• 대한치과보철학회지
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• 제39권4호
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• pp.391-409
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• 2001

Since the early study about the osseointegration, lots of researches have been performed to increase the success rate and the stress around the implant in the jaw bone has been considered as one of the causes of failure. The purpose of this study was to examine the relationship between the implant failure and the stress by analysing the influence of different bone quality and bite force of some foods on the stress distribution around the implant, and to estimate the treatment result according to the bone quality and dietary pattern of patients. Bone quality was divided in 4 groups and models were drawn with the assumption that thread type implant(Nobel Biocare AB, Goteborg, Sweden) of 3.75mm diameter, 13mm length was installed to the bones. Various bite forces were applied to the occlusal surface of superstructure and the stress distributed around the implant were analysed with finite element analysis program. The results were as follows ; 1. The stress was changed proportionally to the bite forces of foods at all measuring points in all load cases. 2. The stress at the marginal bone was higher than that of the other measuring points in all load cases, and it was decreased at the first thread area. 3. The stress at the marginal bone was highest in type IV bone in all load cases. Especially it was twice those of other bone types at the bucco-lingual marginal bone and 50% higher at the mesio-distal marginal bone. 4. The stress at the bucco-lingual sides of the bone around the apical portions of implant showed little differences among the bone types, while type IV bone showed lower stress concentration than the other bone types in the mesio-distal sides. 5. Under the buccal oblique load ($15^{\circ}$ ), the stress at the lingual marginal bone was higher than that of buccal marginal bone, and the difference between the two points was almost same regardless of bone types.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 춘계 종합학술대회 논문집
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• pp.422-428
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• 2005

본 논문에서는 멀티미디어 콘텐츠의 프리젠테이션 품질을 유지하기 위해 멀티미디어 콘텐츠를 처리할 때 발생하는 여러 사건들을 이벤트(event)로 정의하고, 각각의 특징에 따라 여러개의 클래스로 분류하였다. 그리고 이벤트의 처리와 관리에 의해 프리젠테이션 동기화를 처리할 수 있는 모델을 제안하였다. 또한, 쇼(show) 진행에 관련된 실행모듈, 스레드(thread) 등이 이벤트를 이용하여 상호 통신함으로써 프리젠테이션 서비스를 유지하는 방안에 대해 제안하였다. 특히, 제안된 모델에서는 사용자 인터페이스를 통해 사용자가 프리젠테이션 수행에 직접적으로 개입할 수 있을 뿐만 아니라 서비스 과정에서 발생하는 예측 불가능한 상태 변화에 대하여 능동적으로 대처함으로써 멀티미디어 문서의 프리젠테이션 품질을 유지할 수 있도록 하였다.

• 대한치과보철학회지
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• 제41권2호
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• pp.169-181
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• 2003

Statement of problem : The survival rate of wide diameter implants was lower than of 3.75-mm implants in some clinical researches. Purpose : The purpose of this study was to investigate the influence of implant diameter on the osseointegration of implants in the rabbit femoral condyle and tibial metaphyses by means of removal torque measurements and histomorphometric analysis. Material and Method : Ten adult New Zealand White rabbits were used in this study Two 3.75-mm diameter implants were inserted through one cortical layer in the tibial metaphyses and one 3.75-mm diameter implant was inserted in the femoral condyle. 5.0-mm diameter implants were inserted in the other leg in the same manner. A total of 60 implants (3.75-mm diameter implants:30 : 5.0-mm diameter implants:30) were installed. After a healing time of 4 and 12 weeks, the peak removal torque values required to shear off the implants were recorded. From the removal torque values (Ncm) obtained, the mean shear stress ($N/mm^2$) was calculated. And the percentage of direct bone-to-implant contact and the percentage of bone area inside the thread were measured by Kappa Image Base-metreo. The Student's t-test was undertaken for statistical analysis (p<0.05). Results : The removal torque value of 5.0-mm diameter implants was higher than of 3.75-mm diameter implants (p<0.05). The difference of shear stress value between 3.75-mm and 5.0-mm diameter implants was not statistically significant (p>0.05). The percentage direct bone-to-implant contact had no statistical difference between two groups (p>0.05). The percentage of bone area inside the thread had no statistical difference between two groups (p>0.05). Conclusion It is concluded that the quality f osseointegration is not influenced by increasing implant diameter.

• 대한본초학회지
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• 제36권1호
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• pp.87-95
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• 2021

Objective : Liquidambaris Storax, the processed resin of Liquidambar orientalis Mill., has been therapeutically used as orifice-opening medicinals in Korean Medicine. However, unauthenticated resinous drugs from various origins were sold as Liquidambaris Storax. This study aimed to establish the quality assessment of genuine Liquidambaris Storax and to provide quantitative differences of Liquidambaris Storax in herbal markets. Methods : Bibliographic research on ancient Liquidambaris Storax was performed using classic books of herbology. The quality assessment was approached by searching modern books of herbal medicines. The marker compounds in Liquidambaris Storax from various origins were quantitatively analyzed using high-performance liquid chromatography. Results : L. orientalis was botanically characterized by palmately 5-lobed shape of leaves. Genuine Liquidambaris Storax was recognized as resinous or semi-solid form (ancient―Song dynasty) to liquid form (Myeong/Cheong dynasty) and two processed forms were available in current markets. Genuine liquid Liquidambaris Storax should be lengthened as a thread when it was lifted by a stick and be sunken under the water. The crystals of cinnamic acid was seen under microscopic observation and the scent of benzaldehyde occurred after the treatment with potassium permanganate. Cinnamyl alcohol, cinnamic acid, and cinnamaldehyde were quantified in two liquid samples of Liquidambaris Storax, while cinnamaldehyde was not quantified in resinous (semi-solid) sample. Conclusion : This study presents the detailed methods of quality assessment for genuine Liquidambaris Storax as well as the status in the herbal markets. Further quantitative study with diverse samples is required to establish the quality standard of Liquidambaris Storax.

