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As high-grade and easily exploitable copper ores have been getting depleted, the development of flotation techniques for copper ores with low-grade and small grain size is becoming an important issue. To process these kinds of ores, fine grinding is essential to achieve sufficient liberation; however, flotation rate of finely ground minerals ( The addition of anionic emulsifiers (SDS, KAX) could stabilize the oil–water emulsion and produce smaller oil droplets, which improve Cu recovery in the agglomeration-flotation of chalcopyrite and quartz from ~68% (without emulsifier) to >97% (with emulsifier). When Ca2+ and quartz co-existed, the amounts of SDS used as emulsifier were reduced due to its adsorption onto the surface of Ca2+ activated quartz, which caused the coalescence of oil droplets resulting in low Cu recovery (i.e., 81% with quartz only; 44% with quartz and Ca2+). Meanwhile, emulsified oil stabilized by KAX was not affected by the presence of Ca2+ and quartz, and high Cu recovery (~83%) could be obtained.

Flotation is the conventional method for processing porphyry copper deposits, one of the most economically important sources of copper (Cu) worldwide. The rapidly decreasing grade of this type of Cu ore in recent years, however, presents serious problems with fine particle recovery using conventional flotation circuits. This low recovery could be attributed to the low collision efficiency of fine particles and air bubbles during flotation. To improve collision efficiency and flotation recovery, agglomeration of finely ground chalcopyrite (CuFeS2) (D50 = 3.5 &mu, m) using emulsified oil stabilized by emulsifiers was elucidated in this study. Specifically, the effects of various types of anionic (sodium dodecyl sulfate (SDS), potassium amyl xanthate (KAX)), cationic (dodecyl amine acetate (DAA)), and non-ionic (polysorbate 20 (Tween 20)) emulsifiers on emulsified oil stability and agglomeration&ndash, flotation efficiency were investigated. When emulsifiers were added, the average size of agglomerates increased, resulting in higher Cu recovery during flotation. This dramatic improvement in flotation efficiency could be attributed to the smaller oil droplet size in emulsified oil and their higher stability in the presence of emulsifiers. The utilization of emulsifiers during agglomeration&ndash, flotation not only lowered the required agitation strength for agglomeration but also shortened the agglomeration time, both of which made the process easier to incorporate in existing flotation circuits.

Ectomycorrhizal fungal distributions at different distances from one mature Quercus serrata tree were demonstrated in a Japanese cypress stand. After 4 months for field-planted and 3 months for laboratory-incubated Q. serrata seedlings, they were evaluated ectomycorrhiza formations. For the field-planted seedlings, molecular discrimination was conducted to clarify the species diversity of ectomycorrhizal fungi. Ectomycorrhiza formation was confirmed at all distances in both methods. However, the formation and associating fungal species were decreased with increasing distance. These results indicate that the density and diversity of ectomycorrhizal fungi decrease rapidly within several tens of meters from arbuscular mycorrhizal forest edges.

シカの生息密度が高い地域内で強度間伐 (本数間伐率47.5∼71.2％) を行った針葉樹人工林に獣害防護柵を設置し, 間伐後の広葉樹侵入に及ぼすシカ採食の影響を調査した。獣害防護柵内では先駆種を中心とする多数の広葉樹が間伐後に侵入し, その生残率は高く, 樹高成長も良好であった。しかし, 柵外では柵内よりも広葉樹の侵入が少なく, 生残率も低かったため, 2年後まで生残した個体はわずかであった。このことから, 柵外ではシカの採食により間伐後の広葉樹侵入が強く阻害されていると考えられた。シカ生息密度が高い地域において, 人工林の針広混交林への誘導を目指すには, 強度間伐を行った場合にシカ採食が顕在化する生息密度の解明と施業地へのシカの集中を防ぐ簡便な手法の開発が必要である。

三重県尾鷲地域のウラジロに覆われた再造林放棄地を森林再生するために，低コストで更新木に対するシカ食害を防止する手法の確立が求められている。再造林放棄地内でウラジロを坪刈してヒノキ苗木を植栽し，坪刈地内へのシカの侵入と植栽木の成長を2～3年間調査した。シカの坪刈地内への侵入頻度は斜面傾斜が急であるほど低い傾向があり，植栽木の樹高成長は植栽初年度の食害程度や2年目以降の頂枝食害頻度が低いほど大きい傾向が認められた。そのため，急傾斜の斜面部では，この手法によりシカ食害を防ぎつつ植栽木を育成できると考えられた。

Carbon graphite was expected to show affinity toward aromatics by using π–electron interaction. Novel membranes for pervaporation were prepared from carbon graphite (CG) and nylon 6 (N6). The composite membranes showed permselectivity toward benzene from benzene–cyclohexane mixtures. Benzene was permeated in preference to cyclohexane from benzene–cyclohexane mixtures and separation factor toward benzene reached to 435 at the weight fraction of benzene in feed of 0.1. From the sorption experiments, it was made clear that the introduction of CG into N6 enhances the solubility selectivity toward benzene and, as a result, benzene was preferentially permeated through the CG–N6 composite membranes.

