With the development of next generation sequencing (NGS) technology, the variation of sequences represented as SNP between cultivars becomes available at genome level. The major domestic cultivars with high yield have been developed by breeding of indica and japonica, it is important to localize the region of origin according to the genotype for further characterization of unique features of cultivars. For the localization of SNP at genome level, the paired end sequences of 6 major domestic rice cultivars, Ilmi, Ilpoom, Sulgaeng, Bakjinju, Hwayoung and Woonkwang were compared against Japonica and Indica Rice Genomes as reference genomes. The genomic DNAs were prepared from callus tissues and paired-end of the fragments were sequenced with NGS Sequencer, Illumina HISeq. About 50x coverage of paired-end sequences were trimmed according to the quality of the sequences, and errors were corrected with statistical analysis of kmers of 15. The trim-corrected sequences were mapped and variants were analyzed against reference genomes. The overall change rate of Ilmi against Nipponbare IRGSP 1.0 and Indica BGI 93-11 reference genomes were 0.92 base/1kb (1/1,079 base) and 8.09 base/1kb (1 base/123 bases), respectively. Among 6 cultivars, overall rate of Bakjinju showed the lowest overall change rate of 0,53 base/1kb, and Hwayoung showed highest frequency of 0.92 base/1kb. Compared to high level in the range of change rate of 7.0-9.3 base/1kb against indica, domestic cultivars showed lower range of change rate 0.2-3.3 base/1kb with unique local high peak against japonica genome depend on the chromosomes. Compared to assembly of genome sequences, the variation of nucleotides compared to reference sequences is much faster and simple to characterize the genotype. The types of variation and the effect on functional categories will be presented.

There is a growing number of plant genomes that are being sequenced, but most of these available assemblies do not cover the entire genome mainly due to the highly repetitive sequences found in most plant genomes. Nevertheless, these repeats, although a challenge in assembly algorithms, provide relevant information about a genome’s history that could help explain its structure and complexity. Here, we cytogenetically mapped previously and presently characterized major repeats of Panax ginseng genome, including several LTR retrotransposons (PgDel2, PgDel3, PgTat1, PgTat2, PgTork) and one tandem repeat, PgTR Fluorescence in situ hybridization (FISH) results showed differential accumulation of Ty3/gypsy LTR retrotransposons into different chromosomal regions or subgenomes, suggesting a non-random preferential amplification of retrotransposons in these regions and an allopolyploid origin of P. ginseng. In silico analysis based on 1x whole genome sequence reads suggests that PgTR is the most abundant tandem repeat in ginseng, which was further corroborated by FISH analysis. More importantly, its unique distribution pattern among the 24 ginseng chromosomes, coupled with the non-random distribution of LTR retrotransposons and rDNA arrays, allowed us to discriminate and characterize each individual ginseng chromosome. These different newly characterized cytogenetic markers allowed reorganization of previously reported ginseng karyotype with better resolution, demonstrating the irutility in ginseng chromosome identification. These information give us insight about the genomic structure of P. ginseng, and should be useful for future comparative cytogenetics studies among closely related species to unravel its genomic history. This work was supported by the Next-Generation BioGreen21 Program (No. PJ008202), Rural Development Administration, Republic of Korea.

This study was performed to analyze genetic relationship of the four major Cucurbitaceae crop. We used 120 Expressed Sequence Tag(EST)-Simple Sequence Repeat(SSR) primer sets of developed from watermelon and published in International Cucurbit Genomics Initiative (ICuGI) database. Among 120 EST-SSR primer, 51(49.17%) EST-SSR primer set successfully amplified and 49(40.8%) EST-SSR primer set showed polymorphisms among eight cultivars of Cucurbitaceae. In the first instance, amplified PCR products analysis was conducted by the agarose-gel electrophoresis then further analyzed by using Fragment Analyzer. A total 382 PCR band were producted by 49 EST-SSR primers in 24 plant panels, used the analysis of pairwise similarity and dendrogram construction. Assessment of the genetic relationships resulted in similarity index with range of 0.0103 to 0.8452. In dendrogram, 24 plant panels were formed three major groups (A, B, C) and 7 subgroups (A-1, A-2, B-1, B-2, B-3, C-1, C-2). Major group A was comprised of 2 subgroups, subgroup A-1 (6 watermelon cultivars, Citrullus lanatus var. vulgaris Schrad.) and subgroup A-2 (3 wild type watermelon, Citrullus lanatus var. citroides Mats. & Nakai). Major group B was comprised of 3 subgroups, subgroup B-1 (4 melon cultivars, Cucumis melo var. cantalupensis Naudin.), subgroup B-2 (2 oriental melon cultivars, Cucumis melo var. conomon Makino.) and subgroup B-3 (5 cucumber cultivars, Cucumis sativus L.). Major group C was comprised of 2 subgroups, subgroup C-1 [2 squash/ pumpkin cultivars, Cucurbita moschata (Duch. ex Lam.)/Duch. & Poir. and Cucurbita maxima Duch.] and subgroup C-2(2 squash/pumpkin cultivars, Cucurbita pepo L./Cucurbita ficifolia Bouche.)

