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Place recognition is a method for determining whether a robot has previously visited the place it currently observes, thus helping the robot correct its accumulated position error. Ultimately, the robot will travel long distances more accurately. Conventional image-based place recognition uses features extracted from a bag-of-visual-words (BoVW) scheme or pre-trained deep neural network. However, the BoVW scheme does not cope well with environmental changes, and the pre-trained deep neural network is disadvantageous in that its computation time is high. Therefore, this paper proposes a novel place recognition scheme using an illumination-compensated image-based deep convolutional autoencoder (ICCAE) feature. Instead of reconstructing the raw image, the autoencoder designed to extract ICCAE features is trained to reconstruct the image, whose illumination component is compensated in the logarithm frequency domain. As a result, we can extract the ICCAE features based on a convolution layer that is robust to illumination and environmental changes. Additionally, ICCAE features can perform faster feature matching than the features extracted from existing deep networks. To evaluate the performance of ICCAE feature-based place recognition, experiments were conducted using a public dataset that includes various conditions.

In image-based global localization, a robot pose is estimated through image association when the robot revisits a previously visited location on a map. Image association is typically performed using high-level local features such as scale invariant feature transform (SIFT) and speeded up robust feature (SURF). However, these methods suffer from false-positive association and high computational load to reject outliers. In this study, we introduce a novel global localization method based on the proposed low-frequency image-based descriptor (LFID) and laser range data. The image is first processed by reducing the range of luminance in the frequency domain. Visual features are then extracted from the processed image through a kernel window. These visual features are described as binary representation for fast association. Because this binary representation includes a spatial distribution of features, it can minimize false-positive association. Nevertheless, false-positive association could occur when scenes appear to be similar from different viewpoints. To address this problem, this study adopts a laser rangefinder to validate the similarity of the place and reject false-positives from the scene recognition. Experimental results confirm the effectiveness of the proposed scheme in actual indoor environments.

Convolutional-neural-network (CNN)-based methods are continuously used in various industries with the rapid development of deep learning technologies. However, an inference efficiency problem was reported in applications that require real-time performance, such as a mobile device. It is important to design a lightweight network that can be used in general-purpose environments such as mobile environments and GPU environments. In this study, we propose a lightweight network efficient shot detector (ESDet) based on deep training with small parameters. The feature extraction process was performed using depthwise and pointwise convolution to minimize the computational complexity of the proposed network. The subsequent layer was formed in a feature pyramid structure to ensure that the extracted features were robust to multiscale objects. The network was trained by defining a prior box optimized for the data set of each feature scale. We defined an ESDet-baseline with optimal parameters through experiments and expanded it by gradually increasing the input resolution for detection accuracy. ESDet training and evaluation was performed using the PASCAL VOC and MS COCO2017 Dataset. Moreover, the average precision (AP) evaluation index was used for quantitative evaluation of detection performance. Finally, superior detection efficiency was demonstrated through the experiment compared to the conventional detection method.

The Weondong skarn deposit primarily consists of grandite (andradite-grossular) garnets, which exhibit poikilitic/intergrowth textures and compositional zoning in metasomatism. The garnets can be classified into three main types based on their textural characteristics and rare earth element (REE) concentrations: (1) exoskarn garnet near quartz porphyry with a poikilitic texture and oscillatory zoning (core: And 31–50 , rim: And 54–63 ) (T1 garnet), (2) exoskarn garnet near quartz porphyry with intergrowths (core: And 55–83 , mantle: And 55–59 , rim: And 77–97 ) and poikilitic textures (T2 garnet), and (3) vein-hosted garnet with reverse zoning (core: And 70–96 , rim: And 31–36 ) and epitaxial growth on distinct cores (T3 garnet). The textural features of the garnets are considered to have been caused by periodic fluctuations. The chondrite-normalized REE patterns of the garnet types show that the Al-rich garnets are HREE-enriched and formed at equilibrium with slow growth rates according to the kinetics of the garnet's growth. In contrast, Fe-rich garnets are slightly LREE-enriched and HREE-depleted. In terms of the kinetics of the garnet's growth, the Fe-rich garnets grew rapidly from externally derived fluids during infiltration metasomatism. The enriched W contents in the grandite garnets also indicate the type of growth mechanism, the infiltration process, and a specific skarn environment (such as advective metasomatism). Furthermore, each textural type of garnet was influenced differently by fluid/rock interactions, the magnitude of the fluid flow and the fluid compositions in the skarn system. Consequently, periodic fluid fluctuation in the skarn system affected the morphology and composition of individual garnet grains. Thus, the geochemical features of the grandite garnet from the Weondong polymetallic deposit provide key information to understand the evolution of the skarn deposit and its metasomatic history.

