• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.4B no.3
• /
• pp.108-113
• /
• 2004

This paper presents methods to improve performance of the power supply system in a NASA deep space explorer. In the Stirling engine driven reciprocating Brushless DC (BLDC) generator, the accurate position information of the prime mover is important to diagnose the performance of the engine and prevent distortion of the output power. Since sensors to detect the position are fragile and unreliable, and conventional sensorless techniques have drawbacks in the low speed region, a novel sensorless position detection technique for the prime mover has been proposed and verified. Another major issue of the generator for the spacecraft is power density maximization. The mass of the power system is important to the mass of the satellite. Therefore, the components of the spacecraft should be lightweight. Conventional rectification methods cannot achieve the maximum power possible due to non-optimal current waveforms. The optimal current waveform for maximizing power density and minimizing machine size and weight in a nonsinusoidal power supply system has been derived, incorporated in a control system, and verified by simulation work.

• Proceedings of the Korea Society of Environmental Biology Conference
• /
• 2003.11a
• /
• pp.12-15
• /
• 2003

The effects of the non-steroidal ecdysteroid agonist tebufenozide on larvae of C. faviplumus and C. riparius were tested in the laboratory. In the most treatments it reached a statistically significant difference from the control condition. As the concentration of tebufenozide was increased, a relatively larger proportion of the observed mortality was associated with the metamorphosis and molting process. Also, the larval mortality of the first larvae was higher than the fourth-instar larvae in C. riparius. In terms of development, the effects of tebufenozide were delayed growth stage in relatively lower concentration such as 10 $\mu\textrm{g}$/L treatments. Based on the mortality, the susceptibility followed the first-instar C. riparius > the fourth-instar C. flaviplumus > the fourth-instal C. riparius. The morphological effects showed that the first and second segments of body of exposed larvae with tebufenozide expanded slowly and not made a complete cephalothorax of pupae during long times or days. And the head capsule slipped down and forward, revealing a fragile and non-pigmented, unsclerotized new head capsule. There was obvious significant difference in the male/female ratio in contaminated fourth larvae of C. riparius. Also, due to the different emergence periods of male/female in low insecticide concentrations, mating chances or opportunities of insects should be decreased. Accordingly, ecological strategies for keeping of sustainable populations should be disrupted.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.15 no.2
• /
• pp.113-122
• /
• 2005

In this paper, we propose a multi-watermarking algorithm to satisfy two purposes: fragility against malicious attacks and robustness against non-malicious attacks. The algorithm can be used for image authentication using coefficients of Discrete Wavelet Transform(DWT). In the proposed method, watermarks are generated by combining binary image with some features extracted from the subband LL3, and then they are embedded into both the spatial and frequency domain. That is, on the spatial domain they are embedded into the Least Significant Bit(LSB) of all pixels of image blocks, and on the frequency domain the coefficients of the subband LH2 and HL2 are adjusted according to the watermarks. Thus the algorithm not only resists malicious attack but also permits non-malicious attacks such as blurring, sharpening, and JPEG compression.

