• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.1
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• pp.111-116
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• 2010

To improve occupants' safety in an emergency, crashworthy design is necessary to rotorcraft design and development. Especially, landing gear has the important role for crashworthy design because landing gear absorbs relatively large energy for the crash landing. In addition, military specifications require failure of landing gear shall not increase danger to any occupants by penetration of the airframe. To meet the specification requirements, crashworthiness device like failure mechanism should be prepared so that landing gear is collapsed safely and doesn't penetrate the airframe. In this study, design and design development test of the failure mechanism which is necessary for the rotorcraft landing gear was performed. First, collapse scenario was determined for the landing gear not to penetrate the airframe. Then, the failure pin which is the most important part of the failure mechanism was designed with 2 strength range in order to meet design criteria. Finally, design of the failure mechanism was verified successfully by design development test.

• International Commerce and Information Review
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• v.13 no.3
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• pp.31-53
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• 2011

The purpose of this study is to find out the factors affecting the usage and performance of e-Trade in Chinese Small and Medium-sized Enterprises(SMEs). To achieve the purpose of the study, the research model and hypotheses, depicting the relationship among external factors, internal factors, relationship characteristics, e-Trade usage level, and performance were developed based on the existing literature on e-Trade. To test the significance of the research model and hypotheses, an empirical survey were conducted to the Chinese SMEs in Yangtze River Delta area, which are actively using the e-Trade in their trade processes. According to the result of the statistical analyses on the 85 effective questionnaires from the sample firms, support of the government related institutions(one of the external factors) and CEO's support(one of the internal factors) had significant relationship with e-Trade usage level, but no significant relationship was found between the relationship characteristics and e-Trade usage level. Like the results of the most of the existing literature, e-Trade usage level were formed to significantly affected the e-Trade performance. Finally, based on results of the empirical survey, several implications on the Chinese SME's e-Trade strategies and policy alternatives were proposed as a concluding remark.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.370-377
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• 1989

Jerusalem artichoke (Helianthus tuberosus L.) as a biomass potential crop has several distinct advantages such as vigorous growth on poor land and high yield of carbohydrate. In this crop, seed dormancy has hampered the efforts of seed-propagration and to use them in breeding programs for improving jerusalem artichoke. Several seed treatments were tested to determine their effectiveness in overcoming the seed dormancy found in five collected varietes of jerusalem artichoke. The first results showed that the seed fertilities of five collected varieties ranged from 2.4％ to 14.7％ and the number of seed produced by one plant ranged from 88 to 1058. Germinability of seeds stored for 3 months at room temperature after harvest was almost 0％ and it was not improved by addition to the treatments of temperature, light and GA3, while germinability of seeds stored for 27 months at room temperature after harvest increased to 47.5％ in germination rate. But the removal and pin-pricking of seedcoat were very effective in breaking the seed dormancy, giving germination of 96.8％ and 82.3％, respectively. These results showed that the seed dormancy of jerusalem artichoke was induced by the seedcoat. Besides the treatment of seedcoat removal and seedcoat-pinpricking, the treatment of low and wet stratification was also effective in breaking the seed dormancy of jerusalem artichoke. Whole dormant seeds incubated for 70 days in low and wet condition germinated over 85％.

• The KIPS Transactions:PartB
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• v.9B no.2
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• pp.245-254
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• 2002

IC package marking inspection system using machine vision locates and identifies the target elements from input image, and decides the quality of marking by comparing the extracted target elements with the standard patterns. This paper proposes an adaptive multi-level thresholding (AMLT) method which is suitable for a series of operations such as locating the target IC package, extracting the characters, and detecting the Pinl dimple. It also proposes a dynamic matching unit selection (DMUS) method which is robust to noises as well as effective to catch out the local marking errors. The main idea of the AMLT method is to restrict the inputs of Otsu's thresholding algorithm within a specified area and a partial range of gray values. Doing so, it can adapt to the specific domain. The DMUS method dynamically selects the matching unit according to the result of character extraction and layout analysis. Therefore, in spite of the various erroneous situation occurred in the process of character extraction and layout analysis, it can select minimal matching unit in any environment. In an experiment with 280 IC package images of eight types, the correct extracting rate of IC package and Pinl dimple was 100% and the correct decision rate of marking quality was 98.8%. This result shows that the proposed methods are effective to IC package marking inspection.