본 연구는 원자력 중대 사고 시, 환경에 유출된 방사성 세슘의 확산을 억제하기 위해 충북 영동지역 일라이트의 활용 가능성을 평가하였다. 영동 일라이트는 운모질 편암의 열수변질 작용에 의해 형성되었으며, 주요 구성 광물은 석영, 장석, 일라이트이다. 저농도 세슘 용액을 사용한 회분식 흡착실험 결과, 영동 일라이트의 흡착 분배 계수(Kd)는 약 4,200 L kg-1으로 다른 점토 광물에 비해 비교적 높은 값을 가지며, 이는 일라이트에 존재하는 풍화된 모서리면(FES)의 영향으로 판단된다. 영동 일라이트와 세슘의 흡착등온선은 비선형 흡착 특성을 나타내며 단일 표면 한계 흡착 능력이 250,000 μg kg-1으로 우수한 흡착능을 보여주어 방사성 세슘 흡착제로서의 사용 가능성을 입증하였다. 이러한 결과는 추후 방사능 누출 사고 등의 긴급 상황 발생 시, 영동 지역 일라이트를 오염 확산 방지 및 정화작업에 사용하기 위한 평가 자료로 활용될 것으로 기대된다.

In this study, a novel and rapid vision-based sensing strategy is developed exclusively for dynamic wave height measurement of tuned liquid column dampers (TLCDs). The image processing algorithm of the vision-based sensing method simply counts white pixels in a binary image and thus expedites the vision-based wave height measurement. In addition to the experimental achievement, a practical methodology of dynamic characterization for the TLCDs is proposed combining linearized equations for the TLCDs and experimental data measured. An experimental characterization of dynamic behaviors and damping properties of the TLCDs is undertaken utilizing the vision-based sensing developed.

To separate the CM and DM noise in the EMI generated in various electrical electronic systems, passiveand active separators have been researched. These separators are an important part of an effective active EMI-filter.The passive separator has some advantages, in that it is easy to realize at a low price and its structure is very simple.However, its major drawback is that its accurate inductor realization and accurate core selection are very difficult. The active separator is smaller in size and more accurate, but its main drawback is that an op-amp which has a broadband frequency response is necessary, its cost is high, and a DC power circuit is required. This paper compares thecharacteristics of EMI filters which apply the existing passive separator and proposed active separator. It was concluded that an active separator is needed for expensive and accurate equipment, whereas a passive separator issufficient for inexpensive and general purpose EMI filters. Keywords : active noise separator, passive noise separator, CM, DM, EMI-filter

The Permian–Triassic high pressure metamorphism and potassic magmatism in central Korea attest to the extension of the Dabie-Sulu collision belt in central-eastern China towards the Korean Peninsula and possibly the Japanese Islands. We present major and trace element and Sr–Nd isotope data for a ca. 230 Ma monzodiorite pluton emplaced in the Goesan area, central Okcheon belt, Korea. This pluton shows geochemical features comparable with those of the coeval monzonite–syenite–gabbro–mangerite suite documented recently in the Gyeonggi massif. The metaluminous and alkali–calcic signatures of the Goesan intrusives correspond to the Caledonian-type post-orogenic granitoids. The K2O/Na2O ratios of all analyzed samples are greater than 1, and are not correlative with their SiO2 contents. The enrichment of both large-ion-lithophile elements and highly compatible elements in the Goesan pluton is probably indicative of metasomatized mantle origin. The elemental fractionation in the source region must have occurred in the distant past, possibly the Paleoproterozoic, to generate significantly negative eNd(t) values (< –16). Chondrite-normalized rare earth element patterns as well as Rb/Sr and Ba/Rb ranges suggest that the source consists of amphibole-bearing rocks. Progressive decreases in negative Eu anomaly and Ba, Sr, Ni, Cr and V contents with increasing SiO2 contents reflect an important role of plagioclase, biotite and hornblende for the fractionation process. Zr is undersaturated in the potassic, metaluminous melt. The initial Sr–Nd isotopic compositions of the samples are correlated with their SiO2 contents, substantiating a role of crustal assimilation during the magmatic differentiation. The Sr–Nd elemental and isotopic modeling suggests that the Goesan pluton was initially slightly heterogeneous in its isotopic composition, and underwent concurrent assimilation and fractional crystallization. The occurrence of the Goesan pluton provides further evidence corroborating the amalgamation of allochthonous terranes within the Okcheon belt during the Permian–Triassic collisional orogeny. 韓国中央Okcheon(沃川)帯のGoesan(槐山)モンゾ閃緑岩の成因に関する地球化学的及びSr-Nd同位体的制約 抄録 要旨 韓国中央部のペルム紀-三畳紀高圧変成作用とカリウム系列火成作用は,中国中央東部の大別-蘇魯衝突帯が韓半島から恐らく日本列島まで続くことの証左である.本論では韓国沃川帯,槐山地域に定置した230 Maのモンゾ閃緑岩体の主要・微量元素及びSr-Nd同位体データを報告する.本深成岩体は近年Gyeonggi (京畿)地塊において記載された同時代のモンゾニ岩-閃長岩-ガブロ-マンゲライト岩類に地球化学的に対比できる.メタアルミナ及びアルカリ-カルク質の槐山貫入岩体はカレドニア型の後造山期花崗岩類に相当する.K2O/Na2O比は1を超え,SiO2含有量とは相関しない.槐山深成岩体のLIL元素と不適合元素の濃集は恐らくメタソマティズムを受けたマントル起源であることを示す.起源物質は古い地質時代に元素分別を受けたために,顕著な負のeNd(t)値(< -16)を示す.コンドライトで規格化した希土類元素パターンやRb/Sr比及びBa/Rb比は起源物質に角閃石が含まれることを示唆する.SiO2が増えるにつれてEuの負異常やBa,Sr,Ni,Cr,V含有量が減少することは,主として斜長石,黒雲母,普通角閃石の分別が起きたことを反映している.Zrは高カリウム,メタアルミナ質のメルト中では不飽和である.Sr-Nd同位体の初期値はSiO2と相関を示し,マグマの分化作用に地殻の同化が関わっていることを裏付ける.Sr-Nd元素及び同位体モデルは,槐山深成岩体が初期には同位体的にやや不均質であり,同化と結晶分別を同時に経験したことを示唆する.槐山深成岩体はペルム紀-三畳紀の衝突造山運動の間に沃川帯において起きた異地性テレーンの集合を証拠立てるものである.

