Earticle

In this study, the calorimeter was used to experimentally investigate the heating characteristics of the variable A/C system according to changes in loading time and outdoor dry bulb temperature. The heating capacity, COP and compressor discharge temperature were measured while changing the loading time of the compressor. To develop the correlation for compressor discharge temperature, loading time, indoor dry bulb temperature and outdoor dry bulb temperatures were considered as operating variables. As the outdoor temperature and loading time increased, the heating capacity and COP increased. However, the change in COP showed different trends depending on the outdoor temperature. The evaporation temperature according to the loading time is a good estimate of the outdoor temperature. However, as the temperature difference between indoor and outdoor rooms decreases and the loading time increases, the condensation pressure increases significantly, so the condensation temperature increases. The maximum deviation between the correlation and the experimental value for compressor discharge temperature was within approximately 2℃.

Objectives: The objective of this study is compare the rate of marginal bone resorption around hydroxyapatite-coated implants given different loading times in order to evaluate their stability. Materials and Methods: The study was conducted retrospectively for one year, targeting 41 patients whose treatment areas were the posterior maxilla and the mandible. Osstem TS III HA (Osstem Implant Co., Busan, Korea) and Zimmer TSV-HA (Zimmer Dental, Carlsbad, CA, USA), which employ the new hydroxyapatite coating technique, were used. The patients were divided into two groups - immediate and delayed loading - and the bone level at the time of loading commencement and after one year of loading was measured using periapical radiography. Differences between the groups were evaluated using Mann-Whitney (${\alpha}$=0.05). Results: For all patients as a single group, the survival rate of the implants was 100%, and the mean marginal bone loss was $0.26{\pm}0.59mm$. In comparison of the differences by loading, mean marginal bone loss of $0.32{\pm}0.69mm$ was recorded for the immediate loading group whereas the delayed loading group had mean marginal bone loss of $0.16{\pm}0.42mm$. However, the difference was not significant (P>0.05). Conclusion: Within the limited observation period of one year, predictable survival rates can be expected when using immediately loaded hydroxyapatite-coated implants.

PURPOSE. The purpose of this prospective study was to evaluate the effect of early loading on survival rate or clinical parameter of anodic oxidized implants during the 12- month postloading period. MATERIALS AND METHODS. Total 69 implants were placed in 42 patients. Anodic oxidized implants (GS II, Osstem Cor., Busan, Korea) placed on the posterior mandibles were divided into two groups, according to their prosthetic loading times: test group (2 to 6 weeks), and control group (3 to 4 months). The implant survival rates were determined during oneyear postloading period and analyzed by Kaplan-Meier method. The radiographic peri-implant bone loss and periodontal parameters were also evaluated and statistically analyzed by unpaired t-test. RESULTS. Total 69 implants were placed in 42 patients. The cumulative postloading implant survival rates were 88.89% in test group, compared to 100% in control group (P<.05). Periimplant marginal bone loss (T: $0.27{\pm}0.54$ mm, C: $0.40{\pm}0.55$ mm) and periodontal parameters showed no significant difference between the groups (P>.05). CONCLUSION. Within the limitation of the present study, implant survival was affected by early loading on the anodic oxidized implants placed on posterior mandibles during one-year follow-up. Early implant loading did not influence peri-implant marginal bone loss, and periodontal parameters.

Objectives: The objective of this study is compare the rate of marginal bone resorption around hydroxyapatite-coated implants given different loading times in order to evaluate their stability. Materials and Methods: The study was conducted retrospectively for one year, targeting 41 patients whose treatment areas were the posterior maxilla and the mandible. Osstem TS III HA (Osstem Implant Co., Busan, Korea) and Zimmer TSV-HA (Zimmer Dental, Carlsbad, CA, USA), which employ the new hydroxyapatite coating technique, were used. The patients were divided into two groups - immediate and delayed loading - and the bone level at the time of loading commencement and after one year of loading was measured using periapical radiography. Differences between the groups were evaluated using Mann-Whitney (α=0.05). Results: For all patients as a single group, the survival rate of the implants was 100%, and the mean marginal bone loss was 0.26±0.59 mm. In comparison of the differences by loading, mean marginal bone loss of 0.32±0.69 mm was recorded for the immediate loading group whereas the delayed loading group had mean marginal bone loss of 0.16±0.42 mm. However, the difference was not significant (P>0.05). Conclusion: Within the limited observation period of one year, predictable survival rates can be expected when using immediately loaded hydroxyapatite-coated implants.