With the development of next generation sequencing (NGS) technology, the variation of sequences represented as SNP between cultivars becomes available at genome level. The major domestic cultivars with high yield have been developed by breeding of indica and japonica, it is important to localize the region of origin according to the genotype for further characterization of unique features of cultivars. For the localization of SNP at genome level, the paired end sequences of 6 major domestic rice cultivars, Ilmi, Ilpoom, Sulgaeng, Baekjinju1ho, Hwayoung and Woongwang were compared against Japonica and Indica Rice Genomes as reference genomes. The genomic DNAs were prepared from callus tissues and paired-end of the fragments were sequenced with NGS Sequencer, Illumina HISeq2000. About 50x coverage of paired-end sequences were trimmed according to the quality of the sequences, and errors were corrected with statistical analysis of kmers of 15. The trim-corrected sequences were mapped and variants were analyzed against reference genomes. The overall change rate of Ilmi against Nipponbare IRGSP 1.0 and Indica BGI 93-11 reference genomes were 0.92 base/1kb (1/1,079 base) and 8.09 base/1kb (1 base/123 bases), respectively. Among 6 cultivars, overall rate of Baekjinju1ho showed the lowest overall change rate of 0,53 base/1kb, and Hwayoung showed highest frequency of 0.92 base/1kb. Compared to high level in the range of change rate of 7.0-9.3 base/1kb against indica, domestic cultivars showed lower range of change rate 0.2-3.3 base/1kb with unique local high peak against japonica genome depend on the chromosomes. Compared to assembly of genome sequences, the variation of nucleotides compared to reference sequences is much faster and simple to characterize the genotype. The types of variation and the effect on functional categories will be presented.

Bakanae disease is one of the most serious and oldest problems of rice production, which was first described in 1828 in Japan (Ito and Kimura 1931). This disease may infect rice plants from the pre-emergence stage to the mature stage, with severe infection of rice seeds resulting poor germination or withering (Iqbal et al. 2011). Under favorable environmental conditions, infected plants have the capacity to produce numerous conidia that subsequently infect proximate healthy plants, resulting in major yield loss (Ou 1985). One hundred sixty nine NILs, YR28297 (BC6F4) generated by five backcrosses of Shingwang with the genetic background of susceptible japonica variety, Ilpum were used for QTL analysis. Rice bakanae disease pathogen, CF283, was mainly used in this study and inoculation and evaluation of bakanae disease was performed with the method of the large-scale screening method developed by Kim et al. (2014). A major QTL for resistance against bakanae disease on chromosome 1 was identified using SSR marker, RM9, which explaining 65 % of the total phenotype variation. The major QTL designated as qBK1 and mapped to a 4.4 Mbp region between RM24 (19.30 Mb) and RM11295 (23.72 Mb). The results of this study are expected to provide useful information toward developing resistant rice lines to this detrimental fungal disease.

Glucosinolates (GLS) are secondary metabolites commonly occurring in Brassica crops and more than 130 different GLS have been reported in diverse plants. Recent studies have indicated that isothiocyanate (ITC) derived from GLS by hydrolysis had a potential for anticancer activity against several rumor cells on human. In addition, it was found that glucoraphenin (GRE) and glucoraphasatin (GRH) were abundant and differently regulated in radish plant, depending upon organs and developmental stages. Microspores isolated from flower buds of radish were cultured in vitro to obtain doubled haploid (DH; but homozygous) lines in a short time period. The present study was conducted to determine the concentration of GRE and GRH, an immediate precursor of ITC from DH lines of radish plant. Total 41 DH lines were selected based on flow cytometry analysis. The seeds, obtained by bud pollination from the DH lines, were planted and 3-weeks-old young seedlings were used for the major aliphatic GLS analysis. Amounts of GRH were highly variable from the DH lines ranging from 2.3 to 31.5 mg·g-1 dry weight (DW). The donor plant (DP) contained 18.4 mg·g-1 DW. It was noticed that there were 6-fold differences in the amounts of GRE between the highest and lowest DH lines. Among 41 lines tested, 14 DH lines of radish plant were significantly reduced in the amount of sum of GRH and GRE compared those of the donor plant (P<0.05), whereas only three lines increased. The results obtained in the present study will lend to select genotypes with low and high GLS contents of radish plant. In addition, those DH lines will aid to elucidate a biosynthetic pathway of the aliphatic GLS in radish plant, which remain for the most part unsolved.

