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This study investigates the mechanism of digital linguistic landscapes in enabling engineering education for smart construction according to the educational dimensions of A (ability), S (skill), and K (knowledge). A questionnaire survey was conducted based on the core concepts of the informative dimension and symbolic dimension in digital language landscape as well as the ability dimension, knowledge dimension, and skill dimension in engineering education. Structural equation modeling (SEM) was used as the test method. The results of the research demonstrate that the informative dimension and symbolic dimension are two main aspects of DLL in education of engineering students for smart construction. Additionally, DLL has a significant positive impact on the ability, knowledge, and skill education of engineering students for smart construction. The research has theoretical and practical significance, as it not only enriches research on the relationship between DLL and engineering education for smart construction but also expands the theoretical understanding of engineering education from the perspective of linguistics. Furthermore, the study explores the path of the practical application of digital language landscape to engineering education for smart construction.

This study reports a case study that investigates the gap between BIM tertiary education and the building industry’s needs in New Zealand (NZ). In specific, it aims to (1) identify the industry’s requirements on BIM competencies, (2) examine the status quo of BIM tertiary education in NZ, and (3) identify and analyse the gaps between current BIM education and the industry’s needs. Data were collected through BIM job advertisement to identify the industry’s requirements of BIM competencies and top BIM uses. Data of thirty-three courses were also collected from nine tertiary institutions. Results indicated that there were discrepancies between the type and level (i.e. cognitive levels) of BIM competencies. It was indicated that missing links existed in almost all BIM uses that were taught, except 4D modelling. A large proportion of learning outcomes were focused on ‘understanding’ for several BIM uses, while NZ BIM Handbook requires higher levels of application and evaluation. To bridge the gaps, core competence sets should be determined by disciplines. BIM competencies can also be classified based on BIM uses, BIM processes and phases, and project roles. This paper proposed a conceptual framework, which suggests the way ahead towards future competency-based BIM education. acceptedVersion

海分枝杆菌是一种少见的非典型分枝杆菌，易从皮肤破损处侵入人体而导致感染，主要引起皮肤软组织和手部慢性感染。本文报告1例因“鱼翅刺伤后致右手反复感染不愈2年余”的患者，入院后明确诊断为海分枝杆菌感染并启动规范抗感染治疗，患者右手感染得到有效控制。报道该病例，旨在提高公众对海分枝杆菌感染的认识及引起足够重视。.

1. To explore the genetic diversity of Chinese indigenous chicken breeds, a 585 bp fragment of the mitochondrial DNA (mtDNA) region was sequenced in 102 birds from the Xichuan black-bone chicken, Yunyang black-bone chicken and Lushi chicken. In addition, 30 mtDNA D-loop sequences of Silkie fowls were downloaded from NCBI. The mtDNA D-loop sequence polymorphism and maternal origin of 4 chicken breeds were analysed in this study. 2. The results showed that a total of 33 mutation sites and 28 haplotypes were detected in the 4 chicken breeds. The haplotype diversity and nucleotide diversity of these 4 native breeds were 0.916 ± 0.014 and 0.012 ± 0.002, respectively. Three clusters were formed in 4 Chinese native chickens and 12 reference breeds. Both the Xichuan black-bone chicken and Yunyang black-bone chicken were grouped into one cluster. Four haplogroups (A, B, C and E) emerged in the median-joining network in these breeds. 3. It was concluded that these 4 Chinese chicken breeds had high genetic diversity. The phylogenetic tree and median network profiles showed that Chinese native chickens and its neighbouring countries had at least two maternal origins, one from Yunnan, China and another from Southeast Asia or its surrounding area.

Recently, Lane departure warning system has attracted great attention as it contributes to vehicle active safety. In this paper, a vision-based lane departure warning system under high-speed driving is proposed. The system consists of two functional parts: lane markings detection and vehicle departure identification. The Hough Transform is applied to detect lane boundaries, which is a most effective detection method with high reliability. Based on the road line, a method using several Euclidean-distance-related parameters to calculate vehicle’s position and its deviating status is proposed, which addresses the problem of efficient detection of lane departure under high-speed driving condition. The algorithm is tested and verified in various real driving conditions and proved a reliable and steady performance.