STATEMENT OF PROBLEM: The application of a simple, clinically applicable noninvasive test to assess implant stability are considered highly desirable. So far there is still a controversy about correlation of various tests and implant stability. PURPOSE: In order to assess implant stability, the development of a new method is critical. It's possible to assess implant stability by calculating energy and angular momentum during implant installation. The purpose of this study is to evaluate the correlation of energy and implant stability. MATERIAL AND METHODS: Twenty three implants were installed in two different types of pig bone. Type I bone was retrieved from the distal aspect of the rib, with more cortical bone. Type II bone came from a more proximal region with less cortical components and a higher content of bone marrow and spongeous trabeculae. Insertion torque, removal torque, ISQ values and angular momentum and energy were measured. Pearson Correlation test was done to analyze the relation between RFA, maximum insertion torque, mean insertion torque, bone type, energy and removal torque. RESULTS: Type I bone showed higher removal torque than type II bone. Energy value was significantly correlated with maximum insertion torque and mean insertion torque. RFA values were related with insertion torques but the significance was lower than Energy value. CONCLUSION: Within the limitation of this study energy values were considered clinically predictable method to measure the implant stability.

A laboratory-scale dual-column biofilter system was used to study the biofiltration of dimethyl disulfide(DMDS). The biofiltration of DMDS was found to depend on the pollutant loadings rather than the inlet concentrations. It was estimated that the pollutant was only inhibitory to the operation of the biofilters at DMDS concentrations greater than 5500 ppmv A residence time of 30 seconds(120 m$^3$/m$^2$/h volumetric loading) was determined as appropriate for efficient operation(>90%). The maximum elimination capacity for both compost mixtures under the current experimental conditions was found to range from 7.5 to 10 g-DMDS/m$^3$/h. A lower DMDS maximum elimination capacity was exhibited under acidified conditions.

Objectives: This study was performed to evaluate patterns of failure time after insertion, failure rate according to loading time after insertion, and the patterns of failure after loading. Materials and Methods: A total of 331 mini-implants were classified into the non-failure group (NFG) and failure group (FG), which was divided into failed group before loading (FGB) and failed group after loading (FGA). Orthodontic force was applied to both the NFG and FGA. Failed mini-implants after insertion, ratio of FGA to NFG according to loading time after insertion, and failed mini-implants according to failed time after loading were analyzed. Results: Percentages of failed mini-implants after insertion were 15.79%, 36.84%, 12.28%, and 10.53% at 4, 8, 12, and 16 weeks, respectively. Mini-implant failure demonstrated a peak from 4 to 5 weeks after insertion. The failure rates according to loading time after insertion were 13.56%, 8.97%, 11.32%, and 5.00% at 4, 8, 12, and 16 weeks, respectively. Percentages of failed mini-implants after loading were 13.79%, 24.14%, 20.69%, and 6.9% at 4, 8, 12, and 16 weeks, respectively. Conclusion: Mini-implant stability is typically acquired 12 to 16 weeks after insertion, and immediate loading can cause failure of the mini-implant. Failure after loading was observed during the first 12 weeks.

Objectives: This study was performed to evaluate patterns of failure time after insertion, failure rate according to loading time after insertion, and the patterns of failure after loading.Materials and Methods: A total of 331 mini-implants were classifiedinto the non-failure group (NFG) and failure group (FG), which was divided into failed group before loading (FGB) and failed group after loading (FGA). Orthodontic force was applied to both the NFG and FGA. Failed mini-implants after insertion, ratio of FGA to NFG according to loading time after insertion, and failed mini-implants according to failed time after loading were analyzed.Results: Percentages of failed mini-implants after insertion were 15.79%, 36.84%, 12.28%, and 10.53% at 4, 8, 12, and 16 weeks, respectively. Mini-implant failure demonstrated a peak from 4 to 5 weeks after insertion. The failure rates according to loading time after insertion were 13.56%, 8.97%, 11.32%, and 5.00% at 4, 8, 12, and 16 weeks, respectively. Percentages of failed mini-implants after loading were 13.79%, 24.14%, 20.69%, and 6.9% at 4, 8, 12, and 16 weeks, respectively.Conclusion: Mini-implant stability is typically acquired 12 to 16 weeks after insertion, and immediate loading can cause failure of the mini-implant. Failure after loading was observed during the first 12 weeks.

Influences of hold time and stress ratio on cyclic creep properties of Grade 91 steel were systemically investigated using a wide range of cyclic creep tests, which were performed with hold times (HTs) of 1 minute, 3 minutes, 5 minutes, 10 minutes, 20 minutes, and 30 minutes and stress ratios (R) of 0.5, 0.8, 0.85, 0.90, and 0.95 under tension loading cycles at $600^{\circ}C$. Under the influence of HT, the rupture time increased to HT = 5 minutes at R = 0.90 and R = 0.95, but there was no influence at R = 0.50, 0.80, and 0.85. The creep rate was constant regardless of an increase in the HT, except for the case of HT = 5 minutes at R = 0.90 and R = 0.95. Under the influence of stress ratio, the rupture time increased with an increase in the stress ratio, but the creep rate decreased. The cyclic creep led to a reduction in the rupture time and an acceleration in the creep rate compared with the case of monotonic creep. Cyclic creep was found to depend dominantly on the stress ratio rather than on the HT. Fracture surfaces displayed transgranular fractures resulting from microvoid coalescence, and the amount of microvoids increased with an increase in the stress ratio. Enhanced coarsening of the precipitates in the cyclic creep test specimens was found under all conditions.