Lactulose is a synthetic by-product of the isomerization of lactose to disaccharide galactosyl β-(1 → 4) fructose, and is widely applied as an oral therapeutic and laxative. As a prebiotic, lactulose is thought to control gastrointestinal diseases associated with weaning both in humans and animals. This study focuses on the effect of lactulose as a prebiotic supplement in modulating the microbial community composition and diversity in 30 piglets. The swine faecal microbiome was investigated using 16S rRNA gene barcoded-pyrosequencing before and after lactulose administration for 2 weeks. Major shifts in bacterial composition were detected from the phylum to species level. An increased abundance of Firmicutes phylum and lower abundance of the Bacteroidetes phylum were observed in pigs fed with lactulose compared with the control group. Interestingly, there was a negative relationship between lactulose administration and abundance of the genus Escherichia . In addition, a marked increase in the abundance of Lactobacillus reuteri (1.15–6.28%) was observed in the lactulose group. The canonical loading plot showed that three genera, Prevotella , Subdoligranulum , and Clostridium , were highly discriminating genera that explain the separation of swine faecal microbiota by lactulose administration. Overall, our results showed that lactulose administration could effectively increase diversity and create a distinct microbial community in weaned piglets, which is believed to be important and beneficial to health and performance.

X-Ray phase contrast imaging (PCI) is being developed as an alternative to overcome the poor contrast sensitivity of existing attenuation imaging techniques. The “phase sensitivity” can be achieved using a number of phase-enhancing geometries such as free space propagation, grating interferometry and edge illumination (also known as coded aperture) technique. The enhanced contrast in the projected intensities (that combine absorption and phase effect) can vary by object shape, size and its material properties as well as the particular PCI method used. We show a comparison of this signal enhancement for both FSP and coded aperture (CA) PCI. Our data shows that the phase enhancement is significantly higher for CA in comparison to FSP. Our preliminary results indicate that the enhanced phase effect decreases in all PCI techniques with increasing background thickness. Investigations involving signal location and background tissue thickness dependent signal enhancement (and/or loss of this signal) are very important in determining the true benefit of PCI methods in a practical application involving thick organs like breast imaging.

Although our understanding of probiotics is increasing, basic information regarding their effect on the composition of the gut microbiome is scarce. The purpose of this study was to characterize the fecal microbiota of weaned piglets before and after probiotic intervention. The probiotic bacterium Enterococcus faecium NCIMB 11181 was administered to pigs for 2 weeks and fecal bacterial diversity using 16S rRNA gene pyrosequencing was analyzed. A more stable bacterial community, as indicated by increased bacterial diversity and richness, was observed after administration of the probiotic, compared with the control group. Regardless of the diet, Firmicutes and Bacteroidetes were found to be the dominant bacterial phyla in the pigs; however, inhibition of Proteobacteria was clearly evident in the probiotic group. In addition, the probiotic-fed group featured elevated levels of Lactobacillus , Enterococcus , Oscillibacter , Succinivibro , and Clostridium genera and decreased levels of Escherichia and Dialister genera , compared with the control group. This study demonstrated that the probiotic E. faecium NCIMB 11181 modulates the fecal microbiota of weaned piglets. This modulation is characterized by an increase in other bacterial species including L. johnsonii , L. fermentum , and L. kimchii and several Clostridium spp., which might be beneficial to the health of weaned piglets.

In recent years, research on collaborative filtering-based recommendation systems emphasized the accuracy of rating predictions, and this has led to an increase in computation time. As a result, such systems have divergeded from the original purpose of making quick recommendations. In this paper, we propose a recommendation algorithm that uses a Preference Difference Metric to reduce the computation time and to maintain adequate performance. The system recommends items according to their preference classification.

