Recent studies by the Hong Kong Observatory show that the urban centre of Hong Kong has considerable Urban Heat Island （UHI） effect that arises from the different thermal properties between urban and the surrounding...Recent studies by the Hong Kong Observatory show that the urban centre of Hong Kong has considerable Urban Heat Island （UHI） effect that arises from the different thermal properties between urban and the surrounding rural areas. The studies have also shown that the urban-rural temperature difference or UHI intensity in the urban centre of Hong Kong can be greater than 10℃. However, the characteristics of UHI in Hong Kong would not be unique were it not for its complex topography and the significant spatial variation in the degree of urbanization within the territory. Making use of the extensive spatial coverage of the automatic weather stations operated by the Observatory, this study attempts to document the spatial variation of the characteristics of UHI effect in Hong Kong in summer and winter through cases studies. Cases in summer and winter with meteorological conditions typical for high UHI effect （that is, clear sky, light wind and stable atmospheric condition） are selected for the study. The characteristics of UHI effect in terms of the daytime warming rates, nocturnal cooling rates and diurnal temperature ranges at the selected automatic weather stations are analysed. The territory of Hong Kong is then classified into different categories according to the identified characteristics with a view to portraying the spatial morphology of UHI effect in Hong Kong.展开更多
Deformation behavior of the Mg-8 wt%Li alloy at high strain rate was studied by means of the Split Hopkinson Pressure Bar （with strain rate of 10^3 s^-1）. It is found that shear localization proves to be the main da...Deformation behavior of the Mg-8 wt%Li alloy at high strain rate was studied by means of the Split Hopkinson Pressure Bar （with strain rate of 10^3 s^-1）. It is found that shear localization proves to be the main damage mode for the alloy during dynamic loading. Strain and strain rate arc the two necessary parameters affecting the occurrence of deformation and shear bands. Deformation bands begin to form when the strain and strain rate reach 0.20 and 1 900 s^-1 respectively and will develop gradually with the strain rate increasing. Besides, deformation bands will transform into shear bands when the strain and strain rate reach above 0.25 and 3 500 s^-1 separately.展开更多
Objective： To observe the electrocardiogram （ECG） and heart rate in a rabbit model ofhyperkalemia induced by potassium chloride, and provide theoretical and experimental reference for timely diagnosis of hyperkalem...Objective： To observe the electrocardiogram （ECG） and heart rate in a rabbit model ofhyperkalemia induced by potassium chloride, and provide theoretical and experimental reference for timely diagnosis of hyperkalemia clinically. Methods： Forty rabbits were randomly assigned into four groups. 0.9% isotonic saline solution was perfused in the group I , while 1.0%, 4.0% and 10.0% potassium chloride solutions were perfused in the other groups, respectively, to induce hyperkalemia. Results： The changes of serum potassium, ECG and heart rate before perfusion were significantly （P〈 0.05） different from those after perfusion in the other groups compared with group I . The effect of ECG variability rates was well consistent （Kappa = 0.724, P〈0.01） with that of serum potassium on diagnostic tests in the other groups. The area under ROC curve in diagnosis effect of ECG variability rates and sermn potassium on hyperkalaemia was much significantly larger （P〈0.01 and P〈0.05） compared with 0.5. There was asignificantly positive correlation between ECG variability rates and serum potassium （r= 0.865, P〈0.05 for bilateral Pearson test）. There was certain positive correlation between heart rate and serum potassium, but the correlation was poor （r= 0.526, R2=0.277）. Conclusion： A combination of serum potassium, ECG variability rates and heart rate should be considered and analyzed by synthesis to establish an accurate and timely diagnosis for hyperkalemia.展开更多