Increasing demand on cereal grains to meet the population growth requires more production of rice as well as other cereals, which is supposed to rise up to 40% until 2030. Grain size and shape are critical factors determining grain yield. Several genes on grain shape and size have been reported, and of them, seven cloned genes were chosen for haplotype analysis, such as GS3, GW2, qSW5, GS6, GW8, GS5, and TGW6. We genotyped 218 rice varieties which had diverse grain size and shape originating from 25 countries. As for GS3 and qSW5, PCR markers were developed for point mutation and deletion, respectively. For the other five genes in which functional SNPs were reported, we designed primer sets to distinguish a fuctional allele for each gene. GW2 and TGW6 had two alleles, while the other five genes displayed three alleles which were evenly distributed throughout the population. Analysis on the relationship between haplotype of the genes and grain phenotype is in progress. We expect that desirable allelic combination of genes would assure the optimal grain size and shape for higher grain yield and market quality. This work was supported by a grant from the Next-Generation BioGreen 21 Program (Plant Molecular Breeding Center No.PJ009076), Rural Development Administration, Republic of Korea.

Bakanae disease incidence threat is an increasing trend in the top rice growing countries. Despite it is essential to identify the resistant genes and underlying mechanisms of bakanae disease to develop resistant varieties, there are very limited genetic studies on bakanae disease in rice. The indica rice variety Shingwang was selected as resistant donor to bakanae disease. One hundred sixty nine NILs, YR28297 (BC6F4) generated by five backcrosses of Shingwang with the genetic background of susceptible japonica variety, Ilpum were used for QTL analysis. Rice bakanae disease pathogen, CF283, was mainly used in this study and inoculation and evaluation of bakanae disease was performed with the method of the large-scale screening method developed by Kim et al. (2014). The proportion of healthy plants of Shingwang and Ilpum after inoculation was confirmed using bakanae disease pathogen, CF283. While inoculated Ilpum showed thin and yellowish-green phenotype which is typical symptom of Bakanae disease, Shingwang showed similar healthy phenotype with control plants. A major QTL for resistance against bakanae disease on chromosome 1 was identified using SSR marker, RM9, which explaining 65 % of the total phenotype variation. The major QTL designated as qBK1 and mapped to a 4.4 Mbp region between RM24 (19.30 Mb) and RM11295 (23.72 Mb). The information of qBK1 could be useful for improving rice bakanae disease resistance in marker-assisted breeding.

21세기의 디자인대학 교육에 거는 기대는 매우 다양하다. 이러한 사회적, 시대적 요구에 맞는 교육을 위한 대학의 노력은 절실하다. 디자인 대학은 디자인 관련 전문지식과 융합, 변화하는 사회가 인간에게 행복을 줄 수 있는 가치를 중심으로 다양한 자구책을 마련하고 실천하고 있다. 이와 함께 취업을 위한 현장실습과 디자인 능력 극대화와 중간과정 평가를 위한 수단으로서 국내외 공모전은 디자인대학에 필요하다. 국내외 공모전은 학생들의 실질적인 관심과 성취도에 영향을 주고 있는 것이 사실이다. 기업과 단체에서 공모전을 통한 공유하고자 하는 디자인의 요소와 대학의 기초적인 교육 내용과 만남의 긍정적 확대라는 측면이 절실하다. 가치융합디자인비지지니스 교육 과정의 4가지 요소를 중심으로 그 동안 참가하여 성과를 올렸던 주요 국제공모전의 공통적인 특성을 고려하여, 시사성. 구성. 완성도. 스타일. 파급효과 5가지 요소의 공통점 돌출을 통하여 가치융합디자인Biz와 공모전 연계를 통한 교육을 할 수 있는 과정과 체계를 필요로 한다. 기존 연구와 학문적 보완 그리고 교육 과정을 통하여 새로이 정립한 가치 디자인의 방법론의 14단계를 가치인식, 가치표현, 가치융합비즈(Biz), 가치 모델, 가치표현디자인, 가치 확대 요소 6가지와 세부 요소 28 단계 단계로 나누어서, 시사성. 구성. 완성도. 스타일. 파급효과 5가지 요소와의 연계를 명확하게 하였다. 아직 대학과 기업. 단체 사이에 공모전에 대한 연구가 없음으로, 이번 연구가 대학의 가치융합디자인Biz과 공모전 연계 교육을 위한 연계교육표를 중심으로 학습 과정(Process)과 체계(System)를 통한 디자인 방법론 모델(Model) 제시를 통한 학생들의 실질적인 관심과 성취도 향상에 도움 되기를 바란다.

