Objective: To describe changes of intraocular pressure (IOP) in horses affected by uveitis. Procedure: Study of medical records of 9 racehorses with unilateral uveitis (4 acute and 5 chronic) where were measured using a handheld applanation tonometer. Results: At first tonometry of the 9 horses, of the affected eyes (16.5 ± 5.1 mmHg) were significantly lower than those of the contralateral eyes (23.9 ± 4.7 mmHg). Two of the acute cases had lower in the affected eyes compared to the normal eyes, and changes in the IOP were monitored during treatment. Although both cases improved clinically, IOP recovered only in 1 case. In 4 of the chronically affected cases, uveitic eyes had developed phthisis bulbi and 3 of these eyes showed lowered IOP whereas the rest had IOP equivalent to the contralateral eye. The other chronic case, which had been affected by nonulcerative keratouveitis, had lowered IOP in the affected eye for 6 months, however, IOP difference between the both eyes got smaller. Conclusions: IOP can decrease with variable extent and duration in equine uveitis patients as well as in dogs [7]. However, IOP values of the affected equine eyes in this study were often higher than those of uveitic canine eyes [7]. Minor changes of IOP in uveitic eyes could be detected more accurately by tonometry than by observing or palpating the globes. IOP difference greater than 5 mmHg in each individual was considered to be a useful indicator in diagnosis of equine uveitis. Although further study is required, tonometry is a useful method to understand equine uveitis in detail, and should be included in complete ophthalmic examination especially in cases where the problem is longstanding and/or clinical progression is minor.

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NAND flash memories used in solid-state drives (SSDs) will be replaced with storage-class memories (SCMs), which are comparable with NAND flash in their cost, and with DRAM in their speed. This paper describes the performance difference of the SCM/NAND flash hybrid SSD and the SCM-based SSD with between sector-unit read (512 Byte) and page-unit read (16 KByte, NAND flash page-size) using synthetic and real workload. Also, effect of the SCM read-unit size on SSD performance are analyzed. When SCM write/read latency is 0.1 us, performance difference of the SCM/NAND flash hybrid SSD with between page- and sector-unit read is about 1% and 6% at most for the write-intensive and read-intensive workloads, respectively. However, performance of the SCM-based SSD is significantly improved when sector-unit read is used because extra read latency does not occur. Especially, the SCM-based SSD

is improved by 131% for proj_3 (read-hot-random), because its read request size is small but its read request ratio is large. This paper also shows of SCM-based SSD write/read with sector-unit read can be predicted by the average write/read request size of workloads.

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This paper analyzes the system-level performance of Storage Class Memory (SCM)/NAND flash hybrid solid-state drives (SSDs) and SCM/NAND flash/NAND flash tri-hybrid SSDs in difference types of NAND flash memory. There are several types of NAND flash memory, i.e. 2-dimensional (2D) or 3-dimensional (3D), charge-trap type (CT) and floating-gate type (FG) and multi-level cell (MLC) or triple-level cell (TLC). In this paper, the following four types of NAND flash memory are analyzed: 1) 3D CT TLC, 2) 3D FG TLC, 3) 2D FG TLC, and 4) 2D FG MLC NAND flash. Regardless of read- and write-intensive workloads, SCM/NAND flash hybrid SSD with low cost 3D CT TLC NAND flash achieves the best performance that is 20% higher than that with higher cost 2D FG MLC NAND flash. The performance improvement of 3D CT TLC NAND flash can be obtained by the short write latency. On the other hand, in case of tri-hybrid SSD, SCM/3D CT TLC/3D CT TLC NAND flash tri-hybrid SSD improves the performance 102% compared to SCM/2D FG MLC/3D CT TLC NAND flash tri-hybrid SSD. In addition, SCM/2D FG MLC/2D FG MLC NAND flash tri-hybrid SSD shows 49% lower performance than SCM/2D FG MLC/3D CT TLC NAND flash tri-hybrid SSD. Tri-hybrid SSD flash with 3D CT TLC NAND flash is the best performance in tri-hybrid SSD thanks to larger block size and word-line (WL) write. Therefore, in 3D CT TLC NAND flash based SSDs, higher cost MLC NAND flash is not necessary for hybrid SSD and tri-hybrid SSD for data center applications.