The present Tarim Basin of China presents drilling chanllenges moving toward deeper hydrocarbon reservoirs, which includes more complex formation, poor bit cutting efficiency and wellbore integrity. The paper introduces the development and application of optimizer of drilling operating parameters named as Smart Driller Indicator (SDI) which worked to deliver continuous improvement in axial vibration and stick-slip mitigation for the presented field. SDI is based on a soft-closed-loop solution called NAVO real-time vibration monitoring and calculating the optimal drilling parameters for that formation by maintaining an optimum relationship between ROP and energy input. From the perspectives of rock mechanics and conservation of energy, the ideal performance in the optimum proportion among drilling parameters, ROP and MSE have been derived from comprehensive analysis of optimized drilling mechanism. An advanced damped forced torsional vibrarion model in frenquency-domain was developed. Field validation for real-time estimates produced by the model was conducted by a drilling mechanics module sub. In drlling process, if the ROP is not as good as expected, SDI will automatically evaluates the new hole conditions including the mechanical properties of the formation, bit wear condition and vibration etc, and updates the optimum drilling parameters. The drillers just adjust drilling parameters to follow them, a higher ROP (rate of penetration) and a longer bit run can be achieved. SDI has been applied for more than 20 wells with total footage of over 30,000ft and has shown about 20%-54% ROP improvement and longer bit life compared with conventional driller's drilling habits and totally 125 days and about 1 million dollars have been saved. As an effective tool for further excavating the potential of ROP, SDI might achieve satisfactory outcomes that overcome the drilling challenges of carbonate formation, gravel and igneous in deep wells.

The sidereal cosmic-ray anisotropy at TeV energies has a large-scale deficit region distributed between 150 and 240 degrees in right ascension, which is called the “loss-cone”. The Milagro experiment reported the detection of a steady increase in the loss-cone amplitude at 6 TeV from July 2000 to July 2007. In this paper, we examine Milagro’s claim using the data collected by the Tibet air-shower experiment from November 1999 through December 2008. No time dependence was found in the loss-cone amplitude at 4.4, 6.2, and 11 TeV. If the increase in the loss-cone amplitude were, as Milagro argued, due to variations in the heliosphere in relation to solar activities, the same tendency would be seen at sub-TeV energies where the anisotropy is far more sensitive to solar activities. At 0.6 TeV, however, Matsushiro underground muon observatory reported no significant increase in the loss-cone amplitude during the corresponding period.

Using the Tibet-III air shower array, we search for steady TeV -rays from 18 pulsars in the Fermi Large Area Telescope pulsar catalog. Among them, we ob- serve 8 sources including the Crab instead of the expected

The observation of the extensive air showers has been carried out since 1990 by Tibet air-shower array to study the origin of the cosmic-rays. In order to investigate the chemical composition around the knee, air-shower core detector was used in two experimental phases aiming to separate light primary elements (proton and helium). In a first phase experiment made in 1996-1999, primary proton and helium spectra were measured using a hybrid detector consisted of Tibet II air-shower array, emulsion chambers, and burst detectors. The result indicated that the fraction of light elements among the all particle spectrum is less than 30%. We performed the second phase experiment in 2002-2005 to measure proton + helium together to confirm the previous result with higher statistics by improving the detection efficiency for the air-shower cores. The P + He spectrum was obtained in a good agreement with previous result by several times higher statistics. The flux of the light elements, together with the all-particle energy spectrum, indicates the dominance of nuclei heavier than helium in the energy range around the knee. We also present the outline of the next phase experiment, which is to measure the heavy elements around the knee, using low threshold air-shower core detector named YAC. (C) 2010 COSPAR. Published by Elsevier Ltd. All rights reserved.

