• 대한소아치과학회지
• /
• 제51권1호
• /
• pp.55-65
• /
• 2024

This study aimed to assess the accuracy of tooth widths, intermolar widths, and arch lengths acquired through two intraoral scanners, including iTero Element Plus Series (Align Technology, Santa Clara, CA, USA) and Trios 4 (3Shape, Copenhagen, Denmark), specifically on mixed dentition. A total of 30 subjects were divided into 2 groups, each undergoing both alginate impressions and intraoral scanning using either the iTero or Trios scanner. The plaster models were measured with a caliper, while the digital models were measured virtually. In the iTero group, all tooth width measurements exhibited differences compared to the plaster values, except for maxillary left lateral incisors (p = 0.179), mandibular right (p = 0.285), and left (p = 0.073) central incisors. The Trios group did not display significant differences in any of the tooth width measurements. Intermolar width comparisons for both groups indicated differences, except for mandibular primary canine to primary canine values (p = 0.426) in the iTero group. Regarding arch length, the mandibular anterior, maxillary right, and left arch lengths in the iTero group demonstrated larger caliper values than those of iTero. Conversely, in the Trios group, all parameters showed smaller caliper values, especially in upper anterior, maxillary right, mandibular right, and mandibular left arch lengths with significance (p = 0.027, 0.007, 0.003, and 0.047, respectively). Despite the differences between the two groups, digital models might be clinically suitable alternatives for plaster models. Pediatric dentists should carefully assess these differences, as a comprehensive evaluation would result in precise orthodontic treatment planning and favorable outcomes for young patients with mixed dentition.

• 대한인간공학회지
• /
• 제13권1호
• /
• pp.47-58
• /
• 1994

The purpose of this study was to obtain the basic data for a design for comfort wear. The subjects of this study were 197 women's university stu- dents. The characteristics of their body types and the thickness of subcuta- neous fat at eight body sites were measured. The thickness of subcutaneous fat was measured by both Ultrasonics and with a Skinfold Caliper. The cor- relation between their values and the thickness of subcutaneous fat were compared. The relationship between Rohrer Index and the subject's self- conception of their body was also compared. The results were as follows: 1. The measurement of thickness of subcutaneous fat at triceps and scapula was a little lower, in using Skinfold Caliper method, than Ultrasonics method because of the pressure of the caliper. 2. Correlation between percentage of fat in body and body characteristics was high in order of chest girth > weight > abdomen girth. 3. The thickness of subcutaneous 8 body these sites was high in order of thigh > triceps > scapula > abdomen > suprailiac > chest > calf > forearm. Percentage of body fat has a positive correlation with both average thickness of subcutaneous fat and thickness of subcutaneous fat at triceps. 4. Rohrer Index shows a positive correlation between average thickness of subcutaneous fat and percentage of body fat. 5. About half of subjects of this study thought that they were obese although the data proved otherwise.

• 자동차안전학회지
• /
• 제10권3호
• /
• pp.38-44
• /
• 2018

Conventional brake system was used for passenger cars and SUV for a long time. However, the high performance brake system has strongly required because of increase of engine power and customer's favorites etc. In this paper, a new high performance brake system for Europe was proposed. For this system, the high performance caliper and disc were newly developed. The superiorities of the developed high performance brake system were verified via heat capacity, hydraulic stiffness, corrosion and harsh braking mode test. Also, the high performance caliper and disc for the light-weight were applied to AL-Alloy and can obtain the weight reduction effect of 2.9 kg per vehicle. Finally, a developed high performance brake system is expected to be used for realization of the high performance at the same platforms.

• 생명과학회지
• /
• 제20권11호
• /
• pp.1738-1741
• /
• 2010

기존의 동물모델에서 암의 성장은 caliper를 이용하여 고형암 부피를 측정으로써 조사하였으나, 암 조직 속의괴사와 부종으로 인하여 부피측정에 신뢰성이 결여 되어 있다. 이러한 문제점을 해결하기 위해 발광 암세포를 이용하여 광학생체영상적으로 분석하는 방법이 개발 되었다. 본 연구에서는 전립선 발광 암세포를 제조하여 고형암 동물모델에서 B16 발광 암세포와 암 성장을 비교 측정하여 신규발광 암세포를 평가하였다. In vitro에서 세포 수와 발광강도는 높은 상관관계를 보였고($R^2$=0.99), 고형암 동물모델에서 암 성장 측정은 괴사에 의한 오차를 줄였다. 이러한 발광신호를 기반으로 한 측정방법은 caliper의 부피 측정에 비하여 높은 항암효과를 보임으로써 기존의 발광 암세포보다 신규 발광전립선 암세포의 유용성을 증명하였다.