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This paper analyzes the optimal SSD configuration including emerging non-volatile memories such as quadruple-level cell (QLC) NAND flash memory [1] and storage class memories (SCMs). First, SSD performance and SSD endurance lifetime of hybrid SSD are evaluated in four configurations: 1) single-level cell (SLC)/QLC NAND flash, 2) SCM/QLC NAND flash, 3) SCM/triple-level cell (TLC)/QLC NAND flash and 4) SCM/TLC NAND flash. Furthermore, these four configurations are compared in limited cost. In case of cold workloads or high total SSD cost assumption, SCM/TLC NAND flash hybrid configuration is recommended in both SSD performance and endurance lifetime. For hot workloads with low total SSD cost assumption, however, SLC/QLC NAND flash hybrid configuration is recommended with emphasis on SSD endurance lifetime. Under the same conditions as above, SCM/TLC/QLC NAND flash tri-hybrid is the best configuration in SSD performance considering cost. In particular, for prxy_0 (write-hot workload), SCM/TLC/QLC NAND flash tri-hybrid achieves 67% higher

/cost than SCM/TLC NAND flash hybrid. Moreover, the configurations with the highest /cost in each workload and cost limit are picked up and analyzed with various types of SCMs. For all cases except for the case of prxy_1 with high total SSD cost assumption, middle-end SCM (write latency: 1us, read latency: 1us) is recommended in performance considering cost. However, for prxy_1 (read-hot workload) with high total SSD cost assumption, high-end SCM (write latency: 100ns, read latency: 100ns) achieves the best performance.

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　本研究では，沿岸域の複雑な光学特性を考慮した海色リモートセンシングのための合成データの構築方法を提案した．合成データの構築にあたり，東京湾で収集した固有光学特性（

），水質の実測値を使用し，放射伝達計算の有効性を確認した．また，階層クラスタリングによりと水質項目を関連づけて分類し，生物光学モデルに組み込むことで植物プランクトンの種の変遷，陸域と内部生産起源の有色溶存有機物（CDOM）や無機態懸濁物質とデトリタスとの光学特性の違いを表現可能な合成データの構築法を考案した．作成したR_rs，の合成データは，実測値との比較や既存の推定アルゴリズムへの適用を通して，概ね現実に則した合成データが作成されたことが確認できた．

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Many kinds of nanocarriers are attracting attention for DDS. Nanocarriers are required to have functions of loading, delivering and controlled release of drug. For this purpose, we propose and synthesize a nanocarrier by using magnetic iron oxide nanoparticles and gelatin. Iron oxide is chosen as a magnetic material because of its properties such as magnetically guided accumulation and heat generation under alternating magnetic fields as well as biodegradability. Gelatin shows sol-gel transition, which can support drugs in network structure of gel and release drugs in sol phase. To synthesize the carrier, iron oxide nanoparticles (

) prepared by co-precipitation and modified with citric acid work as a cross-linker to form gelatin particles. The role of citric acid is not only improving the dispersibility of but also introducing functional groups to combine with gelatin. Concentrations of and gelatin in the solution are important parameters to control the morphology of the composite particles, leading to the formation of the particles of 50～200 nm in size under the optimum conditions. Doxorubicin as an anti-cancer drug is incorporated in the composite particles and is released by a thermal stimulation.