• Lettere Italiane
• /
• no.36
• /
• pp.73-97
• /
• 2012

Danubio è un 'diario di viaggio' dalle sorgenti del fiume fino al Mare Nero, attraverso città importantissime o paesi, ampi paesaggi, popoli, costumi, letterature e lingue diverse. Un itinerario fra romanzo e saggio che racconta la cultura come esperienza esistenziale e ricostruisce a mosaico le civiltà di Mitteleuropa rintracciandone il profilo nei segni della grande storia e nelle effimere tracce della vita quotidiana. L'idea di Mitteleuropa nasce a meta dell'Ottocento per indicare un spazio politico e soprattutto economico egemonizzato dai tedeschi e dagli ungheresi, che piu tardi diventa il simbolo di programmi nazionalisti tedeschi e che poi diventa una dimensione sovranazionale, qualcoca di comune e sottostante a tutte le diverse nazionalità e culture di tante realtà diverse. La Mitteleuropa 'hinternazionale', oggi idealizzata quale armonia di popoli diversi, è stata una realtà dell'impero absburgico, nella sua ultima stagione, una tolleranzte convivenza comprensibiilmente rimpianta dopo la sua fine, anche per il confronto con la barbarie totalitaria che le è succeduta, fra le due guerre mondiali, nello spazio danubiano. L'arte absburgica di governo non vuole imporre una rigida unità ai vari popoli, bensi lasciarli sussistere e convivere nella loro eterogeneità. Secondo Claudio Magris, il Danubio è il simbolo della frontiera, perché il Danubio è un fiume che passa attraverso tante frontiere, è quindi simbolo della necessità e della difficoltà di attraversare frontiere, non soltanto nazionali, politiche, sociali, ma anche psicologiche, culturali, religiose. La nostra identità è sempre fragile e noi dobbiamo accettare questa fragilità, poiché mutiamo nel tempo. L'identità fatta di mescolanze, di sottrazioni e di elisioni non fosse soltanto il destino degli epigoni danubiani, bensì una condizione storica generale, l'esistenza di ogni individuo. Magris dice che siccome nessun popolo, nessuna cultra come nessun individuo sono privi di colpe storiche, rendersi impietosamente conto dei difetti e delle oscurità di tutti, e di se stessi, può essere una proficua premessa di convivenza civile e tollerante. Magris dice che la letteratura è di perse stessa una frontiera, una soglia, una zona sul limitare e insegna a varcare i limiti, ma consiste nel tracciare dei limiti, senza i quali non puo esistere e nemmeno la tensione a superarli per raggiungere qualcosa di piu alto e di piú umano.

• Corrosion Science and Technology
• /
• v.15 no.3
• /
• pp.125-128
• /
• 2016

The ASTM T92 steel was corroded at $600^{\circ}C$ and $800^{\circ}C$ at 1 atm of $N_2/3.1%H_2O/2.42%H_2S-mixed$ gas. The formed scales were thick and fragile. They consisted primarily of the outer FeS scale and the inner (FeS, $FeCr_2S_4$)-mixed scale containing a small amount of the $Cr_2O_3$ scale. This indicated that corrosion occurred mainly via sulfidation rather than oxidation due to the $H_2S$ gas. Since FeS was present throughout the whole scale, T92 steel was non-protective, displaying high corrosion rates.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.1
• /
• pp.165-171
• /
• 2013

The aim of the present study was to analyze the expression of FHIT and WWOX in nasopharyngeal carcinoma (NPC) and correlations with clinical pathologic features. mRNA expression of the FHIT and WWOX was assessed by real-time fluorescent relatively quantitative PCR in 61 NPC tissues and 45 non-cancerous nasopharyngeal tissues. As a result, mRNA expression levels of both FHIT and WWOX were significantly lower in NPC patients than in control samples (P=0.049 and 0.045, respectively). Moreover, the mRNA expression of both had an inverse relation with larger invasive range (P=0.035 and 0.048, respectively), poor histologic differentiation (P=0.012 and 0.016) and advanced clinical stage (P=0.026 and 0.038). Consistency was found between expression of FHIT and WWOX in the same NPC tissues (r=0.681, P=0.00). In conclusion, synergy between FHIT and WWOX may exist in the development of NPC so that the two factors may be considered as important genetic markers. Detecting the expression of FHIT and WWOX should provide clinically significant information relevatn to tumor diagnosis, progression and treatment modalities for NPC.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.5 no.12
• /
• pp.2340-2354
• /
• 2011

A new and secure image steganographic scheme based on nonuniform discrete Fourier transform (NDFT) is proposed in this paper. First, the chaotic system is introduced to select embedding points randomly in NDFT domain suitable range, and NDFT is implemented on every non-overlapping block of eight consecutive pixels. Second, the secret messages are scrambled by chaotic systems, and embedded into frequency coefficients by quantization method. The stego-image is obtained by inverse NDFT (INDFT). Besides, in order to discriminate tampers, the low frequency wavelet coefficients of 7 most significant bits (MSBs) of the stego-image are converted into the binary sequence after nonuniform scalar quantization. Then the obtained binary sequence is scrambled by the chaotic systems, and embedded into the least significant bit (LSB) of the stego-image. Finally, the watermarked stego-image can be obtained by a new improved LSB steganographic method. The embedded secret messages can be extracted from the watermarked stego-image without the original cover image. Experimental results show the validity of the proposed scheme, and dual statistics attacks are also conducted to indicate the security.