An abdominal aorta aneurysm (AAA) is a disease that aortic vessel inflates abnormally. The aorta blows up continuously, which may lead to the rupture of the aorta. The mortality of rupturing the aorta is between 75 and 90% to properly treat this disease, we need to accurate measure about variation of AAA size. our team performed that AAA is reconstructed as three dimensional (3D) images by computer tomography (CT), and analyzed the elements of inflation through a geometric parameter measurement . Subjects (seven males) who undergo an AAA are enrolled for the analysis. The authors used CT images as a primary source, and obtained secondary CT images 12 months later. By means of these data, the authors constructed 3D images of AAA and performed examinations using a geometric analysis that calculates geometric parameter such as the tortuosity, diameter, saccular and so on based on volume, area of the segmented region of the CT slices that is set up by the centroids and 8 points around it. The result of the severity biomechanical factor shows increased AAA tortuosity ratio (4.9%), AAA diameter expansion ratio [cm/year] (6.8%), AAA total diameter ratio (4.7%), AAA saccular ratio (2.4%) than 12-month before. Through these results, We can plan to endovascular repair surgery to undergoing AAA patients and possible diagnosis estimation of AAA.

Wrist joints consist of irregularly shaped carpal bones and other complicated structures. Thus, evaluatingthe motion of a wrist joint is a challenging task. In this study, we used an infrared camera to perform a kinematicanalysis of a dart-throwing motion. We measured the difference between the movement of a normal wrist and con-strained wrist (wrist with a wrist glove) in the dart-throwing motion with thirty six healthy participants. We measuredthe ulna flexion - radial extension motion using the attached passive marker and analyzed it using Polygon softwareand SPSS. The pitch and yaw motions with a glove was bigger than the ones without a glove by 20 and 15 degrees,respectively. On the other hand, the roll motion without a glove was bigger than the one with a glove by 7 degree.Wilcoxon signed rank test (p < 0.05) confirmed that there are significant differences between the motion with andwithout a glove. It was found that the magnitude of the pitch and yaw motion with a constrained wrist joint towardradial extension in dart-throwing motion is smaller than the one with a normal wrist joint. However, a normal wristjoint showed a bigger movement in the roll direction.Key words: Wrist joint, Dart -throwing motion, Infrared camera

Photon counting spectral detectors are being investigated to allow better discrimination of multiple materials by collecting spectral data for every detector pixel. The process of material decomposition or discrimination starts with an accurate estimation of energy dependent attenuation of the composite object. Photoelectric effect and Compton scattering are two important constituents of the attenuation. Compton scattering while results in a loss of primary photon, also results in an increase in photon counts in the lower ene 1 rgy bins via multiple orders of scatter. This contribution to each energy bin may change with material properties, thickness and x-ray energies. There has been little investigation into the effect of this increase in counts at lower energies due to presence of these Compton scattered photons using photon counting detectors. Our investigations show that it is important to account for this effect in spectral decomposition problems.

We present a revised alkali fusion method for the determination of trace elements in geological samples. Our procedure is based on simple acid digestion of powdered low-dilution (flux : sample ≈ 2 : 1) glass beads where large sample dilution demanded by high total dissolved solids, a main drawback of conventional alkali fusion, could be circumvented. Three geological reference materials (G-3 granite, GSP-2 granodiorite and SGD-1a gabbro) decomposed by this technique and routine tabletop acid digestion were analysed for thirty trace elements using a quadrupole ICP-MS. Results by conventional acid digestion distinctly showed poor recoveries of Zr, Hf and rare earth elements due to incomplete dissolution of resistant minerals. On the other hand, results obtained by our method were in reasonable agreement with reference data for most analytes, indicating that refractory minerals were efficiently dissolved and volatile loss was insignificant. Nous presentons une methode revisee de fusion alcaline pour la determination des elements traces dans des echantillons geologiques. Notre methode est basee sur la digestion acide simple a faible dilution (flux : echantillon ≈ 2 : 1) de poudres de perles de verre, methode dans laquelle la dilution de larges echantillons exigee par de forts totaux de solides dissous, inconvenient principal de la fusion alcaline conventionnelle, pourrait etre contournee. Trois materiaux geologiques de reference (granite G-3, granodiorite GSP-2 et gabbro SGD-1a) decompose par cette technique et par celle de digestion acide classique ont ete analyses pour 30 elements traces a l'aide d'un ICP-MS quadripolaire. Les resultats obtenus en utilisant la digestion acide classique ont nettement montre des faibles recouvrements de Zr, Hf et des terres rares en raison de la dissolution incomplete des mineraux resistants. D'autre part, les resultats obtenus par notre methode sont en accord raisonnable avec les donnees de reference pour la plupart des elements analyses, ce qui indique que les mineraux refractaires ont ete dissous efficacement et que la perte en volatils a ete negligeable.

To generate the walking path of a humanoid robot in an unknown environment, the shapes of obstacles around the robot should be detected accurately. However, doing so incurs a very large computational cost. Therefore this study proposes a method to classify the obstacle shape into three types: a shape small enough for the robot to go over, a shape planar enough for the robot foot to make contact with, and an uncertain shape that must be avoided by the robot. To classify the obstacle shape, first, the range and the number of the obstacles is detected. If an obstacle can make contact with the robot foot, the shape of an obstacle is accurately derived. If an obstacle has uncertain shape or small size, the shape of an obstacle is not detected to minimize the computational load. Experimental results show that the proposed algorithm efficiently classifies the shapes of obstacles around the robot in real time with low computational load.

