• 제목/요약/키워드: Predictable mobility

검색결과 17건 처리시간 0.018초

무선 센서 네트워크에서 예측 가능한 싱크 이동성을 기반으로 한 데이타 전달 프로토콜 (Data Dissemination Protocol based on Predictable Mobility of Sinks in Wireless Sensor Networks)

  • 박수창;이의신;진민숙;최영환;김상하
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제14권3호
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    • pp.276-280
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    • 2008
  • 무선 센서 망에서 이동성 지원을 위한 많은 데이타 전달 프로토콜들이 군인들이나 구조원과 같은 싱크의 이동 궤적이 랜덤하다는 가정 아래서 디자인되어왔다. 하지만, 많은 응용에서, 예를 들면 전쟁 지역에서 작전 상황 중의 군인의 이동 궤적과 같은, 싱크의 이동성은 미리 결정될 수 있다. 본 논문에서, 우리는 싱크들의 예측 가능한 이동성을 고려하여 소스 노드로부터 이동하는 싱크까지 데이타를 우회 없이 직행으로 전달할 수 있는 싱크의 예측 가능한 이동성 기반 데이타 전달 프로토콜을 제안한다. 또한, 우리는 기존의 랜덤한 이동성 기반의 데이타 전달 프로토콜들과의 성능 비교를 통해 예측 가능한 이동성 기반 데이타 전달 프로토콜의 향상성을 증명한다.

헴트 소자의 해석적 직류 모델 (AN ANALYTICAL DC MODEL FOR HEMTS)

  • 김영민
    • ETRI Journal
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    • 제11권2호
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    • pp.109-119
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    • 1989
  • Based on the 2-dimensional charge-control simulation[4], a purely analytical model for MODFET's is proposed. In this model, proper treatment of the diffusion effect in the 2-DEG transport due to the gradual channel opening along the 2-DEG channel was made to explain the enhanced mobility and increased thershold voltage. The channel thickness and gate capacitance are experssed as functions of gate vlotage including subthreshold characteristics of the MODFET's analytically. By introducing the finite channel opening and an effective channel-length modulation, the slope of the saturation region of the I-V curves was modeled. The smooth transition of the I-V curves from linear-to-saturation region of the I-V curves was possible using the continuous Troffimenkoff-type of field-dependent mobility. Furthermore, a correction factor f was introduced to account for the finite transtition section forming between the GCA and the saturated section. This factor removes the large discrepanicies in the saturation region fo the I-V curves presicted by existing 1-dimensional models. The fitting parameters chosen in our model were found to be predictable and vary over relatively small range of values.

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뇌성마비 아동에서 노력성 폐활량에 영향을 미치는 요인 분석에 관한 연구 (Predictive Factors Affected to Forced Vital Capacity in Children with Cerebral Palsy)

  • 남기석;이혜영
    • The Journal of Korean Physical Therapy
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    • 제25권4호
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    • pp.204-209
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    • 2013
  • Purpose: Children with cerebral palsy generally have a high incidence of respiratory problem, resulted from poor coughing, airway clearance problem, respiratory muscle weakness, kyphoscoliosis and so forth. The purpose of this study is to investigate the possible factors that can be affected to forced vital capacity (FVC) in children with cerebral palsy. Methods: Total thirty six children with diplegic and hemiplegic cerebral palsy were recruited in this study. They were evaluated by general demographic data (i.e., age, gender, body mass index (BMI)) and variables related to respiratory functions (i.e., chest mobility, waist mobility, maximal phonation time, and maximum inspiratory/expiratory pressure (MIP/MEP)). The correlation between forced vital capacity and the rested variables were analyzed, and multiple regression with stepwise method was conducted to predict respiratory function, in terms of FVC as the dependent variable, and demographic and other respiratory variables as the independent variable. Results: FVC showed a significant correlation with waist mobility (r=0.59, p<0.01), maximal phonation time (r=0.48, p<0.05), MIP (r=0.73, p<0.01), and MEP (r=0.60, p<0.01). In addition, the multiple regression analysis model indicated that FVC could be predicted by the assessment of each waist mobility and MIP. Conclusion: These finding suggest that respiratory function is related to body size and respiratory muscle strength, and that BMI, waist mobility, and MIP can be predictable factors to affected respiratory function in term of FVC.

