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Determinants of Mobile Application Use: A Study Focused on the Correlation between Application Categories (모바일 앱 사용에 영향을 미치는 요인에 관한 연구: 앱 카테고리 간 상관관계를 중심으로)

  • Park, Sangkyu;Lee, Dongwon
    • Journal of Intelligence and Information Systems
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    • v.22 no.4
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    • pp.157-176
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    • 2016
  • For a long time, mobile phone had a sole function of communication. Recently however, abrupt innovations in technology allowed extension of the sphere in mobile phone activities. Development of technology enabled realization of almost computer-like environment even on a very small device. Such advancement yielded several forms of new high-tech devices such as smartphone and tablet PC, which quickly proliferated. Simultaneously with the diffusion of the mobile devices, mobile applications for those devices also prospered and soon became deeply penetrated in consumers' daily lives. Numerous mobile applications have been released in app stores yielding trillions of cumulative downloads. However, a big majority of the applications are disregarded from consumers. Even after the applications are purchased, they do not survive long in consumers' mobile devices and are soon abandoned. Nevertheless, it is imperative for both app developers and app-store operators to understand consumer behaviors and to develop marketing strategies aiming to make sustainable business by first increasing sales of mobile applications and by also designing surviving strategy for applications. Therefore, this research analyzes consumers' mobile application usage behavior in a frame of substitution/supplementary of application categories and several explanatory variables. Considering that consumers of mobile devices use multiple apps simultaneously, this research adopts multivariate probit models to explain mobile application usage behavior and to derive correlation between categories of applications for observing substitution/supplementary of application use. The research adopts several explanatory variables including sociodemographic data, user experiences of purchased applications that reflect future purchasing behavior of paid applications as well as consumer attitudes toward marketing efforts, variables representing consumer attitudes toward rating of the app and those representing consumer attitudes toward app-store promotion efforts (i.e., top developer badge and editor's choice badge). Results of this study can be explained in hedonic and utilitarian framework. Consumers who use hedonic applications, such as those of game and entertainment-related, are of young age with low education level. However, consumers who are old and have received higher education level prefer utilitarian application category such as life, information etc. There are disputable arguments over whether the users of SNS are hedonic or utilitarian. In our results, consumers who are younger and those with higher education level prefer using SNS category applications, which is in a middle of utilitarian and hedonic results. Also, applications that are directly related to tangible assets, such as banking, stock and mobile shopping, are only negatively related to experience of purchasing of paid app, meaning that consumers who put weights on tangible assets do not prefer buying paid application. Regarding categories, most correlations among categories are significantly positive. This is because someone who spend more time on mobile devices tends to use more applications. Game and entertainment category shows significant and positive correlation; however, there exists significantly negative correlation between game and information, as well as game and e-commerce categories of applications. Meanwhile, categories of game and SNS as well as game and finance have shown no significant correlations. This result clearly shows that mobile application usage behavior is quite clearly distinguishable - that the purpose of using mobile devices are polarized into utilitarian and hedonic purpose. This research proves several arguments that can only be explained by second-hand real data, not by survey data, and offers behavioral explanations of mobile application usage in consumers' perspectives. This research also shows substitution/supplementary patterns of consumer application usage, which then explain consumers' mobile application usage behaviors. However, this research has limitations in some points. Classification of categories itself is disputable, for classification is diverged among several studies. Therefore, there is a possibility of change in results depending on the classification. Lastly, although the data are collected in an individual application level, we reduce its observation into an individual level. Further research will be done to resolve these limitations.

Frequency of Meals and Hyperlipogenesis of Rat (쥐의 급식회수(給食回數)와 체지방과잉합성(體脂肪過剩合成))