• Journal of the Korean institute of surface engineering
• /
• v.51 no.6
• /
• pp.354-359
• /
• 2018

NaCl-induced hot corrosion behavior of ASTM T22 (Fe-2.25Cr-1Mo), T91 (Fe-9Cr-1Mo), T92 (Fe-9Cr-1.8W-0.5Mo), 347HFG (Fe-18-Cr-11Ni), and 310H (Fe-25Cr-19Ni) steels was studied after spraying NaCl on the surface. During corrosion at $600-800^{\circ}C$ for 50-100 h, thick, non-adherent, fragile, somewhat porous oxide scales formed. All the alloys corroded fast with large weight gains owing to fast scaling and destruction of protective oxide scales. Corrosion rates increased progressively as the corrosion temperature and time increased. Corrosion resistance increased in the order of T22, T91, T92, 347HFG, and 310H, suggesting that the alloying elements of Cr, Ni, and W beneficially improved the corrosion resistance of steels. Basically, Fe oxidized to $Fe_2O_3$, and Cr oxidized to $Cr_2O_3$, some of which further reacted with FeO to form $FeCr_2O_4$ or with NiO to form $NiCr_2O_4$.

• Asian-Australasian Journal of Animal Sciences
• /
• v.32 no.3
• /
• pp.309-319
• /
• 2019

Phytochemicals which exist in various plants and fungi are non-nutritive compounds that exert numerous beneficial bioactive actions for animals. In recent years following the restriction of antibiotics, phytochemicals have been regarded as a primal selection when dealing with the challenges during the producing process in the poultry industry. The selected fast-growing broiler breed was more fragile when confronting the stressors in their growing environments. The disruption of oxidative balance that impairs the production performance in birds may somehow be linked to the immune system since oxidative stress and inflammatory damage are multi-stage processes. This review firstly discusses the individual influence of oxidative stress and inflammation on the poultry industry. Next, studies related to the application of phytochemicals or botanical compounds with the significance of their antioxidant and immunomodulatory abilities are reviewed. Furthermore, we bring up nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and nuclear factor kappa B ($NF-{\kappa}B$) for they are respectively the key transcription factors involved in oxidative stress and inflammation for elucidating the underlying signal transduction pathways. Finally, by the discussion about several reports using phytochemicals to regulate these transcription factors leading to the improvement of oxidative status, heme oxygenase-1 gene is found crucial for Nrf2-mediated $NF-{\kappa}B$ inhibition.

• English & American cultural studies
• /
• v.18 no.2
• /
• pp.51-78
• /
• 2018

To put it simply, thing theory is a study of meaningful capacities of materiality. Although T. S. Eliot regarded pathetic fallacy as the bad example of objective correlatives in his modernism poetry theory, it is clear that many objects in literary works reflect diverse human desires. Among many, Victorian sensation novels are the most distinct genre where the various paraphernalia in them indicate the distorted and exaggerated greed of the industrial revolution era. Whereas the male protagonists are usually related with the norms objects of authority such as portrait and locket, the female characters' connection with cosmetics and white dress shows their oppressed and fragile position in the patriarchal and hierarchical society. In the (post)modern society, the ambiguity of things has grown rapidly due to the increasing discrepancy between objects and things. In special, the new journalism and the psychological realism novels often reveal the post-truth phenomenon because consumerized audience depend more upon the attraction and affect than the mere evidence and facts. For the individual, according to object relations theory, these alternative facts are rather internalized into their mind as the internal object when they are motivated by the non/contact with primary caregivers in their childhood. The dominant material imagery in (post)modern fiction becomes the site of resistance because of their reconstructed and extended meaning. The object relations theory and thing theory can be effectively used to uncover the complicated meanings of desired objects by using the human-object's meaningful relations and early mental images that are secretly alive still in the present.