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Caching efficiency is critical to performance when an in-memory database system acts as a cache for a disk-oriented database system. Memcached, one of the widely used in-memory database that stores key-values, roles as a cache for high-speed data storage layer. It replaces items using LRU replacement policy when memory capacity is used up. Other than LRU policy for maximizing temporal locality, in this paper, we confirm the impact of replacement policies for workloads with random pattern operations. We analyze hit counts of workload by applying BIP and SRRIP replacement policies to Memcached. Experimental results show that hit counts of Memcached to which SRRIP is applied is improved by up to 12%.

For future exascale computing systems, ultra-high-density memories would be required that consume low power to process massive data. Of the various memory devices, 3D-stacked DRAMs using TSVs are a perfect solution for this purposes. In addition to providing high capacity, these provide functional flexibility to the computing system by attaching a logic die in each 3D-stacked DRAM chip. However, the high capacity 3D-stacked DRAMs suffer from a significant loss of refresh power, which is solely required to maintain data. Although various schemes have been proposed to mitigate this issue, they cannot be adopted by commercial products due to compatibility issues. To tackle this issue, we propose EXTREME, which effectively reduces the refresh power of 3D-Stacked DRAMs. In order to retain the compatibility with OS, a simple page table manager is implemented at the logic die of 3D-stacked DRAM devices, which pins the page table to a specific memory space. The experiment results demonstrate that this reduces the refresh power at idle time by up to 98 percent with 16 KB of SRAM (static RAM) and 64 KB of DRAM register overhead for a 2 GB 3D-stacked DRAM device.

This study analyzes Korean firms’ motives for cross-border M&As, Asia’s representative emerging capital market, from the perspective of financial attributes, and defines the effects of group attributes of cross-border M&As on the wealth of acquiring firms’ shareholders. As for the group attributes of cross-border M&As, shareholders of small firms with high ROA do not like cross-border M&As, because the shareholders of small acquiring firms with sufficient internal growth factors are reluctant to transfer their present wealth to shareholders of foreign target firms. We also verify that the diversification effect with regard to cross-border M&As is accompanied by the diversification discount, but that firms with ample internal funds due to their high ROA like entering into new industries through cross-border M&As. Lastly, when target companies are listed in countries with highly uncertain GDP growth rates, acquiring firms’ value decreased.

The deposition techniques of quantum dots (QDs) have great influence on the photovoltaic performances of quantum dot sensitised solar cells (QDSSCs). In this study, we report CdS/CdSe sensitised TiO2 solar cells focussing on the influence of two commonly used in situ QD deposition techniques (SILAR: successive ionic layer adsorption and reaction and CBD: chemical bath deposition). In addition to this, the QDSSC performance is enhanced due to better light harvesting capability of PbS quantum dots and makes large accumulation of photo-injected electrons in the conduction band of TiO2. When compared to power conversion efficiency (PCE) of 4.58% was obtained for PbS/CBD-CdS/CBD-CdSe cells when compared to PbS/SILAR-CdS/SILAR-CdSe. With chemical bath deposition, we achieved high surface coverage of QDs, which contributes to the increase in photocurrent,open circuit voltage and fill factor. Impedance spectroscopy revealed that the PbS/CBD-CdS/CBD-CdSe reduces recombination and increases charge collection efficiency and a long electron lifetime was achieved. To associate the assembling of QDs with the performance of QDSSCs a methodical characterization of morphology, optical and electro-chemical properties and its stability has been studied. We achieved PbS seeded CBD highlighting its robust consequences for the performance of QDSSCs.

Purpose: This study evaluated the preoperative and postoperative radiologic findings of patients with complete repairs after massive rotator cuff tears along with the incidence of re-tear and the clinical outcomes. Materials and methods: This study evaluated 33 cases who had open complete repairs for massive rotator cuff tears and these patients were followed up for more than 24 months. The clinical evaluation was performed according to the shoulder joint function test of the American Shoulder and Elbow Surgeons (ASES), and the degree of arthritis related to the massive rotator cuff tears was evaluated using the Hamada classification. Results: The ASES scores improved from 37.6 preoperatively to 85.6 postoperatively. The mean preoperative acromio-humeral interval (AHI) score was 6.5 mm, which increased to 9.3 mm immediately after surgery, and there was a decreased to 6.5 mm noted at the last follow up. The lower radiology stages of arthritis according to the classification showed better preoperative and postoperative results. Conclusion: An open complete repair as the surgical treatment for a massive rotator cuff tear showed satisfactory results for pain relief and an improvement in the shoulder joint function though re-tear after surgery.