  • Han, In-K.
    • Applied Biological Chemistry
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    • v.7
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    • pp.21-27
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    • 1966
  • This experiment was performed to investigate the effect of the frequency of meals on the metatolism and the body composition of rats when equal amount of purified diet was ingested. Thirty approximately days old rats weighing 290 g and thirty-two about 40 days old rats weighing 180 g were employed for the period of 34 days. Rats fed ad libitum (10 to 15 meals per day) and two-meal per day were pair-fed and equal amount of diet was fed to each rat in pair. The experimental results obtained are summarized as follows: 1. Frequency of meal did not exert any effect on the body weight gain. However, rats fed two-meal per· day gained significantly (p <0.005) more fat and energy than ad libitum group. The rate of gain of protein in ad libitum group was higher than that of two-meal group. No difference was observed for the mineral deposition of rat body. 2. From the preperation of rat liver it was found that the activity of glucose-6-phosphate dehydrogenase was much higher for the rats fed two-meals per day than those fed ad libitum. Therefore, it is suggested that the metabolic pathway of carbohydrate for two-meal group has been shifted from glycolysis to Hexose Monophosphate Shunt and produced more NADPH which would be the essential cofactor of fatty acids synthesis. 3. The rate of excretion of urinary nitrogen for two-meal group was significantly (p<0.005) higher than that of ad libitum group. It is apparent that considerable amount of over-loaded amino acids by feeding two-big-meal daily· could not be used for the protein biosynthesis all at once and excreted following deamination through urine. The residual carbon chain could be served as a precursor of fatty acids synthesis. 4. The heat production rate of rats fed two-meal group was significantly (p<0.005) lower than that of ad libitum group. It seems possible that the activity of thyroid gland (and consequently BMR) can be depressed by the frequency of meal.

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Selective Word Embedding for Sentence Classification by Considering Information Gain and Word Similarity (문장 분류를 위한 정보 이득 및 유사도에 따른 단어 제거와 선택적 단어 임베딩 방안)

  • Lee, Min Seok;Yang, Seok Woo;Lee, Hong Joo
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.105-122
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    • 2019
  • Dimensionality reduction is one of the methods to handle big data in text mining. For dimensionality reduction, we should consider the density of data, which has a significant influence on the performance of sentence classification. It requires lots of computations for data of higher dimensions. Eventually, it can cause lots of computational cost and overfitting in the model. Thus, the dimension reduction process is necessary to improve the performance of the model. Diverse methods have been proposed from only lessening the noise of data like misspelling or informal text to including semantic and syntactic information. On top of it, the expression and selection of the text features have impacts on the performance of the classifier for sentence classification, which is one of the fields of Natural Language Processing. The common goal of dimension reduction is to find latent space that is representative of raw data from observation space. Existing methods utilize various algorithms for dimensionality reduction, such as feature extraction and feature selection. In addition to these algorithms, word embeddings, learning low-dimensional vector space representations of words, that can capture semantic and syntactic information from data are also utilized. For improving performance, recent studies have suggested methods that the word dictionary is modified according to the positive and negative score of pre-defined words. The basic idea of this study is that similar words have similar vector representations. Once the feature selection algorithm selects the words that are not important, we thought the words that are similar to the selected words also have no impacts on sentence classification. This study proposes two ways to achieve more accurate classification that conduct selective word elimination under specific regulations and construct word embedding based on Word2Vec embedding. To select words having low importance from the text, we use information gain algorithm to measure the importance and cosine similarity to search for similar words. First, we eliminate words that have comparatively low information gain values from the raw text and form word embedding. Second, we select words additionally that are similar to the words that have a low level of information gain values and make word embedding. In the end, these filtered text and word embedding apply to the deep learning models; Convolutional Neural Network and Attention-Based Bidirectional LSTM. This study uses customer reviews on Kindle in Amazon.com, IMDB, and Yelp as datasets, and classify each data using the deep learning models. The reviews got more than five helpful votes, and the ratio of helpful votes was over 70% classified as helpful reviews. Also, Yelp only shows the number of helpful votes. We extracted 100,000 reviews which got more than five helpful votes using a random sampling method among 750,000 reviews. The minimal preprocessing was executed to each dataset, such as removing numbers and special characters from text data. To evaluate the proposed methods, we compared the performances of Word2Vec and GloVe word embeddings, which used all the words. We showed that one of the proposed methods is better than the embeddings with all the words. By removing unimportant words, we can get better performance. However, if we removed too many words, it showed that the performance was lowered. For future research, it is required to consider diverse ways of preprocessing and the in-depth analysis for the co-occurrence of words to measure similarity values among words. Also, we only applied the proposed method with Word2Vec. Other embedding methods such as GloVe, fastText, ELMo can be applied with the proposed methods, and it is possible to identify the possible combinations between word embedding methods and elimination methods.

