• 한국철도학회논문집
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• 제7권3호
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• pp.200-207
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• 2004

Theoretical study has been conducted to clarify pressure characteristics of KTX (Korea Train eXpress) in tunnel. The severe pressure change in tunnel may give rise to the ear-discomfort for passenger and fatigue for car body. Critical tunnel lengths which are induced by x-t diagram analysis can be applied to the experimental results measured by using the running test with atmospheric pressure sensors and portable data acquisition system in previous study. In this study, the tunnels from 200m to 4000m in length have been chosen for the investigation of tunnel length effects. We found that there are similar patterns of external pressure change for each critical tunnel length. The critical tunnel lengths are governed by train speed, train length and sonic velocity. And, the patterns of pressure wave in tunnel are classified into eight groups.

• International Journal of Railway
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• 제1권4호
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• pp.169-174
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• 2008

Experimental study has been conducted to clarify the internal and external pressure variation characteristics for KTX(Korea Train eXpress) passing through tunnel. Abrupt pressure variation gives rise to the ear-discomfort for passenger and fatigue for car body. In this study, the internal and external pressure variation are measured by using KTX real train experiment and on-board portable data acquisition system in Gyeongbu high speed commercial line. The tunnels from 200 m to 4000 m in length are chosen for the investigation of tunnel length effects. From the results of experiment, the internal pressure variation rate for all the test tunnels is lower than the standard criteria of 200 Pa/s. And, the critical tunnel lengths for pressure wave pattern are classified into 7 groups by using the theoretical L-t diagram analysis.

• 한방재활의학과학회지
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• 제24권1호
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• pp.125-131
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• 2014

We researched two patients with ear fullness after traffic accident. We diagnosed the patients' symptom as referred pain caused by clavicle branch of sternocleidomastoid (SCM) muscle. So, acupunture therapy and SCENAR therapy were used to treat the patients. We measured their discomfort by visual anlog scale (VAS) before and after treatment. As a result, the patients improved remarkably and VAS score was declined sharply when we applied acupuncture therapy and SCENAR therapy on clavicle branch of SCM. Therefore, we are certain that ear fullness can be caused by clavicle branch of SCM after traffic accident. It shows dramatical and satisfactory progress by acupuncture therapy and SCENAR therapy to relax shortening of clavicle branch of SCM.

• 대한의용생체공학회:의공학회지
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• 제26권5호
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• pp.309-317
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• 2005

It is expected that fully-implantable middle-ear hearing devices (FIMEHDs) will soon be available with the advantages of complete concealment, easy surgical implantation, and low power operation to resolve the problems of semi-implantable middle-ear hearing devices (SIMEHDs) such as discomfort of wearing an external device and replacement of battery. Over the last 3 years, a Korean research team at Kyungpook National University has developed an FIMEHD called ACRHS-1 based on a differential floating mass transducer (DFMT). The main research focus was functional improvement, the establishment of easy surgical procedures for implantation, miniaturization, and a low-power operation. Accordingly, this paper reviews the overall system architecture, functions, and experimental results for ACRHS-1 and its related accessories, including a wireless battery charger and remote controller.

• 한국전산유체공학회지
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• 제20권3호
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• pp.62-69
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• 2015

Pressure change inside cabin as well as in tunnel has been calculated to assess the passenger pressure comfort of high-speed train. $C-STA^{TM}$, a CFD program based on axi-symmetric Navier-Stokes equation and Roe's FDS has been used to simulate the pressure change in tunnel during a high-speed train passing through it. To present the relative motion between the train and the tunnel, a modified patched grid scheme based on the structured grid system has been employed. The simulation program has been validated by comparing the simulation results with field measurements. Extensive parametric study has been conducted for various train speed, tunnel cross-sectional area and tunnel length to the pressure change in cabin. KTX-Sancheon(KTX2) high-speed train has been chosen for simulation and the train speed have been varied from 200 km/h to 375 km/h. The tunnel length has been varied from 300 m to 7.5 km and tunnel area from $50m^2$ to $120m^2$. Total 504 simulations have been conducted varying the parameters. Based on the database produced from the parametric simulations, minimum tunnel cross-sectional area has been surveyed for various train speeds based on Korean regulation on pressure change in cabin.

• 대한치과의사협회지
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• 제57권4호
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• pp.204-212
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• 2019

Introduction : Patients with temporomandibular disorder may have various ear-related symptoms. If an excessive load is applied to the ear area due to the skeletal shape of the mandibular condyle or malposition of the disc, an auditory problems may occur. Case report : The patient was referred to our clinic due to the suspicion of temporomandibular disorder from the local otorhinolaryngology clinic. A few days ago, his right ear could not be heard. MRI showed that the left TMJ disc was anterior displacement with reduction, the right TMJ disc was anteromedial displacement without reduction. Also Right mandibular condyle showed sclerotic bone change, subchondral cyst and was compressing the frontal wall of the ear on MRI view. Right TMJ arthroplasty was done under the diagnosis of right TMJ osteoarthritis and osteochondroma. Postoperative intermaxillary fixation was done with SAS screw and elastics for 2 weeks. One month after the operation, hearing and TMJ discomfort were recovered without any complications. Conclusions As seen in this case, hearing loss due to benign tumor-like lesions of the temporomandibular joint should be treated surgically to restore the TMJ function and hearing.