학령기 정상 아동의 호흡 특성과 신체 조건에 관한 상관분석 (Analysis of Correlation between Respiratory Characteristics and Physical Factors in Healthy Elementary School Childhood)

  • 이혜영;강동연;김경
    • The Journal of Korean Physical Therapy
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    • 제25권5호
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    • pp.330-336
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    • 2013
  • Purpose: Respiratory is an essential vital component for conservation of life in human, which is controlled by respiratory muscles and its related neuromuscular regulation. The purpose of this study is to assess lung capacity and respiratory pressure in healthy children, and to investigate relationship and predictability between respiratory pressure and other related respiratory functions. Methods: A total of 31 healthy children were recruited for this study. Demographic information and respiratory related factors were assessed in terms of body surface area (BSA), chest mobility, lung capacity, and respiratory pressure. Correlation between respiratory pressure and the rested variables was analyzed, and multiple regression using the stepwise method was performed for prediction of respiratory muscle strength, in terms of respiratory pressure as the dependent variable, and demographic and other respiratory variables as the independent variable. Results: According to the results of correlation analysis, respiratory pressure showed significant correlation with age (r=0.62, p<0.01), BSA (r=0.80, p<0.01), FVC (r=0.80, p<0.01), and FEV1 (r=0.70, p<0.01). In results of multiple regression analysis using the backward elimination method, BSA and FVC were included as significant factors of the predictable statistical model. The statistical model showed a significant explanation power of 71.8%. Conclusion: These findings suggest that respiratory pressure could be a valuable measurement tool for evaluation of respiratory function, because of significant relationship with physical characteristics and lung capacity, and that BSA and FVC could be possible predictable factors to explain the degree of respiratory pressure. These findings will provide useful information for clinical assessment and treatment in healthy children as well as those with pulmonary disease.

저밀도 운용 환경에서의 도심항공교통 분리 기준에 관한 연구 (A Study on the Separation Minima for Urban Air Mobility in Low-Density Operation Environments)

  • 장효석;김도현;김재우;김다니엘;조희덕
    • 한국항행학회논문지
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    • 제27권6호
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    • pp.710-715
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    • 2023
  • 도시화가 가속화되면서 교통 혼잡, 주거 및 환경 문제 등의 사회적 이슈가 도출되고 있다. 이를 해결하기 위해 도심항공교통 (UAM; urban air mobility)과 같은 혁신적인 교통시스템 개발에 관한 연구가 활발하게 진행되고 있다. 초기 저밀도 운항 환경에서 기존의 항공교통시스템에 부담을 주지 않으면서도 안전하게 비행이 이루어져야 하고, 공역을 효율적으로 관리하고 운영하는 능력이 요구된다. 따라서 UAM은 회랑을 통한 경로의 운영으로 예측 가능성을 높여 초기 운영단계에서는 저밀도 상황에서의 운항에 대한 데이터를 축적해 나가는 것이 중요하다. 이를 위해서는 운영하기 전 각종 시뮬레이션을 활용한 시나리오를 생성하여 UAM 기체 간의 잠재적인 충돌 가능성을 예측하고 항공기 간격 즉 분리에 대한 손실 (LoS; loss of separation), 그리고 근접 공중충돌 (NMAC; near mid air collision) 위험에 대한 검토가 필요하다. 항적 난기류는 항공기 간의 안전한 분리를 보장하는 중요한 요소로, 기존 항공교통에서는 활주로와 항로의 분리에 필수적으로 사용되었다. UAM 비행체는 저고도에서 밀집된 공간에서 운영되기 때문에, 항적 난기류에 관한 추가적인 연구가 필요하며, 이를 위해 다양한 데이터를 활용하여 기체의 성능을 정밀하게 분석하고 있다. 본 논문에서는 국내외 연구 결과를 바탕으로 UAM의 분리 기준 설정에 필요한 요구사항과 고려해야 할 사항들을 확인하는 데 초점을 맞추고자 한다.

Surgically assisted rapid palatal expansion with tent screws and a custom-made palatal expander: a case report

  • Park, Kang-Nam;Lee, Chang Youn;Park, In Young;Kim, Jwa Young;Yang, Byoungeun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제37권
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    • pp.11.1-11.5
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    • 2015
  • Rapid palatal expansion(RPE) with the tooth-born appliance is not sufficient to apply to the patients with periodontal problem or insufficient tooth anchorage, and it leads to tipping of the anchorage teeth and increasing teeth mobility and root resorption. To avoid these disadvantages, we present the case using palatal screws and custommade palatal expander. A 23-year-old patient underwent surgically assisted rapid maxillary expansion with the Hyrax expansion using 4 tent screws. The study models were used to measure the pre-/-post surgical width of the anterior and posterior dental arches with a digital sliding caliper. In the result, the custom-made palatal expander with 4 tent screws is suitable for delivering a force to the mid-palatal suture expansion. And it is low cost, small sized and simply applied. The results indicated that maxillary expansion with the custom-made palatal anchorage device is predictable and stable technique without significant complications in patients.

