correlation (y=1.0153x-0.2927, x=Cd by D.C., y=Cd by A.A.S., $r=0.8651^*$, p<0.01).

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ISO 20816 기반 회전기기 진동분석 자동화 알고리즘 개발 (Development of Algorithm for Vibration Analysis Automation of Rotating Equipments Based on ISO 20816)

  • 이재웅;이우귀연;오정석
    • 한국가스학회지
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    • 제28권2호
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    • pp.93-104
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    • 2024
  • 산업현장에서 사용되는 회전기기의 원활한 작동 및 수명연장을 위해서는 설비진단이 필수적이다. 다양한 설비진단의 방법 중 진동진단은 다른 진단방법과 비교하여 불평형(unbalance), 축정렬 불량(misalignment), 베어링 결함(bearing fault), 기어 손상(worn gears), 소음(noise), 공진(resonance) 등 대부분의 초기 결함을 발견할 수 있다. 따라서, 진동분석은 산업현장에서 가장 범용적으로 사용되는 설비진단 방법이며, 설비의 상태를 기반으로 관리하는 예지보전(PdM) 기술로 유용하게 활용된다. 하지만, 진동진단 방법은 기준을 근거로 경험에 의존하여 수행되기 때문에 전문가에 의하여 진행된다. 따라서, 기존에 경험에 의존하여 수행하는 진동진단 방법을 지식화된 코드체계로 구축하여 누구나 쉽게 결함을 판단할 수 있는 시스템을 구축하여 설비의 신뢰성 구축에 기여하고자 한다. 진동측정에 대한 ISO-20816 기준을 근거로 알고리즘을 개발하였고, 석유화학공장 압축기, 수소충전소, 산업용 기계 등 다양한 실증현장에서 진동을 측정한 결과와 개발 시스템을 활용하여 분석한 결과를 비교하여 신뢰성을 검증하였다. 개발된 알고리즘을 통하여 산업현장에서 누구나 회전기기의 상태를 진단하고 결함을 조기에 파악하여 정확한 교체시점에 부품을 교체할 수 있는 예측유지보수(PdM)기술에 기여할 수 있다. 나아가, 정유산업시설, 운송, 생산 시설, 항공시설 등 다양한 산업현장에 적용 시 회전기기의 고장으로 인한 유지보수 비용과 다운타임(down time)의 절감에 이바지할수 있를 것으로 기대된다.

Detecting Incipient Caries Using Front-illuminated Infrared Light Scattering Imaging

  • Kim, Ji-Young;Ro, Jung-Hoon;Jeon, Gye-Rok;Kim, Jin-Bom;Ye, Soo-Young
    • Transactions on Electrical and Electronic Materials
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    • 제13권6호
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    • pp.310-316
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    • 2012
  • A new method for early caries diagnosis was proposed and tested through a home-made optical examination system that used quantitative light fluorescence (QLF) and digital imaging fiber optic transillumination (FOTI) (DIFOTI), with light sources across a wide spectral range, from 350 nm to 1,000 nm. The front-illuminated infrared light scattering image (FIR) showed similar diagnostic abilities to that of DIFOTI. The FIR method was invented based on the observation that caries lesions lose the high transmittance and low scattering properties of benign enamel tissue. There are various methods for the early diagnosis of caries, such as visual examination, exploration, X-ray radiography, QLF, FOTI, and infrared fluorescence (diagnodent). Among them, methods based on optical properties are regarded as having the most potential. A comparative study was performed between the FOTI, QLF, diagnodent, optical coherence tomography, and FIR scattering image methods, using 20 extracted teeth samples with early caries. A scale of lesion measurement based on optical image contrast was proposed. The statistical analysis showed a significant correlation between the DIFOTI and FIR methods (r = 0.35, p < 0.05). However, the QLF and diagnodent methods showed little association with FIR images, as they have different detection principles as compared with FIR. Tomographic images obtained by OCT, using 1,330 nm super luminescent LED as a gold standard of tooth structure, verified that the FOTI and FIR results correctly represented the lack of homogeneity in dental tissue. The newly proposed FIR method attained similar diagnostic results to those of FOTI, but with an easier approach.