• 한국임상보건과학회지
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• 제9권1호
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• pp.1462-1468
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• 2021

Purpose; The purpose of this study is to objectively identify and quantify the wearer's feelings of wearing glasses. Methods: The temperature of the skin on the nose ridges and ear, and the area where the glasses were seated, was measured using a thermal imaging camera. Results: Before wearing the glasses, the temperature of the skin surface on the nasal ridge was 34.908 ± 0.875 ℃ and the temperature of the ear region was determined as 31.981 ± 0.549 ℃. The changed temperature measured at 5 minutes later after taking off the glasses showed that the nasal ridge was determined as 35.467 ± 0.342 ℃ and the ear area was determined as 32.994 ± 0.412 ℃ (p<0.05). Conclusions: In this experiment, it was revealed that the glasses cause discomfort and heat in the fitting area. It was the first attempt to study objectively and scientifically. Analysis of frame fitting points by using thermal camera is expected to be helpful when consulting a sensitive person about changes in the fit of glasses.

• 한국의류학회지
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• 제40권1호
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• pp.114-130
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• 2016

This research provides practical data to develop UV protection masks and dust protection masks. It surveyed uncomfortable factors and significant characteristics for masks. It used 653 subjects 20-79 years old and performed the research from April to May in 2014. Wearing masks at outdoor activities is not widely popular yet, but golf players, mountaineers and old people were quite interested in masks. People mainly wore a basic shape mask, but main age group of each mask shape was different. People usually prioritized the protection function and comfort of wearing over design; however, women, young generation and people attending to outdoor activities longer than 1 hour considered design quite important. People going on picnic or camping consider mask characteristics most important. Therefore, various mask shapes and protective functions should be developed to reflect consumer needs. Meanwhile, the discomfort levels of masks were not too high, but old people felt more discomfort than young people. The most discomfort factors were 'other's eye', 'distracting face movement' and 'feeling of foreign object'. They also mentioned falling problem of C shape mask and short-rib shape mask, and asked for a 'tighter fit' at the ear.

• 대한두개안면성형외과학회지
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• 제20권6호
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• pp.354-360
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• 2019

Background: Keloids are benign fibro-proliferative lesion, related to excessive inflammatory reactions in certain anatomical areas, including the auricles. Their specific etiology remains unclear; nonetheless they exhibit tumor-like characteristics of significant recurrence and cause emotional distress, even with various treatment strategies. We applied intermittent magnetic pressure therapy on ear keloids in combination with surgical excision, and present its effectiveness herein. Methods: Ear keloid patients were treated with surgical excision followed by magnetic pressure therapy. The keloid tissues underwent excision and keloid marginal flaps were utilized for wound closure. Intermittent magnetic pressure therapy was applied 2 weeks after the surgical procedure. The pressure therapy consisted of a 3-hour application and 2-hour resting protocol (9 hr/day), and lasted for 6 months. The results were analyzed 6 months after the therapeutic procedures, using the scar assessment scale. Results: Twenty-two ear keloids from 20 patients were finally reviewed. Among the keloids that completed the therapeutic course, 20 ear keloids out of 22 in total (90.9%) were successfully eradicated. Two patients (2 keloids) exhibited slight under-correction. Postoperative complications such as wound dehiscence or surgical site infection were not noted. The scar assessment scale demonstrated a significant improvement in each index. The intermittent pressure therapy led to patient compliance, and avoided pressure-related pain and discomfort. Conclusion: Excision followed by intermittent pressure application using a magnet successfully reduced the burden of fibro-proliferative keloids, and had good patient compliance. The role of intermittent pressure application and resting should be studied with regard to keloid tissue remodeling.

• 한국철도학회논문집
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• 제15권5호
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• pp.436-441
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• 2012

열차가 터널에 고속으로 진입하면, 압력파가 발생한다. 열차 선두부의 진입에 의하여 발생한 압축파는 터널을 따라 진행되어 터널 출구에서 반사되어 팽창파로 되돌아오며, 후미부의 진입에 의하여 발생한 팽창파도 터널을 따라 전파되어 터널 출구에서 압축파로 반사되어 터널 입구로 되돌아 온다. 열차 선두부 및 후미부에 의하여 발생한 이러한 압력파는 터널 입구 및 출구에서 각각 반사되어 터널 내부를 왕복하며, 차량 객실에 탑승한 승객들에게는 이명감을 일으키고, 터널 출구에서는 환경소음의 일종인 미기압파를 발생시킨다. 터널에서의 큰 압력 변동은 터널의 최적 단면적 설계에도 주요 인자로 고려되고 있으며, 차체의 반복 피로 하중으로 작용하므로, 이에 대한 정량적 및 정성적 분석이 필요하다. 본 연구에서는 고정 격자계를 이용한 특성 해법을 개발하였으며, KTX를 이용한 실차 시험 결과와 비교하였으며, 해석 결과는 시험 결과와 잘 일치하였다.