To improve reproducibility, stability and sensitivity, a bismuth (Bi) thin film was coated on glassy carbon (GC) substrates which surfaces were modified with a porous thin layer of polyaniline (PANI) via multipulse potentiostatic electropolymerization to form Bi/PANI/GC electrodes (Bi/PANI/GCEs). The Bi/PANI/GCEs were used successfully for simultaneous detection and determination of Cd2+ and Pb2+ ions, and various parameters were studied with reference to square wave anodic stripping voltammetric (SWASV) signals. The experimental results depicted that the environment-friendly Bi/PANI/GCEs had the ability to rapidly monitor trace heavy metals even in the presence of surface-active compounds.

The Tibet-III air shower array, consisting of 789 scintillation detectors, has been operating successfully at Yangbajing in Tibet since 1999. Some recent results on gamma-ray observation by the Tibet-III air shower array are introduced and its future prospects of gamma-ray observation will be discussed.

Recent results and future prospects of the Tibet air-shower experiment are reported on the all-particle energy spectrum and the chemical composition of cosmic rays around 10 15 eV energy range. The knee of the all-particle energy spectrum has been clearly observed at the energy around 4 ×10 15 eV by Tibet III air-shower array located at Yangbajing, Tibet, China (atmospheric depth 606 g/cm 2 , area 37,000 m 2 ). The energy spectrum of light components (protons and helium) measured by air-shower-core detector exhibits steeper power index than that of direct measurements below 10 14 eV, leading to decreasing fraction of the light component toward the knee. Hence, it is strongly suggested that the origin of the knee is related with the change of the chemical composition of cosmic rays. A new air-shower-core detector called `YAC' is under the preparation for explicit measurement of the heavy component.

The Tibet-III air shower array, consisting of 533 scintillation detectors, has been operating successfully at Yangbajing in Tibet, China since 1999. Using the dataset collected by this array from 1999 November through 2005 November, we obtained the energy spectrum of $\gamma$-rays from the Crab Nebula, expressed by a power law as $(dJ/dE) = (2.09\pm0.32)\times10^{-12} (E/{\rm 3 TeV})^{-2.96\pm0.14} {\rm cm}^{-2} {\rm s}^{-1} {\rm TeV}^{-1}$ in the energy range of 1.7 to 40 TeV. This result is consistent with other independent $\gamma$-ray observations by imaging air Cherenkov telescopes. In this paper, we carefully checked and tuned the performance of the Tibet-III array using data on the moon's shadow in comparison with a detailed Monte Carlo simulation. The shadow is shifted to the west of the moon's apparent position as an effect of the geomagnetic field, although the extent of this displacement depends on the primary energy positively charged cosmic rays. This finding enables us to estimate the systematic error in determining the primary energy from its shower size. This error is estimated to be less than $\pm$12% in our experiment. This energy scale estimation is the first attempt among cosmic-ray experiments at ground level. The systematic pointing error is also estimated to be smaller than $0\fdg011$. The deficit rate and position of the moon's shadow are shown to be very stable within a statistical error of $\pm$6% year by year. This guarantees the long-term stability of point-like source observation with the Tibet-III array. These systematic errors are adequately taken into account in our study of the Crab Nebula., Comment: 12 pages, 16 figures, accepted by ApJ

Nitrogen-doped tetrahedral amorphous carbon (ta-C : N) films were deposited by filtered cathodic vacuum arc (FCVA) technique using nitrogen as a background gas. The structure of the ta-C : N films was studied with X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy in terms of nitrogen flow rate used during the film deposition. Potential windows of the films measured in deaerated and unstirred solutions, such as 0.5 M HCl, 0.1 M KCl, 0.1 M NaCl, 0.1 M KOH, and 0.1 M NaOH, were about 2.4, 2.32, 3.2, 3.1, and 3.25 V, respectively. This study showed that the potential windows of the ta-C : N films were also affected by nitrogen flow rate. The ta-C : N films used in this study had the desired voltammetric characteristics suitable for electrochemical analysis.

