The realization of unaccentedness in Korean and Japanese pitch accent systems

In this paper, I discuss how unaccented words are realized in lexical pitch accent varieties of Korean and Japanese, focusing on Daegu/North Gyeongsang Korean. Previous studies such as Kenstowicz & Sohn (1997) and Jun et al. (2006) claim that Daegu Korean lacks an unaccented class. I show that the final-accented class in Daegu Korean proposed by Kenstowicz & Sohn (1997) and Jun et al. (2006) is in fact unaccented, comparing final-accented words in Daegu Korean with unaccented words in Tokyo Japanese in phrasal contexts. Most previous studies examined only the tone interaction between words and clitics to determine the accentedness or unaccentedness of the words, but this study demonstrates that phrasal prosody should also be considered to help identify the accentedness or unaccentedness of words

Evaluation of Performance of Heat Pump using R32 and HFO-mixed Refrigerant by Refrigeration Cycle Simulation and Loss analysis

R32 was selected as the alternative for R410A for mini-split air conditioners/heat pumps in Japan and have already phased out R410A in residential market. Recently several new alternatives for R410A have been proposed in order to achieve more close capacity to R410A and mitigate high discharge temperature issue of R32 as well as to reduce energy consumption. We selected R32 from among the candidates a few years ago; however it is important to continue comparing it to new candidates in search for an even better choice. We carried out the drop-in tests of the new refrigerant R32/R125/R1234yf (67/7/26) by comparing its COP and especially pressure loss to those of R410A, R32/R1234ze(E)(70/30), and R32, using residential mini-split type air conditioner. We conducted the drop-in tests by two types of method, actual measuring and especially simulated calculation. Adjusting compressor suction superheat and the amount of refrigerant charged into the system. Moreover, we measured the performance of the system with changing compressor speed in the wide range by variable frequency drive. Furthermore, we compared electricity consumption at the constant capacities, and analyzed the results precisely by loss analysis. As a result, we found that the COP of R32/R125/R1234yf (67/7/26) is better than R410A in many conditions and it achieves very close capacity to R410A, but COP at the same capacity is not as high as R32. The reason is that pressure losses are increased by adding R125 and R1234yf to R32. It was clarified, comparing losses with R410A, R32/1234ze(70/30), and R32. From the above, we confirmed that R32 is still the best choice at present. However, we will continue searching for a better alternative.

Performance Evaluation of Heat pump System using R32 and HFO-mixed Refrigerant in High Ambient Temperature.

R32 was selected as the alternative for R410A for mini-split air conditioners/heat pumps and already phased out R410A in residential market in Japan. Recently several new alternatives for R410A have been proposed in order to achieve more close capacity to R410A and mitigate high discharge temperature issue of R32 as well as to reduce energy consumption. We selected R32 from among the candidates a few years ago; however it is important to continue comparing it to new candidates in search for an even better choice. We carried out performance evaluation for the lower GWP refrigerant R32/R125/R1234yf (67/7/26) and R32. We also conducted the experiments in cooling operation at high ambient temperature. As the result, we found that the COP of R32 is superior to the blend because of its latent heat characteristic. In particular, as condensing temperature increases such as at high ambient temperature operation, latent heat of the blend obtains even smaller. Therefore, advantage of R32 in COP becomes more significant at high ambient conditions. From the above, we consider that R32 is still the best refrigerant at present. However, we will continue investigation in search for a better refrigerant

Evaluation and Optimization of System Performance using HFO-mix Refrigerants for VRF and Mini-split Air-Conditioner

Global demand for air conditioning is expected to increase continuously. In order to minimize the impact on the climate as a total amount of CO2 equivalent, it is essential to continue to search for better refrigerants. On the other hand, product size and cost are important factors in providing value to users. This time, while using the experiment result of the mini-split type air-conditioner reported in the past, in addition, we conducted a new experiment on multi-type VRF air-conditioner. Then, the difference in COP performance between R-410A and alternative candidate refrigerants was evaluated. In addition, we studied the product design using R-452 B, R-454 B by simulation and compare the size when the performance is made identical by changing the system specifications with alternative refrigerant candidates. As a result, common results were obtained in both systems. It was found that R-452B and R-454B have better performance than R-410A. On the other hand, it was found that these refrigerants need to increase both the indoor heat exchanger and the outdoor heat exchanger to 120% in order to obtain the same performance as R-32

Teanol, a new brominated sesquiterpene from the Thailand Laurencia mariannensis

We examined the constitution of Laurencia mariannensis collected from the east coast of Tean Island, Thailand. The structure of a new brominated rearranged cyclolaurane-type sesquiterpene, named teanol (1), is reported. This is the first report on biology and chemistry of the Thailand red algal genus Laurencia (Rhodomelaceae, Ceramiales)