• 한국정밀공학회지
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• 제12권6호
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• pp.128-136
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• 1995

The problem addressed in this paper is that of the on-line computational burden of time-optimal control laws for quick, strongly nonlinear systems like revolute robots. It will be demonstrated that a large amount of off-line computation can be substituted for most of the on-line burden in cases of time optimization with constrained inputs if differential point-to- point specifications can be relaxed to cell-to-cell transitions. These cells result from a coarse discretization of likely swaths of state space into a set of nonuniform, contiguous volumes of relatively simple shapes. The cell boundaries approximate stream surfaces of the phase fluid and surfaces of equal transit times. Once the cells have been designed, the bang- bang schedules for the inputs are determined for all likely starting cells and terminating cells. The scheduling process is completed by treating all cells into which the trajectories might unex- pectedly stray as additional starting cells. Then an efficient-to-compute control law can be based on the resulting table of optimal strategies.

• 산업경영시스템학회지
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• 제22권49호
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• pp.59-65
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• 1999

This paper considers the cell formation in a manufacturing environment where the setup times and costs are significantly dependent on the sequence. The trade-off between saving on the setup costs and additional investment on new machines is considered for determining the economic number of cells. Accordingly, This paper develops a mixed integer program and mentions a variety of manufacturing situations where this model can be useful. This paper also includes an illustrative example.

• The Plant Pathology Journal
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• 제38권2호
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• pp.90-101
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• 2022

Pathogenicity of eight Bacillus strains to seedlings of four cotton cultivars was evaluated under greenhouse conditions. Each of the tested cultivars was individually treated with powdered inoculum of each bacterial strain. Untreated seeds were planted as control treatments in autoclaved soil. Effects of the tested strains on levels and activities of some biochemical components of the infected seedlings were also assayed. The biochemical components included total soluble sugars, total soluble proteins, total free amino acids, peroxidase, polyphenol oxidase, phenols, and lipid peroxidation. ANOVA showed that Bacillus strain (B) was a very highly significant source of variation in damping-off and dry weight. Cotton cultivar (V) was a nonsignificant source of variation in damping-off while it was a significant source of variation in dry weight. B × V interaction was a significant source of variation in damping-off and a nonsignificant source of variation in dry weight. Bacillus strain was the most important source of variation as it accounted for 59.36 and 64.99% of the explained (model) variation in damping-off and dry weight, respectively. The lack of significant correlation between levels and activities of the assayed biochemical components and incidence of damping-off clearly demonstrated that these biochemical components were not involved in the pathogenicity of the tested strains. Therefore, it was hypothesized that the pathogenicity of the tested strains could be due to the effect of cell wall degrading enzymes of pathogenic toxins. Based on the results of the present study, Bacillus strains should be considered in studying the etiology of cotton seedling damping-off.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 추계학술대회
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• pp.425-428
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• 2011

본 논문에서는 간단한 Maximum Power Point Tracking이 적용된 micro-scale의 빛에너지 하베스팅 회로를 제안한다. 에너지 변환기로는 온칩 PV cell 대신 이와 비슷한 출력을 하는 초소형 PV cell을 사용하였다. 적용된 MPPT는 PV cell의 개방전압($V_{OC}$)와 MPP전압($V_{MPP}$)과의 관계를 이용하였고 이는 pilot PV cell을 이용함으로써 가능하였다. 설계결과 MPPT control을 적용했을 때 부하가 큰 경우에도 대략 $V_{MPP}$ 전압을 부하에 공급함으로써 부하에 연결된 회로가 정상적으로 동작하는 것을 확인하였다. 제안된 회로는 TSMC 0.18um CMOS 공정으로 설계되었다.

• Current Photovoltaic Research
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• 제4권3호
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• pp.108-113
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• 2016

III-V compound semiconductor based thin film solar cells promise relatively higher power conversion efficiencies and better device reliability. In general, the thin film III-V solar cells are fabricated by an epitaxial lift-off process, which requires an $Al_xGa_{1-x}As$ ($x{\geq}0.8$) sacrificial layer and an inverted solar cell structure. However, the device performance of the inversely grown solar cell could be degraded due to the different internal diffusion conditions. In this study, InGaP/GaAs double-junction solar cells are inversely grown by MOCVD on GaAs (100) substrates. The thickness of the GaAs base layer is reduced to minimize the thermal budget during the growth. A wide band gap p-AlGaAs/n-InGaP tunnel junction structure is employed to connect the two subcells with minimal electrical loss. The solar cell structures are transferred on to thin metal films formed by Au electroplating. An AlAs layer with a thickness of 20 nm is used as a sacrificial layer, which is removed by a HF:Acetone (1:1) solution during the epitaxial lift-off process. As a result, the flexible InGaP/GaAs solar cell was fabricated successfully with an efficiency of 27.79% under AM1.5G illumination. The efficiency was kept at almost the same value after bending tests of 1,000 cycles with a radius of curvature of 10 mm.