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In order to realize solid-state drives (SSDs) with high performance, low energy consumption and high reliability, storage class memory (SCM)/multi-level cell (MLC) NAND flash hybrid SSD has been proposed. Algorithm of the hybrid SSD should be designed according to SCM specifications and workload characteristics. In this paper, SCMs are used as non-volatile cache. Cache operation guidelines and optimal SCM specifications for the hybrid SSD are provided for various workload characteristics. Three kinds of non-volatile cache operation for the hybrid SSD are discussed: i) write cache, ii) read-write cache without space control (RW cache) and iii) read-write cache with space control (RW cache w/ SC). SSD workloads are categorized into eight according to read/write ratio, access frequency and access data size. From evaluation result, the write cache algorithm is suitable for write-intensive workloads and read-cold-sequential workloads, while the RW cache algorithm is suitable for read-cold-random workloads to achieve the highest performance of the hybrid SSD. In contrast, as for read-hot-random workloads, write cache is appropriate when the SCM capacity is less than 3% of the NAND flash capacity. On the other hand, RW cache should be used in case that SCM capacity is more than 5% of NAND flash capacity. The effect of Memory-type SCM (M-SCM) and Storage-type SCM (S-SCM) on the hybrid SSD performance is also analyzed. The M-SCM latency is below 1 us (high speed) but the capacity is only 2% of the NAND flash capacity (small capacity). On the other hand, the S-SCM capacity is assumed to be 5% of the NAND flash capacity (large capacity) but S-SCM speed is larger than 1 us (low speed). If the additional SCM cost is limited to 20% of MLC NAND flash cost, up to 7-times and 8-times performance improvement are achieved in write-hot-random workload and read-hot-random workloads, respectively. Moreover, if the additional SCM cost is the same as MLC NAND flash cost, M-SCM/MLC NAND flash hybrid SSD achieves 24-times performance improvement.

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Previous works have studied the throughput allocation of the heterogeneous storage system consisting of SSD and HDD in the dynamic setting where users are not all present in the system simultaneously, but those researches make multiple servers as one large resource pool, and cannot cope with the multi-server environment. We design a dynamic throughput allocation mechanism named DAM, which can handle the throughput allocation of multiple heterogeneous servers in the dynamic setting, and can provide a number of desirable properties. The experimental results show that DAM can make one dynamic throughput allocation of multiple servers for making sure users' local allocations in each server, and can provide one efficient and fair throughput allocation in the whole system.

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This study proposes a heterogeneous integration of precise and approximate storage in data center storage. The storage control engine allocates precise and error-tolerant applications to precise and approximate storage, respectively. The appropriate use of both precise and approximate storage is examined by applying a non-volatile memory capacity algorithm. To respond to the changes in application over time, the non-volatile memory capacity algorithm changes capacity of storage class memories (SCMs), namely the memory-type SCM (M-SCM) and storage-type SCM (S-SCM), in non-volatile memory resource. A three-dimensional triple-level cell (TLC) NAND flash is used as a large capacity memory. The results indicate that precise storage exhibits a high performance when the maximum storage cost is high. By contrast, with a low maximum storage cost, approximate storage exhibits high performance using a low bit cost approximate multiple-level cell (MLC) S-SCM.

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Flash storage suffers from severe performance degradation due to its inherent internal synchronization overhead. Especially, flushing an L2P (logical address to physical address) mapping table significantly contributes to the performance degradation. To relieve the problem, we propose an efficient L2P mapping table management scheme on the flash storage, which works along with a small-sized NVRAM. It flushes L2P mapping table from DRAM to NVRAM or flash memory selectively. In our experiments, the proposed scheme shows up to 9.37× better performance than conventional schemes.

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Aiming at the demand for FPGA-based high-bandwidth NVMe SSD host access, this letter presents an NVMe over PCIe Hardware Acceleration Engine (NoPHAE), which has two innovative aspects. Firstly, an NVMe Queues Engine is integrated into the NoPHAE to enhance I/O performance and reduce resource consumption. The NVMe Queues Engine provides dynamic queue configuration and introduces a virtual completion queue, which reduces resource consumption by 20%. Secondly, a PCIe Acceleration Engine is built in the NoPHAE, which implements the co-design of PCIe and NVMe and optimizes the timing for processing PCIe transport layer transactions, resulting in a significant increase in data throughput. Test results indicate that the sequential read and write speed of the NoPHAE is 7.93 times faster than that of the baseline, and the random read and write performance is two times faster than that of the baseline.