Depth sensors have been increasingly used for object recognition in recent years. However, it is very challenging for simultaneous localization and mapping (SLAM) to make use of the forward scenes from a depth sensor. To this end, we introduce the object recognition framework for SLAM in indoor environments based on the extraction of an object-level descriptor. The proposed object-level descriptor can be obtained based on the surface appearances acquired from a depth sensor without any training. To express the surface normal distribution, a well-known descriptor, fast point feature histogram (FPFH), with a small sampling radius is used to define basic shape elements of a plane, a cylinder and a sphere. The object-level descriptor to recognize the objects can be obtained using these shape elements. Several experiments on arbitrary objects on the floor show the proposed scheme is useful in object recognition and generation of the feature map.

A trace element composition of rock samples is difficult to determine when they contain refractory minerals that are hardly dissolved with conventional acid digestion techniques. Fused glass beads of rock samples could be an adequate target to circumvent this problem. We here report inductively coupled plasma-mass spectrometry (ICP-MS) results for geological reference materials (GRMs) prepared to normal- (sample/flux = 1:5) and low-dilution (sample/flux = 1:2) glass beads by using Nd:YAG UV 213-nm laser ablation system. Concentrations of 24 trace elements (Ba, Hf, Nb, Rb, Sr, Ta, Th, U, Y, Zr, and 14 rare earth elements (REEs)) were analyzed for three USGS GRMs (G-3 granite, AGV-2 andesite, and BHVO-2 basalt). Each analysis for the GRM beads was performed as spot (ca. 55 μm diameter) analysis with 120-s ablation time. The depth-to-diameter ratio of the laser spot was low (

X-ray phase contrast imaging has been investigated during the last two decades for potential benefits in soft tissue imaging. Long imaging time, high radiation dose and general measurement complexity involving motion of x-ray optical components have prevented the clinical translation of these methods. In all existing popular phase contrast imaging methods, multiple measurements per projection angle involving motion of optical components are required to achieve quantitatively accurate estimation of absorption, phase and differential phase. Recently we proposed an algorithmic approach to use spectral detection data in a phase contrast imaging setup to obtain absorption, phase and differential phase in a single-step. Our generic approach has been shown via simulations in all three types of phase contrast imaging: propagation, coded aperture and grating interferometry. While other groups have used spectral detector in phase contrast imaging setups, our proposed method is unique in outlining an approach to use this spectral data to simplify phase contrast imaging. In this abstract we show the first experimental proof of our single-shot phase retrieval using a Medipix3 photon counting detector in an edge illumination aperture (also referred to as coded aperture) phase contrast set up as well as for a free space propagation setup. Our preliminary results validate our new transport equation for edge illumination PCI and our spectral phase retrieval algorithm for both PCI methods being investigated. Comparison with simulations also point to excellent performance of Medipix3 built-in charge sharing correction mechanism.

This paper proposes a method to extract accurate plane of an object in unstructured environment for a humanoid robot by using a laser scanner. By panning and tilting 2D laser scanner installed on the head of a humanoid robot, 3D depth map of unstructured environment is generated. After generating the 3D depth map around a robot, the proposed plane extraction method is applied to the 3D depth map. By using the hierarchical clustering method, points on the same plane are extracted from the point cloud in the 3D depth map. After segmenting the plane from the point cloud, dimensions of the planes are calculated. The accuracy of the extracted plane is evaluated with experimental results, which show the effectiveness of the proposed method to extract planes around a humanoid robot in unstructured environment.

Ophiolites, the remnants of ancient oceanic lithosphere, have been described from collisional sutures of various ages with only few examples from Archean terranes. Here we report the discovery of a Neoarchean ophiolite suite from the southern margin of the Dharwar Craton in India, tectonically intercalated within a Neoproterozoic suture zone. The metamorphosed and variably dismembered ophiolite suite, exposed around Devanur, comprises altered ultramafic units, websterite, gabbros, mafic dykes, amphibolites, trondhjemites and pegmatites associated with ferruginous metachert. Structural and petrographic studies indicate that the rocks represent a highly sheared and metamorphosed suite emplaced as a thrust sheet. The major and trace element geochemistry of the mafic dykes indicate derivation from basaltic–andesitic magmas with tholeiitic to calc-alkaline characteristics. The rocks display negative Nb anomalies with enrichment of LILE (K, Rb, Ba, Th) and depletion in HFSE (Ti, Nb, Hf, Tb). The tectonic discrimination of these rocks based on various geochemical plots suggests that they were generated in a suprasubduction zone setting. We present new SHRIMP zircon U–Pb data for two trondhjemite samples from this complex, which yield 238U–206Pb ages of 2528 ± 61 and 2545 ± 56 Ma. The Neoarchean age from the trondhjemites obtained in our study is closely comparable to similar ages obtained in recent studies from magmatic zircons in charnockites and orthogneisses in the area. The suprasubduction zone assemblages and arc magmas suggest a Neoarchean ocean closure along the southern margin of the Dharwar Craton.