Mercury distribution and hazardous characteristics of major components from SCFLs (Spent compact fluorescent lamps)for 3 lamp manufactures (A, B, C) are estimated by the analysis of mercury concentration and leaching tests such asKorean Extraction Test (KET) and Toxicity Characteristic Leaching Procedure (TCLP). SCFLs can be separated into glasstube, phosphor powder, metals, ballast, plastics, and binder. Through the analysis of mercury in major components forSCFL, mercury concentration in phosphor powder is much higher than that in other components regardless manufacturesof lamp. Also, mercury concentration in phosphor powder is dependent of the manufactures of lamp. From the leachingtests, all components except phosphor powder from 3 lamp manufactures are verified to be non-hazardous waste becauseall leaching concentrations are below the regulatory level. However, the leaching concentration of mercury in phosphorpowder of SCFLs is higher than the regulatory level in both KET and TCLP regardless manufactures of lamp. Hence,phosphor powder should be managed as a hazardous waste and should be separately managed to control mercury.

이 논문에서 소개하는 질적 사례 연구는 문학과 예술적인 소양을 가졌던 연구참여자가 중등학교 시절부터 기독교 신앙생활을 하면서 활성화되었던 인문 예술적 소양이 점차 이공계 분야에서 발현되는 과정을 보여준다. IT 분야에서 일하는 한 명의 연구참여자(현웅)을 대상으로 초상화법에 따라 심층면담을 4회 실시하였으며 인물 사례 형태로 묘사하였다. 현웅의 삶에서 두드러지게 나타나는 부분은 가족관계의 정체성과 관련하여 그가 운명적으로 만나게 된 기독교 신앙이다. 두 차례의 이정표적인 신앙 체험을 통하여 그의 인문예술적 소양은 고등학교와 대학교 시절에 활짝 꽃을 피웠다. 기독교적인 메시지를 통하여 삶의 새로운 전환점을 맞이하게 되었으며 그 이후에 그가 가졌던 섬세하고 감성적인 글쓰기 소양이 논리적인 컴퓨터 프로그래밍 작업과 결합되었다. 이 인문 사례는 인문예술적 소양이 이공계적 전문성과 결합되는 통합적인 측면과 현웅의 내적 소양이 고차적 양상과 연결되고 있음을 보여준다.

본 연구는 남부지역에서 주요 콩 품종의 파종기 이동이 isoflavone 등 생리활성물질에 미치는 영향을 구명하고자 전남 나주(위도 35° 04'N, 경도 126° 54'E)에서 2008년부터 2010년까지 3년간 수행되었다. 여름형콩 품종인 새올콩과 다원콩, 가을형콩 품종인 태광콩, 풍산나물콩 및 청자3호를 이용하여 파종기를 5월 15일, 5월 30일, 6월 15일, 6월 30일, 7월 15일에 실시하였으며, 주요 결과를 요약하면 다음과 같다. 1. Daidzein 함량은 모든 시험품종에서 genistein과 total isoflavone 함량은 청자3호를 제외한 시험품종에서 파종이 늦어질수록 증가하는 경향이었다. 반면에 glycitein 함량은 다원콩을 제외한 시험품종에서 파종기간 유의차가 없었다. 2. Cyanidin-3-glucoside(C3G) 함량은 다원콩과 청자3호, delphinidin-3-glucoside(D3G)와 total anthocyanin 함량은 다원콩에서만 파종이 늦어질수록 유의하게 증가하였다. 그러나 pelargonidin-3-glucoside(Pg3G)와 petunidin-3-glucoside(Pt3G) 함량은 파종기간 유의차가 없었다. 3. 청자3호의 lutein 함량은 파종기에 따라 2.7～3.0 μg/g로 유의차가 없었고, chlorophyll 함량은 파종이 늦어짐에 따라 증가하여 6월 30일과 7월 15일 파종에서 유의하게 많았다. 4. 조지방 함량은 태광콩과 청자3호는 조기에 파종할 때 많았고 기타 시험품종은 파종기간 유의차가 없었다. Palmitic acid 조성비는 대부분 시험품종에서 파종기의 영향을 받지 않았다. Stearic acid 조성비는 새올콩, 다원콩, 청자3호에서 파종이 늦을수록 증가하였다. Oleic acid, linoleic acid 조성비는 새올콩에서만 파종기가 빠를수록 유의하게 높았다. Linolenic acid 조성비는 대부분 시험품종에서는 파종이 늦을수록 유의하게 증가하였다. 5. 파종기 이동에 따른 탄수화물과 조단백질 함량은 대부분 시험품종에서 유의차가 없었다. 그러나 새올콩은 조기에 파종할수록, 다원콩은 만기에 파종할수록 조단백질 함량이 많은 경향이었다.