The influencing effect on E.Q. and personality that both sports activity & speciality aptitude activity in school-childhood can cause (학동기의 스포츠활동과 특기적성활동의 참가가 감성지수 및 성격특성에 미치는 영향)

  • Lee Han-Ki
    • The Journal of Korean Physical Therapy
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    • v.16 no.1
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    • pp.140-156
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    • 2004
  • This study, to find whether a sports activity and a speciality aptitude activity in school-childhood can affect in forming E.Q, has been done in Gyoung-Nam area and Busan wide city with asked 222 of men and women being in their school-childhood and a group of 85 people who had not joined in such activity, using a E.Q testing paper provided by Dae-Gyo Education Corp,. and Seoul National University Educational Research Institute. Following is the results after analyzing the compiled datas. 1. The E.Q. level difference between people who joined, and who not joined in a sports action activity was reported existing, the total E.Q average of those who joined was resulted 212.6, a point 29.6 higher than those not joined of 183.0 ( p< .05). As for the E.Q causing points, it resulted that the points of the joined group is generally up than that of the non-joined group, especially this difference was remarkable in terms of feeling recognition or feeling control, a finding that deserves an attention ( p<.05) 2. Joining periods of sports activity did also have relation to develping E.Q. of school-childhood according to this research, the total E.Q points of a group joined in the activity more than 2 years was 215.5 points, which was 17.4 points higher than those not joined of 186.5 points ( p< .05). Backing again to E.Q causing points in this case, it resulted without exeption of all main causes that those who joined in more than 2 years are generally higher than that of those joined less than 2 years, especially the difference was regarded as big in terms of feeling recognition or feeling control, a finding that deserves an attention ( p<.01). 3. The E.Q. differnce between those joined in a specialty aptitude activity and not joined was studied existing, the total E.Q average points of those joined in a specialty aptitude activity was 207.8, a higher figure by 21.3 points than those not joined group of 186.5 ( p< .05). As for the E.Q causing points, it resulted without exeption of all main causes that those who joined are generally higher than that of those not joined, especially for feeling recognition or feeling control, this difference was more clear, a finding that deserves an attention ( p<.01). 4. It also resulted that E.Q growth depends on the periods to have joined in a speciality aptitude activity, for example, the total E.Q points of those joined in the activity more than 2 years was 217.1, a total more higher by 13.5 points than 203.6 of those not joined ( p< .05). For the E.Q. causing points, it, with the exception of empathy was resulted that those who joined in the speciality aptitude activity more than 2 years are generally higher than those joined less than 2 years, especially the difference is remarkable in terms of feeling recognition or feeling control, a finding that is also remarkable ( p<.05). 5. The E.Q difference between the men and women who joined in both activities of sports & speciality aptitude was found existing, the total E.Q. average for women was resulted 214.2 points, which was 9.2 points higher than men of 205.0. As for the E.Q. causing points, which, without exeption of main causes, women's was reported being high than that of men, in special is more remarkable in terms of feeling control, a finding that deserves an attention. ( p<.05).

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The Relationship between Internet Search Volumes and Stock Price Changes: An Empirical Study on KOSDAQ Market (개별 기업에 대한 인터넷 검색량과 주가변동성의 관계: 국내 코스닥시장에서의 산업별 실증분석)