Open beaker digestion method is routinely used as the sample preparation technique for trace element determination of rock samples by inductively coupled plasma mass spectrometry, With this method, however, dissolution of Zr and Hf is not always guaranteed especially when the samples contain refractory minerals. In this study, glass bead digestion technique was compared with conventional open beaker digestion technique for the sample preparation of three USGS rock standards such as AGV-2, BHVO-2, and G-3. Thirty trace elements including rare earth elements were analysed by ICP-MS and ICP-AES. There were no clear differences in analytical results for the AGV-2 and BHVO-2 standards between the two techniques, but Zr, Hf, Y, and middle- to heavy- rare earth element concentrations of the G-3 standard prepared by open beaker digestion technique were significantly lower than the recommended values. This can be attributed to the presence of refractory mineral zircon. On the contrary, all the analytical results of the G-3 standard prepared by glass bead digestion technique were in good agreement with the recommended values, indicating complete dissolution of zircon. The analytical results show that the volatile elements such as Pb and Zn were not lost during the preparation of glass bead. Low dilution glass bead digestion technique described here will be very helpful to enhance precision and accuracy of trace element analysis for geological samples containing refractory minerals.

The proposed converter has easy device selection for high step-up and high power applications since boost half bridge and voltage doubler cells are connected, respectively, in parallel and series in order to increase output power and voltage. Especially, optimized design of high frequency transformers is possible owing to reduced turn ratio and eliminated dc offset, and distributed power through three cores is beneficial to low profile and thermal distribution. The proposed converter does not necessitate start-up circuit and additional clamp circuit due to the use of whole duty range between 0 and 1 and is suitable for applications with wide input voltage range. Also, high efficiency can be achieved since ZVS turn on of switches are achieved in wide duty cycle range and ZCS turn on and off of diodes are achieved. The proposed converter was validated through 5 kW prototype.

Among the common minerals of the spinel peridotites, clinopyroxene is the main carrier of trace elements and serves as a tracer of geological mantle processes. The trace element composition of clinopyroxenes on a thin section 30 μm thick was measured using LA-ICP-MS. The repeatability of thin section analysis was better than 3% at the 2 sigma level. When using a 213 nm laser with a 55 μm beam size, optimal analytical conditions for the LA-ICP-MS were determined to be a 55% energy level (9 J/cm2) and 10 Hz repetition rate, giving a penetration speed of clinopyroxene of 0.17 μm/pulse. Overall, the LA-ICP-MS technique can be used to determine the trace element composition of clinopyroxenes on thin sections with reasonable precision, accuracy, and limit of detection.

The primary purpose of this study was to analyze the motion of the scaphoid, capitate, and lunate during dart-throwing motion by three-dimensional modeling. Five series of CT images of five normal right wrists were acquired from five motion steps from radial extension to ulnar flexion in the dart-throwing motion plane. Segmentation and three-dimensional modeling of bones from CT images was performed using Analyze. Distances among centroids of the scaphoid, capitate and lunate and angles between principal axes of three carpal bones were calculated to analyze the motion by using MATLAB. As the wrist motion changed from radial extension to ulnar flexion, the distance between two adjacent bones decreased. The scaphoid and lunate rotated less than the capitates during dart-throwing motion. This study reports the Three-dimensional in vivo measurement of carpal motion using CT images.

The characterstics of absorption and accumulation of inorganic germanium in Panax ginseng C. A. Meyer were examined. In 4-year-old P. ginseng, the germanium content of the field soil increased with increased amounts and frequencies of inorganic germanium application, while chemical components of the soil, such as available phosphate and exchangeable calcium, potassium, and magnesium, decreased with the increased inorganic germanium application. In the 4-year-old P. ginseng, the germanium content was highest in the rhizome and increased in the order of stem, leaf, lateral root, and main root, suggesting that inorganic germanium was absorbed from the root and translocated to the stem and leaf via the rhizome. As for changes in ginsenosides in 4-year-old P. ginseng rhizomes, the contents of ginsenosides Rb1, Rb2, Re, and Rf decreased as the germanium content in soil increased. Ginsenosides Rb₁, Rb₂, Rc, Re, and Rf in the main root also decreased with increasing germanium content in the main root. The results suggest that inorganic germanium treatment may increase organic germanium in harvested P. ginseng, thus enhancing the medicinal effi cacy of ginseng products.

This paper presents an effective and systematic trajectory generation method, together with a control method for enabling a biped robot to walk upstairs. The COG (center of gravity) trajectory is generated by the VHIPM (virtual height inverted pendulum mode) for the horizontal motion and by a 6th order polynomial for the vertical motion; an ankle compliance control (ACC) is also added into the robot control. The proposed methods are evaluated by simulations as well as being implemented in a robot for the performance verification. The results show that the proposed methods can generate stable motions when walking upstairs, and these can significantly reduce the zero moment point (ZMP) errors compared with other methods, enabling the robot to walk up steeper stairs.