• Tribology and Lubricants
• /
• 제27권4호
• /
• pp.204-208
• /
• 2011

Yaw brakes are used in wind turbines to control the orientation of blades to be perpendicular to the wind. These devices are very important machine elements because they are closely related to the overall efficiency of wind turbines. One unit of yaw brakes is composed of a friction pad and a caliper. In this study, a tangential force between the friction pad and the disk is calculated when the brake is acting in 750 kW wind turbine. Then, stress distribution and the deformation of the caliper are calculated using a finite element analysis. An experimental equipment is also developed to verify the exactness of calculated results. The analytical and experimental results are presented and discussed.

• Tribology and Lubricants
• /
• 제13권4호
• /
• pp.10-17
• /
• 1997

The present study describes an experimental investigation of temperature fluctuations associated with thermal instability. Surface temperatures of brake disk and pad were monitered at various locations in a caliper type brake system during drag braking conditions. It was found that the thermal instability appeared in pad more seriously than in disk. The temperatures at various circumferential positions fluctuate synchronously, whereas the center temperature fluctuates with 180$^{\circ}$ phase difference from the outer and inner radius temperatures. The temperature and amplitude of the temperature perturbations are increased due to the increase of contact area in the center location. It was also found that the thermal instability was dominantly determined by the increase of rotation speed and pressure. And the modification of ventilation path could retard the onset of thermal instability.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2012년도 춘계학술대회 논문집
• /
• pp.461-466
• /
• 2012

Customers want to have more convenient and comfortable vehicle. Motor-on-caliper EPB(Electrical Parking Brake) System is one of the new systems for customer's convenience. It is applied for Midsize vehicle for reducing weight/price compared to cable puller type EPB. In this paper we studied sound quality improvement of motor-on-caliper EPB system. We developed the sound quality index and suggested the interior sound quality target value. To meet the target value cascading target was also suggested. EPB motor vibration level & sound radiation level, vibro-acoustic transfer function level from EPB to interior was defined. To find out effective way of sound quality improvement and find cascading target, TPA(Transfer Path Analysis) was carried out.

• 한국공작기계학회:학술대회논문집
• /
• 한국공작기계학회 2004년도 추계학술대회 논문집
• /
• pp.445-450
• /
• 2004

Recently, many studies have been performed and good results have been reported in literature on the prediction of the brake disk temperature. However, study on the brake fluid temperature is rarely found despite of its importance. In this study, brake fluid temperature is predicted according to material property of brake piston. For the analysis, a typical disk-pad brake system is modeled including the brake disk, pad, caliper, piston and brake fluid. Vehicle deceleration, weight distribution by deceleration, disc-pad heat division and the cooling of brake components are considered in the analysis of heat transfer. Unsteady-state temperature distribution are analyzed by using the finite element method and numerical results are compared with the vehicle test data

• 한국소음진동공학회논문집
• /
• 제24권10호
• /
• pp.749-755
• /
• 2014

The analytical-finite element(FE) squeal model is applied to investigate the squeal propensity associated with contact stiffness of the disc brake system. The system contact stiffness is incorporated into the perturbed equations of motion in the analytical manner where the brake components are modeled by FE method. The results show that the contact stiffness of the friction material and the contact stiffness between the pads and caliper are the influential factors on the squeal propensity. Particularly, the modal instability of the 3200 Hz squeal mode drastically changes with respect to the contact stiffness between the pads and caliper.

• Journal of Periodontal and Implant Science
• /
• 제48권2호
• /
• pp.84-91
• /
• 2018

Purpose: The purpose of this study was to visualize and identify peri-implant bone defects in optical coherence tomography (OCT) images and to obtain quantitative measurements of the defect depth. Methods: Dehiscence defects were intentionally formed in porcine mandibles and implants were simultaneously placed without flap elevation. Only the threads of the fixture could be seen at the bone defect site in the OCT images, so the depth of the peri-implant bone defect could be measured through the length of the visible threads. To analyze the reliability of the OCT measurements, the flaps were elevated and the depth of the dehiscence defects was measured with a digital caliper. Results: The average defect depth measured by a digital caliper was $4.88{\pm}1.28mm$, and the corresponding OCT measurement was $5.11{\pm}1.33mm$. Very thin bone areas that were sufficiently transparent in the coronal portion were penetrated by the optical beam in OCT imaging and regarded as bone loss. The intraclass correlation coefficient between the 2 methods was high, with a 95% confidence interval (CI) close to 1. In the Bland-Altman analysis, most measured values were within the threshold of the 95% CI, suggesting close agreement of the OCT measurements with the caliper measurements. Conclusions: OCT images can be used to visualize the peri-implant bone level and to identify bone defects. The potential of quantitative non-invasive measurements of the amount of bone loss was also confirmed.