• International journal of advanced smart convergence
• /
• 제13권1호
• /
• pp.37-47
• /
• 2024

This study presents the results of designing a system that determines the location of a person in an indoor environment based on a single IMU sensor attached to the tip of a person's shoe in an area where GPS signals are inaccessible. By adjusting for human footfall, it is possible to accurately determine human location and trajectory by correcting errors originating from the Inertial Measurement Unit (IMU) combined with advanced machine learning algorithms. Although there are various techniques to identify stepping, our study successfully recognized stepping with 98.7% accuracy using an artificial intelligence model known as Long Short-Term Memory (LSTM). Drawing upon the enhancements in our methodology, this article demonstrates a novel technique for generating a 200-meter trajectory, achieving a level of precision marked by a 2.1% error margin. Indoor pedestrian navigation systems, relying on inertial measurement units attached to the feet, have shown encouraging outcomes.

• 대한치과교정학회지
• /
• 제41권5호
• /
• pp.354-360
• /
• 2011

Objective: To investigate the effects of different pilot-drilling methods on the biomechanical stability of self-tapping mini-implant systems at the time of placement in and removal from artificial bone blocks. Methods: Two types of artificial bone blocks (2-mm and 4-mm, 102-pounds per cubic foot [102-PCF] polyurethane foam layered over 100-mm, 40-PCF polyurethane foam) were custom-fabricated. Eight mini-implants were placed using the conventional motor-driven pilot-drilling method and another 8 mini-implants were placed using a novel manual pilot-drilling method (using a manual drill) within each of the 2-mm and 4-mm layered blocks. The maximum torque values at insertion and removal of the mini-implants were measured, and the total energy was calculated. The data were statistically analyzed using linear regression analysis. Results: The maximum insertion torque was similar regardless of block thickness or pilot-drilling method. Regardless of the pilot-drilling method, the maximum removal torque for the 4-mm block was statistically higher than that for the 2-mm block. For a given block, the total energy at both insertion and removal of the mini-implant for the manual pilot-drilling method were statistically higher than those for the motor-driven pilot-drilling method. Further, the total energies at removal for the 2-mm block was higher than that for the 4-mm block, but the energies at insertion were not influenced by the type of bone blocks. Conclusions: During the insertion and removal of mini-implants in artificial bone blocks, the effect of the manual pilot-drilling method on energy usage was similar to that of the conventional, motor-driven pilot-drilling method.

• BMB Reports
• /
• 제39권4호
• /
• pp.339-345
• /
• 2006

The blood-neural barrier (BNB), including blood-brain barrier (BBB) and blood-retinal barrier (BRB), is an endothelial barrier constructed by an extensive network of endothelial cells, astrocytes and neurons to form functional 'neurovascular units', which has an important role in maintaining a precisely regulated microenvironment for reliable neuronal activity. Although failure of the BNB may be a precipitating event or a consequence, the breakdown of BNB is closely related with the development and progression of CNS diseases. Therefore, BNB is most essential in the regulation of microenvironment of the CNS. The BNB is a selective diffusion barrier characterized by tight junctions between endothelial cells, lack of fenestrations, and specific BNB transporters. The BNB have been shown to be astrocyte dependent, for it is formed by the CNS capillary endothelial cells, surrounded by astrocytic end-foot processes. Given the anatomical associations with endothelial cells, it could be supposed that astrocytes play a role in the development, maintenance, and breakdown of the BNB. Therefore, astrocytes-endothelial cells interaction influences the BNB in both physiological and pathological conditions. If we better understand mutual interactions between astrocytes and endothelial cells, in the near future, we could provide a critical solution to the BNB problems and create new opportunities for future success of treating CNS diseases. Here, we focused astrocyte-endothelial cell interaction in the formation and function of the BNB.

• Archives of Plastic Surgery
• /
• 제34권5호
• /
• pp.593-598
• /
• 2007

Purpose: Talipes equinus deformity is defined as impossibility of heel weight-bearing and lacking of improvement of toe-tip gait despite sufficient duration of conservative treatment. The incidence of equinus deformity induces post-traumatic extensive soft tissue defect and subsequently increases it. Severe equinus deformities of the foot associated with extensive scarring of the leg and ankle were corrected using achilles Z-lengthening and free-tissue transfer. Methods: Free radial forearm flap was done in nine cases of eight patients from January 2000 to November 2006. Causes of deformity were post-traumatic contracture (one patient) and post-burn scar contracture (seven patients). Seven patients were male, one patient was female. Mean age was 32.1 (range, 10-57). Flap donors were covered with artificial dermis ($Terudermis^{(R)}$) and split thickness skin graft (five cases), and medium thickness skin graft only (four cases). Results: The size of flaps varied from $6{\times}12$ to $15{\times}12cm$ (average, $12{\times}7.8cm$). Achilles tendon was lengthened 4.2cm on average. Free radial forearm flap was satisfactory in all cases. All patients could ambulate normally after the surgery. Cases having donor coverage with $Terudermis^{(R)}$ were aesthetically better than those having skin grafts only. Conclusion: This study suggested that severe equinus deformities associated with extensive scarring of the leg and ankle can be corrected effectively free radial forearm flap and Achilles tendon lengthening.