We present an updated all-particle energy spectrum using data collected in the period from 2000 November through 2004 October by Tibet III air-shower array. The energy determination of the air showers is made by fitting the lateral density distribution of the shower particles to the modified NKG function which is optimized by simulation calculation using interaction models of QGSJET01c and SIBYLL2.1 taking into account of the detector configurations. It is shown that the model dependence in the energy determination is not significant, being less than 5% in the absolute flux value, and we obtained the cosmic ray energy spectrum in a wide range over 3 decades between 10(14) eV and 10(17) eV, in which the position of the knee is clearly seen at around 4 PeV. The spectral index is -2.68 +/- 0.02(stat.) below 1PeV, while it is -3.12 +/- 0.01(stat.) above 4 PeV. The various systematic errors are under study now.

We are planning to build a large water-Cherenkov-type muon detector array around the Tibet air shower array for Gamma-ray astronomy in the 100 TeV Region. In this paper, we describe the design of the Tibet MD array and details of the Monte Carlo simulation to demonstrate the sensitivity of the Tibet AS+MD array.

The Tibet air shower array with effective area 37,000 m 2 located at 4300m in altitude, in Tibet, China, is sensitive to celestial gamma rays with energies above a few TeV. We have a plan to add a large underground muon detector array to it in order to discriminate cosmic gamma rays from cosmic-ray hadrons and to increase its sensitivity by approximately one order of magnitude to cosmic gamma rays in the 100 TeV energy region. The overview of the plan will be briefly described.

We searched for steady 100 TeV gamma-ray point sources from −10° to +70° in declination based on six year data obtained from Nov. 1999 to Nov. 2005 by the Tibet air shower array. No new source was found and no significant excess of events could be detected from known TeV sources. We set flux upper limits above 100 TeV on several nearby objects located inside Our Galaxy. All of them are slightly higher than extrapolation from lower energies by a factor of 1 to 20. Our new project named Tibet MD will improve our sensitivity by a factor of ∼10 in this energy region. We would discover ∼10 new sources and be able to measure cutoff energy of known and unknown sources, which might lead to identification of the origin of cosmic rays.

We report on the spectral index of cosmic rays around 10 TeV energy region obtained by observation of the Compton-Getting anisotropy due to the terrestrial orbital motion around the Sun with the Tibet III air shower array during the period from 1999 to 2005. The spectral index has turned out to be 2.99 ± 0.54 , which is consistent with 2.74 by the direct energy spectrum measurement. This method is a new approach to measure the spectral index and is complementary to the conventional energy spectrum measurement.

The epitaxially stabilized metallic α-FeSi2 thin films on Si(001) were grown using pulsed laser deposition. While the bulk material of α-FeSi2 is a high temperature metastable phase and nonmagnetic, the thin film is stabilized at room temperature and shows unusual electronic transport and magnetic properties due to strain modification. The transport renders two different conducting states with a strong crossover at 50 K accompanied by an onset of ferromagnetism as well as a substantial magnetocaloric effect and magnetoresistance. These experimental results are discussed in terms of the unusual electronic structure of α-FeSi2 obtained within density functional calculations and Boltzmann transport calculations with and without strain. Our findings provide an example of a tailored material with interesting physics properties for practical applications.

The Tibet hybrid experiment composed of emulsion chambers, burst detectors and the Tibet-II air-shower array was done at Yangbajing (4,300m above sea level, 606 g/cm2) in Tibet. For 3-year operation, we have observed 177 γ-families (ΣEγ > 20 TeV) accompanying air showers with the shower size Ne > 2 × 105. Using this data set and a neural network method to select proton and helium induced events, the primary proton and helium energy spectra are deduced between 1015 and 1016eV. The proton spectrum, thus obtained, can be expressed by a single power-law function with a differential index of −3.01±0.11 and −3.05±0.12 based on the QGSJET+HD and SIBYLL+HD models, respectively, which are steeper than that extrapolated from the direct observations of −2.74±0.01 in the energy range below 1014 eV. Our result suggests that the main component responsible for making the knee structure of the all-particle spectrum should be composed of nuclei heavier than helium.