대용량의 연속 매체(continuous media)를 서비스하기 위한 멀티미디어 저장 서버는 실시간 검색과 대용량의 저장 장치 요구를 만족해야 한다. 그러나 기존에 연구되고 있는 디스크 배열(disk array)을 이용한 저장 서버는 성능 면에서 멀티미디어 응용에 바람직한 면이 있지만, 대규모 서버를 위한 저장 장치 전체를 디스크로 구성하는 것은 비용 면에서 비현실적일 뿐만 아니라 저장 용량과 대역폭에도 한계가 있다. 따라서 본 논문은 저가의 대용량 DVD-ROM을 사용한 계층적 저장 서버에서 파이프라인 로딩 기법을 제안한다. 제안된 기법은 시뮬레이션 성능분석을 통하여 파이프라인 상황하최대 허용 스트림 수가 크게 증가될 수 있음을 보인다.

This paper provides a real-time loading strategy for batch processing machines in which a number of jobs are simultaneously processed as a batch. The batch processing machines can be seen in both manufacturing industries (e.g., semiconductor, automobile and metal working) and service industries (transportation vehicles, mail shipment and theme park). This paper focuses on batch processing machines in semiconductor manufacturing. We present a look-ahead loading strategy for tardiness minimization where future arrivals and due dates are taken into consideration. Simulation tests are performed on the presented strategy and some existing loading heuristics under various production settings with different traffic intensities and forecasting errors. Experimental results show that our strategy provides the performance of good quality.

The purpose of this study is to suggest a fundamental data for change of dynamic properties according to the loading time of resilient materials. 18 kinds of resilient materials included 4 representative types were measured at the load time of 24hours and 2hours by the method of Korea standard (KS F 2868) measuring the dynamic stiffness and the loss factor of materials under floating floors. As a result, the dynamic stiffness was increased rapidly in case of expandable polystyrene and rubber materials according to the load time, especially before 2 hours. The loss factor was represented that rubber materials with high elasticity are high, and expandable polystyrene, polyester, poly ethylene materials with low elasticity are low.

We fabricated fiber gratings with three different Ge-doped fibers exposed to 60atm pressure of Hz gas at 90"C for different times and studied the effects of Ge-doping concentration and $H_2$ loading time on the growth of gratings. According to experiments. the growing effect of hydrogen loading on high Ge-doped fiber was great.

현재 다양한 성격을 가진, 무수히 많은 웹사이트들이 존재하고 있다. 웹사이트에 접속시 또는 이벤트 실행 시 걸리는 로딩 시간은 사이트를 이용하는 사용자로 하여금 서비스의 질 문제를 야기시킬 수 있으며 나아가서는 비즈니스에서 큰 영향을 미칠 수 있다. 이러한 이유 등으로 브라우저들의 성능은 점점 좋아지고 있으며, 복잡해지는 프론트엔드 로직에 따라 다양한 환경에서의 빠른 개발 및 웹 페이지 성능 개선을 위한 각종 Javascript 프론트엔드 프레임워크들도 등장하고 있다. 비동기 통신 방법인 Ajax 기술을 사용하는 프레임워크를 통해 렌더링 처리 방안을 확인해보고, 속도 성능에 대한 비교 분석을 한다.

현재 다양한 성격을 가진, 무수히 많은 웹사이트들이 존재하고 있다. 웹사이트에 접속시 또는 이벤트 실행 시 걸리는 로딩 시간은 사이트를 이용하는 사용자로 하여금 서비스의 질 문제를 야기시킬 수 있으며 나아가서는 비즈니스에서 큰 영향을 미칠 수 있다. 이러한 이유 등으로 브라우저들의 성능은 점점 좋아지고 있으며, 복잡해지는 프론트엔드 로직에 따라 다양한 환경에서의 빠른 개발 및 웹 페이지 성능 개선을 위한 각종 Javascript 프론트엔드 프레임워크들도 등장하고 있다. 비동기 통신 방법인 Ajax 기술을 사용하는 프레임워크를 통해 렌더링 처리 방안을 확인해보고, 속도 성능에 대한 비교 분석을 한다.

GPU를 이용한 병렬 알고리즘은 어떤 메모리를 사용하는지에 따라 시스템의 전체적인 성능이 달라진다. 본 논문은 GPU 환경에서 실행되는 CUDA 프레임워크에서 병렬처리를 이용하여 문서 분류 시스템의 속도를 향상시키고자 할 때 메모리 로딩 시간이 전체적인 시스템의 성능에 미치는 영항을 연구하였다. 기존의 CPU 환경에서 구현했을 때와 비교하여 어느 정도의 성능 향상이 있었는지 실험하였으며 이전 연구에서 고려하지 않았던 메모리를 읽는데 걸리는 시간을 고려하여 현실적인 실행 시간을 비교하였다. 실험 결과에 의하면 CPU 에서 구현했을 때의 연산 속도보다 GPU의 텍스쳐 메모리를 사용하여 구현하였을 때 문서분류 성능이 향상되는 효과가 있음을 알 수 있었다.