• 한국기계가공학회지
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• 제10권1호
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• pp.80-86
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• 2011

This study compared and analyzed manual tapping and automatic tapping regarding tapping process characteristics of titanium hard-to-cut-material. Tapping process characteristics of titanium hard-to-cut-material are evaluated as the quality of a screw, wear of a tap, economic analysis, and cycle time etc. The type of screw threads after manual tapping is formed as an irregular type of screw threads, and perfect screw threads are created after automatic tapping. In addition, the chip type after manual tapping process is formed as the discontinuous chip due to work hardening, and the powder type of chip after automatic tapping process is created. In terms of cycle time, an automatic tapping process is shortened by 70% compared to manual tapping process. Insert tip wear of an automatic tapping shown in the process of 5-hole tapping is not found, but hand tap wear for finish cutting is most severe.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2007년도 학술대회
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• pp.350-353
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• 2007

This paper presents an real-time implementation of H.264/AVC High 4:4:4 Predictive profile decoder using general-purpose processors by exploiting multi-threading technique and Single Instruction Multiple Data (SIMD) instructions without any quality degradation. We analyze differences between the existing High profile and High 4:4:4 Predictive profile decoder, and show various optimization techniques to decode high fidelity and high definition (HD) video in real-time. Simulation results show that the proposed decoder can play high fidelity HD video at average 40 frames per seconds (fps) for the IBBrBP bistream and about 50 fps for the Intra-only bitstream.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.7-13
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• 2007

This study proposes a new screw measurement system that is capable of measuring the pitch or lead of a screw, which is one of the most important parameters representing the screw quality. There are various conventional methods for screw measurement including some mechanical and optical ones, but they can not be applied to measure the lead except the profiles or sizes. The newly suggested method is able to measure the pitch or lead directly. This is executed by scanning the thread with a digital probe while the target screw rotates. The devised measurement system is a integrated computer system which is composed of a stepping motor, a digital linear gauge and a chuck device for holding the measured screw. In order to operate the system effectively and conveniently, a computer program having graphical user interface facility is developed. Some experiments were done to prove the effectiveness of the system.

• 한국정보통신학회논문지
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• 제9권4호
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• pp.839-843
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• 2005

본 논문에서는 VHF 송수신기 셋트에 쉽게 장착할 수 있는 해상용 광대역 수신증폭기를 소형 경량, 저비용으로 제작하여 전반적인 수신기의 수신성능을 개선하고자 한다. 제작된 수신 증폭기는 140MHz $\~$ 170MHz 주파수 대역에서 3dBm 정도의 수신감도를 개선하는 특성을 나타내었다. 따라서 VHF대역을 이용하는 통신장비를 더욱 효율적으로 사용가능하며, 양질의 원거리통신이 가능하기 때문에 활용도가 매우 높을 것으로 사료된다.

• Journal of Acupuncture Research
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• 제40권2호
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• pp.129-134
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• 2023

In this review, we searched for clinical and experimental studies related to acupuncture-related therapy (ART) on the microbiome in musculoskeletal disorders (MSDs) through the electronic databases of MEDLINE via PubMed, EMBASE, and Oriental Medicine Advanced Searching Integrated System up to May 2023, without language restriction, and after the selection/exclusion process, the study design, target disease, intervention details, treatment period, outcomes, and study results were extracted. A total of 8 articles were selected. Two randomized controlled trials and 6 animal studies evaluated knee osteoarthritis, rheumatoid arthritis, spinal cord injury, ankylosing spondylitis, and osteoporosis. ART, including electroacupuncture, thread-embedding acupuncture, and moxibustion, affected microbiome modulation in MSDs. The results reveal that ART could be a potential treatment for regulating the microbiome in MSDs. However, further high-quality studies are needed.

• 한국산업융합학회 논문집
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• 제9권4호
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• pp.277-283
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• 2006

As the products such as HDD, Notebook, PDA, and Mobile Phone become smaller and thinner, the radius of threads as well as holes for assembling those products become smaller, even down to 1mm. To produce such small holes and thread efficiently, multi tapping is highly necessitated. However the multi tapping characteristics is not well known because its complicated cutting mechanism and thus the quality of the produced holes and threads is not well studied yet. In this paper, experiments have been conducted for small-radius threads using M2 and M2.6 and M3 cold forming tap to investigate multi tapping process using several useful signal such as torque and Z-axis encoder pulse. The surface and profile of the machined threads have been magnified and observed through a SEM.