  • Jeon, Saemi;Chung, Yeojin;Lee, Dongyoup
    • Journal of Intelligence and Information Systems
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    • v.22 no.2
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    • pp.81-96
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    • 2016
  • As the internet has become widespread and easy to access everywhere, it is common for people to search information via online search engines such as Google and Naver in everyday life. Recent studies have used online search volume of specific keyword as a measure of the internet users' attention in order to predict disease outbreaks such as flu and cancer, an unemployment rate, and an index of a nation's economic condition, and etc. For stock traders, web search is also one of major information resources to obtain data about individual stock items. Therefore, search volume of a stock item can reflect the amount of investors' attention on it. The investor attention has been regarded as a crucial factor influencing on stock price but it has been measured by indirect proxies such as market capitalization, trading volume, advertising expense, and etc. It has been theoretically and empirically proved that an increase of investors' attention on a stock item brings temporary increase of the stock price and the price recovers in the long run. Recent development of internet environment enables to measure the investor attention directly by the internet search volume of individual stock item, which has been used to show the attention-induced price pressure. Previous studies focus mainly on Dow Jones and NASDAQ market in the United States. In this paper, we investigate the relationship between the individual investors' attention measured by the internet search volumes and stock price changes of individual stock items in the KOSDAQ market in Korea, where the proportion of the trades by individual investors are about 90% of the total. In addition, we examine the difference between industries in the influence of investors' attention on stock return. The internet search volume of stocks were gathered from "Naver Trend" service weekly between January 2007 and June 2015. The regression model with the error term with AR(1) covariance structure is used to analyze the data since the weekly prices in a stock item are systematically correlated. The market capitalization, trading volume, the increment of trading volume, and the month in which each trade occurs are included in the model as control variables. The fitted model shows that an abnormal increase of search volume of a stock item has a positive influence on the stock return and the amount of the influence varies among the industry. The stock items in IT software, construction, and distribution industries have shown to be more influenced by the abnormally large internet search volume than the average across the industries. On the other hand, the stock items in IT hardware, manufacturing, entertainment, finance, and communication industries are less influenced by the abnormal search volume than the average. In order to verify price pressure caused by investors' attention in KOSDAQ, the stock return of the current week is modelled using the abnormal search volume observed one to four weeks ahead. On average, the abnormally large increment of the search volume increased the stock return of the current week and one week later, and it decreased the stock return in two and three weeks later. There is no significant relationship with the stock return after 4 weeks. This relationship differs among the industries. An abnormal search volume brings particularly severe price reversal on the stocks in the IT software industry, which are often to be targets of irrational investments by individual investors. An abnormal search volume caused less severe price reversal on the stocks in the manufacturing and IT hardware industries than on average across the industries. The price reversal was not observed in the communication, finance, entertainment, and transportation industries, which are known to be influenced largely by macro-economic factors such as oil price and currency exchange rate. The result of this study can be utilized to construct an intelligent trading system based on the big data gathered from web search engines, social network services, and internet communities. Particularly, the difference of price reversal effect between industries may provide useful information to make a portfolio and build an investment strategy.

The Effect of Family-Centered Coaching Based on Sensory Integration on the Performance of Children with Autism Spectrum Disorder (감각통합 기반의 가족중심코칭이 자폐스펙트럼장애 아동의 작업수행에 미치는 효과)

  • Kim, Yoon-Sung;Kim, Kyeong-Mi;Chang, Moon-Young;Hong, So Young
    • The Journal of Korean Academy of Sensory Integration
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    • v.19 no.2
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    • pp.12-25
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    • 2021
  • Objective : This study explored the effects of family-centered coaching using a sensory integration-based approach on the levels of performance and satisfaction for children with autism spectrum disorder (ASD). Methods : From April 16, 2020 to August 6, 2020, participants included 10 children with ASD, between the ages of three to six who met the inclusion criteria, and their guardians. I used the Canadian Occupational Performance Measure (COPM) to evaluate the children's levels of performance and satisfaction and the Goal Attainment Scaling (GAS) to evaluate their occupational performance. The experimental group (n=5) continued the sensory integration therapy while receiving their personalized family-centered coaching training for 60 minutes per week. This continued for four weeks via home visits and video calls. The control group (n=5) also continued to receive the sensory integration therapy while receiving sensory integration-based general counseling in relation to activity objectives. Results : Statistically significant differences were found in the scores of COPM performance and satisfaction and the GAS scores between the experimental group and the control group, before and after the intervention (p<.05). Statistically significant differences were found in score changes in COPM and GAS, between the two groups (p<.05). Cohen's d also showed a big effect size on the scores of COPM satisfaction (d=2.768) and the GAS scores (d=2.786). Conclusion : This study demonstrated that the sensory integration-based, family-centered coaching had more positive effects on the level of performance and satisfaction of children with ASD, than general counseling.