• Journal of the Korean Society of Radiology
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• v.10 no.5
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• pp.321-325
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• 2016

Dose creep is one of clinical errors that arises from the tester's inexperience or carelessness, and according to Task Group #116 of American Association of Physicists in Medicine, its continued occurrence is being reported in the digital method. At this point, the demand for an automatic exposure control device that minimizes the dose creep phenomenon and can improve reproducibility is increasing. In this study is to consider the automatic exposure control device sensor that can is not only easy to produce, but also reduce the dose creep phenomenon by conducting a research on high-efficient semiconductor sensor. As a result, the Intrinsic-type and PIN-type sensors have excellent optical property compared to Ref sensor, would have less shading effect, and have relatively low sensitivity, but would provide accurate feedback signals to automatic exposure control device with its consistent tendency according to exposure condition changes.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.3
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• pp.1187-1191
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• 2016

Background: The prevalence of prostate cancer (PCa) has been increasing in recent years. Treatment strategies are largely based on the results of bone scan screening. Therefore, our aim was to investigate predictors of positive bone metastasis in newly diagnosed PCa patients. Materials and Methods: After extensive review, 336 consecutive patients newly diagnosed with PCa between April 2010 and November 2013 at our institution were enlisted in the study. Patients were divided into two groups according to bone scan results. Univariate analyses (Chi-square test for discrete variables and independent t-test for continuous variables) were applied to determine the potentially significant risk factors associated with distant bone metastasis. Binary logistic regression analyses were used to further investigate the influence of these factors on bone metastasis. Results: The patient mean age was $71.9{\pm}8.6years$ (range: 48 to 94 years). The mean prostate specific antigen (PSA) level and biopsy Gleason score were $260.2{\pm}1107.8ng/mL$ and $7.4{\pm}1.5$, respectively. The body mass index (BMI) for the series was $24.5{\pm}3.4kg/m^2$. Sixty-four patients (19.0%) had a positive bone scan result. Patients with positive bone scan results had a significantly lower BMI ($23.3{\pm}3.5$ vs. $24.8{\pm}3.3$; p=0.003), a higher Gleason score ($8.5{\pm}1.1$ vs. $7.1{\pm}1.5$; p < 0.001), and a higher PSA level ($1071.3{\pm}2337.1$ vs. $69.4{\pm}235.5$; p < 0.001) than those without bone metastasis. Multivariate logistic regression analysis employing the above independent predictors demonstrated that a Gleason score of ${\geq}7$, clinical stage ${\geq}T3$, $BMI{\leq}22kg/m^2$, and an initial PSA level of ${\geq}20ng/mL$ were all independent predictors of bone metastasis. Conclusions: A bone scan might be necessary in newly diagnosed PCa patients with any of the following criteria: clinical stage T3 or higher, a Gleason score of 7 or higher, BMI equal to or less than 22, and a PSA level of 20 or higher.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7863-7867
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• 2014

Background: Retinoblastoma is a rare type of cancer that usually develops in early childhood. If left untreated it can cause blindness and even death. The aim of this study is to determine sociodemographic and clinical features of retinoblastoma patients and also to determine the treatment pattern and outcome in Malaysia. Materials and Methods: Data for this study were retrieved from the Retinoblastoma Registry of the National Eye Database (NED) in Malaysia. Hospital Kuala Lumpur, Hospital Umum Kuching, Sarawak and Hospital Queen Elizabeth, Kota Kinabalu were the major source data providers for this study. Data collected in the registry cover demography, clinical presentation, modes of treatment, outcomes and complications. Results: The study group consisted of 119 patients (162 eyes) diagnosed with retinoblastoma between 2004 and 2012. There were 68 male (57.1%) and 51 (42.9%) female. The median age at presentation was 22 months. A majority of patients were Malays (54.6%), followed by Chinese (18, 5%), Indians (8.4%), and indigenous races (15.9%). Seventy six (63.8%) patients had unilateral involvement whereas 43 patients had bilateral disease (36.1%). It was found that most children presented with leukocoria (110 patients), followed by strabismus (19), and protopsis (12). Among the 76 with unilateral involvement (76 eyes), enucleation was performed for a majority (79%). More than half of these patients had extraocular extension. Of the 40 who received chemotherapy, 95% were given drugs systemically. Furthermore, in 43 patients with bilateral involvement (86 eyes), 35 (41%) eyes were enucleated and 17 (49%) showed extraocular extension. Seventy-two percent of these patients received systemic chemotherapy. The patients were followed up 1 year after diagnosis, whereby 66 were found to be alive and 4 dead. Sixteen patients defaulted treatment and were lost to follow-up, whereas follow-up data were not available in 33 patients. Conclusions: Patients with retinoblastoma in this middle-income Asian setting are presenting at late stages. As a result, a high proportion of patients warrant aggressive management such as enucleation. We also showed that a high number of patients default follow-up. Therefore, reduction in refusal or delay to initial treatment, and follow-up should be emphasized in order to improve the survival rates of retinoblastoma in this part of the world.