• 한국의류학회지
• /
• 제35권1호
• /
• pp.1-12
• /
• 2011

This study tests the performance of the recommended winter dress OnMapsi for an office worker through the analysis of skin temperature changes according to the heating environment. We tested and compared the effects of with/without undergarments for 4 male subjects in an artificial-climate chamber with two air temperatures of $19^{\circ}C$ and $22^{\circ}C$, $50{\pm}10%$ R.H. During the 60 minute experiment that simulated office work, the subjective feelings (that included thermal, humidity and comfort sensation, and skin temperature) were measured at equal intervals. The results show that the forehead and chest skin temperatures were not affected by air temperature or clothing type, while the hand and foot skin temperatures were affected at $0.3-0.9^{\circ}C$ depending on clothing type and $1.9-2.2^{\circ}C$ depending on air temperature. The mean skin temperature was decreased by the experimental time pass more with regular formal wear than with OnMapsi. The second experiment located the ambient temperature in which subjects wearing OnMapsi show equal skin temperaturesto those without undergarments at $22^{\circ}C$. Therefore it is possible to decrease heating temperatures to $18-21^{\circ}C$ in the office for winter OnMapsi wear that produces a skin temperature and thermal sensation that is the same as those at $22^{\circ}C$.

• 제어로봇시스템학회논문지
• /
• 제22권3호
• /
• pp.199-203
• /
• 2016

A brain-computer interface or BCI provides an alternative method for acting on the world. Brain signals can be recorded from the electrical activity along the scalp using an electrode cap. By analyzing the EEG, it is possible to determine whether a person is thinking about his/her hand or foot movement and this information can be transferred to a machine and then translated into commands. However, we do not know which information relates to motor imagery and which channel is good for extracting features. A general approach is to use all electronic channels to analyze the EEG signals, but this causes many problems, such as overfitting and problems removing noisy and artificial signals. To overcome these problems, in this paper we used a new optimization method called the Fruit Fly optimization algorithm (FOA) to select the best channels and then combine them with CSP method to extract features to improve the classification accuracy by linear discriminant analysis. We also used particle swarm optimization (PSO) and a genetic algorithm (GA) to select the optimal EEG channel and compared the performance with that of the FOA algorithm. The results show that for some subjects, the FOA algorithm is a better method for selecting the optimal EEG channel in a short time.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2011년도 제40회 동계학술대회 초록집
• /
• pp.449-449
• /
• 2011

We reported the direct effect of intrinsic surface energy of dry adhesive material to the Van der Waals and capillary forces contributions of the total adhesion force in an artificial gecko-inspired adhesion system. To mimic the gecko foot we fabricated tilted nanohairy structures using both lithography and ion beam treatment. The nanohairy structures were replicated from Si wafer mold using UV curable polymeric materials. The control of nanohairs slanting angles was based on the uniform linear argon ion irradiation to the nanohairy polymeric surface. The surface energy was studied utilizing subsequent conventional oxygen ion treatment on the nanohairy structures which resulted in gradient surface energy. Our shear adhesion test results were found in good agreement with the accepted Van der Waals and capillary forces theory in the gecko adhesion system. Surface energy would give a direct impact to the effective Hamaker constant in Van der Waals force and the filling angle (${\varphi}$) of water meniscus in capillary force contributions of gecko inspired adhesion system. With the increasing surface energy, the effective Hamaker constant also increased but the filling angle decreased, resulting in a competition between the two forces. Using a simple mathematical model, we compared our experimental results to show the quantitative contributions of Van der Waals and capillary forces in a single adhesion system on both hydrophobic and hydrophilic surfaces. We found that the Van der Waals force contributes about 82.75% and 89.97% to the total adhesion force on hydrophilic and hydrophobic test surfaces, respectively, while the remaining contribution was occupied by capillary force. We also showed that it is possible to design ultrahigh dry adhesive with adhesion strength of more than 10 times higher than apparent gecko adhesion force by controlling the surface energy and the slanting angle induced-contact line of dry adhesive the materials.