When a real-time OS (RTOS) and a symmetric multiprocessing general purpose OS (SMP GPOS) are executed on the same multicore processor, there is a possibility to cause the lock holder preemption (LHP) problem, which is a well known problem of the sources of the performance degradation on an SMP GPOS. The problem occurs when a kernel mode thread holding a lock in a SMP GPOS is preempted by other OSes if these OSes share the same physical core. The existing solution does not take into account real-time responsiveness so it is not suitable to use in embedded systems. The paper proposes two new techniques to avoid the LHP problem for ensuring both the real-time responsiveness of real-time OS and the high throughput of SMP GPOS. The new proposed techniques have been implemented on our virtualization layer called SPUMONE, and we measured the results showing that the proposed new techniques reduce the LHP problem without degrading the real-time responsiveness.

System administrators have used integrity checkers to prevent the system from malicious infections. Especially, checking the integrity of the kernel is important, since the infections of the kernel affect the entire system. Most of the previous works to prevent such infections rely on the developers or administrators to write specifications to detect them. Those works require high engineering cost and may incur vulnerabilities. The other previous works use virtualization techniques to trace the memory usage of the target system. However, they require hardware supports for the virtualization to avoid significant overhead. Most of embedded systems do not have such hardware supports. In addition, the overhead of the integrity checking affects all of the guest OSes, because they check integrity of the target OS in the virtualization layer. Therefore, they are difficult to be applied to multi-core environment.In this paper, we propose a method to generate the integrity checker automatically. The integrity checker runs on a virtualization layer and checks the integrity of kernel data structures of the target OS kernel from the outside of it. The virtualization layer does not require a special hardware support for the virtualization, because the integrity checker only reads memory area used by the target OS. Moreover, the integrity checker is executed as a guest OS, and thereforeit does not affect the entire system performance when it runs on multicore environment. The integrity checker checks the kernel data structures using invariants of them. In order to generate the invariants automatically, our system analyzes obtained kernel data structures. However, checking all of the kernel data structures is not feasible, since there are a lot of kernel data structures and an analyzer uses relationships with them to generate invariants. Therefore, our challenge is to reduce the target kernel data structures while avoiding false positives and false negatives as much as possible.

In this paper, we introduce a lightweight processor abstraction layer named SPUMONE. SPUMONE provides virtual CPUs for respective guest OSes, and schedules them according to their priorities. In a typical case, SPUMONE schedules Linux with a low priority and an RTOS with a high priority. We first discuss why the traditional virtual machine monitor design is not appropriate for embedded systems, and how the features of SPUMONE allow us to design modern complex embedded systems with less efforts. Then, we describe two features of SPUMONE for the real-time resource management. SPUMONE also offers a novel mechanism to protect a critical component from malicious programs injected into the GPOS kernel.

In this paper, we propose a virtualization architecture for the multi-core embedded system to provide more sys-tem reliability and security while maintaining the same performance without introducing additional special hardware supports or having to implement complex protection mechanism in the virtualization layer. Embedded virtualization design usually uses two kinds of approaches, traditional VMM and microkernel approaches, but both of them suffer from performance or engineering cost problems. To achieve better reliability and keep the virtualization layer design light weighted, a common hardware component called local memory adopted in the multi-core embedded processors is used in this work. By taking this memory ar-chitecture's advantage, we can mitigate above-mentioned problems at once. We choose to re-map the virtualizationlayer's program called SPUMONE, which it runs all its guest systems in kernel space, on the local memory. By doing so, it can provide additional reliability and security for the entire system because the SPUMONE's design in a multi-core platform has each instance being installed on a separated processor core, which is different from the traditional virtualization layer design, and therefore the content of each SPUMONE in the local memory is inaccessible to each others.

In order to enhance OS security, most of people use security patches to fix the vulnerabilities of the OS. However, the security patches may also incur vulnerabilities. These vulnerabilities are generated since most OSes has a lot of functionalities and their functionalities are very complex to manage the entire source code manually. Moreover, in order to use the security patch, rebooting the system is required. Some of systems such as enterprise servers and embedded systems cannot accept the rebooting. Therefore, we propose an external integrity checking system to enhance the OS security. The external integrity checking system and a target OS run on a hyper visor simultaneously, therefore, their operations do not affect each other. In addition, the integrity checking system is generated automatically with invariants. Therefore, the possibility of inserting vulnerabilities into the system is as small as possible, and the system can cover a lot of vulnerabilities.

In this paper, we propose a composition kernel where multiple OS kernels are running on top of a very thin hardware abstraction layer. A composition kernel can reduce the engineering cost of developing an embedded system by reusing existing OS kernels and application with minimum modification without assuming special hardware supports.

Future ambient intelligence environments will embed powerful multi-core processors to compose various functionalities into a smaller number of hardware components. This makes the maintainability of intelligent environments better because it is not easy to manage massively distributed processors. A composition kernel makes it possible to compose multiple functionalities on a multi-core processor with the minimum modification of OS kernels and applications. A multi-core processor is a good candidate to compose various software developed independently for dedicated processors into one multi-core processor to reduce both the hardware and development cost. In this paper, we present SPUMONE which is a composition kernel for developing future smart products.