• Journal of the Korean Arthroscopy Society
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• v.7 no.2
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• pp.183-188
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• 2003

Purpose : The purpose of this study is to evaluate the results of revision surgery for failed anterior cruciate ligament (ACL) reconstruction using quadruple hamstring tendon autograft. Materials and Methods : From May 2000 to July 2002, six patients received ACL revision surgery using quadruple hamstring autograft for failed ACL reconstruction. Femoral tunnels were made 40 mm in depth and fixed with a cross pin and a bioabsorbable interference screw to fill the bone defect. In tibial tunnels, the grafts were fixed with Intrafix(Mitek, Norwood, MA). In case of tibial tunnel widening, additional screw-washer fixation was done. Follow up was at least 12 months postoperatively. Clinical assessments consisted of Lysholm knee scores, International Knee Documentation Committee(IKDC) evaluation form and manual maximal side to side difference using KT-2000 arthrometer. Results : The average Lysholm knee score improved from 77.2 preoperatively to 87.7 postoperatively. At the final IKDC evaluation, 1 case was graded as normal, 4 nearly normal, 1 abnormal. Mean side to side difference of manual maximum anterior displacement using the KT-2000 arthrometer was 1.8mm. The success rate was $83\%$. Conclusion : ACL revision surgery using quadruple hamstring autograft with double fixation is considered good procedure with successful results.

• The Korean Journal of Mycology
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• v.26 no.4 s.87
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• pp.531-537
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• 1998

Forest green mold incidence rate, extent of damage according to the inoculation periods, and its cultural characteristics were observed in the automatic cultural system of the winter mushroom, Flammulina velutipes. The incidence rate of the forest green mold was 7.7% in early cultivation stage and slowly increased to 14.9% in harvest stage. When the forest green mold was inoculated at cultural period, the rate was recorded at 100%, but the extent of the damage increased up to 40% (+++). There was also 100% incidence rate at early pinheading time, whereas the yield of mushroom decreased to ++ $(10{\sim}39%)$. The rate of forest green mold was greatly decreased to 34.4% at 10 days after pinheading, and its damage extent was also below 10%. A pathogen to infect the winter mushroom was identified as Trichoderma pseudokoningii. It's optimum temperature for mycelial growth is $25^{\circ}C$, and it grew 2.6 times faster than that of F. velutipes. The mycelial color of T. pseudokoningii was pale yellow or olivaceous in shades on PDA medium. Phialospore was one celled, and ellipsodal or obovoid, smooth walled, and measured $1.3{\sim}3.0{\times}1.0{\sim}2.5\;{\mu}m$. It aggregated in small heads at the tips of the phialides. The phialides were $3.2{\sim}9.2{\times}2.0{\sim}5.5\;{\mu}m$ and were of bowling pin type, solitary and alternate or more irregularly disposed at the conidiophore apex, T. pseudokoningii depressed the F. velutipes growth at the crossing cultivation when they were simultaneously. FV 4-1 (F. velutipes) cultivar was less depressed by T. pseudokoningii, but had a lower cross growth rate than the other four cultivars.

• Journal of Korean Foot and Ankle Society
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• v.15 no.2
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• pp.51-57
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• 2011

Pilon fractures involving distal tibia remain one of the most difficult therapeutic challenges that confront the orthopedic surgeons because of associated soft tissue injury is common. To introduce and describe the diagnosis, current treatment, results and complications of the pilon fractures. In initial assessment, the correct evaluation of the fracture type through radiographic checkup and examination of the soft tissue envelope is needed to decide appropriate treatment planning of pilon fractures. Even though Ruedi and Allgower reported 74% good and excellent results with primary open reduction and internal fixation, recently the second staged treatment of pilon fractures is preferred to orthopedic traumatologist because of the soft tissue problem is common after primary open reduction and internal fixation. The components of the first stage are focused primarily on stabilization of the soft tissue envelope. If fibula is fractured, fibular open reduction and internal fixation is integral part of initial management for reducing the majority of tibial deformities. Ankle-spanning temporary external fixator is used to restore limb alignment and displaced intraarticular fragments through ligamentotaxis and distraction. And the second stage, definitive open reduction and internal fixation of the tibial component, is undertaken when the soft tissue injury has resolved and no infection sign is seen on pin site of external fixator. The goals of definitive internal fixation should include absolute stability and interfragmentary compression of reduced articular segments, stable fixation of the articular segment to the tibial diaphysis, and restoration of coronal, transverse, and sagittal plane alignments. The location, rigidity, and kinds of the implants are based on each individual fractures. The conventional plate fixation has more advantages in anatomical reduction of intraarticular fractures than locking compression plate. But it has more complications as infection, delayed union and nonunion. The locking compression plate fixation provides greater stability and lesser wound problem than conventional implants. But the locking compression plate remains poorly defined for intraarticular fractures of the distal tibia. Active, active assisted, passive range of motion of the ankle is recommended when postoperative rehabilitation is started. Splinting with the foot in neutral is continued until suture is removed at the 2~3 weeks and weight bearing is delayed for approximately 12 weeks. The recognition of the soft tissue injury has evolved as a critical component of the management of pilon fractures. At this point, the second staged treatment of pilon fractures is good treatment option because of it is designed to promote recovery of the soft tissue envelope in first stage operation and get a good result in definitive reduction and stabilization of the articular surface and axial alignment in second stage operation.