Background To determine the association between lunate morphology and the scapholunate instability using radiographic images, and investigate the association between lunate morphology and scaphoid fracture location. Methods Between January 2003 and December 2011, we retrospectively evaluated the plain radiographs and computed tomography (CT) images of 70 patients who underwent surgical intervention for a scaphoid nonunion, in order to determine the association between lunate type (I or II) and scapholunate instability or scaphoid fracture location. We determined the scaphoid fracture location using the fragment ratio and measured the radiolunate angle and capitate-triquetrum (C-T) distance. Results A type II lunate was present in 68.6% (48 of 70 cases). Mean fragment ratio of fracture location was 50.6% in the type II lunate group and 56.2% in the type I lunate group (p = 0.032). Sixteen of the 70 patients had dorsal intercalated segmental instability (DISI) deformities. Nine of 22 cases showed DISI deformity in type I lunate and 7 of 48 cases showed DISI deformity in type II lunate (p = 0.029). However, there were no significant differences between the presence of DISI deformity and fracture location (p = 0.15). Morphologic comparisons by both plain radiography and CT indicated a mean C-T distance in the type I lunate group (22 cases) of 2.3 mm and 5.0 mm in the type II lunate group (48 cases). The C-T distances were significantly correlated with lunate morphology (p = 0.001). Conclusions A type II lunate was associated with low incidence of DISI deformity and proximal location of fracture in patients presenting with a scaphoid nonunion.

To describe prominent premalar and cheek swelling as a previously undescribed clinical feature of thyroid-associated orbitopathy (TAO).Retrospective interventional case series.A retrospective case review of patients with prominent premalar and/or cheek swelling and TAO was undertaken. All patients who presented from March 2002 to February 2005 with complaints of premalar and/or cheek swelling in TAO were analyzed.Six female patients between the ages of 28 and 66 years (average, 44.2 years) who had complaints of prominent premalar and/or cheek swelling and TAO were included in the study, among 326 new patients with TAO (incidence: 1.84%). Five of the 6 patients had Graves hyperthyroidism. One initially had Hashimoto thyroiditis, which converted to Graves hyperthyroidism. In all cases, TAO preceded the thyroid disease or developed simultaneously (average time from TAO to thyroid disease was 3.0 months). No patient had received corticosteroids before premalar and/or cheek swelling. The premalar and/or cheek swelling was bilateral in all cases, but 2 of 6 were asymmetric. No diurnal fluctuation or tenderness in premalar and/or cheek swelling was noted. All improved incompletely over several months. Brow, eyelid swelling, and orbital-fat hypertrophy on radiologic examination was coincidentally noted in 5 of 6 cases. Pretibial myxedema was noted in one case. One case was associated with another autoimmune disease (rheumatoid arthritis).Prominent premalar and cheek swelling should be considered among the clinical features of TAO. The true incidence will become apparent as we question and examine patients more carefully regarding this entity and as we review premorbid photographs.

The Mokpo cable-stayed bridge has become a new landmark in Mokpo city, Korea. This bridge has a unique feature from an aesthetic and structural point of view and will be the second longest cable-st...

A design procedure for a structure's monitoring system using sensitivity analysis and a neural network is developed. The monitoring system is to be used to monitor damage to members critically affecting the overall safety of structures. Recently, many techniques for evaluating the damage of isolated members and models of simple structures have been investigated. However, actual structures are large, and their complex behavior may not be based on damage of isolated members or their simple models. To monitor large structures realistically, structures' data on behavior at many points need to be monitored. Identifying the optimal locations and numbers of these monitoring points and assessing the safety of the entire structure from the limited data are the monitoring system design problem. The procedure presented for this design problem is a two-step process. In the first step, using sensitivity analysis and damage-assessment techniques, individual members are ranked according to their influence on the failure probability of the entire structure or according to their effect on the abnormal behavior of the structure. Based on the rank, critical members are identified. In the second step, sensitivity analysis and a neural network are used to determine the optimal locations. In addition, the optimal number of sensors for monitoring damage to the critical members selected in step 1 is also suggested. Truss and frame examples are used to show the validity and applicability of the monitoring system design procedure.

Picture archiving and communications system (PACS) is widely used in hospitals to bring high efficiency in a medical process. Recently, PACS is required to evolve into a more sophisticated system that can communicate with other medical systems. The existing PACS was designed to be used in a local area network (LAN) of a hospital and DICOM, the standard used in PACS, doesn't have any QoS for file transmission or security functions for an open network. Therefore, we propose a PACS system over Policy Quorum based Resource Management (PQRM) system, which manages storage resources and computing resources in Grid environment to provide satisfying advanced medical services with guaranteed QoS. Finally, we test the real situation medical scenario to prove the advanced functions our system provides and do several experiments to show the superiority of our novel system to existing PACS systems. The results indicate that while PQRM-based PACS providing the ability for advanced medical services it guarantees the transmission, provides best resource selection and disaster recovery capability.