Simultaneous observation of gamma-families and their accompanying air showers was performed at Yangbajing (4300 m above sea level) in Tibet with the emulsion chambers and burst detectors which were linked with the Tibet-II air-shower array. For three years operation, we observed 177 gamma-families (Sigma E-gamma > 20 TeV) accompanying air showers with the size N-e > 2 x 10(5). Using this data and the simulation code CORSIKA, we obtained the primary proton spectrum in the energy range of 10(15)-10(16) eV. The slope of the observed spectrum is steeper than that extrapolated smoothly from the lower energy region below 10(14) eV, irrespective of the interaction models assumed in the simulation. The uncertainty of the absolute flux of protons due to the interaction model dependence involved in the simulation codes is at most 30%, which is much weaker than results of other air-shower experiments. Our experiment shows low intensity of light components (proton and helium) independent of the interaction models suggesting that the main component responsible for making the knee structure of the all-particle spectrum is composed of nuclei heavier than helium. This is the first measurement of the differential energy spectra of primary protons by selecting them event by event at the knee energy region.

According to many solar observations, the solar activity, during the Solar Cycle 23, is gradually declining to the quiet phase from the high state in 2000–2004. The Tibet air shower array has been continuing the observation of the shadow that cosmic rays make in the direction of the sun or the moon since 1991. We have shown the influence of the magnetic field around the sun, the interplanetary and the geomagnetic fields for the sun shadow at the multi-TeV region. We discuss the variation of the Sun’s shadow with the Gnevyshev gap (GG) in the maximum phase of the Solar Cycle 23. Unfortunately, the bottom in GG corresponds to off-observation period. Nonetheless, we found the anti-correlation between the significance of the Sun’s shadow and the variation of the magnetic field intensity around GG, although the statistical significance is not so high. It is expected that a detailed analysis of the Sun’s shadow will reveal interesting features of the anti-correlation.

A hybrid experiment consisting of emulsion chambers, burst detectors and the Tibet II air-shower array was carried out at Yangbajing (4,300 m a.s.l., 606 g/cm$^2$) in Tibet to obtain the energy spectra of primary protons and heliums. From three-year operation, these energy spectra are deduced between $10^{15}$ and $10^{16}$ eV by triggering the air showers associated with a high energy core and using a neural network method in the primary mass separation. The proton spectrum can be expressed by a single power-law function with a differential index of $-3.01 \pm 0.11$ and $-3.05 \pm 0.12$ based on the QGSJET+HD and SIBYLL+HD models, respectively, which are steeper than that extrapolated from the direct observations of $-2.74 \pm 0.01$ in the energy range below $10^{14}$ eV. The absolute fluxes of protons and heliums are derived within 30% systematic errors depending on the hadronic interaction models used in Monte Carlo simulation. The result of our experiment suggests that the main component responsible for the change of the power index of the all-particle spectrum around $3 \times 10^{15}$ eV, so-called ``knee'', is composed of nuclei heavier than helium. This is the first measurement of the differential energy spectra of primary protons and heliums by selecting them event by event at the knee energy region., Comment: This paper has been accepted for publication Physics Letters B on October 19th, 2005. This paper has been accepted for publication Physics Letters B on October 19th, 2005

The Tibet experiment, operating at Yangbajing (4,300 m above sea level), is the lowest energy air shower array and the new high density array constructed in 1996 has sensitivity to $\gamma$-ray air showers at energies as low as 3 TeV. With this new array, the Crab Nebula was observed in multi-TeV $\gamma$-rays and a signal was detected at the 5.5 $\sigma$ level. We also obtained the energy spectrum of $\gamma$-rays in the energy region above 3 TeV which partially overlaps those observed with imaging atmospheric Cherenkov telescopes. This is the first observation of $\gamma$-ray signals from point sources with a conventional air shower array using scintillation detectors.