We have studied characteristics of community structure on the benthic macro-invertebrates at twelve selected sites in upstream, midstream and downstream of Paemsagol, Piagol, Chilseongol and Daeseonggol, major streams of Jirisan Mountain, for three years from April 2008 to September 2010. As a result, 2 phyla, 3 classes, 11 orders, 41 families, 119 species and 4,449 individuals of benthic macro-invertebrates have been collected and classified in this study. Among them EPT group (Ephemeroptera, Plecoptera, Trichoptera), commonly appearing taxa in clean stream ecosystem, was found most frequently. The highest species number of benthic macro-invertebrates were collected in 2008, the year with lower climatic influence including heavy rain. In almost all of survey sites 80% or over of EPT group were counted, and St. 1 scored highest rate of EPT group at 92.59%. Most dominant species was Ecdyonurus kibumensis at 12.83% of dominance index, and subdominant species was Goerodes KUb at 6.81% of dominance index. The investigation of the feeding function group indicated that gathering-collectors were dominant with 26 species and 1,334 individuals, while the number of filtering-collectors was lowest with 11 species and 230 individuals. This result represents that the feeding function group of Jirisan Mountain is mountainous stream-specific one. Both diversity index and richness index were lowest at the midstream of Chilseongol (St. 5), while the midstreams of Daeseonggol (St. 11) and Piagol (St. 8) were highest in diversity and richness indices respectively. The analyses of linear regression and correlation were performed in order to investigate and to predict the appearance aspect of EPT group by altitude. The results showed that the ratio of Plecopteran species number has increased by the elevation of the altitude at 0.05 significance level. Cluster analysis was also carried out for evaluating environmental similarities among survey sites. As a result, upper regions of Paemsagol (St. 1) and Piagol have clustered as most similar sites each other, while the midstream of Piagol (St. 8) has separated with lower similarity value than other sites in species composition.

본 연구는 원예재활 실습만족이 화훼원예전공생들의 직업준비의사에 영향을 미칠까?라는 연구의문을 가지고 원예재활 실습의 구성요소를 도출하여 이들이 직업준비의사에 미치는 영향의 정도를 통계적으로 분석했다. 연구절차는 선행연구를 통해 원예재활실습 구성요소를 심리적, 물리적, 교육적 범주로 14개의 변수를 도출하고 이를 현장에 맞게 조작적 정의를 내려 변수를 가공한 후 설문을 통해 실습에 참여한 화훼원예전공생 60명 전수를 대상으로 실증적 조사를 하였다. 조사의 내적 타당도와 측정도구의 신뢰성을 검증하고 회귀분석을 통해 직업준비의사에 미치는 만족 요인을 분석했을 때 자격증제도와 체계화 된 교구재가 가장 영향을 주는 것으로 나타났다. 따라서 화훼 원예 전공생이 원예재활을 직업으로 연계하려면 체계적인 시청각 교구재의 개발과 자격증 제도의 시스템과 같은 전문적인 지원체계를 구축하는 것이 필요하다는 연구결과는 원예재활프로그램의 정착에 기초자료로 활용될 수 있을 것이다.