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We propose a technique called the central processing unit (CPU) Load Balancing method for Semi-Symmetric Active-Active dual controller storage systems to maintain load balancing between dual controllers by migrating logical unit (LU) ownerships from one controller to another, even if there are inhomogeneous operations between controllers. We develop a performance simulator and use it to evaluate the proposed method's operation. Our findings reveal that the proposed approach improves the average response time on continuous stable load by 2% and the system throughput by 18% compared to the conventional method. The CPU Load Balancing method is a better choice especially to achieve improvements in storage operability. In addition, our findings reveal that the proposed approach improves the average response time in simulated actual loads by 27% compared to the conventional method.

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Cloud bursting is used to offload processing to the cloud when on-premise data centers run out of computing resources. Data in the on-premise data center needs to be copied to the cloud at the start of cloud bursting. Since data capacity and usage of connection between on-premise data center and cloud vary, the time required to build a cloud bursting environment will vary. This made it difficult to determine a configuration that could resume processing within the recovery time objective at a low cost in the event of a failure in the cloud. In this study, we proposed a redundancy determination method based on reliability requirements that estimates the time required to build a cloud bursting environment considering data capacity and the usage of connection between on-premise data centers and the cloud, and determines a configuration that satisfies recovery time objective at low cost. Assuming the case of cloud bursting of data analysis processing, we conducted an experiment in which a system simulating an analysis application was cloud bursted from an AZ simulating an on-premise data center to the main AZ, and the range of the system built in advance in the sub AZ was changed to simulate a sub AZ failure and failover to the sub AZ. As a result, it was confirmed that the time required for failover can be reduced by increasing the extent to which the system is preconstructed in the sub AZ. The proposed method is expected to enable us to determine a configuration that can meet the recovery time objective at a low cost.

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This paper presents Hexa-SSD, a novel SSD-internal DRAM management scheme that allows the SSD capacity to scale beyond the slow growth of capacitors. Hexa-SSD judiciously manages the dirty memory footprint within the SSD-internal buffer by using a low-overhead data reordering scheme on the deep queues available in today’s storage interfaces. In doing so, our design guarantees crash consistency while using a fraction of the capacitors compared to the state-of-the-art designs. We implement our design in FEMU and demonstrate that Hexa-SSD delivers up to 1.4× higher

and up to 49% less write amplification compared to the existing scheme under power constraints.

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酸化鉄ナノ粒子を熱分解法と共沈法の二種類の方法で合成し, その発熱特性と磁気物性を評価した. 熱分解法では, 鉄原料である鉄ペンタカルボニルとオレイン酸 (C₁₇H₃₃COOH) をジオクチルエーテル中に投入し, 大気中で560 Kで反応させることで酸化鉄ナノ粒子を合成した. C₁₇H₃₃COOHの添加量と反応時間を変化させて得られた試料を透過型電子顕微鏡 (TEM) によって観察した結果, 酸化鉄ナノ粒子の平均粒子径は反応条件に応じて3.0 nmから12.2 nmまで変化した. 一方, 共沈法では硫酸鉄 (II) 水溶液と塩化鉄 (III) 水溶液の混合液をアンモニア水に添加して酸化鉄ナノ粒子を作製した. TEM像観察から, 共沈法により作製した酸化鉄ナノ粒子の平均粒子径は10.2 nmと見積もられた. それぞれの方法で作製した酸化鉄ナノ粒子をイソパラフィン系溶媒に分散させ, 周波数600 kHz, 磁場強度3.2 kA/mの交流磁場を印加して温度変化を測定した. この結果, 共沈法により作製した試料は77 Kの温度上昇を示した一方, 熱分解法により作製した平均粒子径11.3 nmの試料では14 Kの温度上昇を示した. これに対して, 平均粒子径3.0 nmの酸化鉄ナノ粒子では有意な温度上昇は観測されなかった. 試料の磁気物性を超伝導量子干渉型磁束計と物理特性測定システムを用いて評価した結果, 発熱効率の高い試料では磁化率が極大となる温度, ブロッキング温度が高くなることが明らかになった.