We examined the Sun's shadow by 10 TeV cosmic rays observed with the Tibet air shower array during the period from 1991 through 1997. The results suggest that there is a causal relation between the shadow's movement and the changing inclination of the heliospheric current sheet of the large-scale solar magnetic field. Thus, further observations with higher statistics may provide direct information on the relation between a time variation of the large-scale structure of the solar and interplanetary magnetic fields and the phase of solar activity cycle.

The ARGO-YBJ experiment is currently under construction at the Yangbajing Cosmic Ray Laboratory (4300 m a.s.l.).The detector consists of a central carpet, 74 × 78 m2, made of a single layer of Resistive Plate Counters (RPCs), and surrounded by a partially instrumented guard ring for a total instrumented area of about 6700 m2. The digital read-out, performed by means of pick-up electrodes 6.7 × 62 cm2 (strip), allows to measure the charged particle number of small size air showers. The technique of counting the number of fired strips on the ARGO carpet corresponds to operate in the 10÷500 TeV energy region where both direct and indirect measurements on the primary cosmic radiation have been performed. Many composition models have been proposed by different experiments. In this work we discuss the ability of the ARGO detector to discriminate among some models.

In this work we investigate c-Si solar cells in which a two steps (double) screen-printing is implemented for the front contact in order to increase the aspect ratio of the fingers. To this purpose numerical simulations are performed on a solar cell and metallization properties are defined according to experimental data. The analysis of solar cells with conventional single screen-printing is also performed for comparison. In agreement with experiments we show the efficiency improvement of double printing over single printing. The analysis of electrical parameters (fill factor, short-circuit current and open-circuit voltage) allows to understand the source of the enhanced efficiency.

High efficiency silicon monocrystalline solar cells commonly adopt point contacted rear surfaces to reduce the recombination losses in the rear side of the device. However, the reduction of the rear contact surface leads to an increase of series resistance losses. Modeling and analysis of rear point contact solar cells is strategic to optimize the device design by taking into account several competing physical mechanisms. Owing to their complicated geometries, the analysis of these devices requires three-dimensional (3-D) numerical simulation. In this work we analyze the influence of the most important geometrical and electrical parameters on the conversion efficiency of rear point contact solar cells.

Two-dimensional (2-D) numerical simulations have been performed to investigate the impact of the doping profile in the metal-contacted highly-doped regions for c-Si selective emitter (SE) solar cells. Numerical results show that the doping profile under the metallization significantly influences the recombination effects on the front-side of the SE cell and consequently its performance. A strong impact on the short-circuit current density of the solar cell has been seen. This is mainly due to the inclusion of large alignment tolerances used in the SE diffusion for the subsequent metallization process, leading to broad highly-doped areas. In this regard, a quantitative analysis of this effect has been carried out. The results reveal that an improved alignment, allowing a reduction of the alignment tolerances, leads to a wider process window of doping profiles and hence better SE cell performance.

We search for steady TeV γ-rays from 18 pulsars in the Fermi-LAT pulsar catalog using the Tibet air shower array. We observe 8 sources including the Crab against expected 0.41 sources at a significance of 2σ or more among the 18 pulsars. The chance probability from Poisson statistics is estimated to be 1.4×10-8.With the Crab excluded, it is estimated to be 1.8×10-7. These low chance probabilities clearly show that the Fermi pulsars have a statistically significant correlation with TeV γ-ray excesses observed by the Tibet air shower array.

Screen printable etch paste was developed for low cost patterning of dielectric films. This technique offers a simple print and bake approach to pattern without the need for a rinse step. Residue analysis of the etched area showed no sign of any organic residue left behind by the etch process. High carrier lifetime indicates no significant contamination or silicon surface damage. The etched via diameter of 150 µm was demonstrated in thermal oxide while smaller via size of 100 µm was achieved in silicon nitride (SiN x ) or a combination of silicon oxide and nitride. Contact resistance measurement through the etched vias using TLM method showed values less than 3mΩ.cm2. The etch paste and process technique can be easily used in PERC cell as well as advanced architecture Interdigitated Back Contact (IBC) cell for low cost patterning.