A Study on the Protection of Personal Information in the Medical Service Act (의료법의 개인정보보호에 관한 연구)

  • Sung, Soo-Yeon
    • The Korean Society of Law and Medicine
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    • v.21 no.2
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    • pp.75-103
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    • 2020
  • There is a growing voice that medical information should be shared because it can prepare for genetic diseases or cancer by analyzing and utilizing medical information in big data or artificial intelligence to develop medical technology and improve patient care. The utilization and protection of patients' personal information are the same as two sides of the same coin. Medical institutions or medical personnel should take extra caution in handling personal information with high environmental distinct characteristics and sensitivity, which is different from general information processors. In general, the patient's personal information is processed by medical personnel or medical institutions through the processes of collection, creation, and destruction. Still, the use of terms related to personal information in the Medical Service Act is jumbled, or the scope of application is unclear, so it relies on the interpretation of precedents. For the medical personnel or the founder of the medical institution, in the case of infringement of Article 24(4), it cannot be regarded that it means only medical treatment information among personal information, whether or not it should be treated the same as the personal information under Article 23, because the sensitive information of patients is recorded, saved, and stored in electronic medical records. Although the prohibition of information leakage under Article 19 of the Medical Service Act has a revision; 'secret' that was learned in business was revised to 'information', but only the name was changed, and the benefit and protection of the law is the same as the 'secret' of the criminal law, such that the patient's right to self-determination of personal information is not protected. The Privacy Law and the Local Health Act consider the benefit and protection of the law in 'information learned in business' as the right to self-determination of personal information and stipulate the same penalties for personal information infringement such as leakage, forgery, alteration, and damage. The privacy regulations of the Medical Service Act require that the terms be adjusted uniformly because the jumbled use of terms can confuse information subjects, information processors, and shows certain limitations on the protection of personal information because the contents or scope of the regulations of the Medical Service Law for special corporations and the Privacy Law may cause confusion in interpretation. The patient's personal information is sensitive and must be safely protected in its use and processing. Personal information must be processed in accordance with the protection principle of Privacy Law, and the rights such as privacy, freedom, personal rights, and the right to self-determination of personal information of patients or guardians, the information subject, must be guaranteed.

The Present Situation and Challenges of the Russian Music Industry: Centered on the Digital Sound Sources (러시아 음악 산업 현황과 과제 - 디지털 음원을 중심으로 -)

  • Kwon, ki-bae;Kim, Se-il
    • Cross-Cultural Studies
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    • v.50
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    • pp.395-424
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    • 2018
  • The purpose of this paper is to examine the current situation and background of the Russian consumer music market, where digital music sources are making great strides in the noted recent years. In addition, music storage technology, media and change are considered together in this report. Moreover, Russia is the 12th largest music market in the world. The Russian music industry is following the recent trend of the global music industry, where the digital music market is growing rapidly on many different levels. The explosive growth of the digital sound sources in Russia's music industry is attributed to the explosive increase in available consumer downloads, streaming sound source service, and the increase in the number of digital sound sources using mobile technologies due to the development of the Internet. In particular, the sales of the available and accessible streaming sound sources are expected to grow explosively by the year 2020, which is expected to account for more than 85% of total digital music sales. In other words, the spread of smartphones and the resulting changes in the lifestyle of the Russians have created these changes for the global consumer of music. In other words, the time has come for anyone to easily access music and listen to music without a separate audio or digital player. And the fact that the Russian government's strong policy on the eradication of illegal copying of music is becoming an effective deterrent, as is also the factor that led to the increase of the share of the digital sound source to increase sales in Russia. Today, the Russian music industry is leading this change through the age and process of simply adapting to the digital age. Music is the most important element of cultural assets, and it is the beneficial content, which drives the overall growth of the digital economy. In addition, if the following five improvements(First, strengthen the consciousness of the Russian people about copyright protection; Second, utilizing the Big Data Internet resources in the digital music industry; Third, to improve the monopoly situation of digital music distributors; Fourth, distribution of fair music revenues; and Fifth, revitalization of a re-investment in the current Russian music industry) are effective and productive, Russia's role and position in the world music market is likely to expand.