In Africa, donkeys have significant contribution in traction operation, but there is little research related to workload and their welfare. The objective of this work was to examine the effect of various loads on donk...In Africa, donkeys have significant contribution in traction operation, but there is little research related to workload and their welfare. The objective of this work was to examine the effect of various loads on donkeys＇ physiological and behavioural responses to evaluate welfare. Donkeys weighing of 132-172 kg （159 ± 11 kg） and totally 20 were used for the experiment. The experimental design included two wheeled cart × seven load class （an increment of 100 kg） with five repetitions each, and the travelled distance was 2 km. Travelled time, behavioural occurrences and physiological responses were recorded. Statistical analysis was conducted using SAS （version 9.4） software programme. When loads were 500-700 kg, heavy and rapid panting and falling down occurred frequently. When loads increased successively and reached 500, 600 and 700 kg, speed started declining from 3.68 km/hto 3.5, 2.94 and 2.54 krn/h, respectively, indicating that speed and applied loads are inversely correlated （P 〈 0.001）. Heart rate was 129 ± 11 bpm at 700 kg, and in respect to resting state, donkeys＇ heart rate elevated by a factor of up to 3. As the load exceeded 400 kg, the speed declined significantly, and behavioural occurrences like heavy panting and falling down confirmed this. This leads to the conclusion that donkeys could pull about 2.7 times of their live weight. But if they have continuous and long working hours （about 6 h）, it is recommended to keep load of two wheeled cart about double of donkeys live weight so as to safe guard donkeys＇ welfare.展开更多
The purpose of this paper is to improve allocation of the number of bits without skipping the frame by accurately estimating the target bits in H. 264/AVC rate control. The scheme ImPoses an enhancement method of the ...The purpose of this paper is to improve allocation of the number of bits without skipping the frame by accurately estimating the target bits in H. 264/AVC rate control. The scheme ImPoses an enhancement method of the target frame rate based on H. 264/AVC bit allocation. The enhancement uses a frame complexion estimation to improve the existing Mean Absolute Difference （MAD） complexity measurement. Bit allocation to each frame is not just computed by target frame rote but also adjusted by a combined frame complexity measure. Using the statistical characteristic, the scheme obtains change of occurrence bit about QP to apply the bit amount by QP from the video characteristic and apply it in the estimated bit amount of the current frame. Simulation results show that the proposed rate eontrol scheme achieves time saving of mine than 99% over existing rate control algorithm. Nevertheless, Peak Signal-to-Noise Ration （PSNR） and bit rate were almost the same as the performances.展开更多
Different teaching philosophies derive from different cultural background.There are many differences between American and Chinese teaching philosophies because of their different cultural background.Under the guidance...Different teaching philosophies derive from different cultural background.There are many differences between American and Chinese teaching philosophies because of their different cultural background.Under the guidance of different philosophies,there are different teaching styles between American and Chinese Classroom teaching.展开更多
First of all it is necessary to point out that 'reciting' is the wrong term for what Chinese students are often asked to do when they are learning English. The correct terms are, 'learning by heart'... First of all it is necessary to point out that 'reciting' is the wrong term for what Chinese students are often asked to do when they are learning English. The correct terms are, 'learning by heart' or 'rote learning'. In this article the term 'rote learning' will be used.……展开更多
This study investigates differential effects of etymological elaboration and rote memorization on idiom acquisition and retention in Chinese college EFL learners. The sample (N = 70) involved two intact groups of coll...This study investigates differential effects of etymological elaboration and rote memorization on idiom acquisition and retention in Chinese college EFL learners. The sample (N = 70) involved two intact groups of college students. Subjects in one group exposed to instruction in the form of etymological familiarity while subjects in the comparison group were asked to memorize idioms on the basis of their given meaning. Subjects were then administered two post-tests: one to assess initial idiom acquisition, and another four weeks later to assess idiom retention. Statistical analyses produced sufficient support for both the first hypothesis (that the etymological elaboration condition would acquire more idioms than the rote memorization condition), and the second hypothesis—that the etymological familiarity would exhibit superior retention rates. The finding of this study suggests that for the purpose of encouraging long-term retention, elaborating on the original usage of idioms is preferable to requiring students to learn idioms by rote.展开更多