Deformation of a megacryst-bearing granitoid pluton has produced a ∼100 m-thick shear zone (viz., Cheongsan shear zone of South Korea) from protomylonite to muscovite-rich ultramylonite, showing variations in microstructural and mineralogical characteristics along the pluton margin. Petrographic observations within the shear zone suggest evidence for various syntectonic K-feldspar and plagioclase (feldspars hereafter) breakdown and muscovite formation through chemical reactions during mylonitization. Megacrysts up to 15 cm long make it difficult to have representative samples for chemical analysis. Here, we have used a mass-balance analysis (i.e., ‘best-fit’ Al–Ti–Fe isocon) for inferring the changes in major element chemistry during the mylonitization of megacryst-bearing granite. The results show variations in alkalies and silica, reflecting concentration changes (loss or gain) by fluid-assisted mass transfer and the role of SiO 2 -rich fluids during progressive development from protolith to ultramylonite of the Cheongsan shear zone. Various bulk-rock volume-changes from 8% loss to 13% gain are calculated relative to the ‘best-fit’ Al–Ti–Fe isocon. Although comparison of the calculated protolith and observed mylonite compositions using ‘best-fit’ isocon analysis may result in uncertainties in interpretation, the present results are consistent with petrographic observations, indicating the element mobility, fluid-assisted mass transfer and the role of SiO 2 -rich fluids during progressive development of the Cheongsan shear zone.

This case study focuses on how a Korean software firm, CCMedia, executed a successful global strategy by merging with its technology partner to gain access to international markets. The case study also reviews the key challenges CCMedia faced after the merger. Intangible assets, such as IT technology, could allow CCMedia to earn overseas capital investment through the merger. With capital and human resources backup from IT Inspire Inc., its former technology partner, CCMedia could enter foreign markets. This case examines the transformation of a strategic technology alliance to a hierarchical structure as a result of a merger. It shows that technology-related alliances could play an important role in possible takeover activities. It provides insights into strategies that technology-based small businesses in Korea could follow to enter international markets.

Objectives We investigated the relationships of serum sex hormone-binding globulin (SHBG) level with known prognostic factors for prostate cancer in men who received radical retropubic prostatectomy (RRP) for clinically localized prostate cancer. Methods Preoperative serum levels of SHBG were analyzed in 288 consecutive patients who were scheduled to undergo RRP for clinically localized prostate cancer. We investigated the potential associations of preoperative serum SHBG level with various clinical and pathological factors. Accuracy of variables in predicting adverse pathological features was assessed via receiver operator characteristics (ROC) curves. Results In univariate analysis, preoperative serum SHBG level was observed to be significantly associated with extraprostatic extension of a tumor ( p =0.019) and with pathological Gleason score ( p =0.001). In multivariate analysis, serum SHBG level ( p =0.039) along with serum PSA ( p p p =0.004) was observed to be an independent predictor of the extraprostatic extension of prostate cancer. The area under ROC curve that demonstrated the performance of a multivariate logistic regression model (MLRM), which included serum SHBG level and other preoperative variables, in predicting extraprostatic extension of tumor was larger than that of MLRM without SHBG (0.797 vs. 0.758, p =0.121). Meanwhile, serum SHBG level was not observed to be significantly associated with pathological Gleason score in multivariate analysis ( p =0.303). Conclusions Our data showed that serum SHBG level is an independent predictive factor for extraprostatic extension of tumor in patients with clinically localized prostate cancer.

The microscale pyrolysis of a mixture of 2,4,6-tribromophenol (2,4,6-TBP) and 2,4,6-trichlorophenol (2,4,6-TCP) was investigated. Several pyrolyzed products resulting from the gas phase reactions were analyzed by gas chromatography/mass spectrometry (GC/MS). Some products, including tetrabromo- and tetrachloro-dibenzo- p -dioxins, were identified by comparison of their retention times and mass spectra with those of products obtained from the pyrolysis of the corresponding 2,4,6-TBP and 2,4,6-TCP. 1,3,6,8- and 1,3,7,9-halogen substituted dioxin isomers were produced as major products via the condensation of phenoxyphenol radicals. The condensation of 2,4,6-TBP led to the more rapid production of tetrabromodibenzo- p -dioxins (TBDDs) than of tetrachlorodibenzo- p -dioxins (TCDDs) from 2,3,6-TCP due to the weaker C–Br than C–Cl bond strength. In the study of a mixture of 2,4,6-TCP and 2,4,6-TBP, the most abundant congeners were dibromo-dichlorodibenzo- p -dioxins. On the basis of the pyro-products analysis, the thermal decay of 2,4,6-TCP and 2,4,6-TBP, and the formation of halogenated dioxins as a function of the pyrolysis temperature were also investigated. The increased reactivity can be explained by the hypothesis that “dibromophenoxy radical are formed more easily by debromination of 2,4,6-TBP than that of 2,4,6-TCP, which rapidly reacts with 2,4,6-TCP and 2,4,6-TBP at low temperatures”. The formation distribution of tetra-bromochlorodibenzo- p -dioxins (tetra-BCDDs) indicated that more chlorinated dioxins were produced at low temperatures, but more brominated dioxins were formed at high temperatures.