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A general approach is presented to quantify retrieval errors in in-water constituent concentra tions induced by uncertainty in inherent optical property (IOP) submodel parameterization. Chlo rophyll concentrations are retrieved by inverting a radiance model with nonlinear IOP submodels. We demonstrate quantitatively how uncertainty in the IOP submodel parameterization influences the accuracy of the chlorophyll concentration retrieval at different chlorophyll concentration lev els. Two complete sets of simulations were designed and conducted, representing two extreme cases between which ”real” cases are expected to occur. The simulations show that precise knowl edge of spectral shapes of IOP submodels is important in chlorophyll retrieval.

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The effects of electroacupuncture (EA) on intraocular pressure (IOP) and hemodynamic parameters were evaluated in isoflurane anesthetized 10 (5 males, 5 females) normal mongrel dogs (8.1-9.8 kg, 6-8 years old). After determination of baseline IOP and hemodynamic parameters (cardiac index, systolic arterial pressure, diastolic arterial pressure, heart rate and systemic vascular resistance index), EA was applied at 3 acupoints (LI-4, LIV-3 and GB-37) for 20 min. After the EA treatment, IOP was significantly decreased in the both eyes (p<0.05). However, there were not significant differences in hemodynamic parameters between those of before and after EA treatment. From these results, the EA treatment at LI-4, LIV-3 and GB-37 would be considered one of the valuable methods for the IOP treatment in dogs.

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We propose a method for shared file cache function for cloned files used by virtual machines, called SCC. The file clone function copies the files faster than conventional (read and write) method. Moreover, the function reduces disk spaces. The function is used to deploy virtual machines in virtual desktop infrastructure because of fast copying a lot of virtual machine disk files. SCC uses the file cache of a shared file as a shared cache among cloned files. The cached data on the shared file are returned to application programs on accessing the shared file via cloned files. Therefore, SCC improves the I/O performance of the shared file due to avoiding disk accesses. In this paper, we implement SCC and evaluate the I/O performance. From the evaluation, we have found SCC improves I/O throughput about 38 times in the case of random read and shared cache hit.

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This study was performed to evaluate changes in intraocular pressure (IOP) during standard coaxial phacoemulsification using 4 different bottle heights (BHs) and 2 different incision sizes. Coaxial phacoemulsification was performed with a venturi-based machine in 8 enucleated canine eyes through 3.0 and 3.2 mm clear corneal incisions (CCIs). A pressure transducer inserted in the peripheral cornea monitored the IOP in real-time. The surgery was subdivided into 4 stages: sculpt-segment removal, irrigation/aspiration, capsular polishing and viscoelastic removal. The mean IOP and the difference between the maximum and minimum were calculated at each stage and compared. The ultrasound time and volume of irrigation fluid used were recorded. The mean IOP increased with an elevation in the BH. The mean IOP in the irrigation/aspiration stage was significantly higher than that in the sculpt-segment removal stage at the same BH. The difference between the maximum and minimum IOP at each stage was greater in the 3.2 mm than the 3.0 mm CCIs, although the mean IOP was lower with the 3.2 mm than the 3.0 mm CCIs. The ultrasound time and irrigation fluid volume were greater with the 3.2 mm than the 3.0 mm CCIs. Therefore, fluidic parameters during each stage could be reassessed and adjusted to reduce complications arising from an elevated IOP. Phacoemulsification with 3.0 mm CCIs at a lower BH might lead to less stress on the eye from IOP fluctuations, ultrasound energy and irrigation fluid.

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