A systematic dependence of shape fluctuation energy product SFE ＊ B（E2）↑ and rotational energy product ROTE ＊ B（E2）↑ on the valence nucleon product Np Nn is carried out in the Z = 50-82,N = 82-126 major shell ...A systematic dependence of shape fluctuation energy product SFE ＊ B（E2）↑ and rotational energy product ROTE ＊ B（E2）↑ on the valence nucleon product Np Nn is carried out in the Z = 50-82,N = 82-126 major shell space.For the shape transitional nuclei,the product SFE＊B（E2）↑ drops to zero and becomes negative,indicating direct dependence on N_pN_n.A relative rise,on the other hand,is observed in the product ROTE＊B（E2） ↑plotted against N_pN_n for all the nuclei in Z = 50-82 and N = 82-126.In the N 〉 104 region,large positive values of the product SFE ＊ B（E2） ↑ are observed for the Pt nucleus,which indicates sphericity.A systematic study of the product SFE ＊ B（E2）↑ and ROTE ＊ B（E2） ↑ with atomic number Z is also discussed.The products SFE ＊ B（E2） ↑and ROTE ＊ B（E2） ↑ vary sharply with Z for the N = 88 isotones.We discuss here for the first time the correlation between SFE ＊ B（E2） ↑ and ROTE ＊ B（E2） ↑ with valence nucleon product N_pN_n.展开更多
文摘Recent studies by the Hong Kong Observatory show that the urban centre of Hong Kong has considerable Urban Heat Island （UHI） effect that arises from the different thermal properties between urban and the surrounding rural areas. The studies have also shown that the urban-rural temperature difference or UHI intensity in the urban centre of Hong Kong can be greater than 10℃. However, the characteristics of UHI in Hong Kong would not be unique were it not for its complex topography and the significant spatial variation in the degree of urbanization within the territory. Making use of the extensive spatial coverage of the automatic weather stations operated by the Observatory, this study attempts to document the spatial variation of the characteristics of UHI effect in Hong Kong in summer and winter through cases studies. Cases in summer and winter with meteorological conditions typical for high UHI effect （that is, clear sky, light wind and stable atmospheric condition） are selected for the study. The characteristics of UHI effect in terms of the daytime warming rates, nocturnal cooling rates and diurnal temperature ranges at the selected automatic weather stations are analysed. The territory of Hong Kong is then classified into different categories according to the identified characteristics with a view to portraying the spatial morphology of UHI effect in Hong Kong.
基金Aeronautical Science Foundation of China (04G54009)
文摘Deformation behavior of the Mg-8 wt%Li alloy at high strain rate was studied by means of the Split Hopkinson Pressure Bar （with strain rate of 10^3 s^-1）. It is found that shear localization proves to be the main damage mode for the alloy during dynamic loading. Strain and strain rate arc the two necessary parameters affecting the occurrence of deformation and shear bands. Deformation bands begin to form when the strain and strain rate reach 0.20 and 1 900 s^-1 respectively and will develop gradually with the strain rate increasing. Besides, deformation bands will transform into shear bands when the strain and strain rate reach above 0.25 and 3 500 s^-1 separately.
基金Supported by Natural Science Foundation of Chengdu Medical College(CYZ09-004)The "Challenge Cup" Sichuan Undergraduate Curricular Academic Science and Technology Works(CT11D-1006)
文摘Objective： To observe the electrocardiogram （ECG） and heart rate in a rabbit model ofhyperkalemia induced by potassium chloride, and provide theoretical and experimental reference for timely diagnosis of hyperkalemia clinically. Methods： Forty rabbits were randomly assigned into four groups. 0.9% isotonic saline solution was perfused in the group I , while 1.0%, 4.0% and 10.0% potassium chloride solutions were perfused in the other groups, respectively, to induce hyperkalemia. Results： The changes of serum potassium, ECG and heart rate before perfusion were significantly （P〈 0.05） different from those after perfusion in the other groups compared with group I . The effect of ECG variability rates was well consistent （Kappa = 0.724, P〈0.01） with that of serum potassium on diagnostic tests in the other groups. The area under ROC curve in diagnosis effect of ECG variability rates and sermn potassium on hyperkalaemia was much significantly larger （P〈0.01 and P〈0.05） compared with 0.5. There was asignificantly positive correlation between ECG variability rates and serum potassium （r= 0.865, P〈0.05 for bilateral Pearson test）. There was certain positive correlation between heart rate and serum potassium, but the correlation was poor （r= 0.526, R2=0.277）. Conclusion： A combination of serum potassium, ECG variability rates and heart rate should be considered and analyzed by synthesis to establish an accurate and timely diagnosis for hyperkalemia.