유리피판을 이용한 설재건술의 분석 (Analysis of Free Flap Reconstruction of the Tongue)

  • 강동희;이형철;구상환;박승하;정광윤
    • Archives of Plastic Surgery
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    • 제33권5호
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    • pp.557-562
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    • 2006
  • Purpose: Advanced carcinoma of the tongue is a devastating disease which may cause severe speech or swallowing dysfunction. But, none to date has provided all of the complex functions of the tongue. The purpose of this study is to review our experiences with individuals who underwent glossectomy followed by reconstruction using free tissue transfer. Methods: Between February 1998 and February 2005, twenty-four patients underwent glossectomy followed by free tissue transfer reconstruction. The defects of tongue caused by partial or subtotal glossectomy were reconstructed by means of radial forearm or lateral thigh free flap with nerve innervation. Especially for the patients who underwent total glossectomy, we reconstructed deglutition muscles anatomically with nerve reinnervation, a procedure that allows the grafted muscle to maintain good tongue bulk without obvious atrophy. Results: Patients were reviewed to determine their functional outcome as it related to speech, deglutition, and aspiration. All patients achieved oral intake of a soft diet and acceptable speech. Conclusion: Although reconstruction following glossectomy using free tissue transfer is not ideal, this procedure is safe and reliable, and provides predictable results. A future challenge is the development of a surgical procedure for reconstruction of a tongue that maintains mobility and sensation using neurotized flaps.

Histomorphometry and stability analysis of early loaded implants with two different surface conditions in beagle dogs

  • Kim, Dong-Seok;Kim, Dae-Gon;Park, Chan-Jin;Cho, Lee-Ra
    • The Journal of Advanced Prosthodontics
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    • 제1권1호
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    • pp.10-18
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    • 2009
  • STATEMENT OF PROBLEM. Despite an improved bone reactions of Mg-incorporated implants in the animals, little yet has been carried out by the experimental investigations in functional loading conditions. PURPOSE. This study investigated the clinical and histologic parameters of osseointegrated Mg-incorporated implants in early loading conditions. MATERIAL AND METHODS. A total of 36 solid screw implants(diameter 3.75 mm, length 10 mm) were placed in the mandibles of 6 beagle dogs. Test groups included 18 Mg-incorporated implants. Turned titanium implants served as control. Gold crowns were inserted 4 weeks after implant placement and the dogs were immediately put on a food diet. Implants were observed for 10 weeks after loading. Radiographic assessments and stability tests were performed at the time of fixture installation, $2^{nd}$ stage surgery, 4 weeks after loading, and 10 weeks after loading. Histological observations and morphometrical measurements were also performed. RESULTS. Of 36 implants, 33 displayed no discernible mobility, corresponding to successful clinical function. There was no statistically significant difference between test implants and controls in marginal bone levels(P=.46) and RFA values. The mean BIC % in the Mg-implants was $54.5{\pm}8.4%$. The mean BIC % in the turned implant was $45.3{\pm}12.2%$. These differences between the Mg-implant and control implant were statistically significant(P=.005). CONCLUSIONS. The anodized, Mg-incorporated implant demonstrated significantly more bone-to-implant contact(BIC) in early loading conditions. CLINICAL IMPLICATIONS. The results of this study in beagle dogs suggest the possibility of achieving predictable stability of early loaded free-standing dental implants with Mg-incorporated surface.

의도적 재식술을 시행한 대구치의 단기간의 임상 평가 (Short-term clinical outcome of intentionally replanted posterior molars)

  • 최용훈
    • Restorative Dentistry and Endodontics
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    • 제36권1호
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    • pp.12-18
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    • 2011
  • 목적: 본 후향적 연구의 목적은 의도적 재식술로 치료한 상하악 대구치의 단기간의 치료 결과를 평가하고자 하는 것이다. 환자 및 방법: 본 연구의 대상은 해부학적인 접근의 어려움 및 두꺼운 피질골 또는 하치조 신경, 상악동등과의 근접으로 인해 통상적인 치근단 수술이 불가능하거나 환자가 거부하는 경우 의도적 재식술을 시행한 35개의 상하악 대구치를 대상으로 하였다. 증례들의 경과 관찰 기간은 1년에서 2년 4개월이었다. 성공률은 임상적 성공과 방사선학적 성공을 기준으로 평가하였다. 결과: 의도적 재식술 과정중 발치 실패가 1증례(3%), 치주 질환 및 염증성 흡수로 발치한 경우가 2증례(6%)였고 구강내에서 기능하고 있으나 약간의 동요도와 치근의 흡수상이 관찰되는 경우가 3증례(9%)였고 특이한 이상없이 잘 유지되고 있는 경우는 29증례(82%)였다. 결론: 의도적 재식술은 접근성 및 해부학적인 구조등으로 인해 치근단 수술이 불가능한 경우 적절한 증례 선택과 숙련된 술자에 의해 시술이 이루어진다면 재현성 있고 예지성있는 치료가 될 수 있다.