A Study on Operation Systems of Preservation & Repair Expenses for Architectural Heritage in Japanese Colonial Era - Focused on Classification of Preservation Cost Construction & Preservation Cost-Aided Construction - (일제강점기 「고건축물」 보존수리 공사비용 운용시스템에 관한 연구 - 「보존비공사」와 「보존비보조공사」 분류체계에 대하여 -)

  • Seo, Dong-Chun
    • Korean Journal of Heritage: History & Science
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    • v.50 no.4
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    • pp.82-103
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    • 2017
  • Systems operating construction expenses for preservation and repair of the architectural heritage may be divided into two in the Japanese colonial era. They are preservation cost nd preservation cost-aided constructions, according to the ownership of a building. Preservation cost construction refers to preservation and repair of government-owned buildings that Japanese Government General of Korea had the ownership and the right of management, and preservation cost-aided construction means preservation and repair of private buildings such as Buddhist temples. In the case of preservation and repair of buildings owned by the government, it was done by the Japanese Government General of Korea, so the same agent executed the budget and managed the properties. They included royal tombs and relics, old government offices, Hyanggyo and some Seowon. On the other hand, in the case of preservation and repair of private buildings, they were private properties, so Japanese Government General of Korea had rights only for permission of preservation and repair. If there was a request for .preservation and repair by an owner, the Japanese Government General of Korea decided on whether it would support its expenses or not and played a role of management and supervision. It applied to Buddhist shrines and pagodas owned by Buddhist temples and shrines and temples owned by individuals and families. Hence, in the case of government-owned buildings, because the preservation cost was spent from the Japanese Government General of Korea's budget for investigation expenses of historical remains or repair expenses of Jeolleung and ruins, they were classified into preservation cost constructions. As for private buildings, the cost was spent from their budget for aiding preservation expenses, so they were classified into preservation cost-aided constructions. Because preservation cost construction and preservation cost-aided construction were conducted by two different agents, there were a little difference in procedures for executing a construction. There was no big difference in the general progress of constructions but was an administrative difference in the kinds of documents submitted and the roles of field supervisors. Such dual systems remained unimproved throughout the Japanese colonial era. The Japanese Government General of Korea was the colonial government so much influenced by the Japanese Government. Most Japanese architectural heritage was owned by Buddhist temples and Shinto shrines and there was almost no building owned by the government, resulting in a unitary system unlike Korea. Heritage system by the Japanese Government General of Korea was established under the influence of Japan regardless of the situation in Korea. Accordingly, Japanese Government General of Korea could not present a definite solution in the bisected system of preservation and repair expenses for the heritage. It shows the limits of the Japanese Government General of Korea in the colonial era.

Comparison of Productivity and Feed Value at Different Harvest Stages and Seeding Methods of Bermudagrass and Bahiagrass Cultivars (Bermudagrass와 Bahiagrass의 품종별 수확시기 및 파종방법에 따른 생산성 및 사료가치 비교)

  • Lee, Wang Shik;Im, Suk Ju;Kim, Bum Jun;Kim, Young Jin;Kim, Dong Hoon;Hwang, Kyung Jun;Kim, Si Hyun;Woo, Jae Hoon;Park, Nam Geon
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.38 no.4
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    • pp.310-319
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    • 2018
  • The southern type grasses announced for the test were the Bermudagrass cultivars (Giant, Cheyenne, Mohawk, Panchero Frio, Common and Tifton 85) and the Bahiagrass cultivars (TifQuik, Tifton 9), and the changes in the productivity and nutrient content were surveyed in Jeju area (450m altitude). The different cultivars were sowed by broadcasting or drill seeding method, and Tifton 85 was transplanted from sprigs. The fresh and dry matter yield showed varying significant differences for different cultivars (p<0.05). The fresh yields of Tifton 85, TifQuik and Tifton 9 were excellent, compared to the other cultivars, and for the dry matter yield, Tifton 85 and Tifton 9 were excellent when compared to the other cultivars. Crude protein content showed significant differences among different cultivars (p<0.05). Cheyenne, Mohawk, Panchero Frio, and Common showed differences in the crude protein content by sowing method and harvest time (p<0.05). The different cultivars showed differences in the crude fiber content (p<0.05), and Tifton 9 registered significantly high content and Mohawk and Tifton 85 showed significant crude fiber content by harvest time (p<0.05). According to these results, the southern type grass cultivars showed big differences in the regenerative capacity against damage from frost, productivity, and nutrient content, so they need to be chosen according to the purposes, and to increase their usage, their evaluation needs to be conducted at various altitudes.