文摘In Africa, donkeys have significant contribution in traction operation, but there is little research related to workload and their welfare. The objective of this work was to examine the effect of various loads on donkeys＇ physiological and behavioural responses to evaluate welfare. Donkeys weighing of 132-172 kg （159 ± 11 kg） and totally 20 were used for the experiment. The experimental design included two wheeled cart × seven load class （an increment of 100 kg） with five repetitions each, and the travelled distance was 2 km. Travelled time, behavioural occurrences and physiological responses were recorded. Statistical analysis was conducted using SAS （version 9.4） software programme. When loads were 500-700 kg, heavy and rapid panting and falling down occurred frequently. When loads increased successively and reached 500, 600 and 700 kg, speed started declining from 3.68 km/hto 3.5, 2.94 and 2.54 krn/h, respectively, indicating that speed and applied loads are inversely correlated （P 〈 0.001）. Heart rate was 129 ± 11 bpm at 700 kg, and in respect to resting state, donkeys＇ heart rate elevated by a factor of up to 3. As the load exceeded 400 kg, the speed declined significantly, and behavioural occurrences like heavy panting and falling down confirmed this. This leads to the conclusion that donkeys could pull about 2.7 times of their live weight. But if they have continuous and long working hours （about 6 h）, it is recommended to keep load of two wheeled cart about double of donkeys live weight so as to safe guard donkeys＇ welfare.
文摘The purpose of this paper is to improve allocation of the number of bits without skipping the frame by accurately estimating the target bits in H. 264/AVC rate control. The scheme ImPoses an enhancement method of the target frame rate based on H. 264/AVC bit allocation. The enhancement uses a frame complexion estimation to improve the existing Mean Absolute Difference （MAD） complexity measurement. Bit allocation to each frame is not just computed by target frame rote but also adjusted by a combined frame complexity measure. Using the statistical characteristic, the scheme obtains change of occurrence bit about QP to apply the bit amount by QP from the video characteristic and apply it in the estimated bit amount of the current frame. Simulation results show that the proposed rate eontrol scheme achieves time saving of mine than 99% over existing rate control algorithm. Nevertheless, Peak Signal-to-Noise Ration （PSNR） and bit rate were almost the same as the performances.
文摘Different teaching philosophies derive from different cultural background.There are many differences between American and Chinese teaching philosophies because of their different cultural background.Under the guidance of different philosophies,there are different teaching styles between American and Chinese Classroom teaching.
文摘 First of all it is necessary to point out that 'reciting' is the wrong term for what Chinese students are often asked to do when they are learning English. The correct terms are, 'learning by heart' or 'rote learning'. In this article the term 'rote learning' will be used.……
文摘This study investigates differential effects of etymological elaboration and rote memorization on idiom acquisition and retention in Chinese college EFL learners. The sample (N = 70) involved two intact groups of college students. Subjects in one group exposed to instruction in the form of etymological familiarity while subjects in the comparison group were asked to memorize idioms on the basis of their given meaning. Subjects were then administered two post-tests: one to assess initial idiom acquisition, and another four weeks later to assess idiom retention. Statistical analyses produced sufficient support for both the first hypothesis (that the etymological elaboration condition would acquire more idioms than the rote memorization condition), and the second hypothesis—that the etymological familiarity would exhibit superior retention rates. The finding of this study suggests that for the purpose of encouraging long-term retention, elaborating on the original usage of idioms is preferable to requiring students to learn idioms by rote.
文摘A systematic dependence of shape fluctuation energy product SFE ＊ B（E2）↑ and rotational energy product ROTE ＊ B（E2）↑ on the valence nucleon product Np Nn is carried out in the Z = 50-82,N = 82-126 major shell space.For the shape transitional nuclei,the product SFE＊B（E2）↑ drops to zero and becomes negative,indicating direct dependence on N_pN_n.A relative rise,on the other hand,is observed in the product ROTE＊B（E2） ↑plotted against N_pN_n for all the nuclei in Z = 50-82 and N = 82-126.In the N 〉 104 region,large positive values of the product SFE ＊ B（E2） ↑ are observed for the Pt nucleus,which indicates sphericity.A systematic study of the product SFE ＊ B（E2）↑ and ROTE ＊ B（E2） ↑ with atomic number Z is also discussed.The products SFE ＊ B（E2） ↑and ROTE ＊ B（E2） ↑ vary sharply with Z for the N = 88 isotones.We discuss here for the first time the correlation between SFE ＊ B（E2） ↑ and ROTE ＊ B（E2） ↑ with valence nucleon product N_pN_n.