Picture archiving and communications system (PACS) is widely used in hospitals to take medical images, to send images to radiologists or doctors and to store images into storage in a digital manner, that has brought high efficiency in a medical process. Recently, PACS is required to evolve into a more sophisticated system that can communicate with other medical systems. The existing PACS was designed to be used in a Local Area Network (LAN) of a hospital and DICOM, the standard used in PACS, doesn't have any QoS for file transmission or security functions for an open network. Therefore, we propose a PACS system over Policy Quorum based Resource Management (PQRM) system, which manages storage resources and computing resources in Grid environment to provide satisfying advanced medical services with guaranteed QoS. Finally, we test the real situation medical scenario to prove the advanced functions our system provides and do several experiments to show the superiority of our novel system to existing PACS systems. The results indicate that while PQRM-based PACS providing the ability for advanced medical services it guarantees the transmission, provides best resource selection and disaster recovery capability.

Picture archiving and communications system (PACS) is widely used in hospitals to take medical images, to send images to radiologists or doctors and to store images into storage in a digital manner, that has brought high efficiency in a medical process. Recently, PACS is required to evolve into a more sophisticated system that can communicate with other medical systems. The existing PACS was designed to be used in a local area network (LAN) of a hospital and DICOM, the standard used in PACS, doesn't have any QoS for file transmission or security functions for an open network. Therefore, we propose a PACS system over policy quorum based resource management (PQRM) system, which manages storage resources and computing resources in Grid environment to provide satisfying advanced medical services with guaranteed QoS. Finally, we test the real situation medical scenario to prove the advanced functions our system provides and do several experiments to show the superiority of our novel system to existing PACS systems. The results indicate that while PQRM-based PACS providing the ability for advanced medical services it guarantees the transmission, provides best resource selection and disaster recovery capability.

The mission-critical application, in particular e-health service such as ECG application and carotid artery application, normally demands the highly sophisticated handling method and reliable processing scheme in wireless grid environments. Due to the huge amounts of data set from the numerous wireless devices, we propose the refined procedures based on wireless grid to guarantee the optimal processing time and reliability as prime factor of the system performance by using the proposed scheduling scheme. The simulation results show that proposed load scheduling can support the load balancing and guarantee the high system availability.

Choristoma is a benign tumour defined as normal tissue in an ectopic location. Osseous choristoma, one subtype of this entity, occurring within the orbit has rarely been reported in the world literature. We report a 6-year-old girl with bilateral ocular osseous choristomas who presented with palpable nodules protruding from both upper lids. The radiological and clinical findings are described and previous reports are reviewed.

This paper presents a digital control scheme for a UPS inverter system. The inverter provides a near sinusoidal output voltage waveform with low harmonic distortion factor and must be controlled with very fast dynamic response and robustness to load changes or parameter variations. The proposed scheme is based on the current regulated voltage controller. The filter inductor current is forced to follow the current command calculated from the desired capacitor voltage and the sensed output load current. Clearly, the sensed output current signal acts as a disturbance feedforward signal which leads to a fast dynamic response of the controller to sudden changes of output load current. In order to guarantee the robustness of the system, a PI capacitor voltage controller is added as in the conventional double feedback loop controller. The natural problems of this controller, i.e. the phase difference between the output voltage and its reference caused by the AC quantity of the feedback signal, are compensated by using a synchronization controller for the output voltage phase and frequency. The algorithm of the proposed scheme is described and digital simulation and experimental results from a 5 kVA prototype are provided for verification.

A novel digital control scheme of a UPS inverter based on the double control strategy is proposed. This method consists of a inner voltage regulated current controller and an outer current regulated voltage controller. In order to improve the dynamic response, the voltage controller has a load predictive feedforward loop and the current controller has an output voltage feedforward loop. PI compensators included in each of the voltage and current controllers are used to guarantee the robustness of the system. The mathematical model and the control algorithm of the proposed scheme are described and digital simulation and experimental results for a 5 kVA prototype are provided to verify the validity of the proposed double control strategy.

Purpose To descirbe a series of patients in which Thyroid Associated Orbitopathy (TAO) occurred after periocular surgery. Methods A retrospective case review of patients who developed TAO in close temporal association with periocular surgical interventions and presented at the orbital clinic from 1997 to 2004. History of previous thyroid abnormality and the lack of TAO signs and symptoms before surgery were reviewed and analyzed. Results Nine patients that developed TAO in association with periocular surgery were identified. All were women with an average age of 59.3years. (range: 45-75 years). The patients divided into two groups. Group 1 consisted of four patients who had previously been diagnosed with Graves' hyperthyroidism (GH). They ranged in age from 48 to 75 years (average: 58.8 years). The diagnosis of GH had been made an average of 50.5 months (range: 12-96 months) before presentation with TAO. Group 2 consisted of five patients who had no previous history of thyroid abnormality. They ranged in age from 45 to 74 years (average: 60.2 years). No patients had any signs or symptoms of TAO before their recent presentation. Conclusions Periocular surgery may lead to local inflammatory events that may contribute to the instigation of TAO in predisposed individuals.