• 한국패류학회지
• /
• 제31권2호
• /
• pp.103-112
• /
• 2015

해만가리비는 남해 해역에서 양식이 되고 있는 품종이다. 국립수산과학원은 동해 남부 해역에서 해만가리비 양식기술을 개발하고자 하였다. 산란 유도를 위해 간출자극과 $23^{\circ}C$로 조정된 수온자극을 실시하였다. 해만가리비의 산란량은 총 105,58 만 개 이였다. 수정률은 91.3%로 9,394 만 개가 수정되었다. 수정란은 원형으로 $54.1{\pm}0.04-67.4{\pm}0.12{\mu}m$로 평균 직경이 $61.7{\pm}0.05{\mu}m$이였다. 약 5일 후에는 초기원각 (prodissoconch shell) 을 형성하여 각정기 유생기 (umbo stage larva) 가 시작되며 각정 (umbones) 이 형성되었다. 약 8일후에는 $150.4-204.8{\mu}m$ (평균 $179.7{\pm}8.4{\mu}m$) 크기의 부유유생이 되어 섬모가 있고 발 (foot) 과 안점 (eye spot) 이 생성되었다. 수정 후 10일 후에는 평균 각장 $235.4{\pm}9.7{\mu}m$ 로 성장 하였으며 팜사나 경심망 등의 기질에 부착하여 부착치 패가 되었다. 치패 각장 성장은 22.71 mm 이였으며, 8월에 47.19 mm, 10월에 60.43 mm, 12월 72.40 mm 로 성장하였다. 전중량은 6월 이식 당시에는 2.0 g 이였으나 10월에 32.7 g으로 증가하였으며 12월에는 46.6 g 으로 증가하였다. 해만가리비의 일간 성장률은 각장의 경우, 4-6월이 0.35 mm/day, 6-8월 0.41 mm/day로 큰 폭으로 성장하였다.

• Journal of Plant Biotechnology
• /
• 제31권4호
• /
• pp.285-293
• /
• 2004

FMDV는 동물에서 구제역을 일으키는 병원체이며, VP1은 이 바이러스의 주요 capsid단백질이므로 구제역의 진단과 단백질 백신의 개발에 가장 많이 사용되는 재료 중 하나이다. 본 연구는 FMDV taiwan O형과 베트남에서 분리된 FMDV의 VP1 sequence를 기반으로 식물에서 VP1 유전자의 발현을 위하여 633 bp의 VP1유전자로 재편집하였으며, 이를 long-nucleotide를 사용한 multiple fragment extension 방법을 사용하여 인공적인 DNA 단편을 합성하였다. 또한 새로운 식물 형질전환 벡터로 pBI121 과 pCAMBIA1390의 장점을 수용하여, hygromycin 저항성과 CaMV 35S promoter를 포함하는 pCAMBIA II를 제작하였다. 제작된 벡터와 VP1 유전자 및 GFP유전자를 사용하여 담배를 형질 전환시켰고, 각각의 형질전환식물체내에서 전체길이의 target gene(VPl)의 성공적인 삽입을 확인하였다. 각 유전자의 발현은 RT-PCR과 Real-Time PCR의 결과로 측정하였으며, VP1 유전자의 전사가 담배 내에서 이루어졌음과 고효율의 전사체를 만드는 형질전환체 VP1-4를 선별하였다.

• 한국잠사곤충학회지
• /
• 제50권2호
• /
• pp.133-139
• /
• 2012

본 연구는 남방노랑나비의 인공사육을 위한 서식지의 생태환경조사와 실내에서의 인공사육조건을 구명하기 위해 수행되었다. 서식지의 생태환경조사를 위해 남방노랑나비의 주 서식지인 경남 사천시 곤양면 대진리(A지역, 하천변의 개활지)와 남해군 설천면 노량리(B지역, 구릉성 산자락) 두 곳을 조사지로 선정하여, 2010년 6월부터 2010년 11월까지 6개월간 월 2회 정기적으로 조사하였다. 조사결과, 산자락인 B지역의 남방노랑나비의 개체수가 개활지인 A지역보다 성충의 경우 6배 더 많은 것으로 나타났다. 또한 알, 애벌레, 번데기도 더 많은 수가 조사되었다. B지역의 경우 먹이식물이 다양하게 분포하였으며, 먹이식물의 선호도는 비수리에서 170개체가 관찰되어 자연에서는 비수리가 가장 선호하는 기주식물임이 확인되었다. 실내 사육조건을 구명하기 위해 남방노랑나비의 실내 사육을 실험하였다. 기주식물에 따른 산란선호도를 조사하기위해 암 수 100개체를 산란장에 넣고 짝짓기를 유도한 후 비수리와 결명자를 넣고 10분간 산란한 알의 수를 세어 산란선호도를 조사한 결과 비수리에 산란한 알의 수가 $104.9{\pm}19.6$개로 결명자의 $12.7{\pm}4.5$개 보다 많아 비수리의 산란선호도가 높게 나타났다. 산란된 알을 고온 장일 조건($25^{\circ}C$, 16L : 8D)의 인공적인 환경에서 사육한 결과, 산란된 알의 부화율은 53.7%이었으며, 산란에서 부화까지 평균 소요일수는 $5.1{\pm}0.9$일이었다. 유충기간은 $12.1{\pm}0.9$일이었으며, 각 령별 두폭측정 결과 1령 $0.36{\pm}0.02$, 1령 $0.61{\pm}0.02$, 3령 $0.93{\pm}0.05$, 4령 $1.46{\pm}0.08$, 5령 $2.25{\pm}0.11$로 나타났다. 사육된 애벌레의 용화율은 81.0%으로 나타났으며, 번데기기간은 평균 $6.9{\pm}0.7$일로 조사되었다. 나비의 우화율은 79.6%으로 나타났다. 이상의 실험결과 남방노랑나비의 자연상태에서의 서식환경과 실내 인공사육을 위한 사육조건이 확인되었다.