Influence of porcelain veneering on the marginal fit of Digident and Lava CAD/CAM zirconia ceramic crowns

  • Pak, Hyun-Soon;Han, Jung-Suk;Lee, Jai-Bong;Kim, Sung-Hun;Yang, Jae-Ho
    • The Journal of Advanced Prosthodontics
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    • 제2권2호
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    • pp.33-38
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    • 2010
  • PURPOSE. Marginal fit is a very important factor considering the restoration's long-term success. However, adding porcelain to copings can cause distortion and lead to an inadequate fit which exposes more luting material to the oral environment and causes secondary caries. The purpose of this study was to compare the marginal fit of 2 different all-ceramic crown systems before and after porcelain veneering. This study was also intended to verify the marginal fit of crowns originated from green machining of partially sintered blocks of zirconia (Lava CAD/CAM system) and that of crowns obtained through machining of fully sintered blocks of zirconia (Digident CAD/CAM system). MATERIALS AND METHODS. 20 crowns were made per each system and the marginal fit was evaluated through a light microscope with image processing (Accura 2000) at 50 points that were randomly selected. Each crown was measured twice: the first measurement was done after obtaining a 0.5 mm coping and the second measurement was done after porcelain veneering. The means and standard deviations were calculated and statistical inferences among the 2 groups were made using independent t-test and within the same group through paired t-test. RESULTS. The means and standard deviations of the marginal fit were $61.52{\pm}2.88{\mu}m$ for the Digident CAD/CAM zirconia ceramic crowns before porcelain veneering and $83.15{\pm}3.51{\mu}m$ after porcelain veneering. Lava CAD/CAM zirconia ceramic crowns showed means and standard deviations of $62.22{\pm}1.78{\mu}m$ before porcelain veneering and $82.03{\pm}1.85{\mu}m$ after porcelain veneering. Both groups showed significant differences when analyzing the marginal gaps before and after porcelain veneering within each group. However, no significant differences were found when comparing the marginal gaps of each group before porcelain veneering and after porcelain veneering as well. CONCLUSION. The 2 all-ceramic crown systems showed marginal gaps that were within a reported clinically acceptable range of marginal discrepancy.

Three-dimensional morphometric analysis of mandibule in coronal plane after bimaxillary rotational surgery

  • Lee, Sung-Tak;Choi, Na-Rae;Song, Jae-Min;Shin, Sang-Hun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제38권
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    • pp.49.1-49.9
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    • 2016
  • Background: The aim of this report is to present a new reference for aesthetic mandible surgery using three-dimensional cone-beam computed tomography-based treatment planning for orthognathic surgery which can be implemented in surgical planning and perioperative procedure. Methods: To make an objective standard for evaluating aesthetic mandibular outline, we make an aesthetic scoring criteria with consideration of asymmetry, broad mandibular border line, and prominent mandibular angle. Two maxillofacial surgeons and two orthodontists rated their aesthetical evaluation from 1 to 5. Experimental group consisting of 47 female and 38 male patients who had rotational orthognathic two-jaw surgery from 2010 to 2011 were chosen according to aesthetic scoring done by two maxillofacial surgeons and two orthodontists. A high aesthetic score (${\geq}16$) means the facial contour is symmetric, with no broad and narrow aesthetic mandible frontal profiles. Control A group consisted of ten female and ten male patients who had no orthognathic surgery experience and low aesthetic score (${\geq}10$). Control B group consisted of ten female and ten male patients who had no orthognathic surgery experience and had anaesthetic mandibular frontal profile and a high aesthetic score (${\geq}16$). The three-dimensional image of the patient was taken from dental cone-beam CT (DCT) scanning (experimental group and control A group: 6 months DCT after surgery, control B group: 1st visit DCT). Each DCT was reformatted to reorient the 3D image using 3D analyzing program (OnDemand3D, cybermed Inc, CA, USA). After selection of 12 landmarks and the construction of reoriented horizontal, vertical, and coronal reference lines, 15 measurements were taken in 3D analysis of frontal mandibular morphology. Afterwards, horizontal and vertical linear measurements and angular measurements, linear ratio were obtained. Results: Mean $Go^{\prime}_{Rt}-Me^{\prime}-Go^{\prime}_{Lt}$ angular measurement was $100.74{\pm}2.14$ in female patients and $105.37{\pm}3.62$ in male patients. These showed significant difference with control A group in both genders. Ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}-Me^{\prime}$ length to some linear measurements (ratio of $Me^{\prime}-Cd^{\prime}_{Rt}Cd^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Me^{\prime}-Go^{\prime}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$) showed significant difference with control A group in both genders. Conclusion: This study was intended to find some standard measurement of mandible frontal view in 3D analysis of aesthetic patient. So, these potential measurement value may be helpful for orthognathic treatment planning to have more aesthetic and perspective outcomes.