HOW TO IMPROVE THE HACCP SYSTEM IN AN INTERNATIONAL TOURIST HOTEL GROUP? CAUSE-AND -EFFECT ANALYSIS AND PDCA APPLICATION

The aim of this study is to discuss not only what the difficulties are to be confronted when a HACCP is introduced into international tourist hotels, but also how to apply effective solutions to overcome these crucial issues.  In-depth interviews were applied in this study to analyze the case of Taiwan’s X international tourist hotels. Based on the outcomes of interviews, a fish-bone diagram was carried out to analyze the practical difficulties encountered in implementing the HACCP system. Next, with the results of the cause and effect analysis, strategies for different problems were developed according to the interviewee’s points of view. PDCA analysis is used repeatedly to develop strategies and recommendations. In comparison to current literature that only provides piecemeal exploration of the difficulties of introducing the HACCP system and the effectiveness of implementing HACCP, this study takes an entire system view into consideration and enables further practical analysis and solutions.

APPLIED STUDY OF BIRCH PULP BLEACHING USING DIMETHYLDIOXIRANE TO OBTAIN ACETATE-GRADE PULP

As a pulp bleaching agent, dimethyldioxirane (DMD) is effective and selective. In this study, it was employed as a delignifying agent or as an activating agent for hydrogen peroxide treatment in bleaching acetate-grade pulp. Brightness, kappa number, degree of polymerization (DP), and alpha-cellulose content were evaluated to determine the optimal charges of DMD: 2.5% AO, and 4% HSO5-, respectively. Results from the totally chlorine-free (TCF) sequences MEQMPA, MEpQMPA, and OQMPA suggested that DMD is both effective and selective as a delignifying agent but not as a brightening agent as compared to oxygen. And in a long sequence for the bleaching of dissolving pulp, acid treatment can be used in two approaches: to remove the metal ions without washing before the chelation stage, and to reduce hemicellulose and ash in the final stage

Genomic Inference of the Metabolism and Evolution of the Archaeal Phylum Aigarchaeota

Microbes of the phylum Aigarchaeota are widely distributed in geothermal environments, but their physiological and ecological roles are poorly understood. Here we analyze six Aigarchaeota metagenomic bins from two circumneutral hot springs in Tengchong, China, to reveal that they are either strict or facultative anaerobes, and most are chemolithotrophs that can perform sulfide oxidation. Applying comparative genomics to the Thaumarchaeota and Aigarchaeota, we find that they both originated from thermal habitats, sharing 1154 genes with their common ancestor. Horizontal gene transfer played a crucial role in shaping genetic diversity of Aigarchaeota and led to functional partitioning and ecological divergence among sympatric microbes, as several key functional innovations were endowed by Bacteria, including dissimilatory sulfite reduction and possibly carbon monoxide oxidation. Our study expands our knowledge of the possible ecological roles of the Aigarchaeota and clarifies their evolutionary relationship to their sister lineage Thaumarchaeota

Near-fault mining induced microseismic distribution characteristics and its influencing factors

Rudarene u blizini konstrukcije s greškom može lako dovesti do aktiviranja greške i izazvati ozbiljne geološke poremećaje, predstavljajući ozbiljnu prijetnju sigurnosti proizvodnje uglja. Da bi pokazali karakteristike aktivnosti koje se javljaju u okolnoj stijeni zbog rudarenja u blizini područja s greškom, uzimajući Qixing ugljenokop u Kini kao tehnički ambijent, provela se kontrastivna analiza mikroseizmičkih kretanja u nadgledanom području s greškom na osnovu dobivenih mikroseizmičkih podataka. Promatrano sa stanovišta vrijednosti seizmičkog parametra b i rješenja žarišnog mehanizma, analizirale su se karakteristike širenja mikroseizmičkog događanja i načina loma u ta dva područja. Povećanjem područja rudarenja, provjeravale su se karakteristike razvijanja mikroseizmičkih događanja u okolnoj stijeni pod utjecajem obližnjih konstrukcija s greškom primjenom FLAC3D. Ustanovili smo da je b vrijednost u praćenom području s greškom mnogo niža od one u području nesigurnog rudarenja, što znači da postoji veća opasnost od pojave mikroseizmičkih poremećaja velikog opsega u prvom nego u drugom slučaju. Uz to, razlika u osnovnom naprezanju i elastičnoj energiji u području iskapanja pokazala je karakteristike diskontinuiranog rasprostiranja. Rezultati su pokazali da su postojale neke granične vrijednosti koje su uzrokovale rapidnu promjenu broja mikroseizmičkih pomaka s promjenom faktora kao što su dubina iskapanja, čvrstoća stijene i područje početnog naprezanja. Zaključci su od velike teorijske i praktične vrijednosti za slično rudarstvo.Mining near the fault structure can easily lead to the fault activity and induce serious geological disasters, posing a serious threat to coal mine safety production. To reveal the surrounding rock activity characteristics induced by near-fault mining, taking Qixing Coal Mine in China as the engineering background, the contrastive analysis of the microseismic events in the fault-control area and the mining disturbance area was conducted based on the microseismic monitoring data. From the point of views of seismic parameter b value and focal-mechanism solution, the microseismic event distribution characteristics and the fracture modes in those two areas were analyzed. With the mining area increasing, the evolution characteristics of the microseismic events in the surrounding rock affected by the near-fault structures were verified by using FLAC3D. We found that b value in the fault-control area was much lower than that in the mining disturbance area, indicating that the possibility of large-magnitude microseismic events was greater in the former than that in the latter. Moreover, the principal stress difference and the elastic energy in the mining area displayed the discontinuity distribution charateristics. The results showed that there were some threshold values making the microseismic event numbers change rapidly with these factors variation such as mining depth, rock strength and initial stress field. The conclusions are of important theoretical and practical value for the similar mining engineering

Gaussian quantum steering in multi-event horizon spacetime

We study Gaussian quantum steering in the Schwarzschild-de Sitter (SdS) spacetime which is endowed with both a black hole event horizon (BEH) and a cosmological event horizon (CEH), giving rise to two different Hawking temperatures. It is shown that the Hawking effect of the black hole always reduces the quantum steering, but the Hawking effect of the expanding universe not always plays the same role. For the first time, we find that the Hawking effect can improve quantum steering. We also find that the observer who locates in the BEH has stronger steerability than the observer who locates in CEH. Further, we study the steering asymmetry, and the conditions for two-way, one-way and no-way steering in the SdS spacetime. Finally, we study the Gaussian quantum steering in the scenario of effective equilibrium temperature. We show that quantum steering reduces monotonically with the effective temperature but now increases monotonically with the Hawking temperature of the black hole, which banishes the belief that the Hawking effect can only destroy quantum steering.Comment: 18 pages, 5 figure