인구의 고령화, 기후변화의 심화 및 적응실패, 자원·에너지의 고갈, 정치·경제적 전략에 따른 국제 정세 변화 등의 재난을 둘러싼 거시환경 즉, 정치, 경제, 사회, 기술, 환경 분야의 다양한 메가트렌드들은 재난에 직·간접적 영향을 주면서 변화를 초래한다. 따라서 본 연구에서는 미래재난의 다양한 모습을 예측하기 위하여, 글로벌 리스크에 대한 최근 국내 사회의 주요 이슈를 도출하고 이에 대한 함의를 도출하였다. 세계경제포럼(World Economic Forum, WEF)은 시대에 따라 전 세계가 직면하는 리스크의 변화를 파악하기 위해 경제·환경·지정학·사회·기술 분야의 리스크 조사 결과를 고찰 및 분석하여 매년 「글로벌 리스크 보고서」를 발표하고 있다. 본 연구에서는 「2012 글로벌 리스크 보고서」에서 제시된 50개의 리스크 중 발생가능성과 파급효과가 높은 핵심 리스크를 선별하였고, 전문가 면담을 통하여 국내 영향력이 가장 큰 ‘기후변화 적응실패’와 ‘수자원 공급위기’를 분석 대상 리스크로 선정하였다. 이슈 도출을 위한 분석에 사용된 자료는 2012년 5월 1일～2013년 10월 20일의 연합뉴스 기사로, 두 리스크에 대한 국내 사회의 이슈를 파악하기 위하여 리스크와 관련된 문서들을 추출하고 주요 토픽을 분석하였다. 기후변화 적응실패’를 주제로 추출된 3,093건의 문서들은 ‘곡물가격 급등’, ‘홍수·태풍 거대화’, ‘이상기후와 폭염’, ‘전력수급 계획’, ‘기후변화로 인한 작물 피해’, ‘생태계 환경변화’ 등 총 6개의 토픽으로 분류되었고, ‘수자원 공급위기’를 주제로 추출된 6,160건의 문서에서는 ‘폭염으로 인한 수자원 위기’와 ‘4대강과 녹조현상’, ‘농산물 공급위기’, ‘수온 상승과 적조현상’, ‘전력수급 위기’, ‘상하수도 공급’, ‘가축폐사 피해’, ‘수질오염과 식중독’과 같은 총 8가지 유의미한 토픽이 추출되었다. 본 연구에서는 각 토픽을 구성하고 있는 주요 키워드에 대한 빈도, 문서 수, 토픽 가중치 등의 정보와 기사 원문 검토를 통하여 토픽이 의미하고 있는 사회적 이슈를 파악하였으며, 재난과 연계될 가능성에 대해 검토하였다. 또한 본 연구에서는 환경부에서 2010년에 발표한 저탄소 녹색성장 기본법 시행에 따른 국가 기후변화 적응대책과 본 연구를 통해 추출된 토픽을 비교하여, 수립된 대책이 현재 국내 상황을 적절하게 고려하였는지에 대하여 검토하였고 그에 대한 시사점을 도출하였다. 이와 같이 주요 위험 주제에 대한 실제 국내 사회 이슈를 검토하여 정책 수립에 반영하는 과정은 더욱 현실적이고 체계적인 정책 수립에 기여할 수 있을 것이라 사료된다.

The study selected 10 regions among major Korean cities. Then the study classified the yearly change of relative humidity of those regions for 37 years based on 1996 (from 1974 to 2011) aimed at high temperature days, and examined them by stage regarding daily maximum temperature. For large cities and small cities, in general relative humidity had been likely to increase at high temperatures of 30℃ or over before 1996, whereas it has decreased since 1996. For suburban areas, relative humidity had been prone to diminish before 1996, whereas it has been likely to either increase since 1996 or rarely some of the cities have not shown any change. The increasing tendency of relative humidity before 1996 in large cities and small cities is believed to be because of an increase of the latent heat of vaporization by the supply of steam from cooling towers established in downtown areas. Meanwhile, the decreasing tendency from 1996 is concluded to be caused by the change from counter-current circular cooling towers, which produce a great quantity of steam including arsenic acid, to cross-flow cooling towers, which produce hardly any steam containing arsenic acid. This change was in accordance with the modification and pursuit of an urban planning law that ordered cooling towers that had been installed on rooftops be installed in the basement of buildings in consideration of a “Green network creation” project by the Ministry of Environment, urban beautification, concerns since 1996 over building collapses, and according to an argument that steam containing arsenic acid could be harmful to human health owing to chemicals contained in the water in the cooling tower in summer.