• BMB Reports
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• 제45권8호
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• pp.482-487
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• 2012

To identify the novel inhibitors of endoplasmic reticulum stress-induced cell death, we performed a high throughput assay with a chemical library containing a total of 3,280 bioactive small molecules. Cyclosporine A and bromocriptine were identified as potent inhibitors of thapsigargiin-induced cell death (cut-off at $4{\sigma}$ standard score). However, U74389G, the potent inhibitor of lipid peroxidation had lower activity in inhibiting cell death. The inhibition effect of cyclosporine A and bromocriptine was specific for only thapsigargin-induced cell death. The mechanism of inhibition by these compounds was identified as modification of the expression of glucose regulated protein-78 (GRP-78/Bip) and inhibition of phosphorylation of p38 mitogen activated protein kinase (MAPK). However, these compounds did not inhibit the same events triggered by tunicamycin, which was in agreement with the cell survival data. We suggest that the induction of protective unfolded protein response by these compounds confers resistance to cell death. In summary, we identified compounds that may provide insights on cell death mechanisms stimulated by ER stress.

• 한국전기전자재료학회논문지
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• 제33권5호
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• pp.367-372
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• 2020

As packaging processes for atomic gyroscope vapor cells, the glass tube tip-off process, anodic bonding, and paste sealing have been widely studied. However, there are stability issues in the alkali metal which are caused by impurity elements and leakage during high-temperature processes. In this study, we investigated the applicability of a vapor cell low-temperature packaging process by depositing Au on a Pyrex cell in addition to forming an Au-Sn thin film on a cap to cover the cell, followed by laser irradiation of the Au/Au-Sn interface. The mechanism of the thin film bonding was evaluated by XRD, while the packaging reliability of an Ne gas-filled vapor cell was characterized by variation of plasma discharge behavior with time. Furthermore, we confirmed that the Rb alkaline metal inside the vapor cell showed no color change, indicating no oxidation occurred during the process.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.554-559
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• 1998

Equalizing the state of charge of cell that affects the charge/discharge quality and efficiency of the battery through the charge/discharge characteristic experiments of battery source, we develope the high efficiency charge/discharge system which would be used in serial HEV with the constant engine-generator output. For this, establishes the electrical model of Ni-MH battery appropriate to the high efficiency charge/discharge conditions. There is no model of Ni-MH cell, so we used Ni-Cd model and obtain the Ni-MH model through the experiment. A reason that each cell has the same charge/discharge property for applying the cell model to serial/parallel connected battery source extensively is needed. Therefore, in this paper, propose the Ni-MH charger/discharger has the equalization charging function and selectable cut-off function.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.91-93
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• 2008

A Buoyant Hybrid Power Generation System (BHPGS) described in this paper, is a conceptual approach to a hybrid solar-wind power generation in the near sea. The primary purpose of the BHPGS is given to improve utilization of solar cell modules. Main components of the BHPGS include a solar cell module, buoyant object, power generator, and support assembly including weight. Components such a generator controller, DC/AC converter, etc., are not configured in the current BHPGS because they can easily be purchased as a commercial-off-the-shelf product. In addition, some of the BHPGS applications are discussed.

• Journal of Plant Biology
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• 제27권4호
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• pp.233-239
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• 1984

Reproductives structures of Pachymeniopsis elliptica (Holmes) Yamade (Rhodophyta, Grateloupiaceae) are investigated. In female gametophyte the carpogonial branch and auxiliary cell are produced in separate accessory branch system, the primary ampullar filament originated from mid-cortical layer. After fertilization, auxiliary cell joined with connecting filament becomes a fusion cell by fusing with several neighboring ampullar cells. The fusion cell produces a gonimoblast initial. It divides into gonimoblast cells, which later convert to carposporangia. In male gametophyte superficial cortical cells of vegetative filament produce two spermatangial mother cells which cut off up to three spermatangia respectively. Tetrasporangial initials are formed from the 6th to 12th cells of the cortical layer in tetrasporophyte, and divided cruciately to form tetrasporangium. Some of the sporangia are, however, divided zonately.