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is an optimized technique for the quantitative mapping of trace elements on geological materials. Agate is an aggregate of microcrystalline silica showing a variety of colorful bands due to the species and concentrations of transition metals and is thus an appropriate sample to test the availability, efficiency, and detection limit of LA-ICP-MS trace element mapping. Two fortification agate samples selected for elemental mapping are characterized by the colorful and bluish banding layers, respectively. The colorful agate sample consists mainly of two growth zones varying in color from pale orange-red brown to gray tones, whereas the blue agate sample simply shows alternating blue and white bands. Two different types of mineral inclusions, Fe oxide/hydroxide and hollandite (Ba(Mn4+ 6Mn3+ 2)O16), were identified in the inner and outer halves of the former sample, respectively. The distribution patterns of eight trace elements in these samples, including Al, Co, Cr, Cu, Fe, Mn, Ni, and Ti, were investigated, using both electron microprobe and LA-ICP-MS. Aluminum and Fe are the most abundant trace elements in both agate samples up to 5000 ppm although their concentrations in the colorful agate sample are an order of magnitude higher than those in the blue agate sample. The concentrations of other elements in the agate samples are several parts per million levels. The quantitative maps of the colorful agate sample have shown that Fe was mainly distributed in the inner half, but Al, Cu, and Mn in the outer half. In particular, Fe and Mn were primarily concentrated as small spots. On the other hand, the oscillatory zoning patterns are apparent in the quantitative maps of the blue agate sample, showing a correlative relationship between Al and Ti but an antithetic relationship between Al and Fe. The Al and Fe distribution patterns of the colorful agate sample are reproduced in the Al Kα and Fe Kα X-ray maps, but not clear in blue agate. Quantitative elemental maps using LA-ICP-MS are privileged to visualize trace elements distributions.

In this study, we propose a method to extract landmarks for pose-graph SLAM using only the forward-looking monocular camera mounted in a small mobile robot. By using the sliding window approach, the region of interest is determined to triangulate the landmarks. The landmark extraction process uses multiple sets of bearing information for triangulation. As the landmark is extracted, choose the landmark which is near the navigation plane to project into the 2D landmark node. To test its accuracy, the laser rangefinder is used as a ground truth. Also the various sliding window sizes are tried for a landmark to investigate the effect of the window size on the accuracy. Using this approach as landmark extraction for the SLAM algorithm, we expect to implement monocular based metric SLAM with the graph based back-end optimization.

In this paper, the improved upward-looking camera based SLAM is proposed. With the corner features that are highly robust to the illumination change and contain their orientation information, SLAM performance can improve effectively. The illumination properties from the image can be rejected using the retinex algorithm to make the input image less sensitive to the illumination change. In addition, to deal with the correspondence problem between indistinguishable adjacent corner features, the orientation of the corner feature is additionally taken into account. These robust features are used as a landmark for the extended Kalman filter EKF-based SLAM to evaluate the robustness. A series of experiments show the improved results using the proposed scheme.

Background The restriction of wrist motion results in limited hand function, and the evaluation of the range of wrist motion is related to the evaluation of wrist function. To analyze and compare the wrist motion during four selected tasks, we developed a new desktop motion analysis system using the motion controller for a home video game console. Methods Eighteen healthy, right-handed subjects performed 15 trials of selective tasks (dart throwing, hammering, circumduction, and winding thread on a reel) with both wrists. The signals of light-emitting diode markers attached to the hand and forearm were detected by the optic receptor in the motion controller. We compared the results between both wrists and between motions with similar motion paths. Results The parameters (range of motion, offset, coupling, and orientations of the oblique plane) for wrist motion were not significantly different between both wrists, except for radioulnar deviation for hammering and the orientation for thread winding. In each wrist, the ranges for hammering were larger than those for dart throwing. The offsets and the orientations of the oblique plane were not significantly different between circumduction and thread winding. Conclusions The results for the parameters of dart throwing, hammering, and circumduction of our motion analysis system using the motion controller were considerably similar to those of the previous studies with three-dimensional reconstruction with computed tomography, electrogoniometer, and motion capture system. Therefore, our system may be a cost-effective and simple method for wrist motion analysis.

Photon counting spectral detectors (PCSD) with smaller pixels and efficient sensors are desirable in applications like material decomposition and phase contrast x-ray imaging where discrimination of small signals and fine structure may be desired. Charge sharing in PCSD increases with decreasing pixel sizes and increasing sensor thickness such that the energy calibration or utility of spectral information can become a major hurdle. Utility of a combination of high Z sensors and small pixel sizes in PCSD is limited without efficient threshold calibration and charge sharing mitigation. Here we explore the utility of x-ray tube kVp as a reference to achieve efficient and fast calibration of PCSDs. This calibration method itself does not require rearranging the imaging setup and is not impacted by charge sharing. Our preliminary results indicate that this method can be useful even in scenarios where metal fluorescence and radioactive source based calibration techniques may be practically impossible. Our results are validated using x-ray fluorescence based calibration for a Silicon detector with moderate charge sharing. Calibration of a particularly challenging case of a Medipix2 detector (55 μm pixel size) with a 1 mm thick CdTe sensor and a Medipix3 detector with CdTe sensor is also demonstrated. A cross validation with K-edge identification of Gd is also presented here.