We analyze the large-scale two-dimensional sidereal anisotropy of multi-TeV cosmic rays by Tibet Air Shower Array, with the data taken from 1999 November to 2008 December. To explore temporal variations of the anisotropy, the data set is divided into nine intervals, each in a time span of about one year. The sidereal anisotropy of magnitude about 0.1% appears fairly stable from year to year over the entire observation period of nine years. This indicates that the anisotropy of TeV Galactic cosmic rays remains insensitive to solar activities since the observation period covers more than a half of the 23rd solar cycle., 18 pages, 2 figures, accepted by The Astrophysical Journal

Mapping the global heliosphere by detecting energetic neutral atoms (ENAs), IBEX derived the semi‐direct information on the structure of the large‐scale magnetic field surrounding the heliosphere. Multi‐TeV galactic cosmic rays (GCRs) also sense the global structure of the magnetic field within the whole heliosphere as well as the field surrounding the heliosphere, and can provide an additional tool to explore the global structure of these fields. We analyze, in this context, the multi‐TeV GCR intensity observed with the Tibet Air Shower (AS) experiment, which clearly shows a midscale component structure observed as the excess intensity along Gurnett’s HDP (Hydrogen Deflection Plane), as well as the global component structure. We find that the amplitude of the midscale component is only weakly dependent on GCR energy, while its angular extension along the HDP plane monotonously decreases with increasing energy. On the basis of these results, we discuss the possible origin of the midscale anisotropy.

Using the data taken from Tibet II High Density (HD) Array (1997 February-1999 September) and Tibet-III array (1999 November-2005 November), our previous northern sky survey for TeV $\gamma-$ray point sources has now been updated by a factor of 2.8 improved statistics. From $0.0^{\circ}$ to $60.0^{\circ}$ in declination (Dec) range, no new TeV $\gamma-$ray point sources with sufficiently high significance were identified while the well-known Crab Nebula and Mrk421 remain to be the brightest TeV $\gamma-$ray sources within the field of view of the Tibet air shower array. Based on the currently available data and at the 90% confidence level (C.L.), the flux upper limits for different power law index assumption are re-derived, which are approximately improved by 1.7 times as compared with our previous reported limits., Comment: This paper has been accepted by hepnp

We are planning to build a 10,000 m2 water‐Cherenkov‐type muon detector (MD) array under the Tibet air shower (AS) array. The Tibet AS+MD array will have the sensitivity to detect gamma rays in the 100 TeV region by an order of the magnitude better than any other previous existing detectors in the world. In the late fall of 2007, a prototype water Cherenkov muon detector of approximately 100 m2 was constructed under the existing Tibet AS array. The preliminary data analysis is in good agreement with our MC simulation. We are now ready for further expanding the underground water Cherenkov muon detector.

We have already reported the first result on the all-particle spectrum around the knee region based on data from 2000 November to 2001 October observed by the Tibet-III air-shower array. In this paper, we present an updated result using data set collected in the period from 2000 November through 2004 October in a wide range over 3 decades between $10^{14}$ eV and $10^{17}$ eV, in which the position of the knee is clearly seen at around 4 PeV. The spectral index is -2.68 $\pm$ 0.02(stat.) below 1PeV, while it is -3.12 $\pm$ 0.01(stat.) above 4 PeV in the case of QGSJET+HD model, and various systematic errors are under study now., Comment: 12 pages, 7 figures, accepted by Advances in space research

The amplitude of the Compton-Getting (CG) anisotropy contains the power-law index of the cosmic-ray energy spectrum. Based on this relation and using the Tibet air-shower array data, we measure the cosmic-ray spectral index to be $-3.03 \pm 0.55_{stat} \pm < 0.62_{syst}$ between 6 TeV and 40 TeV, consistent with $-$2.7 from direct energy spectrum measurements. Potentially, this CG anisotropy analysis can be utilized to confirm the astrophysical origin of the ``knee'' against models for non-standard hadronic interactions in the atmosphere., accepted to ApJL